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101.
Assembly and function of the two ABC transporter proteins encoded in the human major histocompatibility complex. 总被引:30,自引:0,他引:30
A Kelly S H Powis L A Kerr I Mockridge T Elliott J Bastin B Uchanska-Ziegler A Ziegler J Trowsdale A Townsend 《Nature》1992,355(6361):641-644
Presentation of cytoplasmic antigens to class I-restricted cytotoxic T cells implied the existence of a specialized peptide transporter. For most class I heavy chains, association with peptides of the appropriate length is required for stable assembly with beta 2-microglobulin. Mutant cells RMA-S and .174/T2 neither assemble stable class I molecules nor present intracellular antigens, and we have suggested that they have lost a function required for the transport of short peptides from the cytosol to the endoplasmic reticulum. The genetic defect in .174 has been localized to a large deletion in the class II region of the major histocompatibility complex, within which two genes (RING4 and RING11) have been identified that code for 'ABC' (ATP-binding cassette) transporters. We report here that the protein products of these two genes assemble to form a complex. Defects in either protein result in the formation of unstable class I molecules and loss of presentation of intracellular antigens. The molecular defect in a new mutant, BM36.1, is shown to be in the ATP-binding domain of the RING11/PSF2 protein. This is in contrast to the mutant .134, which lacks the RING4/PSF1 protein. 相似文献
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Planavsky NJ McGoldrick P Scott CT Li C Reinhard CT Kelly AE Chu X Bekker A Love GD Lyons TW 《Nature》2011,477(7365):448-451
The chemical composition of the ocean changed markedly with the oxidation of the Earth's surface, and this process has profoundly influenced the evolutionary and ecological history of life. The early Earth was characterized by a reducing ocean-atmosphere system, whereas the Phanerozoic eon (less than 542 million years ago) is known for a stable and oxygenated biosphere conducive to the radiation of animals. The redox characteristics of surface environments during Earth's middle age (1.8-1 billion years ago) are less well known, but it is generally assumed that the mid-Proterozoic was home to a globally sulphidic (euxinic) deep ocean. Here we present iron data from a suite of mid-Proterozoic marine mudstones. Contrary to the popular model, our results indicate that ferruginous (anoxic and Fe(2+)-rich) conditions were both spatially and temporally extensive across diverse palaeogeographic settings in the mid-Proterozoic ocean, inviting new models for the temporal distribution of iron formations and the availability of bioessential trace elements during a critical window for eukaryotic evolution. 相似文献
104.
Yokoyama S Woods SL Boyle GM Aoude LG MacGregor S Zismann V Gartside M Cust AE Haq R Harland M Taylor JC Duffy DL Holohan K Dutton-Regester K Palmer JM Bonazzi V Stark MS Symmons J Law MH Schmidt C Lanagan C O'Connor L Holland EA Schmid H Maskiell JA Jetann J Ferguson M Jenkins MA Kefford RF Giles GG Armstrong BK Aitken JF Hopper JL Whiteman DC Pharoah PD Easton DF Dunning AM Newton-Bishop JA Montgomery GW Martin NG Mann GJ Bishop DT Tsao H Trent JM Fisher DE Hayward NK Brown KM 《Nature》2011,480(7375):99-103
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C Auclair L Ferland L Cusan P A Kelly F Labrie G Azadian-Boulanger J P Raynaud 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(18):1305-1307
A single injection of LHRH to the adult male rat, as of its analog [D-Ala6, des-Gly-NH102] LHRH ethylamide, resulted in a marked decrease in LH receptors in the tests. Plasma testosterone level and the weight of the seminal vesicles and prostate were also decreased after treatment. These data demonstrate that LHRH can decrease the sensitivity of LH receptors and testicular function in the rat. 相似文献
108.
S. S. Kelly 《Cellular and molecular life sciences : CMLS》1978,34(2):200-201
Summary A quantitative restriction of food intake for 7 days reduced the amplitude of spontaneous miniature endplate potentials by about 1/3 in rats aged 30 days but not in rats aged 110 days.I would like to thank Dr D. V. Roberts for encouragement and advice and the Medical Research Council and the Muscular Dystrophy Group of Great Britain for financial support. 相似文献
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