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41.
Mycophenolic acid Observational REnal transplant (MORE) was a prospective, observational study of de novo kidney transplant patients receiving mycophenolic acid (MPA). Four‐yr data on 904 patients receiving tacrolimus and enteric‐coated mycophenolate sodium (EC‐MPS) or mycophenolate mofetil (MMF) were analyzed to evaluate immunosuppression and graft outcomes in African American (AA, n = 218) vs. non‐AA (n = 686) patients. Mean tacrolimus dose was higher in AA vs. non‐AA patients but mean tacrolimus trough concentration was similar. Use of the recommended MPA dose in AA patients decreased from 78.9% at baseline to 33.1% at year 3. More AA patients received the recommended MPA dose with EC‐MPS than MMF at month 6 (56.2% vs. 35.7%, p = 0.016) and month 36 (46.6% vs. 16.7%, p = 0.029), with no safety penalty. Significantly, more AA patients received corticosteroids than non‐AA patients. Biopsy‐proven acute rejection was higher in AA vs. non‐AA patients (18.9% vs. 10.7%, p = 0.003), as was graft loss (10.9% vs. 4.4%, p = 0.003); differences were confirmed by Cox regression analysis. Patient survival was similar. Estimated GFR was comparable in AA vs. non‐AA patients. Kidney allograft survival remains lower for AA vs. non‐AA recipients even under the current standard of care.  相似文献   
42.
EC0746 is a rationally designed anti-inflammatory drug conjugate consisting of a modified folic acid-based ligand linked to a γ-hydrazide analog of aminopterin. In this report, EC0746's effectiveness was evaluated against experimental retinal S-antigen (PDSAg) induced autoimmune uveitis (EAU) and myelin-basic-protein induced autoimmune encephalomyelitis (EAE). In both models, functional FR-β was detected on activated macrophages in local (retinal or central-nervous-system, respectively) and systemic (peritoneal cavity) sites of inflammation. In myelin-rich regions of EAE rats, an increased uptake of 99mTc-EC20 (etarfolatide; a FR-specific radioimaging agent) was also observed. EC0746 treatment at disease onset suppressed the clinical severity of both EAU and EAE, and it strongly attenuated progressive histopathological changes in the affected organs. In all parameters assessed, EC0746 activity was completely blocked by a benign folate competitor, suggesting that these therapeutic outcomes were specifically FR-β mediated. EC0746 may emerge as a useful macrophage-modulating agent for treating inflammatory episodes of organ-specific autoimmunity.  相似文献   
43.
低氧促进P19细胞向多巴胺能神经元分化   总被引:1,自引:0,他引:1       下载免费PDF全文
目的观察低氧对P19细胞神经分化的影响,针对其向多巴胺能神经元分化的现象及机制进行探讨。方法实验分为常氧组(20%O2)和低氧组(3%O2,每天低氧10 m in)。对诱导分化的神经元采用免疫细胞化学染色方法鉴定。用流式细胞术及W estern b lot检测多巴胺能神经元,高效液相色谱法测定分泌的多巴胺。用RT-PCR技术检测低氧诱导因子HIF-1αmRNA水平。结果①在分化的P19细胞中,低氧组神经元含量高于常氧组(P<0.05),低氧组多巴胺能神经元含量及所分泌的多巴胺显著高于常氧组(P<0.001);②低氧组诱导期HIF-1αmRNA表达水平明显高于常氧组。结论低氧可以促进P19细胞的神经分化,尤其促进P19细胞向多巴胺能神经元分化,HIF-1α可能在其中起了一定作用。  相似文献   
44.
目的:系统评价重组结核杆菌融合蛋白(EC)相较于结核菌素纯蛋白衍生物(TB-PPD)用于诊断结核分枝杆菌(Mycobacterium tuberculosis,MTB)感染的有效性和安全性。方法:检索临床指南数据库、生物医学文献数据库、卫生行政部门和行业协会官方网站及不良反应监测官方网站,检索时间均自建库截止到2022年2月。英文检索词:Recombinant Mycobacterium tuberculosis fusion protein、CFP10/ESAT6;中文检索词:重组结核分枝杆菌融合蛋白、重组结核杆菌融合蛋白、宜卡、CFP10/ESAT6。收集重组结核杆菌融合蛋白(EC)和结核菌素纯蛋白衍生物(TB-PPD)诊断MTB感染有效性和安全性的指南、共识、团体标准、系统评价和原始研究等。由2名研究者独立筛选文献、提取资料并评价纳入研究的偏倚风险,根据异质性大小采用Meta分析或描述性分析。结果:纳入指南2部、专家共识3篇、团体标准2部,均指出重组结核杆菌融合蛋白(EC)和结核菌素纯蛋白衍生物(TB-PPD)可用于诊断MTB感染和结核病辅助诊断。纳入系统评价1篇,结果显示,重组...  相似文献   
45.
The use of small interfering RNAs (siRNAs) has been under investigation for the treatment of several unmet medical needs, including acute lung injury/acute respiratory distress syndrome (ALI/ARDS) wherein siRNA may be implemented to modify the expression of pro-inflammatory cytokines and chemokines at the mRNA level. The properties such as clear anatomy, accessibility, and relatively low enzyme activity make the lung a good target for local siRNA therapy. However, the translation of siRNA is restricted by the inefficient delivery of siRNA therapeutics to the target cells due to the properties of naked siRNA. Thus, this review will focus on the various delivery systems that can be used and the different barriers that need to be surmounted for the development of stable inhalable siRNA formulations for human use before siRNA therapeutics for ALI/ARDS become available in the clinic.  相似文献   
46.
罗比卡因及复合芬太尼硬膜外麻醉对运动阻滞EC50的影响   总被引:2,自引:3,他引:2  
目的测定罗比卡因单独使用以及复合不同浓度芬太尼用于硬膜外麻醉时,分别产生运动阻滞的半数有效浓度(effective concentration in 50%patients,EC50),从而确定硬膜外使用芬太尼对罗比卡因硬膜外麻醉产生运动阻滞效果的影响.方法选择ASA Ⅰ~Ⅱ级下肢及肛周会阴部择期手术患者165例,随机分为五组,每组33人.选择L2~3或L3~4硬膜外穿刺,头向置管4 cm成功后,以5 ml/min的速度向硬膜外腔缓慢注入15 ml配置好的药液,Ⅰ组:单纯罗比卡因;Ⅱ组:罗比卡因复合1μg/ml芬太尼;Ⅲ组:罗比卡因复合2μg/ml芬太尼;Ⅳ组:罗比卡因复合3μg/ml芬太尼;Ⅴ组:罗比卡因复合4μg/ml芬太尼.各组中第1位患者向硬膜外腔注入的罗比卡因浓度均为0.425%,其后各患者所用浓度按序贯法进行调整,浓度变化梯度定为0.025%.改良Bromage评分等于4分者为无效运动阻滞,低于4分时为有效运动阻滞.根据Dixon和Massey法[1]计算各组运动阻滞的EC50值.结果五组入选患者中,12例结果显示可疑而退出,根据实际进入的153例,Ⅱ~Ⅴ组罗比卡因运动阻滞EC50值与Ⅰ组比较,均无显著性差异.结论罗比卡因复合低浓度芬太尼(0~4μg/ml)用于硬膜外麻醉时,对罗比卡因产生运动阻滞的EC50无明显影响.  相似文献   
47.
目的观察核桃青皮提取物对人食管癌细胞增殖的抑制作用.方法:用MTT法分别测定核桃青皮粗提物和核桃青皮提取物没食子酸、乙酸乙酯、紫杉叶素、7-D-芹菜糖-儿茶酚对食管癌细胞EC9706和KYSE150的增殖抑制率,并用Western Blot检测不同药物处理后食管癌细胞中细胞周期相关蛋白CyclinD1的蛋白表达.结果:核桃青皮粗提物、没食子酸和乙酸乙酯能抑制食管癌细胞的增殖,其作用呈明显剂量依赖性,当药物浓度增加至80 μg/mL时,对KYSE150的抑制率分别为82.75% 、90.51%、88.36%,对EC9706的抑制率分别为85.54% 、87.21%、85.17%.与对照组相比,3种药物均会显著抑制KYSE150和EC9706细胞中CyclinD1的表达.结论:核桃青皮提取物对食管癌细胞系的增殖有较强的抑制作用,其机制可能与引起细胞周期阻滞有关.  相似文献   
48.
Lu ZM  Liu HT  Xu PR  Hou GQ  Xue LX 《癌症》2007,26(10):1074-1079
背景与目的:早期的研究显示,Notch1信号途径与肿瘤的发生密切相关,在细胞的生长、增殖、分化和凋亡中起着十分重要的作用.本研究旨在研究Notch1基因在食管鳞癌EC9706细胞中的表达及其对EC9706细胞凋亡的影响.方法:通过免疫细胞化学方法检测Notch1基因在EC9706细胞中的表达.采用RT-PCR技术扩增Notch1基因,构建真核表达载体pcDNA3.1-Notch1(命名为pcNICD),转染EC9706细胞,利用RT-PCR及Western blot检测稳定转染pcNICD 载体、转染pcDNA3.1空载体及未处理的EC9706细胞中Notch1的表达,另通过流式细胞仪检测未处理、转染pcDNA3.1和转染pcNICD的EC9706细胞的凋亡.结果:EC9706细胞中发现Notch1基因的表达.与未处理的和转染pcDNA3.1的EC9706细胞相比,转染pcNICD的EC9706细胞中Notch1基因的mRNA和蛋白表达水平均明显增加,大约增加3倍(P<0.05);但未处理的和转染pcDNA3.1的EC9706细胞中Notch1的表达差异无统计学意义(P>0.05).流式细胞检测结果显示,在未处理的和转染pcDNA3.1的EC9706细胞中,细胞凋亡率差异无统计学意义(P>0.05);但与与未处理的和转染pcDNA3.1的EC9706细胞相比.转染pcNICD的EC9706细胞转染后24 h、48 h和72 h时细胞凋亡率明显增加(P<0.01).结论:Notch信号途径的激活引起食管鳞癌EC9706 细胞的凋亡.提示Notch1基因有可能成为治疗食管鳞癌的新靶点.  相似文献   
49.
Ribosome-inactivating proteins (RIPs) are rRNA N-glycosylases from plants (EC 3.2.2.22) that inactivate ribosomes thus inhibiting protein synthesis. The antiviral properties of RIPs have been investigated for more than four decades. However, interest in these proteins is rising due to the emergence of infectious diseases caused by new viruses and the difficulty in treating viral infections. On the other hand, there is a growing need to control crop diseases without resorting to the use of phytosanitary products which are very harmful to the environment and in this respect, RIPs have been shown as a promising tool that can be used to obtain transgenic plants resistant to viruses. The way in which RIPs exert their antiviral effect continues to be the subject of intense research and several mechanisms of action have been proposed. The purpose of this review is to examine the research studies that deal with this matter, placing special emphasis on the most recent findings.  相似文献   
50.
Diabetes leads to modification of collagen such as advanced glycation and cross-linking which play an important role in the pathogenesis of diabetes mellitus. We have investigated the effect of green tea on modification of collagen in streptozotocin (60 mg/kg body weight) induced diabetic rats. To investigate the therapeutic effect of green tea, treatment was begun six weeks after the onset of diabetes and green tea extract (300 mg/kg body weight) was given orally for 4 weeks. The collagen content, extent of advanced glycation, advanced glycation end products (AGE) and cross-linking of tail tendon collagen were investigated. Green tea reduced the tail tendon collagen content which increased in diabetic rats. Accelerated advanced glycation and AGE in diabetic animals, as detected by Ehrlich's-positive material and collagen linked fluorescence respectively were reduced significantly by green tea. The solubility of tail tendon collagen decreased significantly in diabetic rats indicating a remarkable increase in the cross-linking, whereas green tea increases the solubility of collagen in diabetic rats. The present study reveals that green tea is effective in reducing the modification of tail tendon collagen in diabetic rats. Thus green tea may have a therapeutic effect in the treatment of glycation induced complications of diabetes.  相似文献   
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