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11.
A method for the quantitation of effector cell binding to anchorage fibroblast monolayers infected with HSV-1 is described. Human peripheral blood polymorphonuclear leukocytes (PMN) as effector cells were labeled with chromium-51. Fetal human lung fibroblasts were grown to confluency in microtiter plates, infected with HSV-1 and loaded with anti-HSV antibody. The amount of radiolabeled PMN adhering to the monolayer was determined after appropriate incubation and washings. The effector binding assay was shown to be dependent on specific anti-HSV antibodies, antibody concentration, HSV viral expression, and inoculation time. This assay system is especially useful for the evaluation of effector to target cell conjugate formation when applied to anchorage target cells.  相似文献   
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BACKGROUND: Sutureless re-anastomosis per laparoscopy is an alternative for microsurgical re-anastomosis by laparotomy in the treatment of sterilized women with renewed child wish. Our aim was to compare pregnancy rates after both surgical techniques. METHODS: We performed a retrospective cohort study in which consecutive women who underwent sutureless re-anastomosis per laparoscopy were compared to women who underwent microsurgical re-anastomosis by laparotomy. Both procedures were performed in neighbouring hospitals in Northern-Brabant, The Netherlands, and women were matched for age. The primary outcome was time to ongoing pregnancy. RESULTS: Overall, we included 41 women who had sutureless re-anastomosis by laparoscopy, and 41 age-matched women who underwent microsurgical re-anastomosis by laparotomy. The number of women who conceived was 20 (15 ongoing pregnancies) in the sutureless laparoscopic group versus 26 (24 ongoing pregnancies) in the laparotomic group, a difference due to a longer follow-up period in the laparotomic group. Time to ongoing pregnancy was comparable in both groups (P=0.46), with 3 year cumulative ongoing pregnancy rates of 45 and 52% respectively. After adjustment for other prognostic factors, the fecundity rate ratio was 0.97 (95% CI 0.26-3.6), indicating a similar performance of the two techniques. CONCLUSION: The simplified stitchless laparoscopic procedure for reversal of tubal sterilization with the use of a tubal splint, clip fixation of the muscularis and fibrin glue resulted in a promising pregnancy rate, which was similar to the pregnancy rate obtained with the microsurgical re-anastomosis per laparotomy.  相似文献   
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OBJECTIVE: Garlic (Allium sativum) has been suggested to affect several cardiovascular risk factors. Its antiatherosclerotic properties are mainly attributed to allicin that is produced upon crushing of the garlic clove. Most previous studies used various garlic preparations in which allicin levels were not well defined. In the present study, we evaluated the effects of pure allicin on atherogenesis in experimental mouse models. METHODS AND RESULTS: Daily dietary supplement of allicin, 9 mg/kg body weight, reduced the atherosclerotic plaque area by 68.9 and 56.8% in apolipoprotein E-deficient and low-density lipoprotein (LDL) receptor knockout mice, respectively, as compared with control mice. LDL isolated from allicin-treated groups was more resistant to CuSO(4)-induced oxidation ex vivo than LDL isolated from control mice. Incubation of mouse plasma with (3)H-labeled allicin showed binding of allicin to lipoproteins. By using electron spin resonance, we demonstrated reduced Cu(2+) binding to LDL following allicin treatment. LDL treatment with allicin significantly inhibited both native LDL and oxidized LDL degradation by isolated mouse macrophages. CONCLUSIONS: By using a pure allicin preparation, we were able to show that allicin may affect atherosclerosis not only by acting as an antioxidant, but also by other mechanisms, such as lipoprotein modification and inhibition of LDL uptake and degradation by macrophages.  相似文献   
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A GroEL-like protein from Bordetella pertussis was purified. This protein was found to have the tetradecameric subunit structure typical of the GroEL family of proteins and to contain epitopes similar to those of other members of this family, including a human GroEL-like protein. Active immunization of neonatal mice with the B. pertussis GroEL-like protein provided little protection against an aerosol challenge with B. pertussis. Antibodies to this protein were elicited in mice by a standard diphtheria-tetanus-pertussis (DTP) vaccine but not by an experimental acellular pertussis vaccine. Since the Bordetella GroEL-like protein was found to contain epitopes similar to those on the mammalian analog, the potential exists that vaccination with standard DTP vaccines may induce antibodies which react with the mammalian GroEL analog.  相似文献   
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Allicin, the main organic allyl sulfur component in garlic, exhibits immune-stimulatory and antitumor properties. Allicin stimulated [(3)H]thymidine incorporation in mouse splenocytes and enhanced cell-mediated cytotoxicity in human peripheral mononuclear cells. Multiple administration (i.p.) of allicin elicited a marked antitumor effect in mice inoculated with B-16 melanoma and MCA-105 fibrosarcoma. The immune-stimulatory and antitumor effects of allicin are characterized by a bell-shaped curve, i.e. allicin at high, supra-optimal concentrations is less effective or inhibitory. Allicin induced activation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) in human peripheral mononuclear cells, and also in wild-type Jurkat T-cells. Allicin failed to activate ERK1/2 in Jurkat T cells that express p21(ras), in which Cys118 was replaced by Ser. These cells are not susceptible to redox-stress modification and activation. We postulate that the immune stimulatory effect of allicin is mediated by redox-sensitive signaling such as activation of p21(ras). It is suggested that the antitumor effect of allicin is related to its immune-stimulatory properties.  相似文献   
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Monocytes produced tumour necrosis factor-alpha (TNF-alpha) upon interaction with infective herpes simplex virus (HSV). Therefore, TNF-alpha and its action were examined in the regulation of anti-viral functions of human polymorphonuclear leucocytes (PMN). The uptake of fluorescein-labelled HSV by human PMN was monitored using flow cytometric analysis. As shown in earlier work, complement-coated herpes virions were bound to PMN but were not internalized. However, after priming with recombinant human TNF-alpha, complement-coated virions were taken up by human PMN. This complement receptor-mediated internalization is a new observation, both because it affects PMN and it is induced by a recombinant cytokine. Recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF), another priming factor of PMN, was unable to induce this phenomenon. By contrast, other parameters of PMN anti-viral defence were enhanced to the same extent by both TNF-alpha and GM-CSF. PMN primed by either TNF-alpha or GM-CSF showed both an enhanced respiratory burst and an increased membrane potential depolarization when triggered by immune complexes containing HSV, antibody and complement. Both primers rendered an enhanced uptake of HSV in the presence of specific antibody and in the presence of both antibody and complement, but they caused no effect on the rate or quantity of processing of phagocytosed HSV particles by PMN. We propose that TNF-alpha and GM-CSF act as effective modulators of PMH to enhance virus removal, especially in inflammatory sites. We tentatively conclude that TNF-alpha together with PMN and complement represent a novel non-specific defence mechanism against HSV.  相似文献   
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BACKGROUND: Despite the disabling nature of chronic urticaria (CU), little is known about the disease's duration or the efficacy of adopting aggressive therapeutic regimens such as cyclosporine A. OBJECTIVES: The aim of this study was to evaluate whether parameters such as angioedema, autologous serum test, anti-thyroid antibodies, and total IgE could predict both CU duration and severity. PATIENTS AND METHODS: One hundred and thirty-nine patients suffering from CU were prospectively followed over a 5-year period for disease duration, severity and the presence of angioedema. Also investigated was the association between these clinical parameters and the subsequent detection of autologous serum test, anti-thyroid antibodies, and total IgE. RESULTS: CU lasted over 1 year in more than 70% of cases and in 14% it still existed after 5 years. Angioedema co-existed or appeared during the course of CU in 40% of patients and was associated with disease duration. Autologous serum test and anti-thyroid antibodies were found positive in 28 and 12% of patients, respectively, compared to none of normal individuals, P = 0.001. CU duration was associated with the presence of both autologous serum test and anti-thyroid antibodies; however, autologous serum test and not anti-thyroid antibodies was found in association with CU severity. CONCLUSION: We demonstrate for the first time that CU duration is associated with clinical parameters such as severity and angioedema, and with laboratory parameters such as autologous serum test and anti-thyroid antibodies. The ability to predict CU duration may facilitate decisions regarding the possible early initiation of cyclosporine A as a means by which to reduce disease severity and duration.  相似文献   
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