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蔡俊超 《中华移植杂志(电子版)》2010,(4)
随着器官移植体液免疫理论的发展与抗体检测技术的进步,抗体介导的排斥反应(AMR)已逐渐被认识和引起关注。其治疗难度大、逆转率较低,已成为导致移植物失功的重要原因。本文较为系统地介绍了AMR的免疫机制、诊断与防治进展,以及供者特异性抗体的检测技术和临床意义,从而提出供者特异性抗体是引起移植物排斥反应特别是慢性排斥反应的主要原因,移植受者需常规监测抗体以利及时干预和治疗。 相似文献
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Although the intercellular adhesion molecule-1 (ICAM-1) is constitutively expressed at a low level on a subpopulation of hematopoietic cells, on vascular endothelium, on fibroblasts, and on certain epithelial cells, it is dramatically increased at sites of inflammation. Interferon-gamma (IFN-gamma) and phorbol myristate acetate (PMA) are known to increase the expression of ICAM-1 on many cell types. Because both human and murine ICAM-1 mRNAs contain putative destabilizing AUUUA sequences in their 3' untranslated regions (UTRs), we examined the role of mRNA stability in the regulation of ICAM-1 gene expression. The treatment of the murine monocytic cell line P388D1, which constitutively expresses ICAM-1 mRNA at a low level, with IFN- gamma or PMA rapidly enhanced the level of ICAM-1 mRNA and dramatically prolonged its half-life. To determine whether the putative destabilizing sequences are responsible for this effect of IFN-gamma and PMA, fibroblast L cells were transfected with either the full- length ICAM-1 cDNA or a truncated form (ICAM-1 delta 3) lacking the putative destabilizing AUUUA sequences. Although ICAM-1 delta 3 mRNA was more stable than the full-length ICAM-1 mRNA, IFN-gamma treatment induced the accumulation of both mRNA species and prolongation of their half-lives. The transplantation of the ICAM-1 delta 3' UTR into a stable ICAM-2 mRNA rendered it unstable, and it was unresponsive to IFN- gamma. Therefore, the treatment with IFN-gamma stabilizes the otherwise labile ICAM-1 mRNA, but the IFN-gamma-responsive sequence may at least in part reside within the protein coding region. PMA also upregulated ICAM-1 gene expression by mRNA stabilization. However, unlike IFN- gamma, PMA treatment only increased the level of the full-length, but not of the truncated, ICAM-1 mRNA. This shows that the PMA-responsive element is located within the 3'UTR. Furthermore, the effect of PMA on ICAM-1 delta 3 mRNA was recovered by ligating multiple AUUUA sequences derived from a heterologous gene fragment. The stability of this chimeric mRNA and the full-length ICAM-1 mRNA was markedly increased by PMA treatment, indicating that the AUUUA multimers in the 3'UTR are important in the PMA-induced upregulation of ICAM-1 mRNA. 相似文献
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Biologic basis for interleukin-1 in disease 总被引:164,自引:6,他引:164
To understand the role of the proinflammatory cytokine interleukin-1 (IL-1) in disease, investigators have studied how production of the different members of the IL-1 family is controlled, the various biologic activities of IL-1, the distinct and various functions of the IL-1 receptor (IL-1R) family, and the complexity of intracellular signaling. Mice deficient in IL-1Beta, IL-1Beta converting enzyme, and IL-1R type I have also been studied. Humans have been injected with IL- 1 (either IL-1alpha or IL-1beta) for enhancing bone marrow recovery and for cancer treatment. The IL-1-specific receptor antagonist (IL-1Ra) has also been tested in clinical trials. The topics discussed in this review include production and activities of IL-1 and IL-1Ra molecules, the effects of IL-1 on gene expression, functions of cell-bound and soluble IL-1 receptors, the importance of the IL-1R accessory protein, newly discovered signal transduction pathways, naturally occurring cytokines limiting IL-1 production or activity, the effects of blocking cyclooxygenase and nitric oxide, and the outcomes of IL-1 and IL-1 Ra in human trials. Special attention is paid to IL-1beta converting enzyme and programmed cell death. The roles of IL-1 in hematopoiesis, leukemia, atherosclerosis, and growth of solid tumors are also discussed. This is a lengthy review, with 586 citations chosen to illustrate specific areas of interest rather than a compendium of references. At the end of each section, a short commentary summarizes what the author considers established or controversial topics linking the biology of IL-1 to mechanisms of disease. 相似文献
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Erythropoietic activity is known to be closely associated with marrow iron uptake. A modification of the standard measure of plasma iron turnover has been developed in which erythron transferrin uptake (ETU) rather than iron uptake has been calculated. The ETU has the advantage of providing a parameter of erythroid marrow activity independent of change produced by plasma iron and transferrin saturation. Measurements in 80 patients with anemia were compared to the normal value of 60 +/- 12 mumol/L whole blood/d. The mean ETU for ten patients with severe aplastic anemia and for six patients with pure red-cell aplasia were 12 +/- 8 and 12 +/- 11 mumol/L whole blood/d, respectively. In ten transfusion-dependent patients with renal failure under dialysis therapy, the mean value was 35 +/- 11, while ten other dialyzed patients who were transfusion independent had a mean ETU of 73 +/- 21 mumol/L whole blood/d. Sixteen patients with hemolytic anemia had an average ETU of 400 +/- 130, while 28 patients with ineffective erythropoiesis had a mean value of 474 +/- 147 mumol/L whole blood/d. While patients with hypoproliferative anemia showed no relation between the severity of anemia and ETU, those with hyperproliferative erythroid marrow showed increasing values as the anemia became more severe. Sequential measurements in patients with aplastic anemia under treatment and in thalassemic patients under transfusion therapy showed the value of this measurement in monitoring the effects of treatment on erythroid marrow activity. It is concluded that the measurement of ETU provides a more direct ferrokinetic evaluation of erythroid activity in anemic states. 相似文献
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The role of defective fibrinolysis caused by elevated activity of plasminogen activator inhibitor-1 (PAI-1) in promoting fibrin deposition in vivo has not been well established. The present study compared the efficacy of thrombin or ancrod, a venom-derived enzyme that clots fibrinogen, to induce fibrin formation in rabbits with elevated PAI-1 levels. One set of male New Zealand rabbits received intravenous endotoxin to increase endogenous PAI-1 activity followed by a 1-hour infusion of ancrod or thrombin; another set of normal rabbits received intravenous human recombinant PAI-1 (rPAI-1) during an infusion of ancrod or thrombin. Thirty minutes after the end of the infusion, renal fibrin deposition was assessed by histopathology. Animals receiving endotoxin, rPAI-1, ancrod, or thrombin alone did not develop renal thrombi. All endotoxin-treated rabbits developed fibrin deposition when infused with ancrod (n = 4) or thrombin (n = 6). Fibrin deposition occurred in 7 of 7 rabbits receiving both rPAI-1 and ancrod and in only 1 of 6 receiving rPAI-1 and thrombin (P < .01). In vitro, thrombin but not ancrod was inactivated by normal rabbit plasma and by purified antithrombin III or thrombomodulin. The data indicate that elevated levels of PAI-1 promote fibrin deposition in rabbits infused with ancrod but not with thrombin. In endotoxin-treated rabbits, fibrin deposition that occurs with thrombin infusion may be caused by decreased inhibition of procoagulant activity and not increased PAI-1 activity. 相似文献
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Identification of T lymphocytes in human mixed hemopoietic colonies 总被引:11,自引:0,他引:11
The addition of a T-cell growth-promoting medium (PHA-TCM) to culture conditions that support growth of multi-lineage hemopoietic colonies enhances the proliferation of cells with lymphoid morphology within these colonies. These cells were identified as T lymphocytes by their ability to form rosettes with SRBC and their reaction with monoclonal antibodies (OKT3, OKT4) directed against T-cell-specific surface components. They continue to proliferate extensively under the influence of PHA-TCM after transfer of mixed colonies into liquid suspension culture. Supportive evidence for a common progenitor of myeloid and lymphoid cells within single mixed colonies is provided by Y-chromatin body analysis of E-rosette positive and negative cells in colonies grown in cocultures of male and female bone marrow cells. 相似文献