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91.
Hotter GS Wards BJ Mouat P Besra GS Gomes J Singh M Bassett S Kawakami P Wheeler PR de Lisle GW Collins DM 《Journal of bacteriology》2005,187(7):2267-2277
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Voluntary accreditation in the United Kingdom is being used by health care providers to improve and market their services and by commissioners to define and monitor service contracts. In a three year pilot scheme in the south west of England, 43 out of 57 eligible community hospitals volunteered to be surveyed; 37 of them were ultimately accredited for up to two years by the hospital accreditation programme. The main causes for non-accreditation related to safety, clinical records, and medical organisation. Follow up visits in 10 hospitals showed that, overall, 69% of recommendations were implemented. An independent survey of participating hospitals showed the perceived benefits to include team building, review of operational policies, improvement of data systems, and the generation of local prestige. Purchasers are increasingly influenced by accreditation status but are mostly unwilling to finance the process directly. None the less, the concept may become an important factor moderating the quality of service in the new NHS. 相似文献
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A L Back W W Kwok M Adam S J Collins D D Hickstein 《Biochemical and biophysical research communications》1990,171(2):787-795
Children with leukocyte adherence deficiency (LAD) exhibit heterogeneous defects in the leukocyte integrin CD18 subunit that prevent surface expression of functional CD11/CD18 leukocyte integrin adherence complexes. We used a retroviral vector, designated LCD18SN, to transfer the CD18 cDNA into K562 human myeloid leukemia cells and into EBV B-cells from a child with LAD. Transfer of the LCD18SN retroviral construct, which expresses the CD18 cDNA from the Moloney Murine leukemia virus (MoMLV) long terminal repeat (LTR), into K562 cells resulted in relatively high levels of CD18 mRNA and intracellular protein. Retroviral-mediated gene transfer of CD18 into LAD EBV B-cells resulted in low, but readily measurable, levels of surface expression of the CD11a/CD18 complex in these previously deficient lymphocytes. The reconstitution of surface expression of the CD11a/CD18 complex by gene transfer of the CD18 cDNA into LAD EBV B-cells indicates that this syndrome represents a candidate disorder for gene therapy. 相似文献
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Fowell AJ Collins JE Duncombe DR Pickering JA Rosenberg WM Benyon RC 《Biochemical and biophysical research communications》2011,(2):449-282
Myofibroblastic, activated hepatic stellate cells (HSC) play a pivotal role in the development of liver fibrosis through the secretion of fibrillar collagens and the tissue inhibitors of metalloproteinase (TIMP)-1 and -2. TIMPs are believed to promote hepatic fibrosis by inhibiting both matrix degradation and apoptosis of HSC. In other cell types, there is evidence that TIMP-1 has effects on proliferation, however the role of TIMPs in the regulation of HSC proliferation remains unexplored. Therefore, we have used short interfering RNA (siRNA) to investigate the effects of autocrine TIMP-1 and -2 on HSC proliferation. TIMP-1 and -2 siRNA were highly effective, producing peak target protein knockdown compared to negative control siRNA of 92% and 63%, respectively. Specific silencing of TIMP-1, using siRNA, significantly reduced HSC proliferation. TIMP-1 was localised in part to the HSC nucleus and TIMP-1 siRNA resulted in loss of both cytoplasmic and nuclear TIMP-1. Attenuated proliferation was associated with reduced Akt phosphorylation and was partially rescued by addition of recombinant TIMP-1. We have revealed a novel autocrine mitogenic effect of TIMP-1 on HSC, which may involve Akt-dependent and specific nuclear mechanisms of action. We suggest that TIMP-1 might promote liver fibrosis by means other than its previously described anti-apoptotic effect on HSC. Moreover, these findings, together with our previous reports and the emerging data from in vivo studies of TIMP inhibition, provide strong evidence that TIMP-1 is mechanistically central to liver fibrosis and an important potential therapeutic target. 相似文献
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We analyse a model of mate choice when males differ in reproductive quality and provide care for their offspring. Females choose males on the basis of the success they will obtain from breeding with them and a male chooses his care time on the basis of his quality so as to maximise his long-term rate of reproductive success. We use this model to establish whether high-quality males should devote a longer period of care to their broods than low-quality males and whether females obtain greater reproductive success from mating with higher quality males. We give sufficient conditions for optimal care times to decrease with increasing male quality. When care times decrease, this does not necessarily mean that high-quality males are less valuable to the female because quality may more than compensate for the lack of care. We give a necessary and sufficient condition for high-quality males to be less valuable mates, and hence for females to prefer low-quality males. Females can prefer low-quality males if offspring produced and cared for by high-quality males do well even if care is short, and do not significantly benefit from additional care, while offspring produced and cared for by low-quality males do well only if they receive a long period of care. 相似文献