Thyroid gland is one of most important endocrine glands in the body. It plays vital role in growth control and its measurements tends to change in respect to age, sex, weight and ethnic group of the individual. This s...Thyroid gland is one of most important endocrine glands in the body. It plays vital role in growth control and its measurements tends to change in respect to age, sex, weight and ethnic group of the individual. This study aimed to assess endemic goiter and to estimate the measurement of normal thyroid gland dimensions and thyroid hormones level in school-aged children using Ultrasonography and ELISA Technique in Eastern Sudan (Kassala state). A total of 100 subjects is 6 - 18 years (43 males, 57 females), and mean of age (9.73 ± 2.54 years). This study was done in the period from April 2016 to February 2017. All the subject undergone thyroid ultrasound and thyroid hormone level test. Subjects with history of goiter were excluded from the study, by thyroid dimension (length, height and diameter). Thyroid volume was estimated using ellipsoid formula and thyroid hormones (TSH, T3 and T4) using Toso full automation. The study revealed that 12 subjects of the study (12%) with goiter, 7 female (7%) and 5 males (5%) with age ranged 6 - 11 years with increase in TSH and T3 and decrease in T4 level. The mean of thyroid volumes for normal subject and subject of goiter are 4.93 ± 0.63, 5.4 ± 1.4 mL, respectively, and TSH, T3, T4 (1.8 ± 0.97, 2.4 ± 0.86 UIu/nL), (3.61 ± 0.32, 3.8 ± 0.55 Pg/Nl), (1.35 ± 1.23 ng/DI level respectively). It concluded that there was positive correlations between the age and the thyroid volume (p = 0.65). It increases with increase of the age. The Rt lobe is larger than the Lt lobe;the thyroid volume is higher in male than female, and this study found the TSH and T3 decreased with ages while T4 increased with ages in normal subject;TSH and T3 level increased and T4 level decreased in goiter children.展开更多
BACKGROUND Elderly giant retrosternal thyroid goiter is a rare yet significant medical condition,often presenting clinical symptoms that can be confused with other diseases,posing diagnostic and therapeutic challenges...BACKGROUND Elderly giant retrosternal thyroid goiter is a rare yet significant medical condition,often presenting clinical symptoms that can be confused with other diseases,posing diagnostic and therapeutic challenges.This study aims to delve into the characteristics and potential mechanisms of this ailment through pathological diagnosis and immunohistochemical analysis,providing clinicians with more precise diagnostic and treatment strategies.A 77-year-old male,was admitted to hospital with the chief complaint of finding a goiter in the semilunar month during physical examination,accompanied by dyspnea.Locally protruding into the superior mediastinum,the adjacent structure was compressed,the trachea was compressed to the right,and the local lumen was slightly narrowed.The patient was diagnosed with giant retrosternal goiter.Considering dyspnea caused by trachea compression,our department planned to perform giant retrosternal thyroidectomy.Immunohistochemical results:Tg(+),TTF-1(+),Calcitonin(CT)(I),Ki-67(+,about 20%),CD34(-).Retrosternal goiter means that more than 50%of the volume of the thyroid gland is below the upper margin of the sternum.As retrosternal goiter disease is a relatively rare disease,once the disease is diagnosed,it should be timely surgical treatment,and the treatment is more difficult,the need for professional medical team for comprehensive treatment.CONCLUSION The imaging manifestations of giant retrosternal goiter are atypical,histomorphology and immunohistochemistry can assist in its diagnosis.This article reviews the relevant literature of giant retrosternal goiter immunohisto-chemistry and shows that giant retrosternal goiter is positive for Tg,TTF-1,and Ki-67.展开更多
BACKGROUND Melioidosis,an infectious disease caused by Burkholderia pseudomallei(B.pseudomallei),occurs endemically in Southeast Asia and Northern Australia and is a serious opportunistic infection associated with a h...BACKGROUND Melioidosis,an infectious disease caused by Burkholderia pseudomallei(B.pseudomallei),occurs endemically in Southeast Asia and Northern Australia and is a serious opportunistic infection associated with a high mortality rate.CASE SUMMARY A 58-year-old woman presented with scattered erythema on the skin of her limbs,followed by fever and seizures.B.pseudomallei was isolated successively from the patient’s urine,blood,and pus.Magnetic resonance imaging showed abscess formation involving the right forehead and the right frontal region.Subsequently,abscess resection and drainage were performed.The patient showed no signs of relapse after 4 months of follow-up visits post-treatment.CONCLUSION We present here a unique case of multi-systemic melioidosis that occurs in nonendemic regions in a patient who had no recent travel history.Hence,it is critical to enhance awareness of melioidosis in non-endemic regions.展开更多
The scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally used.However,recent inventories in secondary tropical mountain forests using tradition...The scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally used.However,recent inventories in secondary tropical mountain forests using traditional biodiversity indices have yielded results that are indistinct with primary ones.This shows the need to develop complementary indices that goes beyond species count but integrates the distribution and conservation status of the species.This study developed endemicity and conservation importance index for tropical forest that incorporated the distribution and conservation status of the species.These indices were applied to Mt.Natoo,a remnant primary mossy forest in Buguias,Benguet,Philippines,that resulted to endemicity index of 81.07 and conservation importance index of 42.90.Comparing these with secondary forest sites with comparable Shannon-Wiener,Simpson,Evenness and Margalef’s indices,our endemicity and conservation indices clearly differentiates primary forest(our study site)with higher values from secondary forests with much lower values.Thus,we are proposing these indices for a direct but scientifically-informed identification of specific sites for conservation and protection in tropical forests.Additionally,our study documented a total of 168 vascular plant species(79 endemic and 12 locally threatened species)in Mt.Nato-o.Majority are of tropical elements for both generic and species levels with some temperate elements that could be attributed to the site's high elevation and semi-temperate climate.These are important baseline information for conservation plans and monitoring of tropical mossy forests.展开更多
Mosquito-borne infections are of global health concern because of their rapid spread and upsurge,which creates a risk for coinfections.chikungunya virus(CHIKV),an arbovirus disease transmitted by Aedes aegypti or A.al...Mosquito-borne infections are of global health concern because of their rapid spread and upsurge,which creates a risk for coinfections.chikungunya virus(CHIKV),an arbovirus disease transmitted by Aedes aegypti or A.albopictus,and malaria,a parasitic disease transmitted by Anopheles gambiae,are prevalent in Nigeria and neighbouring countries,but their burden and possible coinfections are poorly understood.In this study,we investigated the antibody seropositivity and endemicity of chikungunya and Zika viruses(ZIKV)in three regions of Nigeria.A cross-sectional serosurvey was conducted on 871 participants.Samples were collected from outpatients by simple random sampling.Analyses of the samples were performed using recomLine Tropical Fever for the presence of antibody serological marker IgG immunoblot with CHIKV VLP(virus like particle),ZIKV NS1 and ZIKV Equad according to manufacturers’instructions and malaria RDT for malaria parasite.There was a significantly higher antibody seropositivity against CHIKV in the central region than in the northern and southern regions(69.5%,291/419),while ZIKV-seropositivity(22.4%,34/152)and CHIKV-ZIKV co-circulating antibody seropositivity(17.8%,27/152)were notably higher in the southern region than in the central and northern regions.This investigation revealed an unexpectedly high antibody seropositivity and concealed endemicity of CHIKV and ZIKV in three Nigerian regions.The seropositivity of detectable antibodies differed among the three geographical locations.展开更多
Approximately 25%of goiters extend to the substernal area,and most of them can be removed through a cervical incision.Goiters that extend into the posterior mediastinum are very rare,and resection usually requires tho...Approximately 25%of goiters extend to the substernal area,and most of them can be removed through a cervical incision.Goiters that extend into the posterior mediastinum are very rare,and resection usually requires thoracotomy.In recent years,there have been several reports of resection of substernal goiters by minimally invasive surgery.Here,we present a 75-year-old female with a giant substernal goiter who successfully underwent resection of the goiter extending to the posterior mediastinum using low cervical incision combined with video-assisted thoracoscopy.展开更多
As important drugs for the treatment of nodular goiter(NG),Prunella Spica preparations are widely used clinically,and have a significant effect on NG.Various active ingredients in the preparations intervene in the for...As important drugs for the treatment of nodular goiter(NG),Prunella Spica preparations are widely used clinically,and have a significant effect on NG.Various active ingredients in the preparations intervene in the formation of NG by inhibiting the proliferation of thyroid follicular cells,promoting cell apoptosis,regulating immunity,improving the microcirculation of thyroid tissue and other mechanisms,and can reduce the postoperative recurrence of NG.展开更多
Medicinal plants provide crucial ecosystem services,especially in developing countries such as China,which harbors diverse endemic medicinal plant species with substantial cultural and economic value.Accordingly,under...Medicinal plants provide crucial ecosystem services,especially in developing countries such as China,which harbors diverse endemic medicinal plant species with substantial cultural and economic value.Accordingly,understanding the patterns and drivers of medicinal plant distribution is critical.However,few studies have investigated the patterns and drivers of endemic medicinal plants distribution in China.Here,we linked endemic medicinal plants distribution with possible explanatory variables,i.e.,paleoclimate change,contemporary climate,altitudinal range and ethnic minority human population size at the prefecture city level in China.Our results show that endemic medicinal plants are concentrated in southern China,especially in southwestern China.Notably,both endemic medicinal plant species richness and the ratio of endemic medicinal plant species richness are negatively associated with glacialinterglacial anomaly in temperature,and positively associated with contemporary precipitation and altitudinal range.In addition,we found that endemic medicinal plant species richness is positively associated with ethnic minority population sizes as well as its ratio to the overall population size.These findings suggest that the distribution of endemic medicinal plants is determined by multiple drivers.Furthermore,our findings stress that dramatic future climate changes and massive anthropogenic activities in southern China pose great challenges to the conservation of China's endemic medicinal plants.展开更多
Objective:To explore the mechanism of Huatan Sanjie Fang(HTSJ)in regulating goiter in Graves'disease(GD)mice by detecting key factors of the Hippo signaling pathway.Methods:A mouse model of GD was established by i...Objective:To explore the mechanism of Huatan Sanjie Fang(HTSJ)in regulating goiter in Graves'disease(GD)mice by detecting key factors of the Hippo signaling pathway.Methods:A mouse model of GD was established by injecting Ad-TSHR289 adenovirus into the bilateral quadriceps femoris of female mice.Successful mouse models were then randomly divided into a model group,methimazole(MMI)group,and HTSJ group,and fed with deionized water,MMI(4.5 mg/kg per day),and HTSJ(35.10 g/kg per day),respectively,for 10 weeks.Histopathological changes of the thyroid gland were subsequently observed by hematoxylin-eosin staining.Radioimmunoassay was used to detect serum total thyroxine(T4)and thyrotrophin-receptor antibody(TRAb)levels.The relative expression of mRNA of Mst1,YAP,and TAZ were detected by quantitative real-time polymerase chain reaction,while the protein expression of Mst1,YAP,TAZ,pMst1,and pYAP were detected by western blot.Results:After 10 weeks of drug intervention,goiter and other pathological changes in the HTSJ group significantly improved compared with the model group,and the levels of serum T4 and TRAb significantly decreased(P=.002,P<.001,respectively).Decreased mRNA expression of Mst1,YAP,and TAZ,the key factors of the Hippo signaling transduction pathway,was also observed(P=.002,P=.022,P<.001,respectively).In contrast,protein expression of Mst1(P=.046),pMst1(P=.026),and p YAP(P=.004)increased,while protein expression of YAP and TAZ decreased(P=.041,P<.001,respectively).Conclusion:HTSJ can effectively improve goiter in GD mice through the Hippo signaling pathway.展开更多
Objective:To estimate the risk of chronic kidney disease in patients with leptospirosis.Methods:All reported(41890)and later confirmed leptospirosis(1990)cases from 2010-2020 were traced by universal sampling.386 Labo...Objective:To estimate the risk of chronic kidney disease in patients with leptospirosis.Methods:All reported(41890)and later confirmed leptospirosis(1990)cases from 2010-2020 were traced by universal sampling.386 Laboratory-confirmed leptospirosis cases were enrolled and 413 age,gender,area,and occupation matched healthy persons were included as controls.Variables including socio-demographic characteristics,medical history,and health-related behaviours were compared between the two groups and association between these variables and reduced estimated glomerular filtration rate(eGFR)was analyzed with multiple linear regression.Results:The median of eGFR was 49.0(27.0,75.0)mL/min/1.73 m^(2) in the cases and 96.0(72.0,121.0)mL/min/1.73 m^(2) in the controls,showing significant differences(P<0.001).Bivariate analysis showed that leptospirosis seropositivitiy,repeat leptospirosis infection,diabetes,male gender,working in field(sun exposure),COVID-19 infection and smoking had statistically significant association with reduced eGFR.Leptospirosis seropositivity had negative effects on eGFR.Multiple linear regression confirmed that leptospirosis seropositivity had negative effects on eGFR(unstandardised β coefficients=−30.86,95%CI−49.7 to−11.9,P<0.001).Conclusions:Chronic kidney disease is a complex disease with multiple risk factors involved.Exposure to leptospirosis is one of the essential factors in accelerating its progression.展开更多
We describe a unique new species and genus of agamid lizard from the karstic massifs of Khammouan Province,central Laos.Laodracon carsticola Gen.et sp.nov.is an elusive medium-sized lizard(maximum snout-vent length101...We describe a unique new species and genus of agamid lizard from the karstic massifs of Khammouan Province,central Laos.Laodracon carsticola Gen.et sp.nov.is an elusive medium-sized lizard(maximum snout-vent length101 mm)specifically adapted to life on limestone rocks and pinnacles.To assess the phylogenetic position of the new genus amongst other agamids,we generated DNA sequences from two mitochondrial gene fragments(16S rRNA and ND2)and three nuclear loci(BDNF,RAG1 and c-mos),with a final alignment comprising 7418 base pairs for 64 agamid species.Phylogenetic analyses unambiguously place the new genus in the mainland Asia subfamily Draconinae,where it forms a clade sister to the genus Diploderma from East Asia and the northern part of Southeast Asia.Morphologically,the new genus is distinguished from all other genera in Draconinae by possessing a notably swollen tail base with enlarged scales on its dorsal and ventral surfaces.Our work provides further evidence that limestone regions of Indochina represent unique“arks of biodiversity”and harbor numerous relict lineages.To date,Laodracon carsticola Gen.et sp.nov.is known from only two adult male specimens and its distribution seems to be restricted to a narrow limestone massif on the border of Khammouan and Bolikhamxai provinces of Laos.Additional studies are required to understand its life history,distribution,and conservation status.展开更多
Objective We aimed to evaluate goiter prevalence and iodine nutritional status in areas with high levels of water iodine; to monitor the prevalence of iodine deficiency disorders (IDD) in areas at high risk of IDD; ...Objective We aimed to evaluate goiter prevalence and iodine nutritional status in areas with high levels of water iodine; to monitor the prevalence of iodine deficiency disorders (IDD) in areas at high risk of IDD; and to compare the prevalence of goiter and urine iodine (UI) concentrations between children living in the two areas. Methods Based on surveillance from 2012-2014, we analyzed the concentration of UI and prevalence of goiter in 8-10-year-old children from 12 high-risk IDD provinces, and from 8 provinces and municipalities with excessive water iodine. We calculated goiter prevalence for each UI level according to World Health Organization (WHO) standards and constructed predictive prevalence curves. Results The goiter prevalence and median UI of children from areas with high water iodine were not optimal, being above the WHO standards (5% and 100-199 μg/L, respectively), whereas those in high-risk areas fell within the standard. UI and goiter prevalence exhibited a U-shaped relationship in high-risk endemic areas and a parabolic relationship in areas of iodine excess. Conclusion Iodine surplus in high-iodine areas leads to high goiter prevalence and UI. However, in high-risk areas, UI was optimal and goiter prevalence met the national criteria for IDD elimination.展开更多
Background: Multinodular goiter is a relatively common thyroid disorder with a marked female preponderance. Most of these goiters weigh less than 100 grams with those weighing more than 500 grams being exceptional. Th...Background: Multinodular goiter is a relatively common thyroid disorder with a marked female preponderance. Most of these goiters weigh less than 100 grams with those weighing more than 500 grams being exceptional. The massively expanding goiter due to the strategic anatomic location of thyroid gland, in addition to being cosmetically disfiguring can seriously compromise the patency of the trachea and oesophagus. Thyroidectomy for such goiters is a surgical challenge due to the possible association of tracheomalacia, retrosternal extension, skin involvement and the difficulty in intubation and dissection of the thyroid gland due to distorted and displaced anatomy. Material and methods: While presenting 2 patients who underwent thyroidectomy for glands weighing more than 500 grams, the literature is reviewed to analyze the technical difficulties and approach in such patients and the frequently encountered complications in them and their management. Results: A review of the literature revealed an additional 7 cases of patients who had undergone thyroidectomy for glands weighing more than 500 grams. Massively enlarged goiter was often associated with tracheomalacia, tracheal stenosis and retrosternal extension. Difficulty during surgery was most often encountered in establishing the airway and in exposure of the gland particularly when the skin was involved. The predominant postoperative complications were related to respiratory distress as a consequence of tracheomalacia and tracheal stenosis. Conclusion: In spite of the technical challenge related to the airway, and thyroidectomy, surgery continues to be the best option in experienced hands due to its distinct advantage of its immediate effect and complete resolution of compressive symptoms.展开更多
Intrathoracic goiter(IG) is commonly located in the anterior mediastinum. Here, we report the case of a 54-year-old Chinese woman with successful removal of an intrathoracic goiter and improvement of dyspnea by a righ...Intrathoracic goiter(IG) is commonly located in the anterior mediastinum. Here, we report the case of a 54-year-old Chinese woman with successful removal of an intrathoracic goiter and improvement of dyspnea by a right posterolateral thoracotomy approach. Conclusion: Posterior mediastinal thyroid goiter with mediastinal compressive symptoms is an indication for surgery.展开更多
Background:Geographical distribution of endemic species and its multiple scale drivers are an important topic in biodiversity conservation,because these species are especially vulnerable to climate change and habitat ...Background:Geographical distribution of endemic species and its multiple scale drivers are an important topic in biodiversity conservation,because these species are especially vulnerable to climate change and habitat degradation,and therefore have high conservation priority.Here,for the first time,we simultaneously linked glacial-interglacial climate change,contemporary climate,plant species richness and altitudinal range with endemic bird distribution in China.Methods:Ordinary least squares models and simultaneous autoregressive models were used to assess the associations between endemic bird richness,endemic bird ratio and each explanatory variable.Structural Equation Models were also performed to test the direct and indirect effects of these variables on endemic bird richness and endemic bird ratio.Results:Higher endemic bird richness and endemic bird ratio occurred in regions with stable glacial-interglacial temperature,i.e.,southwest China.Plant species richness and altitudinal range were also positively correlated with endemic bird richness and endemic bird ratio.Glacial-interglacial temperature change,contemporary precipitation,plant species richness and altitudinal range were all included in the best combination of variables for endemic bird richness.Importantly,glacial-interglacial temperature change had strong direct effects on both endemic bird richness and endemic bird ratio,while plant species richness only had a direct effect on endemic bird richness.Conclusions:Our results indicate that endemic birds in China concentrate in southwest regions where there are stable glacial-interglacial temperature,more plant species and larger altitudinal range.Notably,while stable climate has strong direct effects on both endemic bird richness and endemic bird ratio,plant species may affect endemic bird richness through its effect on overall bird species richness.Importantly,the recent anthropogenic activities have also significantly intensified in this region,which would pose huge challenge for biodiversity conservation in China.展开更多
We review the fossil history of seed plant genera that are now endemic to eastern Asia. Although the majority of eastern Asian endemic genera have no known fossil record at all, 54 genera, or about 9%, are reliably kn...We review the fossil history of seed plant genera that are now endemic to eastern Asia. Although the majority of eastern Asian endemic genera have no known fossil record at all, 54 genera, or about 9%, are reliably known from the fossil record. Most of these are woody (with two exceptions), and most are today either broadly East Asian, or more specifically confined to Sino-Japanese subcategory rather than being endemic to the Sino-Himalayan area. Of the "eastern Asian endemic" genera so far known from the fossil record, the majority formerly occurred in Europe and/or North America, indicating that eastern Asia served as a late Tertiary or Quaternary refugium for taxa. Hence, many of these genera may have originated in other parts of the Northern Hemisphere and expanded their ranges across continents and former sea barriers when tectonic and climatic conditions allowed, leading to their arrival in eastern Asia. Although clear evidence for paleoendemism is provided by the gymnosperms Amentotaxus, Cathaya, Cephalotaxus, Cunninghamia, Cryptomeria, Glyptostrobus, Ginkgo, Keteleeria, Metasequoia, Nothotsuga, Pseudolarix, Sciadopitys, and Taiwania, and the angiosperms Cercidiphyllum, Choerospondias, Corylopsis, Craigia, Cyclocarya, Davidia, Dipelta, Decaisnea, Diplopanax, Dipteronia, Emmenopterys, Eucommia, Euscaphis, Hemiptelea, Hovenia, Koelreuteria, Paulownia, Phellodendron, Platycarya, Pteroceltis, Rehderodendron, Sargentodoxa, Schizophragma, Sinomenium, Tapiscia, Tetracentron, Toricellia, Trapella, and Trochodendron, we cannot rule out the possibility that neoendemism plays an important role especially for herbaceous taxa in the present-day flora of Asia, particularly in the Sino-Himalayan region. In addition to reviewing paleobotanical occurrences from the literature, we document newly recognized fossil occurrences that expand the geographic and stratigraphic ranges previously known for Dipelta, Pteroceltis, and Toricellia.展开更多
Amphibians are good indicators of ecosystem health. Updating the information of endemic species in time and understanding their spatial distributions are necessary for the development of integrative conservation strat...Amphibians are good indicators of ecosystem health. Updating the information of endemic species in time and understanding their spatial distributions are necessary for the development of integrative conservation strategies and the elucidation of geographic patterns of amphibians. We analyzed the diversity and distributions of the endemic amphibians in China based on a database of specimen records, recently published literature, and field surveys. Two hundred and sixty two endemic species of amphibians, belonging to 59 genera in 12 families and two orders, are recognized. They account for 67% of the total number of amphibian species in China, with the family Megophryidae possessing the largest number of endemics. There are also 17 genera endemic to China. Across provinces, the species richness of endemics shows five levels with a hierarchical diversification. Sichuan has the largest number of endemics, while Heilongjiang and Jilin have no endemic species. Alternatively, whether on the level of endemic genus or species, the highest diversity occurs in the Western Mountains and Plateau Subregion. The distribution ranges of most endemic species cover ≤ 4 provinces or zoogeographic subregions. Additionally, the species richness of endemics along an elevational gradient shows a bell-shaped pattern with the peak around 800 m. Most endemic species are distributed in areas of low to mid elevation(c. 700–1 500 m), while 36 species are distributed up to 3 000 m. Endemic species richness decreases with increasing of elevation range. Species at mid elevations display large range sizes, while species at lower and higher elevations exhibit smaller ranges. Our results are to be beneficial for further exploration of the underlying mechanisms of distributional patterns of amphibians in China. This study highlights a need to promote conservation programs for Chinese endemic amphibians due to their narrow distribution ranges and potential threats.展开更多
This paper deals with some endemic diseases related to selenium, iodine and fluoride in eco-environment. Keshan disease and Kaschin-Beck disease are associated with low selenium, they mainly occur in a belt zone acros...This paper deals with some endemic diseases related to selenium, iodine and fluoride in eco-environment. Keshan disease and Kaschin-Beck disease are associated with low selenium, they mainly occur in a belt zone across China ranging from North-East to South-West. Selenium contents in food grains and human hair from the disease affected areas are usually below 0.020ppm and 0.20ppm respectively. The endemic goitre caused by iodine deficiency distributes extensively in China, mainly in mountainous and hilly districts, swamp and peat areas, some sand soil and limestone areas. Also there is another kind of endemic goitre which caused by iodine excess in interior and coast areas. Endemic cretinism usually occurs in the endemic goitre seriously affected areas. Endemic fluorosis is also widely distributed in China, but mainly occurs in dry or semi-dry areas of north China. The fluoride sources for causing endemic fluorisis are drinking water and food grains polluted by coal smoke in the backing process of maize and chilli.展开更多
Cupressus atlantica Gaussen (Cupressaceae) is an endemic and endangered coniferous tree geographically restricted to the N'Fis valley in South-Western Morocco. Like many forest species, C. atlantica exhibits dorman...Cupressus atlantica Gaussen (Cupressaceae) is an endemic and endangered coniferous tree geographically restricted to the N'Fis valley in South-Western Morocco. Like many forest species, C. atlantica exhibits dormancy which delays and reduces germination. To improve seed germination, different pre-treatments were conducted on C. atlantica seeds after storage for different periods (one, two and five years) including: scarification with sandy paper; soaking seeds in hot distilled water at 60℃ and 80℃ for 15 min and soaking seeds for 48 h in a gibberellic acid (GA3) at 1,000 and 2,000 mg·L-1. Results showed that scarification with sandy paper increased the germination rate of Atlas cypress by up to 67%, indicating that the species possess essentially an exogenous dormancy (physical dormancy) due to the hard seed coat (hardseededness). Exogenous application of gibberellic acid (GA3) at 1,000 mg.L-1 was also effective in breaking seed dormancy and germination induction. These two treatments induced faster speed germination expressed by low number of days to first germination (8-10 days) and low values of mean germination times (MGT). However, germination rate, under any treatment, is greatly dependent on the year of seed collection. Seeds collected in year 2004 gave the highest value, suggesting that even after five years of storage, the germination capacity of C. atlantica seeds could remain high. This observation is very interesting in the ex-situ conservation of such endemic and endangered species where the production of seeds is irregular over the years.展开更多
With the accumulation and accessibility of information about plant species,it is time to re-evaluate and further divide a global biodiversity hotspot region,Yunnan,located in southwestern China.In this study,we combin...With the accumulation and accessibility of information about plant species,it is time to re-evaluate and further divide a global biodiversity hotspot region,Yunnan,located in southwestern China.In this study,we combined data on the distribution of 1010 stenochoric endemic seed plants,vegetation constitution,geological history and climate change,and used these to propose a new system of floristic regions.We identified 11 distinct floristic subregions and 84 floristic provinces within Yunnan.Our work confirmed some views emphasized by Wu Zhengyi that the stenochoric endemic species play a key role in defining floristic provinces;that stenochoric endemic plants with long collection and publication histories are more valuable;that greater attention should be paid to woody plants;and that for Yunnan,a border region,some trans-border distributed elements should be treated cautiously.展开更多
文摘Thyroid gland is one of most important endocrine glands in the body. It plays vital role in growth control and its measurements tends to change in respect to age, sex, weight and ethnic group of the individual. This study aimed to assess endemic goiter and to estimate the measurement of normal thyroid gland dimensions and thyroid hormones level in school-aged children using Ultrasonography and ELISA Technique in Eastern Sudan (Kassala state). A total of 100 subjects is 6 - 18 years (43 males, 57 females), and mean of age (9.73 ± 2.54 years). This study was done in the period from April 2016 to February 2017. All the subject undergone thyroid ultrasound and thyroid hormone level test. Subjects with history of goiter were excluded from the study, by thyroid dimension (length, height and diameter). Thyroid volume was estimated using ellipsoid formula and thyroid hormones (TSH, T3 and T4) using Toso full automation. The study revealed that 12 subjects of the study (12%) with goiter, 7 female (7%) and 5 males (5%) with age ranged 6 - 11 years with increase in TSH and T3 and decrease in T4 level. The mean of thyroid volumes for normal subject and subject of goiter are 4.93 ± 0.63, 5.4 ± 1.4 mL, respectively, and TSH, T3, T4 (1.8 ± 0.97, 2.4 ± 0.86 UIu/nL), (3.61 ± 0.32, 3.8 ± 0.55 Pg/Nl), (1.35 ± 1.23 ng/DI level respectively). It concluded that there was positive correlations between the age and the thyroid volume (p = 0.65). It increases with increase of the age. The Rt lobe is larger than the Lt lobe;the thyroid volume is higher in male than female, and this study found the TSH and T3 decreased with ages while T4 increased with ages in normal subject;TSH and T3 level increased and T4 level decreased in goiter children.
基金Supported by the Scientific Research Foundation of Peking University Shenzhen Hospital,No.KYQD202100Xthe National Natural Science Foundation of China,No.81972829and Precision Medicine Research Program of Tsinghua University,No.2022ZLA006。
文摘BACKGROUND Elderly giant retrosternal thyroid goiter is a rare yet significant medical condition,often presenting clinical symptoms that can be confused with other diseases,posing diagnostic and therapeutic challenges.This study aims to delve into the characteristics and potential mechanisms of this ailment through pathological diagnosis and immunohistochemical analysis,providing clinicians with more precise diagnostic and treatment strategies.A 77-year-old male,was admitted to hospital with the chief complaint of finding a goiter in the semilunar month during physical examination,accompanied by dyspnea.Locally protruding into the superior mediastinum,the adjacent structure was compressed,the trachea was compressed to the right,and the local lumen was slightly narrowed.The patient was diagnosed with giant retrosternal goiter.Considering dyspnea caused by trachea compression,our department planned to perform giant retrosternal thyroidectomy.Immunohistochemical results:Tg(+),TTF-1(+),Calcitonin(CT)(I),Ki-67(+,about 20%),CD34(-).Retrosternal goiter means that more than 50%of the volume of the thyroid gland is below the upper margin of the sternum.As retrosternal goiter disease is a relatively rare disease,once the disease is diagnosed,it should be timely surgical treatment,and the treatment is more difficult,the need for professional medical team for comprehensive treatment.CONCLUSION The imaging manifestations of giant retrosternal goiter are atypical,histomorphology and immunohistochemistry can assist in its diagnosis.This article reviews the relevant literature of giant retrosternal goiter immunohisto-chemistry and shows that giant retrosternal goiter is positive for Tg,TTF-1,and Ki-67.
文摘BACKGROUND Melioidosis,an infectious disease caused by Burkholderia pseudomallei(B.pseudomallei),occurs endemically in Southeast Asia and Northern Australia and is a serious opportunistic infection associated with a high mortality rate.CASE SUMMARY A 58-year-old woman presented with scattered erythema on the skin of her limbs,followed by fever and seizures.B.pseudomallei was isolated successively from the patient’s urine,blood,and pus.Magnetic resonance imaging showed abscess formation involving the right forehead and the right frontal region.Subsequently,abscess resection and drainage were performed.The patient showed no signs of relapse after 4 months of follow-up visits post-treatment.CONCLUSION We present here a unique case of multi-systemic melioidosis that occurs in nonendemic regions in a patient who had no recent travel history.Hence,it is critical to enhance awareness of melioidosis in non-endemic regions.
文摘The scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally used.However,recent inventories in secondary tropical mountain forests using traditional biodiversity indices have yielded results that are indistinct with primary ones.This shows the need to develop complementary indices that goes beyond species count but integrates the distribution and conservation status of the species.This study developed endemicity and conservation importance index for tropical forest that incorporated the distribution and conservation status of the species.These indices were applied to Mt.Natoo,a remnant primary mossy forest in Buguias,Benguet,Philippines,that resulted to endemicity index of 81.07 and conservation importance index of 42.90.Comparing these with secondary forest sites with comparable Shannon-Wiener,Simpson,Evenness and Margalef’s indices,our endemicity and conservation indices clearly differentiates primary forest(our study site)with higher values from secondary forests with much lower values.Thus,we are proposing these indices for a direct but scientifically-informed identification of specific sites for conservation and protection in tropical forests.Additionally,our study documented a total of 168 vascular plant species(79 endemic and 12 locally threatened species)in Mt.Nato-o.Majority are of tropical elements for both generic and species levels with some temperate elements that could be attributed to the site's high elevation and semi-temperate climate.These are important baseline information for conservation plans and monitoring of tropical mossy forests.
文摘Mosquito-borne infections are of global health concern because of their rapid spread and upsurge,which creates a risk for coinfections.chikungunya virus(CHIKV),an arbovirus disease transmitted by Aedes aegypti or A.albopictus,and malaria,a parasitic disease transmitted by Anopheles gambiae,are prevalent in Nigeria and neighbouring countries,but their burden and possible coinfections are poorly understood.In this study,we investigated the antibody seropositivity and endemicity of chikungunya and Zika viruses(ZIKV)in three regions of Nigeria.A cross-sectional serosurvey was conducted on 871 participants.Samples were collected from outpatients by simple random sampling.Analyses of the samples were performed using recomLine Tropical Fever for the presence of antibody serological marker IgG immunoblot with CHIKV VLP(virus like particle),ZIKV NS1 and ZIKV Equad according to manufacturers’instructions and malaria RDT for malaria parasite.There was a significantly higher antibody seropositivity against CHIKV in the central region than in the northern and southern regions(69.5%,291/419),while ZIKV-seropositivity(22.4%,34/152)and CHIKV-ZIKV co-circulating antibody seropositivity(17.8%,27/152)were notably higher in the southern region than in the central and northern regions.This investigation revealed an unexpectedly high antibody seropositivity and concealed endemicity of CHIKV and ZIKV in three Nigerian regions.The seropositivity of detectable antibodies differed among the three geographical locations.
基金supported by the Fundamental Research Funds for the Central Universities(2021FZZX005-21).
文摘Approximately 25%of goiters extend to the substernal area,and most of them can be removed through a cervical incision.Goiters that extend into the posterior mediastinum are very rare,and resection usually requires thoracotomy.In recent years,there have been several reports of resection of substernal goiters by minimally invasive surgery.Here,we present a 75-year-old female with a giant substernal goiter who successfully underwent resection of the goiter extending to the posterior mediastinum using low cervical incision combined with video-assisted thoracoscopy.
基金Supported by the Key Project of Teaching Reform Research of Taishan Vocational College of Nursing(202307).
文摘As important drugs for the treatment of nodular goiter(NG),Prunella Spica preparations are widely used clinically,and have a significant effect on NG.Various active ingredients in the preparations intervene in the formation of NG by inhibiting the proliferation of thyroid follicular cells,promoting cell apoptosis,regulating immunity,improving the microcirculation of thyroid tissue and other mechanisms,and can reduce the postoperative recurrence of NG.
基金supported by National Natural Science Foundation of China(31870506)Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB31000000)+1 种基金supported by the the National Key R&D Program of China(2019YFA0607103)the National Natural Science Foundation of China(41861004).
文摘Medicinal plants provide crucial ecosystem services,especially in developing countries such as China,which harbors diverse endemic medicinal plant species with substantial cultural and economic value.Accordingly,understanding the patterns and drivers of medicinal plant distribution is critical.However,few studies have investigated the patterns and drivers of endemic medicinal plants distribution in China.Here,we linked endemic medicinal plants distribution with possible explanatory variables,i.e.,paleoclimate change,contemporary climate,altitudinal range and ethnic minority human population size at the prefecture city level in China.Our results show that endemic medicinal plants are concentrated in southern China,especially in southwestern China.Notably,both endemic medicinal plant species richness and the ratio of endemic medicinal plant species richness are negatively associated with glacialinterglacial anomaly in temperature,and positively associated with contemporary precipitation and altitudinal range.In addition,we found that endemic medicinal plant species richness is positively associated with ethnic minority population sizes as well as its ratio to the overall population size.These findings suggest that the distribution of endemic medicinal plants is determined by multiple drivers.Furthermore,our findings stress that dramatic future climate changes and massive anthropogenic activities in southern China pose great challenges to the conservation of China's endemic medicinal plants.
基金supported by the National Natural Science Fund(82004337)the Beijing University of Chinese Medicine new teacher launch fund(2020-JYB-XJSJJ-002)。
文摘Objective:To explore the mechanism of Huatan Sanjie Fang(HTSJ)in regulating goiter in Graves'disease(GD)mice by detecting key factors of the Hippo signaling pathway.Methods:A mouse model of GD was established by injecting Ad-TSHR289 adenovirus into the bilateral quadriceps femoris of female mice.Successful mouse models were then randomly divided into a model group,methimazole(MMI)group,and HTSJ group,and fed with deionized water,MMI(4.5 mg/kg per day),and HTSJ(35.10 g/kg per day),respectively,for 10 weeks.Histopathological changes of the thyroid gland were subsequently observed by hematoxylin-eosin staining.Radioimmunoassay was used to detect serum total thyroxine(T4)and thyrotrophin-receptor antibody(TRAb)levels.The relative expression of mRNA of Mst1,YAP,and TAZ were detected by quantitative real-time polymerase chain reaction,while the protein expression of Mst1,YAP,TAZ,pMst1,and pYAP were detected by western blot.Results:After 10 weeks of drug intervention,goiter and other pathological changes in the HTSJ group significantly improved compared with the model group,and the levels of serum T4 and TRAb significantly decreased(P=.002,P<.001,respectively).Decreased mRNA expression of Mst1,YAP,and TAZ,the key factors of the Hippo signaling transduction pathway,was also observed(P=.002,P=.022,P<.001,respectively).In contrast,protein expression of Mst1(P=.046),pMst1(P=.026),and p YAP(P=.004)increased,while protein expression of YAP and TAZ decreased(P=.041,P<.001,respectively).Conclusion:HTSJ can effectively improve goiter in GD mice through the Hippo signaling pathway.
文摘Objective:To estimate the risk of chronic kidney disease in patients with leptospirosis.Methods:All reported(41890)and later confirmed leptospirosis(1990)cases from 2010-2020 were traced by universal sampling.386 Laboratory-confirmed leptospirosis cases were enrolled and 413 age,gender,area,and occupation matched healthy persons were included as controls.Variables including socio-demographic characteristics,medical history,and health-related behaviours were compared between the two groups and association between these variables and reduced estimated glomerular filtration rate(eGFR)was analyzed with multiple linear regression.Results:The median of eGFR was 49.0(27.0,75.0)mL/min/1.73 m^(2) in the cases and 96.0(72.0,121.0)mL/min/1.73 m^(2) in the controls,showing significant differences(P<0.001).Bivariate analysis showed that leptospirosis seropositivitiy,repeat leptospirosis infection,diabetes,male gender,working in field(sun exposure),COVID-19 infection and smoking had statistically significant association with reduced eGFR.Leptospirosis seropositivity had negative effects on eGFR.Multiple linear regression confirmed that leptospirosis seropositivity had negative effects on eGFR(unstandardised β coefficients=−30.86,95%CI−49.7 to−11.9,P<0.001).Conclusions:Chronic kidney disease is a complex disease with multiple risk factors involved.Exposure to leptospirosis is one of the essential factors in accelerating its progression.
基金supported by the Russian Science Foundation(22-14-00037)to N.A.P.(phylogenetic analyses)National Natural Science Foundation of China(32130015)to K.W.(data collection)partially by Rufford Foundation(39897-1) to N.T.V.(data collection)。
文摘We describe a unique new species and genus of agamid lizard from the karstic massifs of Khammouan Province,central Laos.Laodracon carsticola Gen.et sp.nov.is an elusive medium-sized lizard(maximum snout-vent length101 mm)specifically adapted to life on limestone rocks and pinnacles.To assess the phylogenetic position of the new genus amongst other agamids,we generated DNA sequences from two mitochondrial gene fragments(16S rRNA and ND2)and three nuclear loci(BDNF,RAG1 and c-mos),with a final alignment comprising 7418 base pairs for 64 agamid species.Phylogenetic analyses unambiguously place the new genus in the mainland Asia subfamily Draconinae,where it forms a clade sister to the genus Diploderma from East Asia and the northern part of Southeast Asia.Morphologically,the new genus is distinguished from all other genera in Draconinae by possessing a notably swollen tail base with enlarged scales on its dorsal and ventral surfaces.Our work provides further evidence that limestone regions of Indochina represent unique“arks of biodiversity”and harbor numerous relict lineages.To date,Laodracon carsticola Gen.et sp.nov.is known from only two adult male specimens and its distribution seems to be restricted to a narrow limestone massif on the border of Khammouan and Bolikhamxai provinces of Laos.Additional studies are required to understand its life history,distribution,and conservation status.
文摘Objective We aimed to evaluate goiter prevalence and iodine nutritional status in areas with high levels of water iodine; to monitor the prevalence of iodine deficiency disorders (IDD) in areas at high risk of IDD; and to compare the prevalence of goiter and urine iodine (UI) concentrations between children living in the two areas. Methods Based on surveillance from 2012-2014, we analyzed the concentration of UI and prevalence of goiter in 8-10-year-old children from 12 high-risk IDD provinces, and from 8 provinces and municipalities with excessive water iodine. We calculated goiter prevalence for each UI level according to World Health Organization (WHO) standards and constructed predictive prevalence curves. Results The goiter prevalence and median UI of children from areas with high water iodine were not optimal, being above the WHO standards (5% and 100-199 μg/L, respectively), whereas those in high-risk areas fell within the standard. UI and goiter prevalence exhibited a U-shaped relationship in high-risk endemic areas and a parabolic relationship in areas of iodine excess. Conclusion Iodine surplus in high-iodine areas leads to high goiter prevalence and UI. However, in high-risk areas, UI was optimal and goiter prevalence met the national criteria for IDD elimination.
文摘Background: Multinodular goiter is a relatively common thyroid disorder with a marked female preponderance. Most of these goiters weigh less than 100 grams with those weighing more than 500 grams being exceptional. The massively expanding goiter due to the strategic anatomic location of thyroid gland, in addition to being cosmetically disfiguring can seriously compromise the patency of the trachea and oesophagus. Thyroidectomy for such goiters is a surgical challenge due to the possible association of tracheomalacia, retrosternal extension, skin involvement and the difficulty in intubation and dissection of the thyroid gland due to distorted and displaced anatomy. Material and methods: While presenting 2 patients who underwent thyroidectomy for glands weighing more than 500 grams, the literature is reviewed to analyze the technical difficulties and approach in such patients and the frequently encountered complications in them and their management. Results: A review of the literature revealed an additional 7 cases of patients who had undergone thyroidectomy for glands weighing more than 500 grams. Massively enlarged goiter was often associated with tracheomalacia, tracheal stenosis and retrosternal extension. Difficulty during surgery was most often encountered in establishing the airway and in exposure of the gland particularly when the skin was involved. The predominant postoperative complications were related to respiratory distress as a consequence of tracheomalacia and tracheal stenosis. Conclusion: In spite of the technical challenge related to the airway, and thyroidectomy, surgery continues to be the best option in experienced hands due to its distinct advantage of its immediate effect and complete resolution of compressive symptoms.
文摘Intrathoracic goiter(IG) is commonly located in the anterior mediastinum. Here, we report the case of a 54-year-old Chinese woman with successful removal of an intrathoracic goiter and improvement of dyspnea by a right posterolateral thoracotomy approach. Conclusion: Posterior mediastinal thyroid goiter with mediastinal compressive symptoms is an indication for surgery.
基金supported by the National Natural Science Foundation of China(No.41861004 granted to GF,and 31870506 to ML)the Inner Mongolia Grassland Talent(12000-12102228 to GF)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB31000000 granted to ML)Natural Science Foundation of Jiangsu Province(BK20181398 granted to ML)。
文摘Background:Geographical distribution of endemic species and its multiple scale drivers are an important topic in biodiversity conservation,because these species are especially vulnerable to climate change and habitat degradation,and therefore have high conservation priority.Here,for the first time,we simultaneously linked glacial-interglacial climate change,contemporary climate,plant species richness and altitudinal range with endemic bird distribution in China.Methods:Ordinary least squares models and simultaneous autoregressive models were used to assess the associations between endemic bird richness,endemic bird ratio and each explanatory variable.Structural Equation Models were also performed to test the direct and indirect effects of these variables on endemic bird richness and endemic bird ratio.Results:Higher endemic bird richness and endemic bird ratio occurred in regions with stable glacial-interglacial temperature,i.e.,southwest China.Plant species richness and altitudinal range were also positively correlated with endemic bird richness and endemic bird ratio.Glacial-interglacial temperature change,contemporary precipitation,plant species richness and altitudinal range were all included in the best combination of variables for endemic bird richness.Importantly,glacial-interglacial temperature change had strong direct effects on both endemic bird richness and endemic bird ratio,while plant species richness only had a direct effect on endemic bird richness.Conclusions:Our results indicate that endemic birds in China concentrate in southwest regions where there are stable glacial-interglacial temperature,more plant species and larger altitudinal range.Notably,while stable climate has strong direct effects on both endemic bird richness and endemic bird ratio,plant species may affect endemic bird richness through its effect on overall bird species richness.Importantly,the recent anthropogenic activities have also significantly intensified in this region,which would pose huge challenge for biodiversity conservation in China.
基金supported in part by US National Science Foundation grants EAR 9220079,0174295INT 0074295 to SRM+4 种基金National Basic Research Program of China (973 Program No.2007CB411600)Chinese Academy of Sciences (KSCX2-YW-R-136) to CZDin part by Research Project of the National Museum of Nature of Science (20077005)the Monbusho Grant-in-Aid for Scientific Research (17540446) for KUsupported through SRM's participation in the NSF (NESCent)-sponsored Phytogeography of the Northern Hemisphere Working Group
文摘We review the fossil history of seed plant genera that are now endemic to eastern Asia. Although the majority of eastern Asian endemic genera have no known fossil record at all, 54 genera, or about 9%, are reliably known from the fossil record. Most of these are woody (with two exceptions), and most are today either broadly East Asian, or more specifically confined to Sino-Japanese subcategory rather than being endemic to the Sino-Himalayan area. Of the "eastern Asian endemic" genera so far known from the fossil record, the majority formerly occurred in Europe and/or North America, indicating that eastern Asia served as a late Tertiary or Quaternary refugium for taxa. Hence, many of these genera may have originated in other parts of the Northern Hemisphere and expanded their ranges across continents and former sea barriers when tectonic and climatic conditions allowed, leading to their arrival in eastern Asia. Although clear evidence for paleoendemism is provided by the gymnosperms Amentotaxus, Cathaya, Cephalotaxus, Cunninghamia, Cryptomeria, Glyptostrobus, Ginkgo, Keteleeria, Metasequoia, Nothotsuga, Pseudolarix, Sciadopitys, and Taiwania, and the angiosperms Cercidiphyllum, Choerospondias, Corylopsis, Craigia, Cyclocarya, Davidia, Dipelta, Decaisnea, Diplopanax, Dipteronia, Emmenopterys, Eucommia, Euscaphis, Hemiptelea, Hovenia, Koelreuteria, Paulownia, Phellodendron, Platycarya, Pteroceltis, Rehderodendron, Sargentodoxa, Schizophragma, Sinomenium, Tapiscia, Tetracentron, Toricellia, Trapella, and Trochodendron, we cannot rule out the possibility that neoendemism plays an important role especially for herbaceous taxa in the present-day flora of Asia, particularly in the Sino-Himalayan region. In addition to reviewing paleobotanical occurrences from the literature, we document newly recognized fossil occurrences that expand the geographic and stratigraphic ranges previously known for Dipelta, Pteroceltis, and Toricellia.
基金supported by the Knowledge Innovation Program of the Chinese Academy of Sciences(Y1B302100)to Junhua HUthe National Natural Science Foundation of China(NSFC,31071906)the Main Direction Program of the Knowledge Innovation Project of CAS(Grant No.KSCX2-EW-J-22)to Jianping JIANG
文摘Amphibians are good indicators of ecosystem health. Updating the information of endemic species in time and understanding their spatial distributions are necessary for the development of integrative conservation strategies and the elucidation of geographic patterns of amphibians. We analyzed the diversity and distributions of the endemic amphibians in China based on a database of specimen records, recently published literature, and field surveys. Two hundred and sixty two endemic species of amphibians, belonging to 59 genera in 12 families and two orders, are recognized. They account for 67% of the total number of amphibian species in China, with the family Megophryidae possessing the largest number of endemics. There are also 17 genera endemic to China. Across provinces, the species richness of endemics shows five levels with a hierarchical diversification. Sichuan has the largest number of endemics, while Heilongjiang and Jilin have no endemic species. Alternatively, whether on the level of endemic genus or species, the highest diversity occurs in the Western Mountains and Plateau Subregion. The distribution ranges of most endemic species cover ≤ 4 provinces or zoogeographic subregions. Additionally, the species richness of endemics along an elevational gradient shows a bell-shaped pattern with the peak around 800 m. Most endemic species are distributed in areas of low to mid elevation(c. 700–1 500 m), while 36 species are distributed up to 3 000 m. Endemic species richness decreases with increasing of elevation range. Species at mid elevations display large range sizes, while species at lower and higher elevations exhibit smaller ranges. Our results are to be beneficial for further exploration of the underlying mechanisms of distributional patterns of amphibians in China. This study highlights a need to promote conservation programs for Chinese endemic amphibians due to their narrow distribution ranges and potential threats.
文摘This paper deals with some endemic diseases related to selenium, iodine and fluoride in eco-environment. Keshan disease and Kaschin-Beck disease are associated with low selenium, they mainly occur in a belt zone across China ranging from North-East to South-West. Selenium contents in food grains and human hair from the disease affected areas are usually below 0.020ppm and 0.20ppm respectively. The endemic goitre caused by iodine deficiency distributes extensively in China, mainly in mountainous and hilly districts, swamp and peat areas, some sand soil and limestone areas. Also there is another kind of endemic goitre which caused by iodine excess in interior and coast areas. Endemic cretinism usually occurs in the endemic goitre seriously affected areas. Endemic fluorosis is also widely distributed in China, but mainly occurs in dry or semi-dry areas of north China. The fluoride sources for causing endemic fluorisis are drinking water and food grains polluted by coal smoke in the backing process of maize and chilli.
文摘Cupressus atlantica Gaussen (Cupressaceae) is an endemic and endangered coniferous tree geographically restricted to the N'Fis valley in South-Western Morocco. Like many forest species, C. atlantica exhibits dormancy which delays and reduces germination. To improve seed germination, different pre-treatments were conducted on C. atlantica seeds after storage for different periods (one, two and five years) including: scarification with sandy paper; soaking seeds in hot distilled water at 60℃ and 80℃ for 15 min and soaking seeds for 48 h in a gibberellic acid (GA3) at 1,000 and 2,000 mg·L-1. Results showed that scarification with sandy paper increased the germination rate of Atlas cypress by up to 67%, indicating that the species possess essentially an exogenous dormancy (physical dormancy) due to the hard seed coat (hardseededness). Exogenous application of gibberellic acid (GA3) at 1,000 mg.L-1 was also effective in breaking seed dormancy and germination induction. These two treatments induced faster speed germination expressed by low number of days to first germination (8-10 days) and low values of mean germination times (MGT). However, germination rate, under any treatment, is greatly dependent on the year of seed collection. Seeds collected in year 2004 gave the highest value, suggesting that even after five years of storage, the germination capacity of C. atlantica seeds could remain high. This observation is very interesting in the ex-situ conservation of such endemic and endangered species where the production of seeds is irregular over the years.
基金supported by the Biodiversity Conservation Research Project of Yunnan Environmental Protection Department (Grant no.Y430112261)
文摘With the accumulation and accessibility of information about plant species,it is time to re-evaluate and further divide a global biodiversity hotspot region,Yunnan,located in southwestern China.In this study,we combined data on the distribution of 1010 stenochoric endemic seed plants,vegetation constitution,geological history and climate change,and used these to propose a new system of floristic regions.We identified 11 distinct floristic subregions and 84 floristic provinces within Yunnan.Our work confirmed some views emphasized by Wu Zhengyi that the stenochoric endemic species play a key role in defining floristic provinces;that stenochoric endemic plants with long collection and publication histories are more valuable;that greater attention should be paid to woody plants;and that for Yunnan,a border region,some trans-border distributed elements should be treated cautiously.