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排序方式: 共有142条查询结果,搜索用时 15 毫秒
111.
Broderick P Carvajal-Carmona L Pittman AM Webb E Howarth K Rowan A Lubbe S Spain S Sullivan K Fielding S Jaeger E Vijayakrishnan J Kemp Z Gorman M Chandler I Papaemmanuil E Penegar S Wood W Sellick G Qureshi M Teixeira A Domingo E Barclay E Martin L Sieber O;CORGI Consortium Kerr D Gray R Peto J Cazier JB Tomlinson I Houlston RS 《Nature genetics》2007,39(11):1315-1317
To identify risk variants for colorectal cancer (CRC), we conducted a genome-wide association study, genotyping 550,163 tag SNPs in 940 individuals with familial colorectal tumor (627 CRC, 313 advanced adenomas) and 965 controls. We evaluated selected SNPs in three replication sample sets (7,473 cases, 5,984 controls) and identified three SNPs in SMAD7 (involved in TGF-beta and Wnt signaling) associated with CRC. Across the four sample sets, the association between rs4939827 and CRC was highly statistically significant (P(trend) = 1.0 x 10(-12)). 相似文献
112.
Ludovic Dume′ e Aaron Thornton Kallista Sears Ju¨ rg Schu¨ tz Niall Finn Steven Spoljari Robert Shanks Chris Skourtis Mikel Duke Stephen Gray 《自然科学进展(英文版)》2012,22(6):673-683
In-situ thermal expansion tests on a series of carbon nanotube bucky-paper composites
were performed with direct heating within a synchrotron SAXS source. The impact of the samples
density and morphology as well as the chemistry and degree of decoration of the carbon nanotubes
on the scattering patterns were investigated and correlated to the materials macro-properties. The
results demonstrate that simple densification techniques, such as acetone dipping or gold electroless
deposition, could reduce greatly the displacements of the carbon nanotubes within the structure
and lead to more thermally stable material. 相似文献
113.
Chalasani SH Chronis N Tsunozaki M Gray JM Ramot D Goodman MB Bargmann CI 《Nature》2007,450(7166):63-70
Although many properties of the nervous system are shared among animals and systems, it is not known whether different neuronal circuits use common strategies to guide behaviour. Here we characterize information processing by Caenorhabditis elegans olfactory neurons (AWC) and interneurons (AIB and AIY) that control food- and odour-evoked behaviours. Using calcium imaging and mutations that affect specific neuronal connections, we show that AWC neurons are activated by odour removal and activate the AIB interneurons through AMPA-type glutamate receptors. The level of calcium in AIB interneurons is elevated for several minutes after odour removal, a neuronal correlate to the prolonged behavioural response to odour withdrawal. The AWC neuron inhibits AIY interneurons through glutamate-gated chloride channels; odour presentation relieves this inhibition and results in activation of AIY interneurons. The opposite regulation of AIY and AIB interneurons generates a coordinated behavioural response. Information processing by this circuit resembles information flow from vertebrate photoreceptors to 'OFF' bipolar and 'ON' bipolar neurons, indicating a conserved or convergent strategy for sensory information processing. 相似文献
114.
115.
A genome-wide association scan of tag SNPs identifies a susceptibility variant for colorectal cancer at 8q24.21 总被引:16,自引:0,他引:16
Tomlinson I Webb E Carvajal-Carmona L Broderick P Kemp Z Spain S Penegar S Chandler I Gorman M Wood W Barclay E Lubbe S Martin L Sellick G Jaeger E Hubner R Wild R Rowan A Fielding S Howarth K;CORGI Consortium Silver A Atkin W Muir K Logan R Kerr D Johnstone E Sieber O Gray R Thomas H Peto J Cazier JB Houlston R 《Nature genetics》2007,39(8):984-988
Much of the variation in inherited risk of colorectal cancer (CRC) is probably due to combinations of common low risk variants. We conducted a genome-wide association study of 550,000 tag SNPs in 930 familial colorectal tumor cases and 960 controls. The most strongly associated SNP (P = 1.72 x 10(-7), allelic test) was rs6983267 at 8q24.21. To validate this finding, we genotyped rs6983267 in three additional CRC case-control series (4,361 affected individuals and 3,752 controls; 1,901 affected individuals and 1,079 controls; 1,072 affected individuals and 415 controls) and replicated the association, providing P = 1.27 x 10(-14) (allelic test) overall, with odds ratios (ORs) of 1.27 (95% confidence interval (c.i.): 1.16-1.39) and 1.47 (95% c.i.: 1.34-1.62) for heterozygotes and rare homozygotes, respectively. Analyses based on 1,477 individuals with colorectal adenoma and 2,136 controls suggest that susceptibility to CRC is mediated through development of adenomas (OR = 1.21, 95% c.i.: 1.10-1.34; P = 6.89 x 10(-5)). These data show that common, low-penetrance susceptibility alleles predispose to colorectal neoplasia. 相似文献
116.
Assembly of microarrays for genome-wide measurement of DNA copy number. 总被引:20,自引:0,他引:20
A M Snijders N Nowak R Segraves S Blackwood N Brown J Conroy G Hamilton A K Hindle B Huey K Kimura S Law K Myambo J Palmer B Ylstra J P Yue J W Gray A N Jain D Pinkel D G Albertson 《Nature genetics》2001,29(3):263-264
We have assembled arrays of approximately 2,400 BAC clones for measurement of DNA copy number across the human genome. The arrays provide precise measurement (s.d. of log2 ratios=0.05-0.10) in cell lines and clinical material, so that we can reliably detect and quantify high-level amplifications and single-copy alterations in diploid, polyploid and heterogeneous backgrounds. 相似文献
117.
An apparently transient elevation of basal morning (08.00 h) plasma corticosterone levels in male mice was found 48 h after bilateral electrolytic lesions of the brainstem locus coeruleus complex but was not observed 6 weeks after lesioning. 相似文献
118.
(ADP-ribose)n participates in DNA excision repair 总被引:43,自引:0,他引:43
Chromatin proteins are covalently modified by at least five different processes; in no case has the precise physiological function been established. One of these post-synthetic, covalent modifications is effected by the enzyme poly(ADP-ribose) polymerase, which uses the coenzyme NAD+ to ADP-ribosylate chromatin proteins. The modification consists largely of mono(ADP-ribose), but long, homopolymer chains of (ADP-ribose) are also present. Various physiological functions have been suggested for (ADP-ribose)n. Here we demonstrate that one function of (ADP-ribose)n is to participate in the cellular recovery from DNA damage. Specific inhibitors of poly(ADP-ribose) polymerase prevent rejoining of DNA strand breaks caused by dimethyl sulphate and cytotoxicity is enhanced thereby. The rejoining of strand breaks is prevented also by nutritionally depleting the cells of NAD. 相似文献
119.
Summary Fluids from small (FF-S) and large (FF-L) bovine ovarian follicles were observed electrophoretically for differences in the alpha-globulin protein profile. FF-L possessed a fast migrating alpha-globulin 3 and a greater percentage of FF-L samples contained a higher number of alpha-globulin bands.This study was supported by a grant from the United States Department of Agriculture/Cooperative State Research Service (No. 616-15-138). 相似文献
120.
Sarah D. Gray 《Cellular and molecular life sciences : CMLS》1976,32(3):350-351
Summary Isometric tension was measured in arterial strips from neonatal lambs and adult sheep, after stimulation by angiotensin II. During the early maturation period immediately following birth (3 weeks) there was a progressive increase in sensitivity to the agent.This study was supported by the Golden Empire Chapter of the American Heart Association and the United States Public Health Service, grant No. PHS HL 14780-03. 相似文献