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排序方式: 共有69条查询结果,搜索用时 15 毫秒
1.
F.W. Gibbs M.Sc. Ph.D. 《Annals of science》2013,70(2):122-151
2.
Shachi P. Patel Suzanne J. Randle Sarah Gibbs Anne Cooke Heike Laman 《Cellular and molecular life sciences : CMLS》2017,74(8):1553-1566
G1 phase cell cycle proteins, such as cyclin-dependent kinase 6 (Cdk6) and its activating partners, the D-type cyclins, are important regulators of T-cell development and function. An F-box protein, called F-box only protein 7 (Fbxo7), acts as a cell cycle regulator by enhancing cyclin D-Cdk6 complex formation and stabilising levels of p27, a cyclin-dependent kinase inhibitor. We generated a murine model of reduced Fbxo7 expression to test its physiological role in multiple tissues and found that these mice displayed a pronounced thymic hypoplasia. Further analysis revealed that Fbxo7 differentially affected proliferation and apoptosis of thymocytes at various stages of differentiation in the thymus and also mature T-cell function and proliferation in the periphery. Paradoxically, Fbxo7-deficient immature thymocytes failed to undergo expansion in the thymus due to a lack of Cdk6 activity, while mature T cells showed enhanced proliferative capacity upon T-cell receptor engagement due to reduced p27 levels. Our studies reveal differential cell cycle regulation by Fbxo7 at different stages in T-cell development. 相似文献
3.
Genome-wide detection and characterization of positive selection in human populations 总被引:3,自引:0,他引:3
Sabeti PC Varilly P Fry B Lohmueller J Hostetter E Cotsapas C Xie X Byrne EH McCarroll SA Gaudet R Schaffner SF Lander ES;International HapMap Consortium Frazer KA Ballinger DG Cox DR Hinds DA Stuve LL Gibbs RA Belmont JW Boudreau A Hardenbol P Leal SM Pasternak S Wheeler DA Willis TD Yu F Yang H Zeng C Gao Y Hu H Hu W Li C Lin W Liu S Pan H Tang X Wang J Wang W Yu J Zhang B Zhang Q Zhao H Zhao H Zhou J Gabriel SB Barry R Blumenstiel B Camargo A Defelice M Faggart M Goyette M Gupta S Moore J 《Nature》2007,449(7164):913-918
With the advent of dense maps of human genetic variation, it is now possible to detect positive natural selection across the human genome. Here we report an analysis of over 3 million polymorphisms from the International HapMap Project Phase 2 (HapMap2). We used 'long-range haplotype' methods, which were developed to identify alleles segregating in a population that have undergone recent selection, and we also developed new methods that are based on cross-population comparisons to discover alleles that have swept to near-fixation within a population. The analysis reveals more than 300 strong candidate regions. Focusing on the strongest 22 regions, we develop a heuristic for scrutinizing these regions to identify candidate targets of selection. In a complementary analysis, we identify 26 non-synonymous, coding, single nucleotide polymorphisms showing regional evidence of positive selection. Examination of these candidates highlights three cases in which two genes in a common biological process have apparently undergone positive selection in the same population:LARGE and DMD, both related to infection by the Lassa virus, in West Africa;SLC24A5 and SLC45A2, both involved in skin pigmentation, in Europe; and EDAR and EDA2R, both involved in development of hair follicles, in Asia. 相似文献
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5.
Twigger SN Pruitt KD Fernández-Suárez XM Karolchik D Worley KC Maglott DR Brown G Weinstock G Gibbs RA Kent J Birney E Jacob HJ 《Nature genetics》2008,40(5):523-527
It has been four years since the original publication of the draft sequence of the rat genome. Five groups are now working together to assemble, annotate and release an updated version of the rat genome. As the prevailing model for physiology, complex disease and pharmacological studies, there is an acute need for the rat's genomic resources to keep pace with the rat's prominence in the laboratory. In this commentary, we describe the current status of the rat genome sequence and the plans for its impending 'upgrade'. We then cover the key online resources providing access to the rat genome, including the new SNP views at Ensembl, the RefSeq and Genes databases at the US National Center for Biotechnology Information, Genome Browser at the University of California Santa Cruz and the disease portals for cardiovascular disease and obesity at the Rat Genome Database. 相似文献
6.
Montgomery KT Lee E Miller A Lau S Shim C Decker J Chiu D Emerling S Sekhon M Kim R Lenz J Han J Ioshikhes I Renault B Marondel I Yoon SJ Song K Murty VV Scherer S Yonescu R Kirsch IR Ried T McPherson J Gibbs R Kucherlapati R 《Nature》2001,409(6822):945-946
Our sequence-tagged site-content map of chromosome 12 is now integrated with the whole-genome fingerprinting effort. It provides accurate and nearly complete bacterial clone coverage of chromosome 12. We propose that this integrated mapping protocol serves as a model for constructing physical maps for entire genomes. 相似文献
7.
Rapid degradation of a large fraction of newly synthesized proteins by proteasomes 总被引:47,自引:0,他引:47
MHC class I molecules function to present peptides eight to ten residues long to the immune system. These peptides originate primarily from a cytosolic pool of proteins through the actions of proteasomes, and are transported into the endoplasmic reticulum, where they assemble with nascent class I molecules. Most peptides are generated from proteins that are apparently metabolically stable. To explain this, we previously proposed that peptides arise from proteasomal degradation of defective ribosomal products (DRiPs). DRiPs are polypeptides that never attain native structure owing to errors in translation or post-translational processes necessary for proper protein folding. Here we show, first, that DRiPs constitute upwards of 30% of newly synthesized proteins as determined in a variety of cell types; second, that at least some DRiPs represent ubiquitinated proteins; and last, that ubiquitinated DRiPs are formed from human immunodeficiency virus Gag polyprotein, a long-lived viral protein that serves as a source of antigenic peptides. 相似文献
8.
Zusammenfassung Es wird eine Methode zur Extraktion und Reinigung von Myosin und Actomyosin aus Rindermuskelgewebe mittels Ammoniumsulfat beschrieben. Aus 1 kg Muskelfleisch wurden 15–20 g Myosin und 10–20 g Actomyosin gewonnen. 相似文献
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Bombesin (BBS) is a tetradecapeptide originally isolated from amphibian skin1. BBS-like immunoactivity is widely distributed in mammalian gut2-5, and plasma levels have been shown to rise sharply following feeding (ref. 6 and V. Erspamer, personal communication). The physiological actions of BBS are unknown. We have previously shown that the classic gut hormone cholecystokinin (CCK) is a powerful and specific suppressor of food intake7-9. Although CCK and BBS lack common amino acid sequences, they have certain common actions on gut viscera10,11. We have now shown that BBS also suppresses food intake, and we compare its action with that of CCK. 相似文献