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排序方式: 共有210条查询结果,搜索用时 15 毫秒
171.
172.
Soler Artigas M Loth DW Wain LV Gharib SA Obeidat M Tang W Zhai G Zhao JH Smith AV Huffman JE Albrecht E Jackson CM Evans DM Cadby G Fornage M Manichaikul A Lopez LM Johnson T Aldrich MC Aspelund T Barroso I Campbell H Cassano PA Couper DJ Eiriksdottir G Franceschini N Garcia M Gieger C Gislason GK Grkovic I Hammond CJ Hancock DB Harris TB Ramasamy A Heckbert SR Heliövaara M Homuth G Hysi PG James AL Jankovic S Joubert BR Karrasch S Klopp N Koch B Kritchevsky SB Launer LJ Liu Y Loehr LR 《Nature genetics》2011,43(11):1082-1090
Pulmonary function measures reflect respiratory health and are used in the diagnosis of chronic obstructive pulmonary disease. We tested genome-wide association with forced expiratory volume in 1 second and the ratio of forced expiratory volume in 1 second to forced vital capacity in 48,201 individuals of European ancestry with follow up of the top associations in up to an additional 46,411 individuals. We identified new regions showing association (combined P < 5 × 10(-8)) with pulmonary function in or near MFAP2, TGFB2, HDAC4, RARB, MECOM (also known as EVI1), SPATA9, ARMC2, NCR3, ZKSCAN3, CDC123, C10orf11, LRP1, CCDC38, MMP15, CFDP1 and KCNE2. Identification of these 16 new loci may provide insight into the molecular mechanisms regulating pulmonary function and into molecular targets for future therapy to alleviate reduced lung function. 相似文献
173.
A survey of colony attributes and associated vertebrates on black - tail ( Cynomys ludovicianus ), Gunnison's ( C. gunnisoni ), and white - tail ( C. leucurus ) prairie dogs was made. A belt transect 1.6 km wide and 13,334 km long from Hobbs, New Mexico, to the Utah - Wyoming state line was surveyed. There were 47 colonies located (4760 ha comprising 2.2 percent) in the belt. Intercolony distances varied significantly. Three black - tail towns averaged 33 ha in area (SD = 26, range 10 – 61), II Gunnison's averaged 46 ha (SD = 43, range 16 – 150), and 33 white - tail towns averaged 125 ha (SD = 200, range 0.2 – 958). Badger activity was positively and significantly correlated to colony size and number of burrow openings on Gunnison's and white - tail towns. There were 107 vertebrate species and subspecies (one amphibian, 25 reptiles, 51 birds, 30 mammals) observed on prairie dog colonies. Results of our surveys are compared with prairie dog studies elsewhere. The role of prairie dogs and relationships to some vertebrates species are discussed. 相似文献
174.
Steinberg KM Antonacci F Sudmant PH Kidd JM Campbell CD Vives L Malig M Scheinfeldt L Beggs W Ibrahim M Lema G Nyambo TB Omar SA Bodo JM Froment A Donnelly MP Kidd KK Tishkoff SA Eichler EE 《Nature genetics》2012,44(8):872-880
The 17q21.31 inversion polymorphism exists either as direct (H1) or inverted (H2) haplotypes with differential predispositions to disease and selection. We investigated its genetic diversity in 2,700 individuals, with an emphasis on African populations. We characterize eight structural haplotypes due to complex rearrangements that vary in size from 1.08-1.49 Mb and provide evidence for a 30-kb H1-H2 double recombination event. We show that recurrent partial duplications of the KANSL1 gene have occurred on both the H1 and H2 haplotypes and have risen to high frequency in European populations. We identify a likely ancestral H2 haplotype (H2') lacking these duplications that is enriched among African hunter-gatherer groups yet essentially absent from West African populations. Whereas H1 and H2 segmental duplications arose independently and before human migration out of Africa, they have reached high frequencies recently among Europeans, either because of extraordinary genetic drift or selective sweeps. 相似文献
175.
Molecular cloning of cDNA for murine interleukin-3 总被引:51,自引:0,他引:51
M C Fung A J Hapel S Ymer D R Cohen R M Johnson H D Campbell I G Young 《Nature》1984,307(5948):233-237
The cDNA sequence for murine interleukin-3, one of the colony stimulating factors that regulate haematopoiesis, codes for a polypeptide of 166 amino acids including a putative signal peptide. The predicted amino acid sequence indicates that formation of mature interleukin-3 involves proteolytic removal of not only the signal peptide but additional amino-terminal amino acids. 相似文献
176.
177.
Xueming Yang Xiaoyong Yang Shuangxi Chen Tianhu Chen Peishan Zhang Kejie Tao M. J. Le Bas R. N. Wilson R. Branson L. S. Campbell T. C. Williams P. Henderson 《科学通报(英文版)》1999,44(15):1419-1419
Ba-REE fluorcarbonate minerals from a carbonatite dyke at Bayan Obo, Inner Mongolia, North China, are first reported in this
contribution, in which chemical composition, rare earth element (REE) patterns, and intergrowth relationships for these minerals
have been investigated. Syntactic intergrowth or syntaxy between cebaite and cordylite, as well as cordylite and huanghoite
were observed. This syntactic texture resulted from the variation of chemical composition of crystallizing agents for those
minerals that crystallized directly from carbonatite magmas. It is worth noting that REE patterns of the Ba-REE fluorcarbonate
minerals in the dyke are similar to those of the corresponding minerals from the ore hosted dolomite marble of the Bayan Obo
giant REE-Nb-Fe mineral deposit, which implies their relation in origin. 相似文献
178.
D Reich N Patterson D Campbell A Tandon S Mazieres N Ray MV Parra W Rojas C Duque N Mesa LF García O Triana S Blair A Maestre JC Dib CM Bravi G Bailliet D Corach T Hünemeier MC Bortolini FM Salzano ML Petzl-Erler V Acuña-Alonzo C Aguilar-Salinas S Canizales-Quinteros T Tusié-Luna L Riba M Rodríguez-Cruz M Lopez-Alarcón R Coral-Vazquez T Canto-Cetina I Silva-Zolezzi JC Fernandez-Lopez AV Contreras G Jimenez-Sanchez MJ Gómez-Vázquez J Molina A Carracedo A Salas C Gallo G Poletti DB Witonsky 《Nature》2012,488(7411):370-374
The peopling of the Americas has been the subject of extensive genetic, archaeological and linguistic research; however, central questions remain unresolved. One contentious issue is whether the settlement occurred by means of a single migration or multiple streams of migration from Siberia. The pattern of dispersals within the Americas is also poorly understood. To address these questions at a higher resolution than was previously possible, we assembled data from 52 Native American and 17 Siberian groups genotyped at 364,470 single nucleotide polymorphisms. Here we show that Native Americans descend from at least three streams of Asian gene flow. Most descend entirely from a single ancestral population that we call 'First American'. However, speakers of Eskimo-Aleut languages from the Arctic inherit almost half their ancestry from a second stream of Asian gene flow, and the Na-Dene-speaking Chipewyan from Canada inherit roughly one-tenth of their ancestry from a third stream. We show that the initial peopling followed a southward expansion facilitated by the coast, with sequential population splits and little gene flow after divergence, especially in South America. A major exception is in Chibchan speakers on both sides of the Panama isthmus, who have ancestry from both North and South America. 相似文献
179.
Diabetes in transgenic mice resulting from over-expression of class I histocompatibility molecules in pancreatic beta cells 总被引:20,自引:0,他引:20
A class I histocompatibility gene, H-2Kb, linked to the rat insulin promoter, is overexpressed in the pancreatic beta cells of transgenic mice. The mice, whether syngeneic or allogeneic to the transgene, develop insulin dependent diabetes without detectable T cell infiltration, suggesting a direct, non-immune role for the transgenic class I molecules in the disease process. 相似文献
180.