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Status of the Xinjiang Ground Jay:population,breeding ecology and conservation 被引量:1
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作者 马鸣 《Chinese Birds》 2011年第1期59-62,共4页
The Xinjiang Ground Jay (Podoces biddulphi) is a bird species endemic to China. It has a restricted range, living only in the Taklimakan Desert, southern part of Xinjiang. So far, little information has been known of ... The Xinjiang Ground Jay (Podoces biddulphi) is a bird species endemic to China. It has a restricted range, living only in the Taklimakan Desert, southern part of Xinjiang. So far, little information has been known of the status and ecology of the bird in the world. Since 1988, I have been taking field investigations on the distribution, population size and breeding ecology of the Xinjiang Ground Jay in the desert.In this thesis, the desertification in relation to the eastward expansion of the ground jays was discussed. 展开更多
关键词 xinjiang Ground Jay breeding ecology population size CONsERVATION Taklimakan Desert
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Euler’s First-Order Explicit Method–Peridynamic Differential Operator for Solving Population Balance Equations of the Crystallization Process
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作者 Chunlei Ruan Cengceng Dong +2 位作者 Kunfeng Liang Zhijun Liu Xinru Bao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期3033-3049,共17页
Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridyna... Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridynamic differential operator(EE–PDDO)was obtained for solving the one-dimensional population balance equation in crystallization.Four different conditions during crystallization were studied:size-independent growth,sizedependent growth in a batch process,nucleation and size-independent growth,and nucleation and size-dependent growth in a continuous process.The high accuracy of the EE–PDDO method was confirmed by comparing it with the numerical results obtained using the second-order upwind and HR-van methods.The method is characterized by non-oscillation and high accuracy,especially in the discontinuous and sharp crystal size distribution.The stability of the EE–PDDO method,choice of weight function in the PDDO method,and optimal time step are also discussed. 展开更多
关键词 population balance equation CRYsTALLIZATION peridynamic differential operator Euler’s first-order explicit method
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Study on Resource Status and Protection Countermeasures of Wild Plant Species with Extremely Small Populations(PSESP)in Xinjiang
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作者 Li CHEN Ting NIU Xin HAN 《Meteorological and Environmental Research》 CAS 2022年第2期83-97,I0002-I0010,共24页
In recent years,the protection of PSESP has gradually become a hot issue in biodiversity research.Through the investigation and analysis of PSESP in Xinjiang,it is shown that:①there are 75 species of PSESP in Xinjian... In recent years,the protection of PSESP has gradually become a hot issue in biodiversity research.Through the investigation and analysis of PSESP in Xinjiang,it is shown that:①there are 75 species of PSESP in Xinjiang,including 22 species of trees,18 species of shrubs and 35 species of herbs.The habitats are mainly in extremely cold,extremely dry or extremely narrow conditions such as snow line,desert,mountain,wetland and so on.②53 species(70.67%)are listed as national or autonomous region protected plants,and 22 species of PSESP are not listed in the protection;there are 70 species of PSESP listed in the red list,accounting for 93.33%.③The PSESP in Xinjiang are mainly distributed in the Altai Mountains,western Tianshan Mountains,Pamir Plateau and Karakoram Mountains;they are distributed in all kinds of nature reserves,forest parks,wetland parks and other natural ecological protection areas in Xinjiang.Ammopiptanthus nanus(M.Pop.)Cheng F.,Cistanche tubulosa(Schenk)Wight,Calligonum roborovskii A.Los.and Prunus cerasifera Ehrhart have not been found in the literature,indicating that they are distributed in protected areas.In order to provide a theoretical basis for the conservation of biodiversity in Xinjiang,this paper puts forward some suggestions on the protection of PSESP. 展开更多
关键词 Wild plant species with extremely small populations(PsEsP) Resource status Protection countermeasures xinjiang
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Allozyme Diversity and Population Genetic Structure of Three Medicinal Epimedium Species from Hubei 被引量:4
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作者 徐艳琴 李作洲 +1 位作者 王瑛 黄宏文 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第1期56-71,共16页
Three Epimedium species, E. pubescens Maxim., E. sagittatum (Sieb. & Zucc.) Maxim., and E. wushanense T. S. Ying, which are sympatrically distributed in the western Hubei Province, have been used in traditional Chi... Three Epimedium species, E. pubescens Maxim., E. sagittatum (Sieb. & Zucc.) Maxim., and E. wushanense T. S. Ying, which are sympatrically distributed in the western Hubei Province, have been used in traditional Chinese medicine (TCM) for about 2,000 years. Genetic variability and population genetic structure of 11 natural populations of these Epimedium species were investigated using isoelectric focusing in thin-layer polyacrylamide slab gels. Of the 22 enzyme systems prescreened, six coding for 13 loci and 45 alleles were resolved, which were used for analyzing genetic diversity and population structure at both intraspecific and interspecific levels. The results showed that: l) high levels of genetic diversity were observed in all three species (A = 2.6-3.2, P = 69.2%-84.6%, Ho= 0.274-0.377, HE= 0.282-0.369), which were higher than that of other herbaceous and aulmal-pollinated species with similar life-history characteristics; 2) there was significant deviation from Hardy-Weinberg Equilibrium, with one half of the loci showing heterozygote excess and the other homozygote excess, in all populations, suggesting the complicated breeding system of Epimedium species; 3) the low level of intraspecific and interspecific genetic differentiation (GST= 0.0246-0.0409 and 0.0495-0.1213, respectively) indicated a high level of gene flow among populations and close genetic relationship among the three species; and 4) UPGMA cluster analysis further showed that E. pubescens was more closely related to E. sagittatum than to E. wushanense, which was in good agreement with the morphological characters and the recent phylogenetic analysis of these species. On the basis of these results, it was concluded that the mixed breeding system, long-lived perennial life form, ancient evolutionary history, and seed dispersal by ants in Epimedium are responsible for the genetic variation and population structure of these species. 展开更多
关键词 Epimedium pubescens Maxim. E. sagittatum sieb. Zucc.) Maxim. E. wushanense T. s. Ying ALLOZYME genetic diversity population structure
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Comparative Analysis of Improving Effects of 12 Maize Populations with Improved S_1 Selection Method
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作者 孙峰成 冯勇 +6 位作者 付增娟 苏二虎 张来厚 赵瑞霞 刘志雄 石海波 李美娜 《Agricultural Science & Technology》 CAS 2014年第10期1687-1692,1713,共7页
ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of... ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of grains per row and 100-grain weight were the three important component traits of maize yield. The highest genetic increment was found in Mengqun 2, fol owed by Mengqun 4, Mengqun 1 and other 7 maize populations. Negative genetic increment was shown in Mengqun 3 and 3 introduced foreign maize populations. Some changes were shown in spikes, plant traits and genetic diversity of maize populations. Based on our results, we concluded that Mengqun 2, Mengqun 4, Zhongzong 7, Mengqun C and Mengqun A could be directly used for the line breeding by selfing for their higher genetic increment of yield and better improvement effects of other agricultural traits. Compared with these 5 populations, the improvement potential of other maize populations was limited for their lower genetic increment. 展开更多
关键词 lmproved s1 selection method Maize population Genetic gain Comparative analysis
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Comparisons of Three Recurrent Selection Methods in the Improvement of Maize Populations 被引量:2
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作者 PENG Ze-bin LI Ming-shun LIU Xin-zhi LI Jun-qiang 《Agricultural Sciences in China》 CAS CSCD 2007年第6期657-664,共8页
The maize population Csyn 4 was improved for three cycles with three recurrent selection methods MS1, MS1-HS, and MHSRRS in northern China. A total of 40 NC Ⅱ testcrosses were made by four testers with Csyn 4 and 10 ... The maize population Csyn 4 was improved for three cycles with three recurrent selection methods MS1, MS1-HS, and MHSRRS in northern China. A total of 40 NC Ⅱ testcrosses were made by four testers with Csyn 4 and 10 improved populations, which were evaluated in four environments in the cropping season of 2005. Analysis of variance indicated a significant progress (P〈 0.05) in yield and other chief agronomic traits in the improved populations and testcrosses, demonstrating that the three recurrent selection methods were effective for increasing grain yield of testcrosses and improvement of general combining ability in maize population. The average grain yield increase of population Csyn 4 in MS1, MS1-HS, and MHSRRS recurrent selections was 266.7 kg ha^-1 (5.3%), 288.0 kg ha^-1 (5.7%), and 231.3 kg ha^-1 (4.6%) per cycle, while the grain yield of S 1 progeny of population for Csyn 4 was increased by 420.0 kg ha^-1 (10.9%), 376.0 kg ha^-1 (9.8%), and 414.7 kg ha^-1 (10.8%) per cycle in MS1, MS1-HS, and MHSRRS recurrent selections, respectively. Linear responses (b) in the MS1, MS1-HS, and MHSRRS recurrent selections were the same as the realized responses of the selection (G) for grain yield increase of Csyn 4 and S1 progeny of the populations. The grain yield of testcrosses increased by 3.3-5.2% on average per cycle. The value of heterosis did not display any differences amongst the different cycles of selections. The GCA for yield component traits of population Csyn 4 was improved significantly by means of three selection methods, whereas the GCA for plant height, ear height, days to silking, and days to pollen did not show significant increase in the recurrent selections. GCA for the number of tassel branches were decreased in the selections, while GCA for the number of plant leaves were increased, but the difference was not significant. 展开更多
关键词 maize (Zea mays L.) population improvement recurrent selection modified s 1 family selection (Ms 1) modified s 1 family-half-sib family combining selection (Ms 1-Hs modified half-sib reciprocal recurrentselection (MHsRRs
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Hu Huanyong:Father of China's Population Geography 被引量:1
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《China Population Today》 1998年第4期21-21,共1页
ProfesorHuHuanyong,oneoftheforefathersinmodernChina’sdemographyandalsothefounderofChina’spopulationgeography... ProfesorHuHuanyong,oneoftheforefathersinmodernChina’sdemographyandalsothefounderofChina’spopulationgeography,diedofilnesonApr... 展开更多
关键词 Huanyong population HU China’s GEOGRAPHY
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A single nucleotide polymorphism in the IL1RL1 gene is associated with Behcet's disease in a Chinese Han population 被引量:1
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作者 Xin-Shu Liu Zi-Yan Wu +7 位作者 Si Chen Chan Zhao Fei Gao Ming-Hang Pei Shan-Shan Jia Yong-Zhe Li Pei-Zeng Yang Mei-Fen Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第9期1315-1320,共6页
AIM:To explore the association of single nucleotide polymorphisms(SNPs)in the IL33/IL1RL1 gene region with the susceptibility to Behcet’s disease(BD)in a Chinese Han population.METHODS:A total of eight SNPs in the ca... AIM:To explore the association of single nucleotide polymorphisms(SNPs)in the IL33/IL1RL1 gene region with the susceptibility to Behcet’s disease(BD)in a Chinese Han population.METHODS:A total of eight SNPs in the candidate gene region(rs11792633,rs7025417,rs10975519 and rs1048274 in IL33;rs2310220,rs12712142,rs13424006 and rs3821204 in IL1RL1)were genotyped in783 BD patients and 701 healthy controls by the Sequenom Mass Array i PLEX platform.RESULTS:A statistically significant association was observed between IL1RL1 rs12712142 and BD patients.The frequency of IL1RL1 rs12712142 variant allele A was significantly lower in BD patients than that in controls(OR=0.8,95%CI:0.69-0.94,Pc=0.039);the genotype distribution(Pc=0.043)and additive and dominant genetic model analyses(OR=0.8,95%CI:0.69-0.94,Pc=0.040 and OR=0.72,95%CI:0.58-0.88,Pc=0.011)also indicated a strong association between rs12712142 and BD patients.CONCLUSION:This is the first study to reveal the association between IL1RL1 rs12712142 variant allele A and the decreased risk of BD in the Chinese Han population,indicating a protective role of IL1RL1 in the pathogenesis of BD. 展开更多
关键词 Behcet’s disease single nucleotide polymorphism Chinese Han population IL33 IL1RL1
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SLC26A4 gene polymorphism and late-onset Alzheimer’s disease in a Han Chinese population from Qingdao,China 被引量:1
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作者 Jifang Zhang Yantuan Li 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第8期754-759,共6页
In a recent genome-wide association study, the SLC26A4 gene rs2072064 polymorphism was found to be associated with late-onset Alzheimer's disease in Caucasians. Here, we investigated this association in a large North... In a recent genome-wide association study, the SLC26A4 gene rs2072064 polymorphism was found to be associated with late-onset Alzheimer's disease in Caucasians. Here, we investigated this association in a large Northern Han Chinese cohort consisting of 599 sporadic late-onset Alzheimer's disease patients and 598 healthy controls matched for sex and age in a Northern Han Chinese population from Qingdao, China. Genotyping by the polymerase chain reaction-ligase detection reaction revealed that there were significant differences in the genotype (P = 0.017) and allele (P = 0.007) frequencies of the rs2072064 polymorphism between late-onset Alzheimer's disease patients and controls. The A allele of this polymorphism was significantly associated with a reduced risk of late-onset Alzheimer's disease (odds ratio (OR) = 0.792, 95% confidence interval (CI) = 0.670-0.937, P = 0.007). When the data were stratified by the apolipoprotein E E4 status, there was a significant difference only among apolipoprotein E E4 non-carriers (genotypic P = 0.001, allelic P = 0.001). Furthermore, the association between rs2072064 and late-onset Alzheimer's disease remained significant by logistic regression analysis after adjustment for age, gender, and the apolipoprotein E E4 carrier status (dominant model: OR = 0.787, 95% CI = 0.619-1.000, P = 0.050; recessive model: OR = 0.655, 95% CI = 0.448-0.959, P= 0.030; additive model: OR = 0.792, 95% CI = 0.661-0.950, P = 0.012). These findings suggest that SLC26A4 is a susceptibility gene for late-onset Alzheimer's disease in a Northern Han Chinese population from the Qingdao area. 展开更多
关键词 neural regeneration neurodegenerative diseases late-onset Alzheimer's disease sLC26A4 rs2072064 POLYMORPHIsM genetic association Han Chinese population apolipoprotein E NEUROREGENERATION
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China’s Tibetan Population and Population in Tibet 被引量:1
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作者 Guo Daping(China Population information and Research Centre) 《China Population Today》 1996年第2期7-8,共2页
China’sTibetanPopulationandPopulationinTibetGuoDaping(ChinaPopulationinformationandResearchCentre)TheTibet(X... China’sTibetanPopulationandPopulationinTibetGuoDaping(ChinaPopulationinformationandResearchCentre)TheTibet(Xizang)AutonomousR... 展开更多
关键词 China s Tibetan population and population in Tibet
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GROWTH, REPRODUCTION & POPULATION STRUCTURE OF THE FRESHWATER CRAB SINOPOTAMON YANG TSEKIENSE BOTT, 1967, FROM ZHEJIANG, CHINA
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作者 陈涛 赖伟 堵南山 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1994年第1期84-90,共7页
Monthly investigatiom were made on the population of Chinese freshwater crab, Sinopotamon yangteskiense Bott, 1967 from April, 1984 to Match, 1985. The data on 4413 specimens show that the growth was affected mainly b... Monthly investigatiom were made on the population of Chinese freshwater crab, Sinopotamon yangteskiense Bott, 1967 from April, 1984 to Match, 1985. The data on 4413 specimens show that the growth was affected mainly by temperature. During the April to November growth period, the crabs’ major development occured from June through October. One year was required for a fine white oocyte to develop into a mature egg. The reproduction period was June-October. Females bearing eggs were taken from June-August, and crabs with young were found from July-October. The females reproduced once a year but could for more than one year. The number of eggs carried by a female varied greatly according to the size of the crab, ranging from 30 to 100 eggs. New-bom crabs become mature after 1-2 yeats. The sex ratio was approximately 1:1 in the overall population. However, the larger crabs are predominantly male. The age distribution of S. yangtsekinese was estimated from size frequency histograms. There were more adult 展开更多
关键词 GROWTH curve vitellogenesis. population s. yangtsekiense sEX ratio
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Fair Plan 8: Earth’s Climate Future—Pope Francis’ Population Mistake 被引量:1
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作者 Michael E. Schlesinger Michael Ring Emily F. Cross 《Atmospheric and Climate Sciences》 2016年第1期103-111,共9页
Pope Francis wrote in his Encyclical Letter Laudato Si’: On Care for Our Common Home: “Instead of resolving the problems of the poor and thinking of how the world can be different, some can only propose a reduction ... Pope Francis wrote in his Encyclical Letter Laudato Si’: On Care for Our Common Home: “Instead of resolving the problems of the poor and thinking of how the world can be different, some can only propose a reduction in the birth rate.” … “To blame population growth instead of extreme and selective consumerism on the part of some is one way of refusing to face the issues.” Here, we test the hypothesis that population size does not matter. We do so in terms of the effect of the size of the human population on its emission of greenhouse gases. We find that the hypothesis is false = PO-PULATION MATTERS. Ceteris paribus, the larger the population of human beings on Planet Earth, the more difficult it will be to reduce, and finally eliminate, the emission of greenhouse gases by humanity and, thereby, constrain human-caused climate change = Anthropogenic Global Warming. 展开更多
关键词 Earth’s Climate Future population Matters
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Sand-dust Storm, Population and Environment in Northwest China
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作者 Liu Shao Guangzhou Research Institute of Environmental Protection, Guangzhou 510620, China 《Chinese Journal of Population,Resources and Environment》 2004年第4期17-24,共8页
Sand-dust storms are the result of the integrated influences of climate, geography, society and human factors. A theoretical framework is built to explain the coherence of population growth, agriculture change and env... Sand-dust storms are the result of the integrated influences of climate, geography, society and human factors. A theoretical framework is built to explain the coherence of population growth, agriculture change and environmental degradation. On the basis of the analysis of the causes of the sand-dust storm in terms of human factors, a discussion will be given to show that these factors are internally consistent with the theoretical framework. After that, it will look at China's Agenda 21 and try to find relevant measures to reduce such large sand-dust storms happening in Northwest China and eventually make this area develop sustainably. 展开更多
关键词 sand-dust storm population ENVIRONMENT china’s Agenda 21 sUsTAINABILITY
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tatistics about China's Population In 1997
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《China Population Today》 1998年第3期14-14,共1页
StatisticsaboutChina’sPopulationIn1997Astatisticalbuletinonthenationaleconomicandsocialdevelopmentin1997was... StatisticsaboutChina’sPopulationIn1997Astatisticalbuletinonthenationaleconomicandsocialdevelopmentin1997wasreleasedbytheStat... 展开更多
关键词 In tatistics population ABOUT China’s
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Population structure of the Atlantic sand fiddler crab Uca pugilator along the eastern coast of US revealed by molecular data
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作者 David A. WEESE Denson K. MCLAIN +1 位作者 Ann E. PRATT Quentin Q. FANG 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第2期150-157,共8页
The Atlantic sand fiddler crab Uca pugilator is an extremely abundant crab found along the eastern coast of the United States. Fiddler crabs have a life cycle with an obligatory planktonic larval phase of 30-90 days,w... The Atlantic sand fiddler crab Uca pugilator is an extremely abundant crab found along the eastern coast of the United States. Fiddler crabs have a life cycle with an obligatory planktonic larval phase of 30-90 days,which might be expected to lead to widespread larval dispersal and consequent genetic homogeneity over considerable distances. However,a large amount of morphological and behavioral variation is found between northern and southern populations along the eastern coast. This study was undertaken to determine the population genetic structure of U.pugilator and to determine whether these differences may have a genetic basis. The population structure of the fiddler crab was analyzed using 472 individuals collected from 12 sites along the eastern coast. PCR-based single stand conformation polymorphism (SSCP) was used to investigate between-site variation in the mitochondrial 16S rRNA gene of these individuals. Analysis of genetic variation indicated frequent gene flow between nearby localities,but much reduced levels between populations separated by larger geographic distances. Thus,despite the potential for high dispersal by planktonic larvae,population differentiation and isolation by distance is evident between northern and southern populations of U.pugilator. A high amount of genetic differentiation (F ST =0.3468) was found between northern and southern regions suggesting that the morphological and behavioral differences between these two regions have a genetic basis and may represent subspecies. 展开更多
关键词 Atlantic sand fiddler crab Uca pugilator Deeapoda Molecular population genetics Gene flow ssCP 16s rDNA
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Physical Conditions of China's Adult Population
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《China Population Today》 1998年第4期20-20,共1页
Physicalmonitoringshowsthephysicalconditionsof71.4%ofChineseadultpopulationhavereachedrequiredstandards,ofwh... Physicalmonitoringshowsthephysicalconditionsof71.4%ofChineseadultpopulationhavereachedrequiredstandards,ofwhichmenare71.2%and... 展开更多
关键词 PHYsICAL population CONDITIONs ADULT China’s
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Enterobius vermicularis infection among population of General Mansilla,Argentina
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作者 Betina C Pezzani Marta C Minvielle +3 位作者 Maria M de Luca María A Córdoba María C Apezteguía Juan A Basualdo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第17期2535-2539,共5页
AIM:To evaluate the relationships between the personal, sociocultural,and environmental characteristics,and the presence or absence of symptoms with the detection of Enterobius vermicularis(E.vermicularis)in a populat... AIM:To evaluate the relationships between the personal, sociocultural,and environmental characteristics,and the presence or absence of symptoms with the detection of Enterobius vermicularis(E.vermicularis)in a population sample in our region(General Mansilla,Province of Buenos Aires,Argentina),by individual and familiar analyses. METHODS:E.verrnicularis was diagnosed in 309 people from 70 family units residing in the urban area and the rural area of the city of General Mansilla.Each of them was surveyed so as to register personal,environmental and sociocultural data.Questions about the presence or absence of anal itch,abdominal pain and sleeping disorder were also asked.Significant associations were determined by square chi tests.Logistic regression models were adjusted by using a backward conditional stepwise method to determine the presence of this parasite in the individuals and in the families. RESULTS:The parasites were found in 29.12%(90/309) of the individuals,with a frequency of 14.28%(20/140) among the heads of the families and of 41.42%(70/169) among the children.The only variables showing a significant association were affiliation,where the risk category was “being the son/daughter of”,and the symptoms were abdominal pain,sleeping disorder,and anal itch.Families with a member infected with parasite were considered Positive Families(PF)and they were 40/70(57.14%),only 5%(2/40)of the PF had 100% of their members infected with the parasite.The logistic regression models applied showed that the risk categories were mainly affiliation(son/daughter) and housing(satisfactory)among others. CONCLUSION:The presence of E.vermiculariswas proved in one third of the studied population.The frequency of families with all their members infected with the parasite was very low.Most of the studied personal,sociocultural, and environmental variables did not turn out to be significantly associated with the presence of the parasite.An association with the category of“son/daughter”and housing classified as“satisfactory”was determined.The latter may be due to the fact that the people living in that category of housing have hygienic practices at home that favour the distribution of the eggs in the environment.The presence of the analysed symptoms was associated with the presence of the parasite, thus strengthening the need of periodical control of the population showing at least one of these symptoms. 展开更多
关键词 Enterobius Abdominal Pain Adult Anal Canal ANIMALs ARGENTINA Child ENTEROBIAsIs Family Health Female Humans Male PRURITUs Research support Non-U.s. Gov't Risk Factors Rural population sANITATION socioeconomic Factors Urban population
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Present Situation and Projection of Tibet's Population
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《China Population Today》 1997年第Z1期28-28,共1页
The following is up-to-date inform at ion about Tibet's Population.In 1995,there was a population about 2.43 million in the region,according to my estima-tion based on data from the 1990 census and annual sam-plin... The following is up-to-date inform at ion about Tibet's Population.In 1995,there was a population about 2.43 million in the region,according to my estima-tion based on data from the 1990 census and annual sam-pling surveys.The birth rate was 28 per thousand,the death rate ten per thousand and the natural increase rate 18 per thousand. 展开更多
关键词 Tibet’s and PROJECTION sITUATION population PREsENT
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China's Impoverished Population Down to 30 Million
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《China Population Today》 2001年第6期15-16,共2页
关键词 THAN China’s Impoverished population Down to 30 Million DOWN
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Can population genomics guide future therapeutic gene transfer strategies for Parkinson’s disease?
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作者 Massimo S. Fiandaca Robert M. Padilla +1 位作者 Ishmeal Conteh Howard J. Federoff 《Open Journal of Genetics》 2013年第2期19-29,共11页
Medical and surgical therapies for patients with Parkinson’s disease (PD) are typically considered and initiated upon development of clinical signs, especially therapeutic gene transfer therapies. Early clinical tria... Medical and surgical therapies for patients with Parkinson’s disease (PD) are typically considered and initiated upon development of clinical signs, especially therapeutic gene transfer therapies. Early clinical trials delivering transgenes within the brains of PD patients have confirmed their safety and suggested mild to moderate efficacy. Confirmatory phase III trials have yet to be undertaken with any of the current treatment regimens. During the development of PD gene therapy, mapping of the human genome was finalized and provides major insights into the normal and pathogenic genetic variabilities of populations. Genome wide association studies (GWAS) have expanded the genetic defects and risk factors accompanying clinical PD. Advanced genomic investigations may allow asymptomatic individuals with a high risk of developing PD, and evident presymptomatic nigrostriatal deficiencies, to consider early treatment approaches. Herein we propose that certain genomically and clinically defined PD patients may provide unique opportunities for testing neuronotrophic gene therapy in a pathobiological environment that is antecedent to overt motoric dysfunction. Such an approach may finally allow testing of the disease-altering capabilities of therapeutic gene transfer in PD. 展开更多
关键词 Biomarkers Functional Imaging Gene Therapy Parkinson’s Disease population GENOMICs PRODROMAL Phase
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