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61.
Reciprocal translocations in breast tumor cell lines: cloning of a t(3;20) that targets the FHIT gene 总被引:1,自引:0,他引:1
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de Tychey C Spitz E Briançon S Lighezzolo J Girvan F Rosati A Thockler A Vincent S 《Journal of affective disorders》2005,85(3):323-326
BACKGROUND: The assessment of perinatal depressions and coping style. Methods: With depression scales (EPDS, GHQ.12) and Carver's BriefCope, the authors compared the prevalence rates of pre and postnatal depression in a cohort of 277 French women. RESULTS: Their work revealed very high levels of prenatal depression (almost 20%) and less important but nonetheless sizeable rates (11%) of postnatal depression, making such perinatal depressions a major public health concern. The coping styles proposed in Carver's public health BriefCope questionnaire make it possible to significantly differentiate during these two periods between depressive women and their non-depressed counterparts. CONCLUSIONS: This enables us to underline factors of risk and protection suggesting the importance of setting up compensatory and preventive systems and evaluating their pertinence in the framework of future research. 相似文献
64.
Ferrer I Kapfhammer JP Hindelang C Kemp S Troffer-Charlier N Broccoli V Callyzot N Mooyer P Selhorst J Vreken P Wanders RJ Mandel JL Pujol A 《Human molecular genetics》2005,14(23):3565-3577
ATP-binding cassette (ABC) transporters facilitate unidirectional translocation of chemically diverse substances, ranging from peptides to lipids, across cell or organelle membranes. In peroxisomes, a subfamily of four ABC transporters (ABCD1 to ABCD4) has been related to fatty acid transport, because patients with mutations in ABCD1 (ALD gene) suffer from X-linked adrenoleukodystrophy (X-ALD), a disease characterized by an accumulation of very-long-chain fatty acids (VLCFAs). Inactivation in the mouse of the abcd1 gene leads to a late-onset neurodegenerative condition, comparable to the late-onset form of X-ALD [Pujol, A., Hindelang, C., Callizot, N., Bartsch, U., Schachner, M. and Mandel, J.L. (2002) Late onset neurological phenotype of the X-ALD gene inactivation in mice: a mouse model for adrenomyeloneuropathy. Hum. Mol. Genet., 11, 499-505.]. In the present work, we have generated and characterized a mouse deficient for abcd2, the closest paralog to abcd1. The main pathological feature in abcd2-/- mice is a late-onset cerebellar and sensory ataxia, with loss of cerebellar Purkinje cells and dorsal root ganglia cell degeneration, correlating with accumulation of VLCFAs in the latter cellular population. Axonal degeneration was present in dorsal and ventral columns in spinal cord. We have identified mitochondrial, Golgi and endoplasmic reticulum damage as the underlying pathological mechanism, thus providing evidence of a disturbed organelle cross-talk, which may be at the origin of the pathological cascade. 相似文献
65.
The oligomeric structure and the fusion activity of lyssavirus glycoprotein (G) was studied by comparing G from Mokola virus (GMok) and rabies virus (PV strain) (GPV), which are highly divergent lyssaviruses. G expressed at the surface of BSR cells upon either plasmid transfection or virus infection are shown to be mainly trimeric after cross-linking experiments. However, solubilization by a detergent (CHAPS) and analysis in sucrose sedimentation gradient evidenced that GMok trimer is less stable than GPV trimer. A chimeric glycoprotein (G Mok-PV) associating the N-terminal half of GMok to the C-terminal half part of GPV formed trimers with an intermediate stability, indicating that the G C-terminal domain is essential in trimer stability. A cell to cell fusion assay revealed that GMok (and not G Mok-PV) was able to induce fusion at a higher pH (0.5 pH unit) than GPV. Such differences in the oligomeric structure stability and in the fusion activity of lyssavirus glycoproteins may partly account for the previously reported differences of their immunogenic and pathogenic properties. 相似文献
66.
The Ysc-Yop type III secretion (TTS) system allows extracellular Yersinia bacteria, adhering to eukaryotic target cells, to inject Yop effector proteins in the cytosol of these cells. The secretion apparatus, called the injectisome, ends up with a needle-like structure made of YscF. YopN, one of the proteins secreted by the injectisome is thought to act as a plug. YopB, YopD and LcrV, three other proteins secreted by the injectisome and called 'translocators' form a pore allowing translocation of the Yop effectors across the target cell plasma membrane. Here, we tested the role of LcrV, YscF and YopN in the formation of this pore in macrophages by monitoring the release of the low-molecular-weight fluorescent dye BCECF (2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein, acetoxymethyl ester, 623Da) and of the high-molecular-weight lactate dehydrogenase (LDH, 135 kDa). BCECF is released through the translocation pore itself provided no Yop effector is trafficking through the channel. In contrast, LDH is released by the osmotic lysis of the target cell that occurs after pore formation. This release is reduced by the GAP activity of YopE. In order to study the role of LcrV, one has to circumvent the regulatory effect of LcrV on the synthesis of YopB and YopD. We observed here that this regulatory role of LcrV is lost in a yopQ mutant and hence we studied the role of LcrV in a yopQ mutant background. A lcrV, yopQ double mutant was deficient in pore formation while able to produce YopB and YopD. Pore formation was restored by the introduction of lcrV(+) but not yopQ(+) confirming that LcrV itself is directly required for pore formation. Bacteria secreting only YopB, YopD and LcrV could form pores, showing that YopB, YopD and LcrV are sufficient for pore formation provided they are secreted by the same bacterium. LcrV is not involved in secretion of YopB and YopD as suggested previously. Bacteria producing normal Ysc injectisomes, including the YscF needle but no translocators did not form pores, indicating that the needle is not sufficient by itself for pore formation, as was also suggested. yopN mutant bacteria formed needles and released BCECF even if they secreted the effectors. This observation suggests that many translocation pores are not filled in the absence of YopN and thus that YopN might form a link between the needle and the pore, guiding the effectors. 相似文献
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Akeb F Ferrua B Creminon C Roptin C Grassi J Nevers MC Guedj R Garraffo R Duval D 《Journal of immunological methods》2002,263(1-2):1-9
The HIV protease inhibitor ritonavir (Norvir; ABT-578), currently used in combination with nucleoside analogs and other protease inhibitors in anti-HIV therapy, has previously been quantified by an HPLC procedure. Here, we report the first convenient one-step competitive ELISA for measuring plasma and intracellular ritonavir in HIV patients. Anti-ritonavir antibody was raised in rabbits using ritonavir-KLH conjugate as immunogen, and the enzymatic tracer was prepared by coupling the drug to acetylcholine esterase. Samples for analysis were first extracted with methanol. Bound/free separation was achieved in a microtiter plate previously coated with anti rabbit IgG monoclonal antibody. Fifty percent inhibition was observed at 1 ng/ml ritonavir and the method accurately and specifically detected as little as 3-4 ng/ml of plasma ritonavir as well as intracellular drug in the peripheral blood mononuclear cells of patients undergoing ritonavir therapy. Within-run and day to day coefficients of variation were below 10% and the drugs currently used in HIV therapy did not interfere with the test. The ELISA was applied to the measurement of plasma ritonavir and to the determination of the extracellular/intracellular drug level ratios in HIV patients receiving long-term multidrug therapy. 相似文献
70.
Origin and filiation of human plasmacytoid dendritic cells 总被引:8,自引:0,他引:8
Brière F Bendriss-Vermare N Delale T Burg S Corbet C Rissoan MC Chaperot L Plumas J Jacob MC Trinchieri G Bates EE 《Human immunology》2002,63(12):1081-1093
Human plasmacytoid dendritic cells represent a rare population of leukocytes which produce high amounts of type I interferon in response to certain viruses. Although those cells were first described in 1958, there are still unsolved issues related to their origin and function. Recently, a leukemic counterpart of plasmacytoid dendritic cells was identified. Molecular approaches using either normal or leukemic plasmacytoid dendritic cells provide some new insights into the controversial lymphoid origin of those cells. The need for specific markers is still a critical aspect for the identification of plasmacytoid dendritic cells, whatever stage of differentiation, in normal as well as in pathological conditions. Hopefully, novel markers will allow delineation of the relationships between dendritic cells at different stages of differentiation/maturation along the myeloid and lymphoid lineages. 相似文献