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981.
Molecular mechanisms underlying SHP-1 gene expression. 总被引:2,自引:0,他引:2
982.
Alberto Luis Cione 《Geobios》2002,35(3):367
The first record of the knifejaw family Oplegnathidae in the Atlantic Ocean and in South America is reported. It comes from the lowermost beds of the Early Miocene Gaiman Formation at the lower Río Chubut valley, central-eastern Patagonia. The family Oplegnathidae does not occur in the Atlantic today, but it was widespread in comparison to other knifejaw fishes, such as scarids and odacids. Several aquatic vertebrates were extirpated from the southern Atlantic Ocean in the Late Neogene. This record establishes a minimal age (Early Miocene) for the extirpation of the family Oplegnathidae in the Atlantic Ocean. 相似文献
983.
Inhibition of human MDA-MB-231 breast cancer cell invasion by matrix metalloproteinase 3 involves degradation of plasminogen. 总被引:7,自引:0,他引:7
Antonietta R Farina Antonella Tacconelli Lucia Cappabianca Alberto Gulino Andrew R Mackay 《European journal of biochemistry》2002,269(18):4476-4483
Matrix metalloproteinase (MMP)-3 inhibited human MDA-MB-231 breast cancer cell invasion through reconstituted basement membrane in vitro. Inhibition of invasion was dependent upon plasminogen and MMP-3 activation, was impaired by the peptide MMP-3 inhibitor Ac-Arg-Cys-Gly-Val-Pro-Asp-NH2 and was associated with: rapid MMP-3-mediated plasminogen degradation to microplasminogen and angiostatin-like fragments; the removal of single-chain urokinase plasminogen activator from MDA-MB-231 cell membranes; impaired membrane plasminogen association; reduced rate of tissue plasminogen activator (t-PA) and membrane-mediated plasminogen activation; and reduced laminin-degrading capacity. Purified human plasminogen lysine binding site-1 (kringles 1-3) exhibited a similar capacity to inhibit MDA-MB-231 invasion, impair t-PA and cell membrane-mediated plasminogen activation and impair laminin degradation by plasmin. Our data provide evidence that MMP-3 can inhibit breast tumour cell invasion in vitro by a mechanism involving plasminogen degradation to fragments that limit plasminogen activation and the degradation of laminin. This supports the hypothesis that MMP-3, under certain conditions, may protect against tumour invasion, which would help to explain why MMP-3 expression, associated with benign and early stage breast tumours, is frequently lost in advanced stage, aggressive, breast disease. 相似文献
984.
Maren Pink Pierre Sutra Vincenzo BalzaniMargherita Venturi Sebastiano CampagnaScolastica Serroni Alberto Juris 《Inorganica chimica acta》2002,333(1):25-31
The structure and reactivity of the complex [Ru(2,3-Medpp)2Cl2](PF6)2 (2,3-Medpp+=2-[2-(1-methylpyridiniumyl)]-3-(2-pyridyl)pyrazine) was investigated by X-ray diffraction (XRD), 1H NMR, redox, and UV-Vis absorption measurements. X-ray analysis shows that crystals obtained from an acetonitrile-toluene solution contain the trans-Cl2, trans-pyrazine isomeric form, while 1H NMR and redox measurements on the main product of the synthetic workup indicate the presence of the trans-Cl2, cis-pyrazine isomer. In the dark at 70 °C, the complex [Ru(2,3-Medpp)2Cl2]2+ reacts slowly in acetonitrile isomerizing to the cis-[Ru(2,3-Medpp)2(CH3CN)Cl]3+ species. Under ambient light in the presence of excess AgNO3 the cis-[Ru(2,3-Medpp)2(CH3CN)2]4+ species is obtained. 相似文献
985.
986.
987.
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989.
Ana Ruigómez Saga Johansson Mari-Ann Wallander Luis Alberto García Rodríguez 《BMC cardiovascular disorders》2002,2(1):5-7
Objective
To estimate the mortality rate of patients newly diagnosed with chronic atrial fibrillation (AF) and compare it with the one in the general population. To evaluate the role of co-morbidity and other factors on the risk of dying among AF patients. 相似文献990.
Luca M Neri Roberta Bortul Giovanna Tabellini Paola Borgatti Giovanna Baldini Claudio Celeghini Silvano Capitani Alberto M Martelli 《Cellular signalling》2002,14(1):21-29
D-3 phosphorylated inositides are a peculiar class of lipids, synthesized by phosphatidylinositol 3-kinase (PtdIns 3-K), which are also present in the nucleus. In order to clarify a possible role for nuclear D-3 phosphorylated inositides during human erythroid differentiation, we have examined the issue of whether or not, in K562 human erythroleukemia cells, erythropoietin (EPO) may generate nuclear translocation of an active PtdIns 3-K. Immunoprecipitation with an anti-p85 regulatory subunit of PtdIns 3-K, revealed that both the intranuclear amount and the activity of the kinase increased rapidly and transiently in response to EPO. Enzyme translocation was blocked by the specific PtdIns 3-K pharmacological inhibitor, LY294002, which also inhibited erythroid differentiation. In vivo, intranuclear synthesis of phosphatidylinositol (3,4,5) trisphosphate (PtdIns (3,4,5)P(3)) was stimulated by EPO. Almost all PtdIns 3-K that translocated to the nucleus was highly phosphorylated on tyrosine residues of the p85 regulatory subunit. These findings strongly suggest that an important step in the signaling pathways that mediate EPO-induced erythroid differentiation may be represented by the intranuclear translocation of an active PtdIns 3-K. 相似文献