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991.
The ethics of research continue to attract considerable debate, particularly when that research is sponsored by partners from the North and carried out in the South. Ethical research should contribute to social value in the country where research is being carried out, but there is significant debate around how this might be achieved and who is responsible. The literature suggests that researchers might employ two inter-related strategies to maximise social value: collaborative partnerships with policy makers and communities from the outset of research, and dissemination of research results to participants, policy makers and implementers once the research is over. These areas have received relatively little empirical attention. In this study, we carried out 40 in-depth interviews to explore the role of collaborative partnerships in health research priority setting, and the way in which research findings are disseminated to aid policy making and implementation in Kenya. Interviewees included policy makers, researchers, policy implementers and representatives of organisations funding health reforms in Kenya. Two policy issues were drawn upon as tracers wherever possible: (1) the introduction of Artemesinin-based Combination Therapies (ACTs), an anti-malarial treatment policy; and (2) Haemophilus influenzae (Hib) vaccine for the prevention of pneumococcal diseases among children. The findings point to significant gaps in the 'research to policy to practice' pathway, particularly for national research institutions with a focus on clinical/biomedical research. These gaps reflect poorly effective partnerships among stakeholders and limit the potential social value of much research. While more investment is needed to establish strong structures for promoting and directing collaboration and partnership, how to target this investment is not entirely clear, especially in the context of the considerable power of the global health agenda and the research financing tied to it.  相似文献   
992.
PURPOSE: Conventional allogeneic stem-cell transplantation (SCT) after a prior failed autograft is associated with a transplant-related mortality rate of 50% to 80%. The aim of the current study was to evaluate the safety and efficacy of sibling, HLA-matched, nonmyeloablative allogeneic SCT with donor lymphocyte infusion (DLI) in patients with lymphoid malignancy after failure of autologous SCT. PATIENTS AND METHODS: A total of 38 patients with refractory, progressive, or relapsed disease after autologous SCT were entered onto this study. The conditioning regimen consisted of the humanized monoclonal antibody CAMPATH-1H, fludarabine, and melphalan. Fifteen of 35 assessable patients received DLI after SCT. RESULTS: Sustained neutrophil engraftment was achieved in 37 recipients, and platelet engraftment was achieved in 35 patients. The estimated transplant-related mortality was 7.9% at day 100 and 20% at 14 months, the median duration of follow-up. Eight patients experienced grade I/II acute graft-versus-host disease (GVHD) after transplantation, but no grade III/IV GVHD was observed in this setting. However, grade III/IV GVHD occurred in seven patients who received DLI. The actuarial overall survival at 14 months was 53%, with a progression-free survival of 50%. DLI produced a further response in three of 15 recipients. CONCLUSION: Nonmyeloablative allogeneic SCT after CAMPATH-1H-containing conditioning is a relatively safe option compared with conventional allogeneic transplantation for patients who have failed previous autologous SCT. The low incidence of early GVHD enabled the subsequent administration of DLI to improve further clinical responses in this poor-risk group of lymphoma and myeloma patients.  相似文献   
993.
表面带电脂质体载药及对小鼠体内弓形虫的作用   总被引:3,自引:0,他引:3  
表面电性是脂质体重要性质之一,本文用1,8-ANS作为探剂,采用荧光法和电泳法测定脂质体的表面电位。离子性药物的包封率及渗漏速度受脂质体表面电性影响,实验表明,脂质体表面电性和药物离子电性相反时,包封率高,渗漏速度慢。以小鼠感染弓形虫做模型,进行体内试验,证明脂质体载药显著优于游离药物的治疗效果。因弓形虫是细胞内寄生的原虫,凡有利于药物入胞的方法,可提高其疗效。此种模型试验简便、准确,其结果对载抗癌药脂质体研究可以借鉴。  相似文献   
994.
Chemotherapy for primary or metastatic hepatic malignancy is limited by poor tumor response and dose-related systemic toxicity. As an alternative to chemotherapy infusion by vein or by the hepatic artery, the authors have developed a percutaneous technique of isolated liver perfusion that allows the regional delivery of high-dose chemotherapy to the liver with little systemic toxicity. After placement of a hepatic artery infusion catheter, an 18-F double-balloon catheter is placed into the inferior vena cava through the opposite femoral vein. Balloons are inflated above and below the hepatic veins, thus isolating hepatic venous outflow. The effluent passes through fenestrations in the catheter and is pumped through charcoal hemoperfusion filters where the drug is removed. The filtered blood is returned to the patient through the internal jugular vein. Fifteen treatments have been conducted in eight patients in a phase I dose-escalation study with use of 5-fluorouracil (5-FU). While it is premature to assess tumor response to isolated liver perfusion, the data demonstrate that the procedure is safe and is tolerated by patients. Pharmacokinetic studies show a 5-FU extraction of up to 85%, with minimal drug leakage into the systemic circulation. This technique shows potential for improving liver tumor response while decreasing systemic toxicity.  相似文献   
995.
1. Kenyan children with uncomplicated malaria given oral halofantrine (HF; non-micronised suspension; 8 mg base kg-1 body weight 6 hourly for three doses) showed wide variation in the disposition of HF and desbutylhalofantrine (HFm). 2. Eight Kenyan children with severe (prostrate) falciparum malaria who were receiving intravenous quinine, were given the same HF regimen by nasogastric tube. One patient had undetectable HF and two had undetectable HFm at all times after drug administration. 3. The mean AUC(0,24 h) of HF in prostrate children was half (7.54 compared with 13.10 micrograms ml-1 h) (P = 0.06), and that for HFm one-third (0.84 compared with 2.51 micrograms ml-1 h) (P < 0.05) of the value in children with uncomplicated malaria. 4. Oral HF may be appropriate for some cases of uncomplicated falciparum malaria in Africa, but in patients with severe malaria, the bioavailability of HF and HFm may be inadequate.  相似文献   
996.
苦楝化学成份的研究   总被引:7,自引:0,他引:7  
从苦楝(Melia azedarach L.)果中分得苦楝新醇(Ⅰ),苦楝醇(Ⅱ)、苦楝酮(Ⅲ)、苦楝二醇(Ⅳ)、香草醛(Ⅴ)和香草酸(Ⅵ)。根据波谱(IR,MS,1HNMR,13CNMR)分析和理化常数测定,确定了它们的结构。其中苦楝新醇(Ⅰ)为新化合物,对菜青小虫有一定的拒食活性。  相似文献   
997.
从苦楝(Melia azedarach L.)果中分得苦楝新醇(Ⅰ),苦楝醇(Ⅱ)、苦楝酮(Ⅲ)、苦楝二醇(Ⅳ)、香草醛(Ⅴ)和香草酸(Ⅵ)。根据波谱(IR,MS,~1HNMR,~(13)CNMR)分析和理化常数测定,确定了它们的结构。其中苦楝新醇(Ⅰ)为新化合物,对菜青小虫有一定的拒食活性。  相似文献   
998.
Specificity of IgG autoantibodies that react with random red cell samples but not with cells treated with 2-aminoethylisothiouronium bromide (AET)-previously was related to the Kell blood group system. We now describe an IgG autoantibody, from a patient who died with autoimmune hemolytic anemia, that reacted with random red cell samples, Ko cells, and with cells treated with a dithiothreitol-papain solution, but did not react with AET-treated cells or with Rhnull cells. Serological reactivity of the autoantibody is unlike that of IgG autoantibodies that do not react only with Rhnull cells. It appears that the reactive antigen is not part of the Kell or Rh systems, but is probably modified by the membrane anomaly present in Rhnull red cells.  相似文献   
999.
1 Mojave toxin isolated from the venom of the Mojave rattlesnake (Crotalus scutulatus scutulatus) produced an irreversible blockade of the contractile response of the mouse hemidiaphragm to stimulation of the phrenic nerve in vitro, at concentrations of 0.16 to 20 μg/ml; the response to direct stimulation was not affected over a testing period of several hours.  相似文献   
1000.
取代四氢异喹啉衍生物的合成及其生物活性   总被引:7,自引:0,他引:7  
粉防己碱有钙拮抗作用,临床试用于治疗高血压,其裂解产物钙拮抗作用降低,但有α-肾上腺素能受体拮抗作用,本文以裂解物为先导化合物设计合成了两类取代的四氢异喹啉衍生物Ⅲ及Ⅳ。初步药理试验表明:大部分化合物有α-肾上腺素能受体拮抗作用,少数化合物钙拮抗活性有所增强,其中Ⅲ15,19对正常麻醉大鼠有一定的降压作用、Ⅳ17,19对实验性动物心律失常有明显的保护作用。部分化合物量化计算表明:化合物与α1-受体作用方式可能是形成电荷转移复合物。  相似文献   
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