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101.
环孢素A体外抗曼氏血吸虫作用的观察 总被引:1,自引:0,他引:1
MF1小鼠实验感染曼氏血吸虫尾蚴1周、3周和6周后,分别经肺静脉和门静脉灌注取虫。实验显示,药物体外抗曼氏血吸虫的作用呈时间、剂量和虫龄依赖方式,童虫和雄虫对药物更敏感。 相似文献
102.
Intravenously injected polystyrene microspheres with functional amino groups (AP-MSs, 0.2,1.0, and 4.0 urn in diameter) were cleared from the blood very rapidly. The calculated half-lives for 0.2-, 1.0-, and 4.0-μm AP-MSs were about 55,60, and 50s; no significant differences were found with 106,107, and 108 microspheres/rat. Loading experiments showed that the liver, spleen, lung, kidney, and heart had a very high capacity to take up AP-MSs. The AP-MSs were distributed mainly to the liver, lung, and spleen, whereas other organs contained less than 1 % of injected AP-MSs. In terms of numbers of AP-MSs per gram of tissue, the highest contents were found in spleen, liver, and lung for 0.2-, 1.0-, and 4.0-um AP-MSs, respectively. There was indication of redistribution of particles from one organ to another during the first 6 h after injection. Chondroitin sulfate A (Chon) and hyaluronic acid (Hya) adsorbed or covalently linked to AP-MSs increased uptake in the liver, with Chon AP-MSs (adsorbed or linked) showing the best effect: about 25% increase compared with unadsorbed 1-μm AP-MSs. Experiments with separated cells in vitro demonstrated that 1 um AP-MSs, intravenously injected, associated only with Kupffer cells. When the microspheres were adsorbed with Chon, there was also association with liver endothelial cells. This finding indicates that conjugation of microspheres with ligands for endothelial receptors may be a useful method for directing microspheres to specific organs, even if the receptors are not by themselves phagocytic 相似文献
103.
104.
[目的]了解泰州市市级各医院的消毒剂使用现状,为指导临床合理、规范使用消毒剂提供依据和指南。[方法]以泰州市5所市级医院为研究对象,全面调查临床使用消毒剂的种类及其使用中消毒剂的有效成份、年消耗量、消毒方法知晓率、染菌量等背景资料。[结果]5所医院使用的消毒剂种类基本相似,主要是含氯消毒剂等高中水平消毒剂,低水平消毒剂使用量很少,消毒剂年消耗量巨大。医院工作人员消毒知识知晓率低,消毒剂使用不合理,影响消毒效果。使用中消毒剂检测合格率为51.4%;其中消毒剂有效成份合格率71.2%;染菌量指标合格率90.9%。消毒剂染菌量合格率与消毒剂配制浓度、消毒时间、消毒方法知晓率之间呈正相关,相关密切程度:消毒时间〉消毒方法〉消毒剂配制浓度;消毒剂总合格率与消毒剂有效成份合格率之间呈正相关。[结论]医院消毒剂使用不合理,可致医院菌株对常用消毒剂产生抗药性。 相似文献
105.
106.
顺铂对结直肠癌肿瘤浸润淋巴细胞杀伤活性的影响 总被引:1,自引:0,他引:1
为在临床选择有效的免疫化疗方案提供一定的理论依据,作者以结直肠癌肿瘤浸润淋巴细胞(TIL)和顺铂(CDDP)为研究对象,对16名手术治疗的结直肠癌患者,分别观察CDDP体内注射及体外预处理TIL和Raji细胞对TIL表面标志和杀伤活性的影响。流式细胞仪检测结果显示,静脉注射CDDP能增加结直肠癌TIL中CD3+/CD4+和CD3+/CD8+细胞含量,同时增强TIL体外杀伤Raji细胞的活性;而体外以CDDP处理Raji细胞能增强其对结直肠癌TIL杀伤的敏感性。作者认为,对于联合应用TIL和CDDP治疗结直肠癌的临床效果有必要进一步研究。 相似文献
107.
108.
J. D. Kakisis F. Abir C. D. Liapis B. E. Sumpio 《European journal of vascular and endovascular surgery》2003,25(6):493-504
OBJECTIVES: to summarize existing evidence regarding the benefits and the risks of all available interventional and medical means aimed at cardiac risk reduction in patients undergoing vascular surgery. DESIGN: review of the literature. MATERIALS AND METHODS: a critical review of all studies examining the impact of various prophylactic cardiac maneuvers on perioperative outcome following vascular surgery was performed. Overall mortality, cardiac mortality and myocardial infarction rate were used as the outcome measures. RESULTS: coronary artery bypass grafting is associated with a 60% decrease in perioperative mortality in patients undergoing vascular surgery, but in most of the cases this decrease does not outweigh the combined risk of the cardiac and the subsequent noncardiac vascular procedure. Data supporting the cardioprotective effect of percutaneous transluminal angioplasty in the perioperative setting are insufficient. beta-blockade has been shown to decrease perioperative mortality and cardiac morbidity in both high-risk (strong evidence) and low-risk (weak evidence) patients. CONCLUSIONS: coronary revascularization is rarely indicated to simply get the patient through vascular surgery and should be reserved for patients who would need it irrespective of the scheduled vascular procedure. Among all available pharmacological agents, including beta-blockers, alpha-agonists, calcium channel blockers and nitrates, only beta-blockers have been proven to reduce the cardiac risk of vascular surgery. 相似文献
109.
Acute toxicity of two pyrethroids,permethrin, and cypermethrin in neonatal and adult rats 总被引:2,自引:0,他引:2
Franco Cantalamessa 《Archives of toxicology》1993,67(7):510-513
The present study aims specifically at obtaining a comparison of the acute toxicity of cypermethrin (CY), a type I pyrethroid, and permethrin (PERM), a type II pyrethroid, administered orally as a single dose to neonatal and adult rats, and at assessing the importance of pyrethroid biotransformation in CY and PERM toxicity through use of drug metabolism inhibitors. Our experiments show that CY is more toxic than PERM to adult and neonatal rats. The sensitivity of neonatal rats both to CY and to PERM toxicity is higher, the younger the animals. CY is much more toxic than PERM in the neonatal rat, compared with the adult. In rats aged 8, 16, and 21 days, pretreatment with piperonil butoxide (PB), a monooxygenase inhibitor, or with tri-o-tolyl phosphate (TOTP), an esterase inhibitor, does not produce significant variations in the lethal effects of CY and PERM. Instead, in the adult rats, a significant increase in CY (X2=5.97;p<0.05) and PERM (X2=4.37;p<0.05) mortality occurred in rats pretreated with esterase inhibitors, whereas no increase in CY and PERM toxicity was found in adult animals pretreated with monooxygenase inhibitor. It was concluded that the higher level of sensitivity of the neonate rat to pyrethroid toxicity is probably due to incomplete development of the enzymes which catalyze the metabolism of pyrethroids in the liver of young animals. It is suggested that ester hydrolysis is an important pyrethroids detoxification reaction in the adult rat. 相似文献
110.
The effect of the proton pump inhibitor omeprazole on the anticoagulation and the pharmacokinetics of warfarin enantiomers was studied in rats. Omeprazole given intraperitoneally in a daily dose of 0.67 mg/kg over 8 days had no significant effect on the absorption, distribution and the total serum clearance values of the S- and R-enantiomers of warfarin. Omeprazole did not affect the pre-treatment baseline blood coagulation and the in vitro rat serum protein binding of warfarin enantiomers. In vitro study with rat liver microsomes showed that omeprazole had an inhibitory effect on the hydroxylation of warfarin enantiomers. Results obtained from in vivo urinary excretion study revealed that omeprazole inhibited the formation clearance of both S- and R-form oxidative metabolites, but increased that of the overall reductive metabolites, and the renal clearance of S- and R-enantiomers, of warfarin. As a consequence, the total serum clearance values for warfarin enantiomers remained unchanged and the hypoprothrombinaemic response produced by warfarin was not affected. 相似文献