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Jonathan Larkin Anne Bost John I Glass Seng-Lai Tan 《Journal of interferon & cytokine research》2006,26(12):854-865
Hepatitis C virus (HCV)-specific impairments in host immunity have been described at multiple levels of the innate and adaptive response, which may lead to viral persistence in the majority of infections. Understanding of HCV-associated immune defects could lead to novel therapeutic advances. Natural killer (NK) cells, the major effector cells of the innate immune system, are functionally impaired in chronic HCV infection. It has been suggested that this phenotype is a result of virus-specific defects in antigen-presenting cells (APCs) that regulate NK cell activity, as normal NK function is restored when they are stimulated ex vivo. In this study, we used human NK cell cytotoxicity assays to evaluate the activation-induced effects of NK cells on the HCV replicon-containing hepatic cells. We found that cytokine-activated NK cells were capable of inducing an HCV-associated, perforin/granzyme-dependent lysis of human hepatoma cells and that this required direct cellular contact and was independent of MHC class I expression levels. In contrast, on removal of cytokine stimulation, NK cells failed to exert any direct cytolytic effect on replicon targets. These findings suggest an important underlying mechanism by which NK cells control HCV infection and, with appropriate understanding of HCV-associated immune defects, could lead to novel therapeutic advances. 相似文献
3.
A 60-year-old man developed hemiballismus due to an intracranial hemorrhage involving the subthalamic nucleus 8 weeks after orthotopic liver transplantation. The hemorrhage was thought to be due to alterations in cerebral blood flow following a period of hypotensive shock due to sepsis, in the presence of anticoagulant therapy and thrombocytopenia. This represents a rare neurologic complication of liver transplantation. 相似文献
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Celiac Disease 总被引:1,自引:0,他引:1
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G Gaitanis K Nomikos E Vava EC Alexopoulos ID Bassukas 《Journal of the European Academy of Dermatology and Venereology》2009,23(12):1427-1431
Background/aim Theoretical considerations support the combination of cryosurgery and topical imiquimod to treat basal cell carcinomas (BCC). The aim of the present study was to test the feasibility and efficacy of 'cryosurgery during continued imiquimod application' ('immunocryosurgery') to treat 'high-risk-for-recurrence' BCCs.
Methods Thirteen patients with 21 biopsy-proven tumours (4 of 21 relapses after prior surgery) were included. After 2–5 weeks (median, 3) of daily 5% imiquimod cream application, the tumours were treated by liquid N2 cryosurgery (spray, two cycles, 10–20 s) and imiquimod was continued for additional 2–12 weeks (median, 4). The outcome after at least 18 months of follow-up (18–24 months) is currently reported.
Results Nineteen of 21 tumours responded promptly to immunocryosurgery; two tumours required additional treatment cycles to clear. Thus, the clinical clearance rate was 100%. Only 1 of 21(5%) tumour relapsed after at least 18 months of follow-up (cumulative efficacy: 95%).
Conclusions 'Immunocryosurgery' is a promising non-surgical combination modality to treat 'high-risk-for-recurrence BCCs'. Initial evidence is suggestive of an at least additive effect of the two combined modalities. Further studies comparing immunocryosurgery directly with cryosurgery and imiquimod monotherapies will confirm the reported results. 相似文献
Methods Thirteen patients with 21 biopsy-proven tumours (4 of 21 relapses after prior surgery) were included. After 2–5 weeks (median, 3) of daily 5% imiquimod cream application, the tumours were treated by liquid N
Results Nineteen of 21 tumours responded promptly to immunocryosurgery; two tumours required additional treatment cycles to clear. Thus, the clinical clearance rate was 100%. Only 1 of 21(5%) tumour relapsed after at least 18 months of follow-up (cumulative efficacy: 95%).
Conclusions 'Immunocryosurgery' is a promising non-surgical combination modality to treat 'high-risk-for-recurrence BCCs'. Initial evidence is suggestive of an at least additive effect of the two combined modalities. Further studies comparing immunocryosurgery directly with cryosurgery and imiquimod monotherapies will confirm the reported results. 相似文献
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Quantitative assessment of immunocytochemical staining for gonadotropin-releasing hormone (GnRH) was undertaken to determine the effects of an intracranial implant of melatonin on the GnRH neuronal system in the male white-footed mouse (Peromyscus leucopus). Melatonin-containing pellets stereotaxically placed in the anterior hypothalamic area (AH) caused a 60% reduction in testes weight relative to control mice with melatonin-free pellets in the AH (p less than 0.01). Subcutaneous melatonin-containing implants had little effect on reproductive state (p less than 0.8). Melatonin pellets in the AH increased significantly both the optical density (OD) for immunostaining of cell bodies in the medial preoptic area and AH (p less than 0.04), and the percentage of area covered by GnRH fibers and beads in the median eminence (p less than 0.01). The melatonin-induced increase in OD of the GnRH cell bodies was independent of the distance of the cells from the melatonin implant, and there was little apparent effect of melatonin on the size and morphology of the GnRH cell bodies, or the trajectories of their fiber pathways. These results support the hypothesis that the antigonadal action of melatonin in the brain involves suppression of the release, rather than the synthesis of GnRH. Also, this effect may not be mediated via a direct action of melatonin on GnRH neurons. The finding that the brain site and time course for melatonin's antigonadal action in male. P. leucopus is similar to that found previously in the female is evidence that melatonin may induce gonadal regression, in part, by helping to suppress the tonic secretion of gonadotropins. 相似文献
10.
Julie A Clennon Aniset Kamanga Mulenga Musapa Clive Shiff Gregory E Glass 《International journal of health geographics》2010,9(1):58