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排序方式: 共有288条查询结果,搜索用时 15 毫秒
81.
Y Okada X Sim MJ Go JY Wu D Gu F Takeuchi A Takahashi S Maeda T Tsunoda P Chen SC Lim TY Wong J Liu TL Young T Aung M Seielstad YY Teo YJ Kim JY Lee BG Han D Kang CH Chen FJ Tsai LC Chang SJ Fann H Mei DC Rao JE Hixson S Chen T Katsuya M Isono T Ogihara JC Chambers W Zhang JS Kooner;KidneyGen Consortium;CKDGen Consortium E Albrecht;GUGC consortium K Yamamoto M Kubo Y Nakamura N Kamatani N Kato J He YT Chen YS Cho ES Tai T Tanaka 《Nature genetics》2012,44(8):904-909
Chronic kidney disease (CKD), impairment of kidney function, is a serious public health problem, and the assessment of genetic factors influencing kidney function has substantial clinical relevance. Here, we report a meta-analysis of genome-wide association studies for kidney function-related traits, including 71,149 east Asian individuals from 18 studies in 11 population-, hospital- or family-based cohorts, conducted as part of the Asian Genetic Epidemiology Network (AGEN). Our meta-analysis identified 17 loci newly associated with kidney function-related traits, including the concentrations of blood urea nitrogen, uric acid and serum creatinine and estimated glomerular filtration rate based on serum creatinine levels (eGFRcrea) (P < 5.0 × 10(-8)). We further examined these loci with in silico replication in individuals of European ancestry from the KidneyGen, CKDGen and GUGC consortia, including a combined total of ~110,347 individuals. We identify pleiotropic associations among these loci with kidney function-related traits and risk of CKD. These findings provide new insights into the genetics of kidney function. 相似文献
82.
Raychaudhuri S Remmers EF Lee AT Hackett R Guiducci C Burtt NP Gianniny L Korman BD Padyukov L Kurreeman FA Chang M Catanese JJ Ding B Wong S van der Helm-van Mil AH Neale BM Coblyn J Cui J Tak PP Wolbink GJ Crusius JB van der Horst-Bruinsma IE Criswell LA Amos CI Seldin MF Kastner DL Ardlie KG Alfredsson L Costenbader KH Altshuler D Huizinga TW Shadick NA Weinblatt ME de Vries N Worthington J Seielstad M Toes RE Karlson EW Begovich AB Klareskog L Gregersen PK Daly MJ Plenge RM 《Nature genetics》2008,40(10):1216-1223
To identify rheumatoid arthritis risk loci in European populations, we conducted a meta-analysis of two published genome-wide association (GWA) studies totaling 3,393 cases and 12,462 controls. We genotyped 31 top-ranked SNPs not previously associated with rheumatoid arthritis in an independent replication of 3,929 autoantibody-positive rheumatoid arthritis cases and 5,807 matched controls from eight separate collections. We identified a common variant at the CD40 gene locus (rs4810485, P = 0.0032 replication, P = 8.2 x 10(-9) overall, OR = 0.87). Along with other associations near TRAF1 (refs. 2,3) and TNFAIP3 (refs. 4,5), this implies a central role for the CD40 signaling pathway in rheumatoid arthritis pathogenesis. We also identified association at the CCL21 gene locus (rs2812378, P = 0.00097 replication, P = 2.8 x 10(-7) overall), a gene involved in lymphocyte trafficking. Finally, we identified evidence of association at four additional gene loci: MMEL1-TNFRSF14 (rs3890745, P = 0.0035 replication, P = 1.1 x 10(-7) overall), CDK6 (rs42041, P = 0.010 replication, P = 4.0 x 10(-6) overall), PRKCQ (rs4750316, P = 0.0078 replication, P = 4.4 x 10(-6) overall), and KIF5A-PIP4K2C (rs1678542, P = 0.0026 replication, P = 8.8 x 10(-8) overall). 相似文献
83.
Adaptive Under-Frequency Load Shedding 总被引:1,自引:0,他引:1
Under-frequency load shedding (UFLS) is used in the power industry to rescue systems facing extreme disturbances to avoid system collapse. Traditionally, many computations are repeated to seek the proper power system settings such that the UFLS provides the desired good performance for selected scenarios. An adaptive UFLS method based on the genetic algorithm was developed to automate the finding of optimal parameters to minimize the repetitive trial-error calculations. Simulations demonstrate that the method has better performance than previous schemes and reduces the time and effort of the repetitive simulations. 相似文献
84.
This review article describes new enzymatic methods developed for the efficient and irreversible synthesis of peptides based on native and modified proteases, and for the synthesis of polypeptides containing D- and/or unnatural amino acids. Potential opportunities for future developments in the field based on new enzymes, tailormade catalytic antibodies, and on the technique of in vitro mutagenesis are also described. 相似文献
85.
1,2,4-Triazolidine-3,5-diones and the 3,5-isoxazolidinedione were observed to be potent inhibitors of rat lens aldose reductase activity. In vivo in streptozotocin-diabetic rats, selected agents at 20 mg/kg/day, orally for 21 days reduced significantly the sorbitol levels of rbc, lens and sciatic nerves, suggesting that these derivatives may have some usefulness to treat clinical complications of diabetes mellitus. 相似文献
86.
Complete genome sequence of Pseudomonas aeruginosa PAO1, an opportunistic pathogen 总被引:45,自引:0,他引:45
Stover CK Pham XQ Erwin AL Mizoguchi SD Warrener P Hickey MJ Brinkman FS Hufnagle WO Kowalik DJ Lagrou M Garber RL Goltry L Tolentino E Westbrock-Wadman S Yuan Y Brody LL Coulter SN Folger KR Kas A Larbig K Lim R Smith K Spencer D Wong GK Wu Z Paulsen IT Reizer J Saier MH Hancock RE Lory S Olson MV 《Nature》2000,406(6799):959-964
Pseudomonas aeruginosa is a ubiquitous environmental bacterium that is one of the top three causes of opportunistic human infections. A major factor in its prominence as a pathogen is its intrinsic resistance to antibiotics and disinfectants. Here we report the complete sequence of P. aeruginosa strain PAO1. At 6.3 million base pairs, this is the largest bacterial genome sequenced, and the sequence provides insights into the basis of the versatility and intrinsic drug resistance of P. aeruginosa. Consistent with its larger genome size and environmental adaptability, P. aeruginosa contains the highest proportion of regulatory genes observed for a bacterial genome and a large number of genes involved in the catabolism, transport and efflux of organic compounds as well as four potential chemotaxis systems. We propose that the size and complexity of the P. aeruginosa genome reflect an evolutionary adaptation permitting it to thrive in diverse environments and resist the effects of a variety of antimicrobial substances. 相似文献
87.
The optical, electronic and mechanical properties of synthetic and biological materials consisting of polymer chains depend sensitively on the conformation adopted by these chains. The range of conformations available to such systems has accordingly been of intense fundamental as well as practical interest, and distinct conformational classes have been predicted, depending on the stiffness of the polymer chains and the strength of attractive interactions between segments within a chain. For example, flexible polymers should adopt highly disordered conformations resembling either a random coil or, in the presence of strong intrachain attractions, a so-called 'molten globule'. Stiff polymers with strong intrachain interactions, in contrast, are expected to collapse into conformations with long-range order, in the shape of toroids or rod-like structures. Here we use computer simulations to show that the anisotropy distribution obtained from polarization spectroscopy measurements on individual poly[2-methoxy-5-(2'-ethylhexyl)oxy-1,4-phenylenevinylene] polymer molecules is consistent with this prototypical stiff conjugated polymer adopting a highly ordered, collapsed conformation that cannot be correlated with ideal toroid or rod structures. We find that the presence of so-called 'tetrahedral chemical defects', where conjugated carbon-carbon links are replaced by tetrahedral links, divides the polymer chain into structurally identifiable quasi-straight segments that allow the molecule to adopt cylindrical conformations. Indeed, highly ordered, cylindrical conformations may be a critical factor in dictating the extraordinary photophysical properties of conjugated polymers, including highly efficient intramolecular energy transfer and significant local optical anisotropy in thin films. 相似文献
88.
Telomere dysfunction impairs DNA repair and enhances sensitivity to ionizing radiation 总被引:20,自引:0,他引:20
Wong KK Chang S Weiler SR Ganesan S Chaudhuri J Zhu C Artandi SE Rudolph KL Gottlieb GJ Chin L Alt FW DePinho RA 《Nature genetics》2000,26(1):85-88
Telomeres are specialized nucleoprotein complexes that serve as protective caps of linear eukaryotic chromosomes. Loss of telomere function is associated with rampant genetic instability and loss of cellular viability and renewal potential. The telomere also participates in processes of chromosomal repair, as evidenced by the 'capture' or de novo synthesis of telomere repeats at double-stranded breaks and by the capacity of yeast telomeres to serve as repositories of essential components of the DNA repair machinery, particularly those involved in non-homologous end-joining (NHEJ). Here we used the telomerase-deficient mouse, null for the essential telomerase RNA gene (Terc), to assess the role of telomerase and telomere function on the cellular and organismal response to ionizing radiation. Although the loss of telomerase activity per se had no discernable impact on the response to ionizing radiation, the emergence of telomere dysfunction in late-generation Terc-/- mice imparted a radiosensitivity syndrome associated with accelerated mortality. On the cellular level, the gastrointestinal crypt stem cells and primary thymocytes showed increased rates of apoptosis, and mouse embryonic fibroblasts (MEFs) showed diminished dose-dependent clonogenic survival. The radiosensitivity of telomere dysfunctional cells correlated with delayed DNA break repair kinetics, persistent chromosomal breaks and cytogenetic profiles characterized by complex chromosomal aberrations and massive fragmentation. Our findings establish a intimate relationship between functionally intact telomeres and the genomic, cellular and organismal response to ionizing radiation. 相似文献
89.
1 Introduction1 Preserving natural heritage has been identified as an important task in many countries. However, if damage to such heritage is unavoidable during the development, we may want to record the natural heritage before damaging it. One way is to acquire the 3D geometric information of the natural heritage. So that we can render it later. However, if the natural heritage is very large in scale and very complex in geometry, acquisition of such large-scale environment is infeasible an… 相似文献
90.