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排序方式: 共有462条查询结果,搜索用时 15 毫秒
211.
Pimm SL Ayres M Balmford A Branch G Brandon K Brooks T Bustamante R Costanza R Cowling R Curran LM Dobson A Farber S da Fonseca GA Gascon C Kitching R McNeely J Lovejoy T Mittermeier RA Myers N Patz JA Raffle B Rapport D Raven P Roberts C Rodriguez JP Rylands AB Tucker C Safina C Samper C Stiassny ML Supriatna J Wall DH Wilcove D 《Science (New York, N.Y.)》2001,293(5538):2207-2208
212.
Myers A Holmans P Marshall H Kwon J Meyer D Ramic D Shears S Booth J DeVrieze FW Crook R Hamshere M Abraham R Tunstall N Rice F Carty S Lillystone S Kehoe P Rudrasingham V Jones L Lovestone S Perez-Tur J Williams J Owen MJ Hardy J Goate AM 《Science (New York, N.Y.)》2000,290(5500):2304-2305
The apolipoprotein E (APOE) gene is the only genetic risk factor that has so far been linked to risk for late-onset Alzheimer's disease (LOAD). However, 50 percent of Alzheimer's disease cases do not carry an APOE4 allele, suggesting that other risk factors must exist. We performed a two-stage genome-wide screen in sibling pairs with LOAD to detect other susceptibility loci. Here we report evidence for an Alzheimer's disease locus on chromosome 10. Our stage one multipoint lod score (logarithm of the odds ratio for linkage/no linkage) of 2.48 (266 sibling pairs) increased to 3.83 in stage 2 (429 sibling pairs) close to D10S1225 (79 centimorgans). This locus modifies risk for Alzheimer's disease independent of APOE genotype. 相似文献
213.
Ogunsanya TJ Durborow RM Myers ML Cole HP Thompson SL 《Journal of agricultural safety and health》2011,17(1):33-61
The objective of this study was to identify and describe work-related safety hazards, injuries, and near-injury events (close calls) that occurred on trout farms in North Carolina and Kentucky. An interview instrument was used to collect information on occupational hazards, injuries, and near-injury events that resulted from work-related activities. Trout farmers reported occupational hazards including falling live tank lids, slippery surfaces on hauling trucks, lifting strains, falls from raceway walls and walkways, needlesticks while vaccinating fish, allergies, hypothermia/drowning, falls from cranes, chemical exposure, fire/explosions related to oxygen exposure, and electrical contact with overhead power lines. This study also reports solutions suggested by farm safety researchers or used by farmers to prevent the safety hazards found on trout farms. 相似文献
214.
Detection of single base substitutions by ribonuclease cleavage at mismatches in RNA:DNA duplexes 总被引:89,自引:0,他引:89
Single base substitutions can be detected and localized by a simple and rapid method that involves ribonuclease cleavage of single base mismatches in RNA:DNA heteroduplexes. A 32P-labeled RNA probe complementary to wild-type DNA is synthesized in vitro and annealed to a test DNA containing a single base substitution. The resulting single base mismatch is cleaved by ribonuclease A, and the location of the mismatch is then determined by analyzing the sizes of the cleavage products by gel electrophoresis. Analysis of every type of mismatch in many different sequence contexts indicates that more than 50 percent of all single base substitutions can be detected. The feasibility of this method for localizing base substitutions directly in genomic DNA samples is demonstrated by the detection of single base mutations in DNA obtained from individuals with beta-thalassemia, a genetic disorder in beta-globin gene expression. 相似文献
215.
Monkeys injected with monkey retinal tissue incorporated in Freunld's complete adjuvant developed ocular lesions characterized by choroiditic patches in the fundus periphery and sheathing of retinal vessels. Bovine retina, monkey choroid plexus, and guinea pig kidney were ineffective in this respect. 相似文献
216.
217.
218.
A comparison of whole-genome shotgun-derived mouse chromosome 16 and the human genome 总被引:1,自引:0,他引:1
Mural RJ Adams MD Myers EW Smith HO Miklos GL Wides R Halpern A Li PW Sutton GG Nadeau J Salzberg SL Holt RA Kodira CD Lu F Chen L Deng Z Evangelista CC Gan W Heiman TJ Li J Li Z Merkulov GV Milshina NV Naik AK Qi R Shue BC Wang A Wang J Wang X Yan X Ye J Yooseph S Zhao Q Zheng L Zhu SC Biddick K Bolanos R Delcher AL Dew IM Fasulo D Flanigan MJ Huson DH Kravitz SA Miller JR Mobarry CM Reinert K Remington KA Zhang Q Zheng XH Nusskern DR Lai Z Lei Y Zhong W Yao A Guan P Ji RR Gu Z Wang ZY Zhong F 《Science (New York, N.Y.)》2002,296(5573):1661-1671
The high degree of similarity between the mouse and human genomes is demonstrated through analysis of the sequence of mouse chromosome 16 (Mmu 16), which was obtained as part of a whole-genome shotgun assembly of the mouse genome. The mouse genome is about 10% smaller than the human genome, owing to a lower repetitive DNA content. Comparison of the structure and protein-coding potential of Mmu 16 with that of the homologous segments of the human genome identifies regions of conserved synteny with human chromosomes (Hsa) 3, 8, 12, 16, 21, and 22. Gene content and order are highly conserved between Mmu 16 and the syntenic blocks of the human genome. Of the 731 predicted genes on Mmu 16, 509 align with orthologs on the corresponding portions of the human genome, 44 are likely paralogous to these genes, and 164 genes have homologs elsewhere in the human genome; there are 14 genes for which we could find no human counterpart. 相似文献
219.
Electrical field-flow fractionation of proteins 总被引:3,自引:0,他引:3
Protein separation has been achieved by electrical field-flow fractionation, a heretofore unrealized separation technique. Some advantages of this method relative to electrophoresis are the low voltage required, the lack of adverse heating and support effects, and the existence of the method as an elution technique. A comparison of theoretical and experimental retention shows good agreement. 相似文献
220.
Lobert JM Butler JH Montzka SA Geller LS Myers RC Elkins JW 《Science (New York, N.Y.)》1995,267(5200):1002-1005
Surface waters along a cruise track in the East Pacific Ocean were undersaturated in methyl bromide (CH(3)Br) in most areas except for coastal and upwelling regions, with saturation anomalies ranging from + 100 percent in coastal waters to -50 percent in open ocean areas, representing a regionally weighted mean of -16 (-13 to -20) percent. The partial lifetime of atmospheric CH(3)Br with respect to calculated oceanic degradation along this cruise track is 3.0 (2.9 to 3.6) years. The global, mean dry mole fraction of CH3Br in the atmosphere was 9.8 +/- 0.6 parts per trillion, with an interhemispheric ratio of 1.31 +/- 0.08. These data indicate that approximately 8 percent (0.2 parts per trillion) of the observed interhemispheric difference in atmospheric CH3Br could be attributed to an uneven global distribution of oceanic sources and sinks. 相似文献