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41.
Background: Mice immunized with murine mammary carcinoma cells genetically engineered to secrete interleukin-2 (IL-2) are rendered resistant to subsequent challenge with unmodified tumor cells, and in the case of mice bearing established tumors, the rate of development of pulmonary metastases is reduced. Despite these encouraging animal results, little is known about the induction of antitumor immunity by IL-2 gene transfer in human breast cancer. Methods: Adenovirally mediated IL-2 gene transfer was performed in 12 tumor fragment cultures established from seven primary breast cancers. Autologous tumor infiltrating lymphocytes (TILs) or peripheral blood mononuclear cells (PBMCs) were cocultured with transduced tumor fragments, and changes in phenotype and cytotoxicity were measured. Results: IL-2 was never detectable in the untransduced cultures, but it peaked at 5.0—1,324.8 ng/ml in the transduced cultures. Lymphocyte counts declined in all untransduced cultures, but they increased two- to sevenfold in four transduced cultures. CD4:CD8 ratios decreased from a mean of 2.11 at baseline to 1.27 after stimulation in coculture (p=0.03). Expansion of lymphocytes expressing the natural killer cell phenotype (CD3CD56+) occurred in only one culture, but the CD3+CD56+ population increased in four of six cultures. Lymphocytes from four of 10 cocultures generated significant cytotoxicity against allogeneic breast cancer cells. Induction of cytotoxicity correlated with expansion of the CD3+CD56+ phenotype (R2=0.805, p=0.02). Conclusions: IL-2 gene expression by human breast cancer causes expansion of CD3+CD56+ cytotoxic lymphocytes. This phenotype is consistent with that of a non-major histocompatibility complex (MHC)-restricted cytokine induced killer cell population previously described. Opinions, interpretations, conclusions and recommendations are those of the author and are not necessarily endorsed by the U.S. Army. Presented at the 49th Annual Cancer Symposium of The Society of Surgical Oncology, Atlanta, Georgia, March 21–24, 1996.  相似文献   
42.
白细胞介素—2新的功能位点及其中枢镇痛作用   总被引:2,自引:0,他引:2  
白细胞介素-2(IL-2)不仅是重要的免疫调节因子,而且还具有重要的中枢调节作用。本实验以钾离子透入引起大鼠甩尾反应为指标,发现侧脑室注射IL—2能显著提高动物痛阈,并能被纳洛酮所阻断,表示IL-2的中枢镇痛作用可能与阿片受体有关。利用基因定位突变技术获得的无免疫活性IL-2实查体仍具有中枢镇痛作用,表明IL—2分子上发挥镇痛和免疫调节作用的功能位点是相互独立的。纳洛酮能够阻断IL—2的中枢镇痛作用,而不能影响IL—2增殖CTLL-2细胞的作用,提示IL-2发挥镇痛和免疫调节作用可能通过不同的受体途径。IL-2分子中第45位Tyr残基突变为Val后,虽仍保留了免疫活性,但丧失了镇痛功能,表示45位Tyr残基是IL—2发挥中枢镇痛功能的关键残基之一。我们推测IL—2的镇痛功能位点可能在IL—2分子中第45位Tyr残基附近区域。  相似文献   
43.
Myotonic dystrophy is an inherited multi-system disease. Its pathophysiology leading to muscle malfunction and damage is not well understood. 23Na NMR spectroscopy was applied here for an in vivo comparative study of the calf muscles of 7 myotonic dystrophy patients at various stages of the disease and 11 healthy volunteers. Both the total sodium content, expressed as the ratio of the 23Na and 1H water signals, and the fast transverse relaxation time, T21, determined from the triple quantum-filtered spectra, increased in correlation with the severity of the disease. The results demonstrate that 23Na NMR enables the quantitation of myotonic dystrophy progression.  相似文献   
44.
Effect of interleukin-8 on glomerular sulfated compounds and albuminuria   总被引:2,自引:0,他引:2  
To evaluate the effect of interleukin-8 (IL8) on glomerular basement membrane (GBM) sulfated compounds and albuminuria, we infused IL8 in 1% bovine serum albumin (BSA) for 5 days into the left renal artery of Holtzman male rats at the rate of 10 μl/h using an osmotic pump. Control rats received 1% BSA. A significant increase in urinary albumin/creatinine ratio was seen on the last day of IL8 infusion (0.38±0.11, mean ± SEM) when compared with albumin/creatinine ratio prior to infusion (0.19±0.04, P = 0.04). No significant differences in urinary albumin excretion prior to and after infusion of 1% BSA were observed. On the last day of infusion, rats were injected with 35sulfate (1.0 mCi/200 g body weight) intraperitoneally and killed after 8 h. Glomeruli were isolated and GBM obtained. After 5 days of IL8 administration, there was a significant increase in 35sulfate uptake by GBM of the infused kidney (76±10 cpm/dry glomerular weight, mean ± SEM) compared with the uptake seen in the contralateral kidney (53±9, P = 0.05). The in vivo infusion of IL8 increased the 35sulfate uptake by GBM and augmented the urinary albumin/creatinine ratio, suggesting that IL8 may induce albuminuria by altering the metabolism of the GBM sulfated compounds. This hypothesis needs to be confirmed by studies on glomerular charge selectivity and GBM anionic sites during the course of the infusion. Moreover, the persistence of the effect needs to be evaluated by prolonging the infusion for more than 5 days. Received June 3, 1996; received in revised form and accepted October 18, 1996  相似文献   
45.
That maternal inflammation adversely affects fetal brain development is well established. Less well understood are the mechanisms that account for neurodevelopmental disorders arising from maternal inflammation. This review seeks to begin an examination of possible sites and mechanisms of action whereby inflammatory cytokines - produced by the mother or by the fetal brain - could impact the developing fetus. We focus first on the placenta where cytokines maintain the immunological environment that prevents maternal rejection of the fetus. Following a brief examination of placental transfer of maternal cytokines, the focus turns on embryonic microglia, early and ubiquitous residents of the developing brain. Finally, a more intense examination of interleukin-6 (IL-6) and bone morphogenetic proteins (BMPs) provides examples of glial- or maternal-derived cytokines that are known to have profound effects on developing systems and that could, if dysregulated, have undesirable consequences for brain development.  相似文献   
46.
目的 观察溴环己胺醇预先给药对大鼠盐酸吸入性肺损伤是否具有保护作用,并探讨其可能机制。方法30只健康 SD 大鼠,随机分成3组,A 组:生理盐水吸入组;B组:稀盐酸吸入组;C组:稀盐酸吸入 溴环己胺醇处理组,每组10只。C 组腹腔注射溴环己胺醇,1次/d,连续3d,A、B 组以等体积生理盐水代替。第3天注药后30min,B、C 组气管注入pH 值为1.25的稀盐酸1.2ml/kg,制成盐酸吸入性肺损伤模型,A 组气管注入生理盐水1.2ml/kg。观察注药后5h 动脉血气、氧合指数(PaO_2/FiO_2)、肺湿/干重比(W/D)、肺组织及血清中肿瘤坏死因子-α(TNF-α)、白细胞介素-8(IL-8)水平。结果 与 A 组比较,B、C 组 PaO_2、PaO_2/FiO_2降低(P<0.01),B、C 组W/D、B 组肺组织 TNF-α、IL-8含量、血清 IL-8浓度升高(P<0.01)。与 B 组比较,C 组 PaO_2、PaO_2/FiO_2升高(P<0.01),C 组W/D、肺组织TNF-α、IL-8含量及血清 IL-8浓度降低(P<0.01)。结论 溴环己胺醇可能通过抑制 TNF-α、IL-8炎症因子的产生和释放机制对盐酸吸入性损伤肺产生保护作用。  相似文献   
47.
脑胶质瘤白细胞介素-6自分泌或旁分泌环路的研究   总被引:2,自引:0,他引:2  
目的 研究白细胞介素 6(IL 6) /IL 6受体 (IL 6R)自分泌或旁分泌环路与脑胶质瘤的关系。方法 采用逆转录 聚合酶链反应 (RT PCR)方法检测IL 6和IL 6R基因在 4株脑胶质瘤细胞株、62例脑胶质瘤组织标本、5例良性脑膜瘤组织和 5例人正常脑胶质细胞中的表达 ;将IL 6单抗 (McAb)或IL 6RMcAb与脑胶质瘤细胞共同孵育 ,四甲基偶氮唑蓝 (MTT)比色法检测对细胞生长的抑制作用。结果 脑胶质瘤细胞株C6、9L、U 2 5 1和SHG44均有IL 6和IL 6R的表达 ,脑胶质瘤组织标本中 47例 (75 .81% )表达IL 6、5 2例 (83 .87% )表达IL 6R、41例 (66.13 % )同时表达IL 6和IL 6R ;良性脑膜瘤组织 4例表达IL 6,人脑正常胶质细胞仅有IL 6弱表达 ,两者均无IL 6R表达。IL 6McAb和IL 6RMcAb能够显著抑制脑胶质瘤细胞的增殖 ,并存在剂量依赖关系(P <0 .0 1)。结论 脑胶质瘤很可能存在IL 6/IL 6R自分泌或旁分泌环路 ,阻断此环路可以明显抑制胶质瘤细胞的恶性增殖  相似文献   
48.
Summary Levels of soluble IL-2 receptors, IL-6, soluble CD23, soluble CD14 and ECP (eosinophilic cationic protein) were measured as markers of T-cell, B-cell, monocyte and eosinophilic leucocyte activation in 26 patients with atopic dermatitis (AD) on admission to (A) and at discharge from (D) the Department of Dermatology in Zurich. The serum levels of sIL-2R, IL-6, sCD23, sCD14 and ECP were significantly elevated in AD patients in comparison with the normal values of healthy donors. A significant decrease in sIL-2R (p=0.0093) and in sCD14 (p=0.0134) levels was demonstrated between A and D, correlating with the improvement in the skin intensity score (SIS). In addition, a significant correlation of the sCD14 levels and the SIS at A was demonstrated (p=0.0415). These results also incriminate monocytes in the pathogenesis of AD, indicating that, besides sIL-2R and ECP, SCD14 could also be a possible marker for the disease activity.  相似文献   
49.
目的 探讨白细胞介素-1β(Interleukin-1,IL-1β)在谷氨酸钠致痫大鼠中对海马兴奋性G-蛋白α亚基(stimulated G-protein α subunit,Gsα)蛋白表达的影响,为阐明IL-1β在致痫中的作用机制提供线索。方法 免疫组织化学方法结合行为观察(SD大鼠随机分为对照组、GluNa组、IL-1β GluNa组、rhIL-1ra IL1β GluNa组和D-AP-5 IL-1β GluNa组)。结果 行为观察显示,IL-1β GluNa组大鼠痫性发作潜伏期(平均2min)较其他组(平均6min)明显缩短,且发作程度(Ⅲ~Ⅳ级)较其他组(Ⅰ~Ⅲ级)严重;对照组无痫性发作。免疫组织化学染色显示,Gsα蛋白在海马各区均有表达,IL-1β GluNa组大鼠在齿状回、CAl区和CA3区Gsa表达较其他组明显增强。结论 IL-1β参与致痫,且在谷氨酸致痫中可能通过Gs蛋白介导发挥作用。  相似文献   
50.
目的探讨人脑胶质瘤白介素13受体(IL-13R)基因表达与肿瘤增殖活性的关系。方法对6例正常脑组织,50例人脑胶质瘤和2个脑瘤体外细胞系采用RT—PCR法和免疫组织化学法检测IL-13R。结果人脑胶质瘤组织IL-13RαmRNA总阳性表达率70%,正常脑组织中仅1例有极弱的表达;2例恶性胶质瘤体外细胞系均高表达。IL-13RαmRNA表达率和表达丰度与胶质瘤分级(前者rs=0.87,P〈0.01;后者rs=0.69,P〈0.01)、肿瘤增殖活性Ki-67LI(r=0.64,P〈0.01)呈正相关,即胶质瘤恶性程度越高,IL-13RαmRNA表达率和表达水平越高。结论IL-13Rα基因在人脑胶质瘤中表达上升,与肿瘤的分级和肿瘤增殖活性呈正相关,可作为预测某些肿瘤治疗效果及监测复发的指标之一。  相似文献   
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