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Structural-Adaptation Features of Assimilation Organs of the Species Salsola incanescens Cam. in Conditions of Kyzylkum
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作者 Guli A. Ibrokhimova Guljan M. Duschanova 《American Journal of Plant Sciences》 CAS 2024年第7期589-602,共14页
The article presents the results of the morpho-anatomical structure of the assimilation organs of the species Salsola leptoclada Gand, which is widespread in the Kyzylkum desert region of Uzbekistan, and reveals the s... The article presents the results of the morpho-anatomical structure of the assimilation organs of the species Salsola leptoclada Gand, which is widespread in the Kyzylkum desert region of Uzbekistan, and reveals the structural, diagnostic and adaptive features. In the assimilation organs, Kranz type of mesophyll was found: in the cotyledons of the Kranz-spherical (Atriplicoid) type, and in the leaf—mesophylls of the Kranz-centric (Salsoloid) and Kranz-ventrodorsal type. These revealed diagnostic features of the assimilating organs of this species in arid conditions noted C4-type photosynthesis. Based on the comparative biometric analysis of quantitative indices of the anatomical features of the assimilating organs, xero-halomorphic features predominate. Halomorphic features are in the cotyledons—thin outer walls of the epidermal cells;few stomata of the anomocytic and paracytic type;few rows of spongy cells (3 - 4 rows);few vascular bundles of the collateral type and xylem, in the leaf—large and thin outer walls of the epidermal cells;succulence of the leaf mesophyll, the presence of aquiferous cells;large palisade, keratin and aquiferous cells. Xeromorphic features in the cotyledons—small and numerous epidermal cells and hemiparacytic type stomata also deep immersion;small palisade cells and a high palisade index, small spongy, hypodermal and keratin cells;small diameter of the xylem in vascular bundles;in the leaf numerous epidermal cells and stomata also deeply immersed;presence and numerous multicellular nodular, dentate trichomes;multi-row water-bearing cells;high palisade index;small and numerous xylem;numerous peripheral vascular bundles of the collateral type. These identified specific diagnostic features showing adaptation to arid conditions can also serve in the identification of plant materials. 展开更多
关键词 Morphology ANATOMY COTYLEDON LEAF Salsola incanescens south-west kyzylkum
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Distribution Pattern and State of Coenotic Population of <i>Tulipa lehmanniana</i>Merckl. in Kyzylkum Desert Conditions (Uzbekistan) 被引量:4
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作者 Ozodbek S. Abduraimov Habibullo F. Shomurodov Azizbek S. Abduraimov 《American Journal of Plant Sciences》 2017年第2期288-296,共9页
The current state of coenotic populations of rare and endangered species of Uzbekistan-Tulipa lehmanniana Merckl. is given. Within the western part of the area (Kyzylkum desert) in different ecological and phytocenoti... The current state of coenotic populations of rare and endangered species of Uzbekistan-Tulipa lehmanniana Merckl. is given. Within the western part of the area (Kyzylkum desert) in different ecological and phytocenotic conditions, 8 coenotic populations of the species were identified. Based on the number of organism and population traits, the current state of coenotic populations of the species was evaluated. It was revealed that the vast majority of coenopopulations are in pessimal state. Coenopopulation only growing on the eastern part of the mountain Kuljuktau was assessed as optimal. 展开更多
关键词 Tulipa lehmanniana LILIACEAE kyzylkum Distribution Coenotic POPULATION
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Fodder Halophytes for Saline Lands of Kyzylkum Desert 被引量:1
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作者 Lola S. Ortiqova 《American Journal of Plant Sciences》 2019年第9期1517-1526,共10页
The article is devoted to the economic and biological characteristics of promising desert semi-shrub halophytes (Kochia prostrate, Salsola orientalis, Ceratoides ewersmaniana, Halothamhus subaphyllus, Camphorosma less... The article is devoted to the economic and biological characteristics of promising desert semi-shrub halophytes (Kochia prostrate, Salsola orientalis, Ceratoides ewersmaniana, Halothamhus subaphyllus, Camphorosma lessingii) to improve saline lands of the Kyzylkum desert. 展开更多
关键词 kyzylkum DESERT PASTURES SALINE Lands Karakul
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Seroepidemiology of hepatitis C and its risk factors in Khuzestan Province, South-West of Iran:A case-control study 被引量:2
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作者 Eskandar Hajiani Jalal Hashemi +3 位作者 Rahim Masjedizadeh Ali Akbar Shayesteh Esmail Idani Tahereh Rajabi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第30期4884-4887,共4页
AIM:To evaluate possible risk factors for the spread of hepatitis C infection and to analyze the characteristics of the epidemiological and clinical patterns among the patients with hepatitis C infection. METHODS: D... AIM:To evaluate possible risk factors for the spread of hepatitis C infection and to analyze the characteristics of the epidemiological and clinical patterns among the patients with hepatitis C infection. METHODS: During a five-year period a cross-sectional study was conducted among HCV positive individuals referred to the Ahwaz JundiShapour University Hospitals (AJSUH) and Hepatitis Clinic from 1 Sept 1999 to 1 Sept 2003. The control group consisted of first time blood donors referred to the Regional Blood Transfusion organization. Enzyme-linked immunosorbent assay and recombinant immunoblot assay anti-hepatitis C virus (HCV) tests were performed for two groups. Positive serum specimens were retested using polymerase chain reaction (PCR) for HCV RNA. Risk factors were evaluated using a questionnaire. Reported risk factors among infected subjects ("HCV-positive") were compared to those of subjects never exposed ("HCV-negative") to HCV. RESULTS: A total of 514 subjects were studied for HCV, of which 254 were HCV-positive and 260 HCV- negative donors comprised the control group. Mean age of the patients was 28.4 (Std 15.22) years. HCV-positive subjects were more likely to be of male gender (63% versus 37%). Transfusion 132 (52%), non-intravenous (n-iv) drug abuse and iv drug abuse 37 (14.5%), haemodialysis 25 (10%), receiving wounds at war and extramarital sexual activities (2.4%), tattooing (3.6%) were found to be independent risk factors of being HCV-positive. No apparent risk factors could be demonstrated in 29 (11.2%) of the positive cases. CONCLUSION: Our data indicate that a history of transfusion and iv drug abuse and haemodialysis are important risk factors for HCV infection in our area and that more careful pretransfusion screening of blood for anti- HCV must be introduced in our blood banks. Improvements in certain lifestyle patterns, and customs in this area may be essential to prevent transmission of the infection. 展开更多
关键词 Epidemiological patterns Hepatitis C virus Risk factors south-west of Iran
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Resolution pattern of jaundice among children presenting with severe malaria in rural South-West Nigeria 被引量:1
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作者 Osonuga OA Osonuga A +1 位作者 Osonuga AA Osonuga IO 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第7期551-553,共3页
Objective:To compare the pattern of jaundice resolution among children with severe malaria treated with quinine and artemether.Methods:Thirty two children who fulfilled the inclusion criteria were recruited for the st... Objective:To compare the pattern of jaundice resolution among children with severe malaria treated with quinine and artemether.Methods:Thirty two children who fulfilled the inclusion criteria were recruited for the study from two hospitals with intensive care facilities.They were divided into two groups:'Q' and 'A',receiving quinine and artemether.respectively.Jaundice was assessed by clinical examination.Results:Sixteen out of 32 children recruited(representing50%) presented with jaundice on the dav of recruitment.The mean age was(7.00±2.56) years.On day 3,tour patients in 'A' and six patients in 'O' had jaundice.By day 7.no child had jaundice.Conclusion:The study has shown that hoth drugs resolve jaundice although artemether relatively resolves it faster by the third day. 展开更多
关键词 JAUNDICE Quinine Artemether Severe malaria south-west NIGERIA
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Evaluation of forest disturbance in south-west Zabaikalia (East Siberia) 被引量:1
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作者 Т.А.MIKHAILOVA L.V.AFANASIEVA +1 位作者 O.V.KALUGINA О.V.SHERGINA 《Forestry Studies in China》 CAS 2013年第4期332-339,共8页
The forest estate in south-west Zabaikalia, a territory included in the Lake Baikal catchment area, has been investigated. For this purpose we have used both data of our own studies and monitoring data of environmenta... The forest estate in south-west Zabaikalia, a territory included in the Lake Baikal catchment area, has been investigated. For this purpose we have used both data of our own studies and monitoring data of environmental protection bodies. It shows that in our study area, fires, fellings, entomo-parasites and air pollution are the major negative factors affecting the state of the forest. In the period from 2003 to 2008 fires were registered in the area of over 500 thousand ha, pest foci in the forests covering an area of over 330 thousand ha, where almost 5 million m3wood was cut in an area of about 43 thousand ha. The total area of forests in our study affected by air pollution amounts to about 700 thousand ha. According to the results, forest pollution in the territory is concentrated in the vicinity of large-scale industrial complexes, for distances up to about 40 km. The total area of forests weakened by air pollution amounts to about 2 million ha. 展开更多
关键词 south-west Zabaikalia Lake Baikal catchment area forest state negative factors
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Structural Features of the Leaf of Ephemeral Species of Representatives of the Brassicaceae Burnett Family in Southwestern Kyzylkum (Uzbekistan)
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作者 Gulbakhor S. Tursinbaeva 《American Journal of Plant Sciences》 2019年第9期1631-1648,共18页
The results of a study conducted by light microscopy of the anatomical structure of the leaf in ephemeral species from the family Brassicaceae growing under the conditions of Kyzylkum (Uzbekistan) are presented. The f... The results of a study conducted by light microscopy of the anatomical structure of the leaf in ephemeral species from the family Brassicaceae growing under the conditions of Kyzylkum (Uzbekistan) are presented. The following diagnostic, structural adaptive features were revealed: a leaf lamellar, dentate (Diptychocarpus strictus), in Leptaleum filifolium—valky. It is pubescent with various types of trichomes: stellate, dendroid (Meniocus linifolius), equilateral (Streptoloma desertorum) and unequal (Strigosella, Leptaleum filifolium species), unicellular hooked (Leptaleum filifolium). Epidermal cells flattened with wavy or winding walls. The stomata are numerous, not submerged, anomocytic, hemiparacytic, anisocytic types are noted. In all species, the isolate-palisade type of leaf mesophyll predominates. Vascular bundles of all species are sclerified. The main protective features of the leaf of species of the family Brassicaceae are pubescence and sclerification of vascular bundles. We consider the mesomorphic and xeromorphic lines of development ancient and independent. Identified and described signs that can be used in taxonomy and ecology. 展开更多
关键词 ANATOMY LEAF EPHEMERAL Brassicaceae kyzylkum Uzbekistan
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The Current Situation of Coenopopulation of <i>Lepidium subcordatum</i>Botsch. et Vved. (<i>Brassicaceae</i>) in Relict Mountains Kyzylkum (Uzbekistan)
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作者 Tashkhanim T. Rakhimova Nodira K. Rakhimova +2 位作者 Khabubullo F. Shomurodov Bekhzod A. Adylov Vasila K. Sharipova 《American Journal of Plant Sciences》 2018年第13期2612-2625,共14页
Lepidium subcordatum Botsch. et Vved. (Brassicaceae) is a rare endemic species of relict mountains of the Kyzylkum desert. The plant is listed in the “Red Data Book of Uzbekistan”. It grows on stony and rocky slopes... Lepidium subcordatum Botsch. et Vved. (Brassicaceae) is a rare endemic species of relict mountains of the Kyzylkum desert. The plant is listed in the “Red Data Book of Uzbekistan”. It grows on stony and rocky slopes of relict mountains. The ontogenetic structure of five coenotypical populations of this taxa growing in the Kuldzhuktau and Auminzatau mountains had been revealed. The ontogenesis duration is more than 20 years in natural habitats. All investigated coenopopulations can be assessed as normal and incomplete. The typical spectrum of coenopopulations is centralized with a peak in the middle-generative individuals. The ontogenetic spectrum of the most studied coenopopulations coincides with the characteristic ontogenetic structure that indicates a favorable environmental condition in region for self-maintenance of L. subcordatum coenopopulations. 展开更多
关键词 ONTOGENESIS ONTOGENETIC Structure Coenopopulations Endemic Species Brassicaceae kyzylkum
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Adaptive Features of Vegetative Organs <i>Juno hippolyti</i>(Vved.) Kamelin and <i>J. narbuti</i>(O. Fedtsch.) Vved. (Juno Tratt.) in the Conditions of the Kyzylkum Desert
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作者 Guljan Madrimbayevna Duschanova Nargiza K. Rahimova +2 位作者 Akida T. Abdullaeva Ergashali Yu Ruzmatov Dildora M. Yusupova 《American Journal of Plant Sciences》 2018年第9期1952-1962,共11页
For the first time, the anatomical structure of the vegetative organs of the species J. hippolyti and J. narbuti was studied in the conditions of Kyzylkum (Uzbekistan, Province Bukhara) and revealed the diagnostic fea... For the first time, the anatomical structure of the vegetative organs of the species J. hippolyti and J. narbuti was studied in the conditions of Kyzylkum (Uzbekistan, Province Bukhara) and revealed the diagnostic features of these species. A different combination of xeromorphic and mesomorphic features was determined, which ensures adaptation to habitat conditions. In J. narbuti xeromorphic features predominate, which indicates a more adaptable and wide distribution in the natural habitat of this species. In J. hippolyti—mesomorphic signs that show the rarity of the species in their natural habitat, compared to J. narbuti. 展开更多
关键词 Anatomy VEGETATIVE ORGANS J. hippolyti J. narbuti kyzylkum
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Structural Features of the Vegetative Organs of <i>Allium kysylkumi</i>Kamelin. Growing in the Conditions of Kyzylkum
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作者 Dildora M. Yusupova Muhabbat H. Ravshanova 《American Journal of Plant Sciences》 2020年第9期1443-1452,共10页
The article presents the results of studies of the anatomical structure of the vegetative organs of </span><i><span style="font-family:Verdana;">Allium </span><span style="fon... The article presents the results of studies of the anatomical structure of the vegetative organs of </span><i><span style="font-family:Verdana;">Allium </span><span style="font-family:Verdana;">kysylkumi</span></i><span style="font-family:Verdana;"> of the Amaryllidaceae family, which grows in the conditions of Kyzylkum (Kokchatau outlier mountain). The characteristic diagnostic features have been determined: the outer membrane of epidermal cells is well developed by the outer folded cuticle, cutinized and more thickened;leaves are amphistomatic;stomata are the most submerged, </span><span style="font-family:Verdana;">anomocytic</span><span style="font-family:Verdana;"> type;isolateral-palisade type of leaf mesophyll;the conducting bundles </span><span style="font-family:Verdana;">are closed, collateral and are arranged in two rows, of which the upper side is represented only by small bundles, in the lower row, 3 large bundles alternate with one small bundle;peduncle and peduncle, parenchymal-beam type of structure;the epidermis is single-row, fold</span><span style="font-family:Verdana;">ed cuticle with more thickened and cutinized;the crustal parenchyma is thin-walled, round-oval, chlorophyll-bearing;the presence of lactic acid is in the cow parenchyma;the primary cortex is separated from the central cylinder by a ring of sclerenchyma;the central cylinder is extensive;closed collateral-type conductive bundles.</span><b> </b><span style="font-family:Verdana;">In the vegetative organs of </span><i><span style="font-family:Verdana;">Allium </span><span style="font-family:Verdana;">kysylkumi</span></i><span style="font-family:Verdana;">, especially in the leaf, xeromorphic characters are pronounced, which indicates the fitness of this species in natural habitat. The revealed structural diagnostic signs of vegetative organs are </span><span style="font-family:Verdana;">species-specific,</span><span style="font-family:Verdana;"> and show the adaptation of this species to its natural habitat, these micromorphological signs are taxonomic significance for distinguishing and identifying </span><i><span style="font-family:Verdana;">Allium</span></i><span style="font-family:Verdana;"> species. 展开更多
关键词 ANATOMY Leaf Stem PEDUNCLE Allium kysylkumi Navoi Region (kyzylkum) Uzbekistan
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Assessment of the State of <i>Onobrychis tavernierfolia</i>Stocks ex Boiss.(Fabaceae) Cenopopulations Southwestern Kyzylkum(Uzbekistan)
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作者 Habibullo F. Shomurodov Ozodbek S. Abduraimov +1 位作者 Rizamat Sh. Khayitov Shakhnoza U. Saribaeva 《American Journal of Plant Sciences》 2021年第7期1043-1050,共8页
In the period 2019-2021, two coenotic populations of </span><i><span style="font-family:Verdana;">O. tavernierfolia</span></i><span style="font-family:Verdana;">... In the period 2019-2021, two coenotic populations of </span><i><span style="font-family:Verdana;">O. tavernierfolia</span></i><span style="font-family:Verdana;"> were studied in different ecological and phytocenotic conditions of relic mountain Kuldzhuktau. Very rare species of the Kyzylkum. It is spread at the Kyzylkum: the Kuldzhuktau, near Ayak-Guzhumdy and Churuk (Bukhara region). Inhabits stony and gypseous slopes. There are three small populations can be found. Limiting factors: degradation of habitat as a result of overgrazing. Measures of protection: not protected.</span></span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">The article is devoted to the assessment of the current state of coenotic populations of the rarest southwestern Kyzylkum (Kuldzhuktau) </span><i><span style="font-family:Verdana;">Onobrychis tavernierfolia</span></i><span style="font-family:Verdana;">. It was found that the studied coenopopulations of </span><i><span style="font-family:Verdana;">O. tavernierfolia</span></i><span style="font-family:Verdana;"> are normal and complete. 展开更多
关键词 Onobrychis Tavernierfolia CENOPOPULATION kyzylkum ASSESSMENT Rare Plant Population Signs
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Prevalence of hepatitis B virus infection and associated risk factors among adult females infected with Human Immunodeficiency Virus in Ogun State,Nigeria
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作者 John Cletus Ihongbe Seyi Samson Enitan +5 位作者 Michael Olugbamila Dada Oluchi Ofem Oluchi Gladys Ofem Effiong Joseph Effiong Olalekan Ademola Kemiki Amarachi Favour Ogbonna 《Infectious Diseases Research》 2023年第3期1-9,共9页
Background:Hepatitis B virus(HBV)infection is prevalent in sub-Saharan Africa,including Nigeria,and is frequently observed in individuals co-infected with human immunodeficiency virus(HIV).Objective:This study aims to... Background:Hepatitis B virus(HBV)infection is prevalent in sub-Saharan Africa,including Nigeria,and is frequently observed in individuals co-infected with human immunodeficiency virus(HIV).Objective:This study aims to evaluate the prevalence of serological markers for hepatitis B virus and identify the associated risk factors among women with HIV undergoing highly active antiretroviral therapy(HAART)in Ogun State,Nigeria.Methods:Ethical approval was obtained from the Babcock University Health Research Ethics Committee(BUHREC)to recruit a total of 110 adult women infected with HIV,receiving treatment at the HIV clinics of Babcock University Teaching Hospital(BUTH)in Ilishan-Remo and General Hospital in Ijebu-Ode,both located in Ogun State,Nigeria.The participants’HIV status were confirmed using three rapid diagnostic kits:Determine(Abbott Laboratories,Tokyo,Japan),Unigold HIV(Trinity Biotech Plc Bray,Co.Wicklow,Ireland),and 1/2 Stat Pak(Abbott Laboratories,Tokyo,Japan)(Chembio Diagnostic Systems,New York,USA).Additionally,an HBV 5 in 1 Panel manufactured by Innovation Biotechnology Co.,Ltd in Beijing,China,was employed to detect HBV markers qualitatively in serum samples.Results:Out of the 110 subjects that voluntarily participated in the study,4(3.6%)tested positive for HBsAg,2(1.8%)tested positive for HBsAb,81(73.6%)tested positive for HBeAg,3(2.7%)tested positive for HBeAb,and 65(59.1%)tested positive for HBcAb.There was no significant correlation between the occurrence of HBsAg and the socio-demographic characteristics of the participants(P>0.05).Various risk factors were identified,including lack of knowledge about HBV,absence of HBV vaccination history,history of blood transfusion,organ transplant,and engaging in unprotected sex,among others.Conclusion:The findings highlight the presence of HBV infection among HIV-positive women undergoing HAART in Ogun State,Nigeria,particularly within the age groups of 18–25 years and 26–30 years.These results emphasize the necessity for continuous and targeted public health interventions among this specific population. 展开更多
关键词 hepatitis B virus serological markers HIV HAART adult females south-west Nigeria
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Rare and Endemic Plants of the Relic Mountain of Sultan-Uvays 被引量:1
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作者 Rabiga X. Yesemuratova 《American Journal of Plant Sciences》 2021年第1期1-6,共6页
The article studied rare and endemic plants scattered on the relic mountain of Sultan-Uvays.<b> </b><span style="font-family:Verdana;">During the studies, the floristic list of the territor... The article studied rare and endemic plants scattered on the relic mountain of Sultan-Uvays.<b> </b><span style="font-family:Verdana;">During the studies, the floristic list of the territory was also formed.</span><b> </b><span style="font-family:Verdana;">Floristical studies revealed 497 species of vascular plants, belonging to 230 genera and 49 families. Investigated flora can be characterized by 1 endemic and 10 subendemic species should be included in the List of rare and endangered plants of Karakalpakistan as well as in the Red Data Book of Uzbekistan. It was found out that the populations of the studied species are in normal condition. Information obtained on the distribution of rare and endemic species is used in the preparation of plans for protection measures and monitoring studies, as well as in the preparation of the next editions of the flora of Uzbekistan and the red book of the Republic of Uzbekistan.</span> 展开更多
关键词 RARE ENDEMIC FLORA Sultan-Uvays kyzylkum
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Hepatitis C virus transmission and its risk factors within families of patients infected with hepatitis C virus in southern Iran:Khuzestan 被引量:2
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作者 Eskandar Hajiani Rahim Masjedizadeh +2 位作者 Jalal Hashemi Mehrdad Azmi Tahereh Rajabi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第43期7025-7028,共4页
AIM: To determine whether hepatitis C virus (HCV) infection of index cases increases intrafamilial transmission (sexual and nonsexual contacts) of HCV. METHODS: In a case-control descriptive study we enrolled 300-hous... AIM: To determine whether hepatitis C virus (HCV) infection of index cases increases intrafamilial transmission (sexual and nonsexual contacts) of HCV. METHODS: In a case-control descriptive study we enrolled 300-household contacts of 60 index cases (40 males and 20 females) of HCV infection and 360 pair- matched controls in Ahwaz JundiShapour University Hospitals from August 1, 1998 to September 1, 2003. The control group consisted of first time blood donors referred to the Regional Blood Transfusion Organization. Serum samples and demographic data and a medical history including the existence of risk factors for HCV (after a questionnaire on the risk factors for parenteral exposure) were obtained from each subject. Antibodies to HCV were detected employing a commercially available second-generation enzyme immunoassay (EIA, Abbott Ⅱ). Positive serum specimens were retested using a second-generation recombinant immunoblot assay (RIBA-2) and a polymerase chain reaction for HCV RNA. Data analysis was carried out for intra-household clustering. RESULTS: Only 4 of 300 (1.33%) cases of household contacts without percutaneous risk factors were positive for HCV Ab while the remaining 296 family contacts were negative for anti-HCV. The mean age of the index cases was 28.4 (Std 15.22) years. The anti-HCV prevalences in parents, spouses, children of the index cases were 0.87% (1/115), 3.39% (2/59)) and 0.79% (1/126), respectively. Among couple partners negative for anti-HCV antibodies, the mean duration of the sexual relationship was 6 years.The two-couple partners positive for anti-HCV antibodies married the index cases for longer than 15 years. The prevalence of positive HCV Ab among household contacts (1.33%) was not significantly higher than that in the controls (1%) (P > 0.06). CONCLUSION: Intrafamilial transmission of HCV is not the significant transmission route and sexual transmission does not seem to play a role in the intrafamilial spread of HCV infection. Intrafamilial transmission of HCV is possible but occurs at a low rate. 展开更多
关键词 Intrafamilial transmission Hepatitis C virus Khuzestan south-west of Iran
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Petrography and Geochemical Characterization of Dolerites from Figuil (Northern Cameroon) and Léré(Southwestern Chad) 被引量:2
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作者 Moussa Ngarena Klamadji Merlin Gountié Dedzo +1 位作者 Rigobert Tchameni Daouda Dawaï 《International Journal of Geosciences》 2020年第7期459-482,共24页
This work presents the petrographic and geochemical data of the dolerite <span>dykes crosscutting the Pan-African basement of Figuil (North-Cameroon) and </span>Léré (South-West Chad) in order to... This work presents the petrographic and geochemical data of the dolerite <span>dykes crosscutting the Pan-African basement of Figuil (North-Cameroon) and </span>Léré (South-West Chad) in order to approach their petrogenesis and their emplacement context. Two groups of dolerites have been highlighted by petrograph<span>ic and geochemical studies. These groups were discrimin</span>ated by their TiO<sub>2</sub>, Fe<sub>2</sub>O<sub>3</sub>, REE, Ba, Nb, Zr, La and Hf contents which are relatively higher in group I;group II, on the other hand, has higher MgO, Mg#, Sc, Ni and Cr contents. The mineralogical assemblage of these dolerites is made up by plagioclases, pyroxenes, olivine, oxides, amphibole, biotite and sometimes pyrite, calcite, apatite, epidote and chlorite. The behaviour of the major and trace elements suggest that studied dolerites have an evolution dominated by fractional crystallization. Most dolerite samples show higher REE concentrations and (La/Yb)<sub>N</sub> > 8.7, (Tb/Yb)<sub>N</sub> > 1.9 and Dy/Yb > 2 ratios characterizing a garnet-bearing mantle. The difference in incompatible elements between the two groups is explained by the degree of partial melting of the same source which becomes more important over time. Low (Ce/Yb)<sub>N</sub> values (3.3 - 11.58) <span>also suggest relatively low partial melting degree of the source. Fractional crystalli</span>zation process was possibly combined with minor crustal contamination as shown by enrichment of Th/Yb from group II to Group I that might be due to turbulent magma emplacement. The chemical compositions of these dolerites are similar to that of continental tholeiites with slightly moderate nega<span>tive Nb-Ta anomalies which are attributed to crustal contamination of magma</span>s. As other dolerites of Cameroon, continental tholeiitic signature of the studied dolerites is evidenced in geotectonic discrimination diagrams with Group II dolerite compositions falling within the field of tholeiitic basalts and group I within the field of alkali basalts. 展开更多
关键词 Doleritic Dykes Pan-African Basement Continental Tholeiites North-Cameroon south-west of Chad
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中央克兹勒库姆区域构造演化及铀成矿特征 被引量:9
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作者 姚振凯 向伟东 +2 位作者 张子敏 杨志 刘茂福 《世界核地质科学》 CAS 2011年第2期84-88,119,共6页
中亚天山造山带中央克兹勒库姆铀成矿区是世界驰名的铀矿产地,区域构造上属叠加于海西期地槽褶皱造山带上的喜马拉雅期活化造山带中的次级造山带,有大量层间氧化带砂岩型和碳硅质板岩型铀矿床分布。经活化构造成矿分析,铀成矿作用经历... 中亚天山造山带中央克兹勒库姆铀成矿区是世界驰名的铀矿产地,区域构造上属叠加于海西期地槽褶皱造山带上的喜马拉雅期活化造山带中的次级造山带,有大量层间氧化带砂岩型和碳硅质板岩型铀矿床分布。经活化构造成矿分析,铀成矿作用经历了多个大地构造演化阶段,地槽造山阶段形成铀源层、体,地台阶段形成部分有利铀成矿和储矿的砂岩层,活化造山阶段形成淋积和热流体成因的工业铀矿床。 展开更多
关键词 中央克兹勒库姆 区域构造演化 铀成矿特征
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Morphology and Structure of Fruits of Some Desert Efemers of the Genus Alyssum L.
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作者 Gulbakhor Sultanovna Tursinbaeva 《American Journal of Plant Sciences》 2017年第13期3443-3449,共7页
The structure of the fetus, seed, embryo of 3 species of ephemerals of the genus Alyssum, collected in the southwestern Kyzylkum, is described. Fetus of the Alyssum species is rounded, wide-pated silicle, with fetus s... The structure of the fetus, seed, embryo of 3 species of ephemerals of the genus Alyssum, collected in the southwestern Kyzylkum, is described. Fetus of the Alyssum species is rounded, wide-pated silicle, with fetus stems of a truncated-conical (A. dasycarpum) shape. Pericarp is 4 - 5 layered. The fetus is seedless (2 - 4), and the seeds are protein-free, with a large embryo. At the general plan of a structure, species have diagnostic signs distinguishing them on the form of a fetus, weight of seeds, the structure of embryo mesophyll. 展开更多
关键词 ANATOMY FETUS Seeds EMBRYO ALYSSUM species kyzylkum
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Distribution of soils and solifluction layers in landslide area of South-West Germany
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作者 Birgit TERHORST 《Chinese Science Bulletin》 SCIE EI CAS 1999年第S1期173-180,共8页
As part of the MABIS research project (Mass movements in South and West-Germany)which was supported by the German Research Foundation (DFG) detailed causal, age and riskanalyses were carried out on several landslides.... As part of the MABIS research project (Mass movements in South and West-Germany)which was supported by the German Research Foundation (DFG) detailed causal, age and riskanalyses were carried out on several landslides. Investigations were carried out on the SwabianJurassic escarpment (South-West Germany). The mass movements were examined by means ofgeomorphological and pedological field mapping, through the differentiation of the solifluctionlayers and through mineralogical analyses. These investigations aimed at distinguishing betweenHolocene and Pleistocene landslides, classifying different climatic cycles of slope evolution andgathering information about potential risk areas. It could be confirmed that large rotationallandslides (earth-slump flows according to Vames 1978) occurred during the Pleistocene period,whereas during the Holocene period these fossil mass movements were only reworked anddisplaced. 展开更多
关键词 LANDSLIDE soil south-west GERMANY heavey mineral slope evolution
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An investigation into the feasibility of a hybrid generator-photovoltaic-wind farm with variable load profile:case of headland south-west of Morocco
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作者 Abdelkader Beyoud Ahmed Bouhaouss 《Clean Energy》 EI 2022年第3期484-495,共12页
A hybrid system proposed by three different specifications for the equipment of a tourist lodge in the headland of south-west Morocco was sized by analysing the limits of load profile constraints,such as hour-to-hour ... A hybrid system proposed by three different specifications for the equipment of a tourist lodge in the headland of south-west Morocco was sized by analysing the limits of load profile constraints,such as hour-to-hour variability(HHR),day-to-day variability(DDR)and the operating reserve rate(ROR).Based on the three-factor Doehlert matrix recommendations,the simulations employed an energy-sizing tool for hybrid renewable-energy systems.Testing was conducted with DDR at 5-30%,HHR at 10-30%and ROR at 0-20%.Under these conditions,a second-order polynomial relationship with a correlation rate of~90%was found between the net present cost(NPC)of the system,the levelized cost of electricity and the various constraint factors.The first specification,SPC(1),composed of generators and batteries,was introduced to control and validate the simulation independently of renewable energy,which showed a positive manifestation with the imposed constraints.The analysis expanded by introducing solar and wind energy resources.The SPC(2)configuration added PV modules to the SPC(1)and the SPC(3)configuration added wind turbines to SPC(2).The effect of DDR,HHR and ROR in the trials was significant by linear regression.At the same time,only DDR had a significant quadratic regression.The others,with their pairwise interactions,were insignificant.The desirability procedure made it possible to calculate the maximum limits of load profile constraint variables leading to targets of LCOE=0.41 US$/kWh and NPC=US$320080.1 of the load profile constraints:the DDR=15.47%and the HHR=26.55%at an ROR rate of 17.77%. 展开更多
关键词 hybrid system wind and photovoltaic energies HOMER software variability in load profile rate of non-load coverage model headland south-west Morocco
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西南少数民族咂酒及其开发前景 被引量:5
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作者 吴勇 詹大方 《贵州民族研究》 CSSCI 北大核心 1995年第1期134-140,共7页
Za wine is a kind. of health drink existing. in the South-West-ern minorities. The author in this article believes that the history of Za wine should be tracked back to at least 7000 years ago The author analyses the ... Za wine is a kind. of health drink existing. in the South-West-ern minorities. The author in this article believes that the history of Za wine should be tracked back to at least 7000 years ago The author analyses the unique feature of Za wine from its raw materi-als, procedures in production to its nutritious compositions, and points out that to develop Za wine has a bright fu ture. 展开更多
关键词 south-west of China MINORITY nationalities Za WINE
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