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排序方式: 共有301条查询结果,搜索用时 15 毫秒
81.
Reboul J Vaglio P Rual JF Lamesch P Martinez M Armstrong CM Li S Jacotot L Bertin N Janky R Moore T Hudson JR Hartley JL Brasch MA Vandenhaute J Boulton S Endress GA Jenna S Chevet E Papasotiropoulos V Tolias PP Ptacek J Snyder M Huang R Chance MR Lee H Doucette-Stamm L Hill DE Vidal M 《Nature genetics》2003,34(1):35-41
To verify the genome annotation and to create a resource to functionally characterize the proteome, we attempted to Gateway-clone all predicted protein-encoding open reading frames (ORFs), or the 'ORFeome,' of Caenorhabditis elegans. We successfully cloned approximately 12,000 ORFs (ORFeome 1.1), of which roughly 4,000 correspond to genes that are untouched by any cDNA or expressed-sequence tag (EST). More than 50% of predicted genes needed corrections in their intron-exon structures. Notably, approximately 11,000 C. elegans proteins can now be expressed under many conditions and characterized using various high-throughput strategies, including large-scale interactome mapping. We suggest that similar ORFeome projects will be valuable for other organisms, including humans. 相似文献
82.
Dicer is essential for mouse development 总被引:33,自引:0,他引:33
Bernstein E Kim SY Carmell MA Murchison EP Alcorn H Li MZ Mills AA Elledge SJ Anderson KV Hannon GJ 《Nature genetics》2003,35(3):215-217
To address the biological function of RNA interference (RNAi)-related pathways in mammals, we disrupted the gene Dicer1 in mice. Loss of Dicer1 lead to lethality early in development, with Dicer1-null embryos depleted of stem cells. Coupled with our inability to generate viable Dicer1-null embryonic stem (ES) cells, this suggests a role for Dicer, and, by implication, the RNAi machinery, in maintaining the stem cell population during early mouse development. 相似文献
83.
Protection of chimpanzees from infection by HIV-1 after vaccination with recombinant glycoprotein gp120 but not gp160 总被引:78,自引:0,他引:78
P W Berman T J Gregory L Riddle G R Nakamura M A Champe J P Porter F M Wurm R D Hershberg E K Cobb J W Eichberg 《Nature》1990,345(6276):622-625
The development of a vaccine to provide protective immunity to human immunodeficiency virus type 1 (HIV-1), the virus causing AIDS, would be the most practical method to control its spread. Subunit vaccines consisting of virus envelope glycoproteins, produced by recombinant DNA technology, are effective in preventing viral infections. We have now used this approach in the development of a candidate AIDS vaccine. Chimpanzees were immunized with recombinant forms of the HIV-1 glycoproteins gp120 and gp160 produced in Chinese hamster ovary cells, and then challenged with HIV-1. The control and the two animals immunized with the gp160 variant became infected within 7 weeks of challenge. The two animals immunized with the gp120 variant have shown no signs of infection after more than 6 months. These studies demonstrate that recombinant gp120, formulated in an adjuvant approved for human use, can elicit protective immunity against a homologous strain of HIV-1. 相似文献
84.
T cells can present antigens such as HIV gp120 targeted to their own surface molecules 总被引:22,自引:0,他引:22
To trigger class II-restricted T cells, antigen presenting cells have to capture antigens, process them and display their fragments in association with class II molecules. In most species, activated T cells express class II molecules; however, no evidence has been found that these cells can present soluble antigens. This failure may be due to the inefficient capture, processing or display of antigens in a stimulatory form by T-cells. The capture of a soluble antigen, which is achieved by nonspecific mechanisms in macrophages and dendritic cells, can be up to 10(3) times more efficient in the presence of surface receptors, such as surface immunoglobulin on B cells that specifically bind antigen with high affinity. We asked whether T cells would be able to present soluble antigens that bind to their own surface molecules. Here we show that such antigens can be effectively processed and presented by both CD4+- and CD8+-bearing human T cells. This indicates that T cells are fully capable of processing and displaying antigens and are mainly limited in antigen presentation by their inefficiency at antigen capture. 相似文献
85.
Interleukin 7 receptor alpha chain (IL7R) shows allelic and functional association with multiple sclerosis 总被引:17,自引:0,他引:17
Gregory SG Schmidt S Seth P Oksenberg JR Hart J Prokop A Caillier SJ Ban M Goris A Barcellos LF Lincoln R McCauley JL Sawcer SJ Compston DA Dubois B Hauser SL Garcia-Blanco MA Pericak-Vance MA Haines JL;Multiple Sclerosis Genetics Group 《Nature genetics》2007,39(9):1083-1091
Multiple sclerosis is a demyelinating neurodegenerative disease with a strong genetic component. Previous genetic risk studies have failed to identify consistently linked regions or genes outside of the major histocompatibility complex on chromosome 6p. We describe allelic association of a polymorphism in the gene encoding the interleukin 7 receptor alpha chain (IL7R) as a significant risk factor for multiple sclerosis in four independent family-based or case-control data sets (overall P = 2.9 x 10(-7)). Further, the likely causal SNP, rs6897932, located within the alternatively spliced exon 6 of IL7R, has a functional effect on gene expression. The SNP influences the amount of soluble and membrane-bound isoforms of the protein by putatively disrupting an exonic splicing silencer. 相似文献
86.
It has become increasingly difficult to keep pace with the amount of information being generated about how to evaluate organizations. If it were not enough that the situation is made difficult by the sheer mass of material on evaluation, clarity is further hindered by many of the publications on the subject failing to make explicit the principles and assumptions upon which they are based. This was the situation confronting the authors when they began a national project with the National Association of Councils for Voluntary Service on the evaluation of the performance of Councils for Voluntary Service. In an attempt to bring some order to the field, this paper adopts a systems and contingency approach to elucidate the nature and practical usefulness of the different methods of evaluation. It first seeks, using some tools of Checkland's soft systems methodology, to present a systematic analysis of the subject of evaluation. Then, in the light of the analysis, an attempt is made to formulate a simple classification of approaches to evaluation which serves to match the different forms of evaluation to the contexts in which they are most appropriate for use. 相似文献
87.
88.
中国乡村的城镇化进程体现在货物、资金、人员和信息的流动 ,这些流动已经在过去的十几年甚至更长时间的中国产生了极大的影响。然而 ,所有这些变化都没有离开成千上万的中国农民的迁徙的机动性。 相似文献
89.
de Bakker PI McVean G Sabeti PC Miretti MM Green T Marchini J Ke X Monsuur AJ Whittaker P Delgado M Morrison J Richardson A Walsh EC Gao X Galver L Hart J Hafler DA Pericak-Vance M Todd JA Daly MJ Trowsdale J Wijmenga C Vyse TJ Beck S Murray SS Carrington M Gregory S Deloukas P Rioux JD 《Nature genetics》2006,38(10):1166-1172
The proteins encoded by the classical HLA class I and class II genes in the major histocompatibility complex (MHC) are highly polymorphic and are essential in self versus non-self immune recognition. HLA variation is a crucial determinant of transplant rejection and susceptibility to a large number of infectious and autoimmune diseases. Yet identification of causal variants is problematic owing to linkage disequilibrium that extends across multiple HLA and non-HLA genes in the MHC. We therefore set out to characterize the linkage disequilibrium patterns between the highly polymorphic HLA genes and background variation by typing the classical HLA genes and >7,500 common SNPs and deletion-insertion polymorphisms across four population samples. The analysis provides informative tag SNPs that capture much of the common variation in the MHC region and that could be used in disease association studies, and it provides new insight into the evolutionary dynamics and ancestral origins of the HLA loci and their haplotypes. 相似文献
90.
Chendrimada TP Gregory RI Kumaraswamy E Norman J Cooch N Nishikura K Shiekhattar R 《Nature》2005,436(7051):740-744