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排序方式: 共有215条查询结果,搜索用时 31 毫秒
51.
Lawrence C 《Annals of science》2007,64(1):101-106
52.
Manning AK Hivert MF Scott RA Grimsby JL Bouatia-Naji N Chen H Rybin D Liu CT Bielak LF Prokopenko I Amin N Barnes D Cadby G Hottenga JJ Ingelsson E Jackson AU Johnson T Kanoni S Ladenvall C Lagou V Lahti J Lecoeur C Liu Y Martinez-Larrad MT Montasser ME Navarro P Perry JR Rasmussen-Torvik LJ Salo P Sattar N Shungin D Strawbridge RJ Tanaka T van Duijn CM An P de Andrade M Andrews JS Aspelund T Atalay M Aulchenko Y Balkau B Bandinelli S Beckmann JS Beilby JP Bellis C Bergman RN Blangero J 《Nature genetics》2012,44(6):659-669
Recent genome-wide association studies have described many loci implicated in type 2 diabetes (T2D) pathophysiology and β-cell dysfunction but have contributed little to the understanding of the genetic basis of insulin resistance. We hypothesized that genes implicated in insulin resistance pathways might be uncovered by accounting for differences in body mass index (BMI) and potential interactions between BMI and genetic variants. We applied a joint meta-analysis approach to test associations with fasting insulin and glucose on a genome-wide scale. We present six previously unknown loci associated with fasting insulin at P < 5 × 10(-8) in combined discovery and follow-up analyses of 52 studies comprising up to 96,496 non-diabetic individuals. Risk variants were associated with higher triglyceride and lower high-density lipoprotein (HDL) cholesterol levels, suggesting a role for these loci in insulin resistance pathways. The discovery of these loci will aid further characterization of the role of insulin resistance in T2D pathophysiology. 相似文献
53.
One species of copepod ( Ergasilus elongatus ), one trematode ( Diclybothrium hamulatum ), two nematodes ( Camallanus oxycephalus and Contracaecum sp.), and two cestodes ( Marsipometra hastata and M. parva ) were recovered from 17 paddlefish ( Polyodon spathula ) collected from the Yellowstone River, Montana, on 11 and 18 May 1973. The male paddlefish averaged 69.4 nematodes and 157.6 cestodes per infected fish while the females averaged 12.0 nematodes and 415.7 cestodes. The higher intensity of cestode infection in female paddlefish was attributed to their larger size and consequent greater intake of food resulting in more exposure to the cestode intermediate hosts ( Cyclops bicuspidatus ). 相似文献
54.
Höglinger GU Melhem NM Dickson DW Sleiman PM Wang LS Klei L Rademakers R de Silva R Litvan I Riley DE van Swieten JC Heutink P Wszolek ZK Uitti RJ Vandrovcova J Hurtig HI Gross RG Maetzler W Goldwurm S Tolosa E Borroni B Pastor P;PSP Genetics Study Group Cantwell LB Han MR Dillman A van der Brug MP Gibbs JR Cookson MR Hernandez DG Singleton AB Farrer MJ Yu CE Golbe LI Revesz T Hardy J Lees AJ Devlin B Hakonarson H Müller U Schellenberg GD 《Nature genetics》2011,43(7):699-705
Progressive supranuclear palsy (PSP) is a movement disorder with prominent tau neuropathology. Brain diseases with abnormal tau deposits are called tauopathies, the most common of which is Alzheimer's disease. Environmental causes of tauopathies include repetitive head trauma associated with some sports. To identify common genetic variation contributing to risk for tauopathies, we carried out a genome-wide association study of 1,114 individuals with PSP (cases) and 3,247 controls (stage 1) followed by a second stage in which we genotyped 1,051 cases and 3,560 controls for the stage 1 SNPs that yielded P ≤ 10(-3). We found significant previously unidentified signals (P < 5 × 10(-8)) associated with PSP risk at STX6, EIF2AK3 and MOBP. We confirmed two independent variants in MAPT affecting risk for PSP, one of which influences MAPT brain expression. The genes implicated encode proteins for vesicle-membrane fusion at the Golgi-endosomal interface, for the endoplasmic reticulum unfolded protein response and for a myelin structural component. 相似文献
55.
Bass AJ Lawrence MS Brace LE Ramos AH Drier Y Cibulskis K Sougnez C Voet D Saksena G Sivachenko A Jing R Parkin M Pugh T Verhaak RG Stransky N Boutin AT Barretina J Solit DB Vakiani E Shao W Mishina Y Warmuth M Jimenez J Chiang DY Signoretti S Kaelin WG Spardy N Hahn WC Hoshida Y Ogino S Depinho RA Chin L Garraway LA Fuchs CS Baselga J Tabernero J Gabriel S Lander ES Getz G Meyerson M 《Nature genetics》2011,43(10):964-968
Prior studies have identified recurrent oncogenic mutations in colorectal adenocarcinoma and have surveyed exons of protein-coding genes for mutations in 11 affected individuals. Here we report whole-genome sequencing from nine individuals with colorectal cancer, including primary colorectal tumors and matched adjacent non-tumor tissues, at an average of 30.7× and 31.9× coverage, respectively. We identify an average of 75 somatic rearrangements per tumor, including complex networks of translocations between pairs of chromosomes. Eleven rearrangements encode predicted in-frame fusion proteins, including a fusion of VTI1A and TCF7L2 found in 3 out of 97 colorectal cancers. Although TCF7L2 encodes TCF4, which cooperates with β-catenin in colorectal carcinogenesis, the fusion lacks the TCF4 β-catenin-binding domain. We found a colorectal carcinoma cell line harboring the fusion gene to be dependent on VTI1A-TCF7L2 for anchorage-independent growth using RNA interference-mediated knockdown. This study shows previously unidentified levels of genomic rearrangements in colorectal carcinoma that can lead to essential gene fusions and other oncogenic events. 相似文献
56.
57.
Xlr3b is a new imprinted candidate for X-linked parent-of-origin effects on cognitive function in mice 总被引:5,自引:0,他引:5
Davies W Isles A Smith R Karunadasa D Burrmann D Humby T Ojarikre O Biggin C Skuse D Burgoyne P Wilkinson L 《Nature genetics》2005,37(6):625-629
Imprinted genes show differential expression between maternal and paternal alleles as a consequence of epigenetic modification that can result in 'parent-of-origin' effects on phenotypic traits. There is increasing evidence from mouse and human studies that imprinted genes may influence behavior and cognitive functioning. Previous work in girls with Turner syndrome (45,XO) has suggested that there are X-linked parent-of-origin effects on brain development and cognitive functioning, although the interpretation of these data in terms of imprinted gene effects has been questioned. We used a 39,XO mouse model to examine the influence of the parental origin of the X chromosome on cognitive behaviors and expression of X-linked genes in brain. Our findings confirm the existence of X-linked imprinted effects on cognitive processes and identify a new maternally expressed imprinted gene candidate on the X chromosome, Xlr3b, which may be of importance in mediating the behavioral effects. 相似文献
58.
Haskin LA Wang A Jolliff BL McSween HY Clark BC Des Marais DJ McLennan SM Tosca NJ Hurowitz JA Farmer JD Yen A Squyres SW Arvidson RE Klingelhöfer G Schröder C de Souza PA Ming DW Gellert R Zipfel J Brückner J Bell JF Herkenhoff K Christensen PR Ruff S Blaney D Gorevan S Cabrol NA Crumpler L Grant J Soderblom L 《Nature》2005,436(7047):66-69
Gusev crater was selected as the landing site for the Spirit rover because of the possibility that it once held a lake. Thus one of the rover's tasks was to search for evidence of lake sediments. However, the plains at the landing site were found to be covered by a regolith composed of olivine-rich basaltic rock and windblown 'global' dust. The analyses of three rock interiors exposed by the rock abrasion tool showed that they are similar to one another, consistent with having originated from a common lava flow. Here we report the investigation of soils, rock coatings and rock interiors by the Spirit rover from sol (martian day) 1 to sol 156, from its landing site to the base of the Columbia hills. The physical and chemical characteristics of the materials analysed provide evidence for limited but unequivocal interaction between water and the volcanic rocks of the Gusev plains. This evidence includes the softness of rock interiors that contain anomalously high concentrations of sulphur, chlorine and bromine relative to terrestrial basalts and martian meteorites; sulphur, chlorine and ferric iron enrichments in multilayer coatings on the light-toned rock Mazatzal; high bromine concentration in filled vugs and veins within the plains basalts; positive correlations between magnesium, sulphur and other salt components in trench soils; and decoupling of sulphur, chlorine and bromine concentrations in trench soils compared to Gusev surface soils, indicating chemical mobility and separation. 相似文献
59.
Karkkainen MJ Ferrell RE Lawrence EC Kimak MA Levinson KL McTigue MA Alitalo K Finegold DN 《Nature genetics》2000,25(2):153-159
Primary lymphoedema is a rare, autosomal dominant disorder that leads to a disabling and disfiguring swelling of the extremities and, when untreated, tends to worsen with time. Here we link primary human lymphoedema to the FLT4 locus, encoding vascular endothelial growth factor receptor-3 (VEGFR-3), in several families. All disease-associated alleles analysed had missense mutations and encoded proteins with an inactive tyrosine kinase, preventing downstream gene activation. Our study establishes that VEGFR-3 is important for normal lymphatic vascular function and that mutations interfering with VEGFR-3 signal transduction are a cause of primary lymphoedema. 相似文献
60.
Near-Earth asteroids are small (diameters < 10 km), rocky bodies with orbits that approach that of the Earth (they come within 1.3 AU of the Sun). Most have a chance of approximately 0.5% of colliding with the Earth in the next million years. The total number of such bodies with diameters > 1 km has been estimated to be in the range 1,000-2,000, which translates to an approximately 1% chance of a catastrophic collision with the Earth in the next millennium. These numbers are, however, poorly constrained because of the limitations of previous searches using photographic plates. (One kilometre is below the size of a body whose impact on the Earth would produce global effects.) Here we report an analysis of our survey for near-Earth asteroids that uses improved detection technologies. We find that the total number of asteroids with diameters > 1 km is about half the earlier estimates. At the current rate of discovery of near-Earth asteroids, 90% will probably have been detected within the next 20 years. 相似文献