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  1 / 1902 MEDLINE  
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PMID:29351314
Autor:Zhuang H; Yago M; Settele J; Li X; Ueshima R; Grishin NV; Wang M
Endereço:Department of Entomology, College of Agriculture, South China Agricultural University, Guangzhou, Guangdong, China.
Título:Species richness of Eurasian Zephyrus hairstreaks (Lepidoptera: Lycaenidae: Theclini) with implications on historical biogeography: An NDM/VNDM approach.
Fonte:PLoS One; 13(1):e0191049, 2018.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:AIM: A database based on distributional records of Eurasian Zephyrus hairstreaks (Lepidoptera: Lycaenidae: Theclini) was compiled to analyse their areas of endemism (AoEs), species richness and distribution patterns, to explore their locations of past glacial refugia and dispersal routes. METHODS: Over 2000 Zephyrus hairstreaks occurrences are analysed using the NDM/VNDM algorithm, for the recognition of AoEs. Species richness was calculated by using the option 'Number of different classes' to count the different classes of a variable presented in each 3.0°×3.0° grid cell, and GIS software was used to visualize distribution patterns of endemic species. RESULTS: Centres of species richness of Zephyrus hairstreaks are situated in the eastern Qinghai-Tibet Plateau (EQTP), Hengduan Mountain Region (HDMR) and the Qinling Mountain Region (QLMR). Latitudinal gradients in species richness show normal distribution with the peak between 25° N and 35° N in the temperate zone, gradually decreasing towards the poles. Moreover, most parts of central and southern China, especially the area of QLMR-EQTP-HDMR, were identified as AoEs that may have played a significant role as refugia during Quaternary global cooling. There are four major distributional patterns of Zephyrus hairstreaks in Eurasia: Sino-Japanese, Sino-Himalayan, high-mountain and a combined distribution covering all three patterns. CONCLUSIONS: Zephyrus hairstreaks probably originated at least 23-24 Myr ago in E. Asia between 25° N to 35° N in the temperate zone. Cenozoic orogenies caused rapid speciation of this tribe and extrusion of the Indochina block resulted in vicariance between the Sino-Japanese and the Sino-Himalayan patterns. The four distribution patterns provided two possible dispersal directions: Sino-Japanese dispersal and Sino-Himalayan dispersal.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T


  2 / 1902 MEDLINE  
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PMID:29309420
Autor:Cai J; Li P; Luo X; Chang T; Li J; Zhao Y; Xu Y
Endereço:Provincial Key Laboratory of Biotechnology of Shaanxi Province, Xi'an, China.
Título:Selection of appropriate reference genes for the detection of rhythmic gene expression via quantitative real-time PCR in Tibetan hulless barley.
Fonte:PLoS One; 13(1):e0190559, 2018.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:Hulless barley (Hordeum vulgare L. var. nudum. hook. f.) has been cultivated as a major crop in the Qinghai-Tibet plateau of China for thousands of years. Compared to other cereal crops, the Tibetan hulless barley has developed stronger endogenous resistances to survive in the severe environment of its habitat. To understand the unique resistant mechanisms of this plant, detailed genetic studies need to be performed. The quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) is the most commonly used method in detecting gene expression. However, the selection of stable reference genes under limited experimental conditions was considered to be an essential step for obtaining accurate results in qRT-PCR. In this study, 10 candidate reference genes-ACT (Actin), E2 (Ubiquitin conjugating enzyme 2), TUBα (Alpha-tubulin), TUBß6 (Beta-tubulin 6), GAPDH (Glyceraldehyde 3-phosphate dehydrogenase), EF-1α (Elongation factor 1-alpha), SAMDC (S-adenosylmethionine decarboxylase), PKABA1 (Gene for protein kinase HvPKABA1), PGK (Phosphoglycerate kinase), and HSP90 (Heat shock protein 90)-were selected from the NCBI gene database of barley. Following qRT-PCR amplifications of all candidate reference genes in Tibetan hulless barley seedlings under various stressed conditions, the stabilities of these candidates were analyzed by three individual software packages including geNorm, NormFinder, and BestKeeper. The results demonstrated that TUBß6, E2, TUBα, and HSP90 were generally the most suitable sets under all tested conditions; similarly, TUBα and HSP90 showed peak stability under salt stress, TUBα and EF-1α were the most suitable reference genes under cold stress, and ACT and E2 were the most stable under drought stress. Finally, a known circadian gene CCA1 was used to verify the service ability of chosen reference genes. The results confirmed that all recommended reference genes by the three software were suitable for gene expression analysis under tested stress conditions by the qRT-PCR method.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T


  3 / 1902 MEDLINE  
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PMID:29224130
Autor:Wang M; Wang Y; Baloch AR; Pan Y; Xu F; Tian L; Zeng Q
Endereço:College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China.
Título:Molecular epidemiology and characterization of bovine leukemia virus in domestic yaks (Bos grunniens) on the Qinghai-Tibet Plateau, China.
Fonte:Arch Virol; 163(3):659-670, 2018 Mar.
ISSN:1432-8798
País de publicação:Austria
Idioma:eng
Resumo:Bovine leukemia virus (BLV) is a member of the genus Deltaretrovirus of the family Retroviridae and cause a chronic lymphosarcoma, which is extensive in cattle. In yaks (Bos grunniens), the distribution, strains and genetic characteristics of BLV have rarely been studied. The aim of our study was to investigate BLV infections in domestic yaks and determine the genetic variability of BLV circulating in a region of the Qinghai Tibet Plateau, China. Blood samples were collected from 798 yaks, which were from different farms from Gansu, Qinghai and Sichuan provinces surrounding the Qinghai-Tibet Plateau. Nested PCR targeting BLV long terminal repeats was used to detect the BLV provirus. The highest prevalence of BLV infection was in Gansu province, where it was 18.93% (39/206) in white yaks from Tianzhu City and 19.14% (31/162) in black yaks from Gannan City. In Qinghai and Sichuan provinces, the prevalence of BLV in black yaks was 14.83% (35/236) and 14.94% (29/194), respectively. The prevalence of BLV was not significantly different in yaks up to one year old than in older animals. Phylogenetic analysis was performed using 16 different env-gp51 (497-bp) gene sequences from the three provinces and 71 known BLV strains, which revealed that in both Gansu and Qinghai provinces, genotypes 6 and 10 of the BLV strains were at high levels, whereas only genotype 10 was prevalent in Sichuan Province. Phylogenetic analysis and sequence comparisons revealed 95.7-99.8% sequence identity among the full-length env genes of 16 strains, nearly full-length genome sequences of six BLV strains, and those of the known genotypes 6 and 10 of BLV. This study provides comprehensive information is regarding the widespread infection of domestic yaks with BLV on the Qinghai-Tibet Plateau of China, and shows that at least two BLV genotypes (genotypes 6 and 10) are circulating in this population.
Tipo de publicação: JOURNAL ARTICLE


  4 / 1902 MEDLINE  
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PMID:29406111
Autor:Duo B; Cui L; Wang Z; Li R; Zhang L; Fu H; Chen J; Zhang H; Qiong A
Endereço:Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China; Department of Chemistry & Environmental Science, Tibet University, Lhasa 850000, China.
Título:Observations of atmospheric pollutants at Lhasa during 2014-2015: Pollution status and the influence of meteorological factors.
Fonte:J Environ Sci (China); 63:28-42, 2018 Jan.
ISSN:1001-0742
País de publicação:Netherlands
Idioma:eng
Resumo:Atmospheric pollutants including SO , NO , CO, O and inhalable particulate matter (PM and PM ) were monitored continuously from March 2014 to February 2015 to investigate characteristics of air pollution at Lhasa, Tibetan Plateau. Species exhibited similar seasonal variations except O , with the peaks in winter but low valleys in summer. The maximum O concentration was observed in spring, followed by summer, autumn, and winter. The positive correlation between O and PM in spring indicated similar sources of them, and was assumed to be turbulent transport. Temperature was the dominant meteorological factor for most species in spring. High temperature accelerates O photochemistry, and favors air disturbance which is conductive to dust resuspension in spring. Relative humidity (RH) and atmospheric pressure were the main meteorological factors in summer. RH showed negative correlations with species, while atmospheric pressure posed opposite situation. Wind speed (WS) was the dominant meteorological factor in autumn, the negative correlations between WS and species indicated diffusion by wind. Most species showed non-significant correlations with meteorological factors in winter, indicating the dependence of pollution on source emission rather than restriction by meteorology. Pollution weather character indicated that emissions were from biomass burning and dust suspension, and meteorological factors also played an important role. Air stream injection from the stratosphere was observed during O pollution period. Air parcels from Southwest Asia were observed during air pollution period in winter. An enhancement in air pollutants such as O would be expected in the future, more attention should be given to countermeasures for prevention of air pollution in the future.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Air Pollutants); 0 (Dust)


  5 / 1902 MEDLINE  
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PMID:29381998
Autor:Wang L; Ren G; Li J; Zhu L; Niu F; Yan M; Li J; Yuan D; Jin T
Endereço:Key Laboratory of Molecular Mechanism and Intervention Research for Plateau Diseases of Tibet Autonomous Region, School of Medicine, Xizang Minzu University, Xianyang, Shaanxi.
Título:Genetic polymorphism analysis of cytochrome P4502E1 (CYP2E1) in a Chinese Tibetan population.
Fonte:Medicine (Baltimore); 96(47):e8855, 2017 Nov.
ISSN:1536-5964
País de publicação:United States
Idioma:eng
Resumo:Cytochrome P4502E1 (CYP2E1) gene genetic polymorphisms vary markedly in frequency among different ethnic and racial groups.We studied the genotype distributions and allele frequencies of 3 CYP2E1 polymorphisms: CYP2E11A, CYP2E17A, and CYP2E17C by polymerase chain reaction technique in a sample of 100 healthy subjects representing Tibetan population.The frequencies of CYP2E11A, 7A, and 7C alleles were 0.705, 0.125, and 0.170, respectively. Compared with other populations, we found that the allele frequencies of the variants -352A>G (rs2070672) and -333A>T (rs2070673) in this Tibetan population have significant differences compared with European-American, African-American, Japanese, Korean, and other different geographic areas in Chinese Han population. Furthermore, the results of protein prediction revealed that the variant 6397G>A (rs61710826) could influence the protein structure and function.These findings in this study would be valuable for pharmacogenetics for drug therapy and drug discovery. However, further studies in larger samples are warranted to confirm our results.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:EC 1.14.13.- (Cytochrome P-450 CYP2E1)


  6 / 1902 MEDLINE  
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PMID:28461206
Autor:Chen L
Endereço:College of Bioengineering, Henan University of Technology, Zhengzhou 450001, PR China; Collaborative Innovation Center of Grain Storage Security in Henan Province, Zhengzhou 450001, PR China. Electronic address: chen_liang.cl@163.com.
Título:Complete genome sequence of Bacillus velezensis LM2303, a biocontrol strain isolated from the dung of wild yak inhabited Qinghai-Tibet plateau.
Fonte:J Biotechnol; 251:124-127, 2017 Jun 10.
ISSN:1873-4863
País de publicação:Netherlands
Idioma:eng
Resumo:Bacillus velezensis LM2303 is a biocontrol strain with a broad inhibitory spectrum against plant pathogens, isolated from the dung of wild yak inhabited Qinghai-Tibet plateau, China. Here we present its complete genome sequence, which consists of a single, circular chromosome of 3,989,393bp with a 46.68% G+C content. Genome analysis revealed genes encoding specialized functions for the biosynthesis of antifungal metabolites and antibacterial metabolites, the promotion of plant growth, the alleviation of oxidative stress and nutrient utilization. And the biosynthesis of antimicrobial metabolites in strain LM2303 was confirmed by biochemical analysis, while its plant growth promoting traits were confirmed by inoculation tests. Our results will establish a better foundation for further studies and biocontrol application of B. velezensis LM2303.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Biological Control Agents)


  7 / 1902 MEDLINE  
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PMID:28448508
Autor:Jeong C; Peter BM; Basnyat B; Neupane M; Beall CM; Childs G; Craig SR; Novembre J; Di Rienzo A
Endereço:Department of Human Genetics, University of Chicago, Chicago, IL, United States of America.
Título:A longitudinal cline characterizes the genetic structure of human populations in the Tibetan plateau.
Fonte:PLoS One; 12(4):e0175885, 2017.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:Indigenous populations of the Tibetan plateau have attracted much attention for their good performance at extreme high altitude. Most genetic studies of Tibetan adaptations have used genetic variation data at the genome scale, while genetic inferences about their demography and population structure are largely based on uniparental markers. To provide genome-wide information on population structure, we analyzed new and published data of 338 individuals from indigenous populations across the plateau in conjunction with worldwide genetic variation data. We found a clear signal of genetic stratification across the east-west axis within Tibetan samples. Samples from more eastern locations tend to have higher genetic affinity with lowland East Asians, which can be explained by more gene flow from lowland East Asia onto the plateau. Our findings corroborate a previous report of admixture signals in Tibetans, which were based on a subset of the samples analyzed here, but add evidence for isolation by distance in a broader geospatial context.
Tipo de publicação: JOURNAL ARTICLE


  8 / 1902 MEDLINE  
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PMID:29236754
Autor:Chang Y; Wang J; Qin D; Ding Y; Zhao Q; Liu F; Zhang S
Endereço:State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China.
Título:Methodological comparison of alpine meadow evapotranspiration on the Tibetan Plateau, China.
Fonte:PLoS One; 12(12):e0189059, 2017.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:Estimation of evapotranspiration (ET) for alpine meadow areas in the Tibetan Plateau (TP) is essential for water resource management. However, observation data has been limited due to the extreme climates and complex terrain of this region. To address these issues, four representative methods, Penman-Monteith (PM), Priestley-Taylor (PT), Hargreaves-Samani (HS), and Mahringer (MG) methods, were adopted to estimate ET, which were then compared with ET measured using Eddy Covariance (EC) for five alpine meadow sites during the growing seasons from 2010 to 2014. And each site was measured for one growing season during this period. The results demonstrate that the PT method outperformed at all sites with a coefficient of determination (R2) ranging from 0.76 to 0.94 and root mean square error (RMSE) ranging from 0.41 to 0.62 mm d-1. The PM method showed better performance than HS and MG methods, and the HS method produced relatively acceptable results with higher R2 (0.46) and lower RMSE (0.89 mm d-1) compared to MG method with R2 of 0.16 and RMSE of 1.62 mm d-1, while MG underestimated ET at all alpine meadow sites. Therefore, the PT method, being the simpler approach and less data dependent, is recommended to estimate ET for alpine meadow areas in the Tibetan Plateau. The PM method produced reliable results when available data were sufficient, and the HS method proved to be a complementary method when variables were insufficient. On the contrary, the MG method always underestimated ET and is, thus, not suitable for alpine meadows. These results provide a basis for estimating ET on the Tibetan Plateau for annual data collection, analysis, and future studies.
Tipo de publicação: COMPARATIVE STUDY; JOURNAL ARTICLE


  9 / 1902 MEDLINE  
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PMID:28742981
Autor:Han C; Wang Z; Si G; Lei T; Yuan Y; Zhang G
Endereço:a Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, People's Republic of China.
Título:Increased precipitation accelerates soil organic matter turnover associated with microbial community composition in topsoil of alpine grassland on the eastern Tibetan Plateau.
Fonte:Can J Microbiol; 63(10):811-821, 2017 Oct.
ISSN:1480-3275
País de publicação:Canada
Idioma:eng
Resumo:Large quantities of carbon are stored in alpine grassland of the Tibetan Plateau, which is extremely sensitive to climate change. However, it remains unclear whether soil organic matter (SOM) in different layers responds to climate change analogously, and whether microbial communities play vital roles in SOM turnover of topsoil. In this study we measured and collected SOM turnover by the C method in alpine grassland to test climatic effects on SOM turnover in soil profiles. Edaphic properties and microbial communities in the northwestern Qinghai Lake were investigated to explore microbial influence on SOM turnover. SOM turnover in surface soil (0-10 cm) was more sensitive to precipitation than that in subsurface layers (10-40 cm). Precipitation also imposed stronger effects on the composition of microbial communities in the surface layer than that in deeper soil. At the 5-10 cm depth, the SOM turnover rate was positively associated with the bacteria/fungi biomass ratio and the relative abundance of Acidobacteria, both of which are related to precipitation. Partial correlation analysis suggested that increased precipitation could accelerate the SOM turnover rate in topsoil by structuring soil microbial communities. Conversely, carbon stored in deep soil would be barely affected by climate change. Our results provide valuable insights into the dynamics and storage of SOM in alpine grasslands under future climate scenarios.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Soil); 7440-44-0 (Carbon)


  10 / 1902 MEDLINE  
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PMID:29186199
Autor:Bao W; Wuyun T; Li T; Liu H; Jiang Z; Zhu X; Du H; Bai YE
Endereço:Non-Timber Forest Research and Development Center, Chinese Academy of Forestry, Zhengzhou, Henan, People's Republic of China.
Título:Genetic diversity and population structure of Prunus mira (Koehne) from the Tibet plateau in China and recommended conservation strategies.
Fonte:PLoS One; 12(11):e0188685, 2017.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:Prunus mira Koehne, an important economic fruit crop with high breeding and medicinal values, and an ancestral species of many cultivated peach species, has recently been declared an endangered species. However, basic information about genetic diversity, population structure, and morphological variation is still limited for this species. In this study, we sampled 420 P. mira individuals from 21 wild populations in the Tibet plateau to conduct a comprehensive analysis of genetic and morphological characteristics. The results of molecular analyses based on simple sequence repeat (SSR) markers indicated moderate genetic diversity and inbreeding (A = 3.8, Ae = 2.5, He = 0.52, Ho = 0.44, I = 0.95, FIS = 0.17) within P. mira populations. STRUCTURE, GENELAND, and phylogenetic analyses assigned the 21 populations to three genetic clusters that were moderately correlated with geographic altitudes, and this may have resulted from significantly different climatic and environmental factors at different altitudinal ranges. Significant isolation-by-distance was detected across the entire distribution of P. mira populations, but geographic altitude might have more significant effects on genetic structure than geographic distance in partial small-scale areas. Furthermore, clear genetic structure, high genetic differentiation, and restricted gene flow were detected between pairwise populations from different geographic groups, indicating that geographic barriers and genetic drift have significant effects on P. mira populations. Analyses of molecular variance based on the SSR markers indicated high variation (83.7% and 81.7%), whereas morphological analyses revealed low variation (1.30%-36.17%) within the populations. Large and heavy fruits were better adapted than light fruits and nutlets to poor climate and environmental conditions at high altitudes. Based on the results of molecular and morphological analyses, we classified the area into three conservation units and proposed several conservation strategies for wild P. mira populations in the Tibet plateau.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (DNA, Plant); 0 (Genetic Markers)



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