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21.
目的:探讨BCG初次免疫(BCG-prime),结核杆菌共表达DNA疫苗加强免疫(DNA疫苗-boost)的策略对小鼠的免疫效果。方法:将BCG及结核杆菌重组DNA疫苗依次免疫小鼠,通过检测CTL和NK细胞的杀伤活性和特异性淋巴细胞增殖,以及小鼠血清抗体及细胞因子的水平,观测BCG-prime、共表达结核杆菌Ag85A/GM-CSFDNA疫苗boost策略对小鼠的免疫效果。结果:采用prime-boost免疫策略组的小鼠CTL的杀伤活性明显增强、特异性淋巴细胞明显增殖、IFN-γ的水平明显增高,NK细胞杀伤活性与对照组相比也有一定提高,但未超过BCG单独免疫效果。免疫小鼠血清特异性抗体的滴度超过单独DNA疫苗免疫组。结论:在采用BCG-prime-结核杆菌DNA疫苗boost免疫策略后,能增强对小鼠的免疫效应,尤其是Th1型细胞免疫反应增强明显,为进一步在动物体内进行保护性效应试验的研究提供了实验依据。  相似文献   
22.
卡介苗多糖核酸对支气管哮喘合并鼻炎患儿治疗的研究   总被引:3,自引:0,他引:3  
目的 探讨卡介苗多糖核酸(BCG-PSN)对支气管哮喘合并鼻炎患儿Th1/Th2功能及肺通气功能的影响.方法 37例哮喘患儿随机分为治疗组和对照组两组.按照分级治疗的标准给与相应的糖皮质激素吸入治疗,治疗组加用BCG-PSN,随访6个月,比较治疗前和治疗后血清IFN-γ、IL-4的浓度及IFN-γ/IL-4比值、血浆总IgE、肺功能、鼻炎积分、哮喘发作需急诊就诊的次数、呼吸道感染的次数.结果治疗后治疗组,IL-4、IgE明显下降,IFN-γ及IFN-γ/IL-4比值明显升高;差异有统计学意义(P<0.05),而对照组无明显改变,差异无统计学意义(P<0.05).两组肺功能均明显改善,差异有统计学意义(P<0.05).治疗组哮喘发作需急诊就诊的次数为(0.81±0.20)次,对照组为(1.72±0.80)次,差异有统计学意义,(t=4.15,P<0.05);治疗组呼吸道感染(1.15±0.55)次,对照组(3.21±0.73)次,差异有统计学意义,(t=3.98,P<0.05);治疗组鼻炎发作(1.31±0.42)次、对照组(1.11±0.39)次,差异无统计学意义,(t=2.31,P<0.05).结论 BCG-PSN具有纠正Th1/Th2失衡,减轻气道炎症,改善肺通气功能,提高免疫力的作用.对于哮喘合并过敏性鼻炎的患儿,除针对气道慢性炎症使用糖皮质激素进行抗炎治疗外,同时应重视免疫调节治疗.  相似文献   
23.
The regulatory effect of prostaglandin (PG) E2 and a cyclooxygenase (COX) inhibitor on Bacille Calmette-Guérin (BCG)-induced macrophage cytotoxicity in a bladder cancer cell, MBT-2, was studied in vitro. BCG stimulated thioglycollate-elicited murine peritoneal exudate cells (PEC) to induce cytotoxic activity and to produce cytokines such as interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha and PGE2. NS398, a specific COX-2 inhibitor, and indomethacin (IM), a COX-1 and COX-2 inhibitor, enhanced viable BCG-induced cytotoxic activity and IFN-gamma and TNF-alpha production of PEC. However, NS398 and IM did not enhance these activities induced by killed BCG. Enhanced cytotoxicity was mediated by increased amounts of IFN-gamma and TNF-alpha. Exogenous PGE2 reduced cytotoxic activity and IFN-gamma and TNF-alpha production of PEC. These results suggest that PGE2 produced by BCG-activated macrophages has a negative regulatory effect on the cytotoxic activity of macrophages. Accordingly, a PG synthesis inhibitor may be a useful agent to enhance BCG-induced antitumour activity of macrophages.  相似文献   
24.
Recognition of mycobacteria by the innate immune system is essential for the development of an adaptive immune response. Mycobacterial antigens stimulate antigen presenting cells (APCs) through distinct Toll-like receptors (TLRs) resulting in rapid activation of the innate immune system. The role of TLRs during infection with Mycobacterium bovis Bacillus Calmette-Guérin (BCG) has been evaluated for TLR2 and TLR4 only. Surprisingly, despite the fact that immune stimulatory CpG-motifs have been originally derived from BCG, for the vaccine strain the role of TLR9 has not been addressed before. To identify the set of TLRs involved in the recognition of BCG, we infected bone marrow-derived macrophages and bone marrow-derived dendritic cells (Flt3-ligand generated DCs) from TLR2, TLR3, TLR4, TLR7, TLR9, MyD88 knockout, TLR2/4 and TLR2/4/9 multiple knockout mice. The degree of activation and stimulation was determined by TNFα, IL-6 and IL-12p40 ELISA. Activation of DCs was measured by surface expression of the costimulatory molecule CD86. We observed the most dramatic reduction of the inflammatory response for TLR2-deficient antigen presenting cells. Both macrophages and DCs produce markedly decreased amounts of TNFα and IL-6 in the absence of TLR2 whereas no significant reduction could be observed for TLR3, 4, 7, 9 single TLR-knockouts. However, IL-12 production in DCs appears not exclusively dependent on TLR2 and only in TLR2/4/9-deficient DCs BCG-induced IL-12 is reduced to background levels. Similarly, up-regulation of CD86 is abolished only in TLR2/4/9-deficient DCs supporting a role of TLR9 in the recognition of M. bovis BCG by murine dendritic cells.  相似文献   
25.
26.
Children in Malawi receive bacille Calmette-Guérin (BCG) vaccination within the first 3 days of life. Thus, we hypothesized that Malawian children infected with the human immunodeficiency type 1 virus (HIV-1) might be particularly vulnerable to dissemination of the BCG Mycobacterium bovis strain with which they were vaccinated. Following informed consent by parents, we studied children admitted to a Malawi general hospital during the 1998 wet and dry seasons. Blood from cohorts of acutely ill children was cultured for bacteria, including mycobacteria, and fungi, and tested for anti-HIV-1 antibodies. It was shown that non- typhi Salmonella and Escherichia coli were the predominant bloodstream pathogens during the wet and dry seasons, and that bloodstream dissemination of the BCG M. bovis strain is uncommon in HIV-1-infected children who receive the BCG vaccine.  相似文献   
27.
Interleukin-18 (IL-18) has been demonstrated to synergize with BCG for induction of a T-helper-type 1 (Th1) immune response. Since successful treatment of superficial bladder cancer with BCG requires proper induction of Th1 immunity, we have developed a recombinant (r) BCG strain that functionally secretes mouse (m) IL-18. This rBCG-mIL-18 strain significantly increased production of the major Th1 cytokine IFN-gamma in splenocyte cultures, at levels comparable to that elicited by control BCG plus exogenous rIL-18. IFN-gamma production by splenocytes was eliminated by addition of neutralizing anti-IL-18 antibody. Endogenous IL-12 played a favourable role whereas IL-10 played an adverse role in rBCG-mIL-18-induced IFN-gamma production. Enhanced host antimycobacterial immunity was observed in mice infected with rBCG-mIL-18 which showed less splenic enlargement and reduced bacterial load compared to control mice infected with BCG. Further, splenocytes from rBCG-mIL-18-infected mice, in response to BCG antigen, displayed increased production of IFN-gamma and GMCSF, decreased production of IL-10, elevated cellular proliferation and higher differentiation of IFN-gamma-secreting cells. rBCG-mIL-18 also enhanced BCG-induced macrophage cytotoxicity against bladder cancer MBT-2 cells in a dose-dependent manner. Neutralizing all endogenous macrophage-derived cytokines tested (IL-12, IL-18 and TNF-alpha) as well as IFN-gamma severely diminished the rBCG-mIL-18-induced macrophage cytolytic activity, indicating a critical role for these cytokines in this process. Cytokine analysis for supernatants of macrophage-BCG mixture cultures manifested higher levels of IFN-gamma and TNF-alpha in rBCG-mIL-18 cultures than in control BCG cultures. Taken together, this rBCG-mIL-18 strain augments BCG's immunostimulatory property and may serve as a better agent for bladder cancer immunotherapy and antimycobacterial immunization.  相似文献   
28.
目的从循证视角建立公立医院优势学科病种绩效管理工具。方法以波士顿矩阵理论为指导,以“病种均次毛利率、病种均次住院日”为主要指标,“日均毛利率”为辅助指标,采用Microsoft office EXCEL 365 软件进行分析。结果2019年骨科平均住院日为4.99 d,均次平均毛利率为23.62%,日均毛利率平均值为4.73%。骨科200例以上病种、不同亚专科病区病种、同一亚专科病区内不同病种、不同亚专科病区相同病种,绩效均存在差异。结论 管理者应对不同病种绩效指标进行适当校正,探索精细化病种诊疗与管理模式。  相似文献   
29.
目的:观察BT-BAK细胞与BCG膀胱腔内灌注治疗对患者全身免疫功能的影响。方法:由手术切除的膀胱瘤标本制备膀胱肿瘤可溶性抗原,以BCG为佐剂,从PBMNC中诱导出抗膀胱肿瘤特异性细胞毒性BT-BAK细胞,临床选择72例浅表性膀胱癌术后患者随机平均分成2组分别进行BT-BAK和BCG的膀胱腔内灌注治疗。于不同阶段采用ELISA法测定患者外周血中IL-2、TNF-α及IFN-γ的含量;观察治疗后患者PBMNC对T24膀胱肿瘤细胞株杀伤活性的变化。结果:BT-BAK组患者血清中IL-2、TNF-α及IFN-γ的水平均较治疗前明显提高(P<0.01);患者PBMNC对T24膀胱肿瘤细胞株的杀伤活性显著增强(P<0.01)。BT-BAK组上述指标均高于BCG组(P<0.05)。平均随访18.16个月,两组的复发率分别为2.7%和11.11%。结论:BT-BAK细胞及其培养上清进行膀胱腔内灌注治疗,能够有效提高膀胱癌术后患者的全身免疫水平,降低膀胱癌的术后复发率。  相似文献   
30.
目的:了解我县儿童接种卡介苗接种的免疫情况。方法:1999年7-8月,以城区范围内卡介苗接种16周以后的1-4岁儿童为对象进行结核菌素试验,72小时后查验反应结果。注射部位硬结反应≥5mm为阳性反应,同时记录儿童接种卡俚苗后的卡痕大小。结果:我县城区1-4儿童结核菌素试验阳转率为45.9%,其中0-岁组儿童结核菌素是性转变达88.9%,对结核病的免疫水平较低。结核菌素试验阳性率性别间无显性差异。止痕<5mm的儿童,1-4岁年龄组的结核菌素阳性转率逐渐增大,结论:城区中存在一定的传染源,对阳性转率较低的原因应进行探索并提出预防方法和措施。  相似文献   
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