首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   109088篇
  免费   9090篇
  国内免费   5715篇
耳鼻咽喉   1383篇
儿科学   1232篇
妇产科学   1581篇
基础医学   14973篇
口腔科学   2213篇
临床医学   13365篇
内科学   17508篇
皮肤病学   2063篇
神经病学   6573篇
特种医学   4672篇
外国民族医学   53篇
外科学   11996篇
综合类   10912篇
现状与发展   24篇
一般理论   28篇
预防医学   6190篇
眼科学   3506篇
药学   11010篇
  67篇
中国医学   4565篇
肿瘤学   9979篇
  2024年   283篇
  2023年   1428篇
  2022年   3890篇
  2021年   5163篇
  2020年   3569篇
  2019年   3652篇
  2018年   3959篇
  2017年   3266篇
  2016年   3704篇
  2015年   5241篇
  2014年   6220篇
  2013年   5928篇
  2012年   8776篇
  2011年   8981篇
  2010年   5518篇
  2009年   4232篇
  2008年   5870篇
  2007年   5549篇
  2006年   5436篇
  2005年   5197篇
  2004年   3693篇
  2003年   3339篇
  2002年   2765篇
  2001年   2195篇
  2000年   2163篇
  1999年   2356篇
  1998年   1440篇
  1997年   1389篇
  1996年   1040篇
  1995年   971篇
  1994年   840篇
  1993年   548篇
  1992年   707篇
  1991年   629篇
  1990年   583篇
  1989年   510篇
  1988年   458篇
  1987年   377篇
  1986年   326篇
  1985年   272篇
  1984年   173篇
  1983年   124篇
  1982年   69篇
  1981年   77篇
  1980年   52篇
  1979年   115篇
  1978年   59篇
  1975年   63篇
  1974年   56篇
  1971年   61篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
M Y Fan  Z P Lum  X W Fu  L Levesque  I T Tai  A M Sun 《Diabetes》1990,39(4):519-522
Prolonged survival of pancreatic islet allografts implanted in diabetic BB rats was achieved by encapsulation of individual islets in a protective biocompatible alginate-polylysine-alginate membrane without immunosuppression. Intraperitoneal transplantation of the encapsulated islets reversed the diabetic state of the recipients within 3 days and maintained normoglycemia for 190 days. Normal body weight and urine volume were maintained during this period, and no cataracts were detected in the transplant recipients. In contrast, control rats receiving transplants of unencapsulated islets experienced normoglycemia for less than 2 wk. These results demonstrated that microencapsulation can protect allografted islets from both graft rejection and autoimmune destruction without immunosuppression in an animal model that mimics human insulin-dependent diabetes.  相似文献   
12.
目的:探讨EB病毒感染与人大肠癌发生的关系。方法:用原位分子杂交法对130例人大肠癌标本中EB病毒小分子RNA片段进行检测。结果:130例标本中有6例(4.48%)癌组织呈阳性反应,其中4例为男性,4例有明显淋巴细胞浸润。结论:EB病毒感染可能与我国部分大肠腺癌的发生有关,肿瘤细胞间质中大量淋巴细胞浸润可能是EB病毒感染的重要病理学特征。  相似文献   
13.
为观察高渗盐水硬膜外注射术后镇痛效果,用双盲法对60例病人进行了研究。生理盐水对照级术后镇痛优良率为3.33%,镇痛有效率为10%,均需用镇痛药;高渗盐水组术后镇痛优良率为86.67%,有效率为96.67%,很少使用镇痛药。两组差别显著(P<0.05,P<0.01)。对其他感觉和运动功能无明显影响。高渗盐水组与吗啡组比较镇痛效果相同(P>0.05),副作用少(P<0.01)。说明硬膜外高渗氯化钠溶液是一种安全有效的镇痛方法,有较高推广应用价值。  相似文献   
14.
This study was conducted to investigate the hypocholesterolemic effect of simvastatin (30 mg/kg BW) and antioxidant effect of coenzyme Q10 (CoQ10, 15 mg/kg BW) or green tea (5%) on erythrocyte Na leak, platelet aggregation and TBARS production in hypercholesterolemic rats treated with statin. Food efficiency ratio (FER, ADG/ADFI) was decreased in statin group and increased in green tea group, and the difference between these two groups was significant (p<0.05). Plasma total cholesterol was somewhat increased in all groups with statin compared with control. Plasma triglyceride was decreased in statin group and increased in groups of CoQ10 and green tea, and the difference between groups of statin and green tea was significant (p<0.05). Liver total cholesterol was not different between the control and statin group, but was significantly decreased in the group with green tea compared with other groups (p<0.05). Liver triglyceride was decreased in groups of statin and green tea compared with the control, and the difference between groups of the control and green tea was significant (p<0.05). Platelet aggregation of both the initial slope and the maximum was not significantly different, but the group with green tea tended to be higher in initial slope and lower in the maximum. Intracellular Na of group with green tea was significantly higher than the control or statin group (p<0.05). Na leak in intact cells was significantly decreased in the statin group compared with the control (p<0.05). Na leak in AAPH treated cells was also significantly reduced in the statin group compared with groups of the control and CoQ10 (p<0.05). TBARS production in platelet rich plasma was significantly decreased in the groups with CoQ10 and green tea compared with the control and statin groups (p<0.05). TBARS of liver was significantly decreased in the group with green tea compared with the statin group (p<0.05). In the present study, even a high dose of statin did not show a cholesterol lowering effect, therefore depletion of CoQ10 following statin treatment in rats is not clear. More clinical studies are needed for therapeutic use of CoQ10 as an antioxidant in prevention of degenerative diseases independent of statin therapy.  相似文献   
15.
16.
报告12例疸性腔皮病患者的性别与年龄构成、并发症、实验室检查、治疗经过和结果,对该病的病因、治疗和预后进行了讨论。  相似文献   
17.
Critical size defect in the canine mandible.   总被引:3,自引:0,他引:3  
OBJECTIVE: The purpose of this study was to determine the minimum size defect in a canine mandible that would not spontaneously heal during the dog's natural life (the critical size defect). STUDY DESIGN: Sixteen adult female mongrel dogs underwent continuity resection on both sides of the mandible to create bilateral defects. In 8 dogs, mandibular defects ranging from 5 to 20 mm were created with periosteal resection. In the other 8 dogs, mandibular defects ranging from 30 to 60 mm were created preserving the periosteum. The dogs were then killed at 6 months and the defects examined using radiographs and histologic analysis. RESULTS: When the periosteum was removed, mandibular defects greater than 15 mm failed to heal across the entire defect. However, when the periosteum was preserved, mandibular defects needed to be greater than 50 mm in order to fail to heal. CONCLUSION: The critical size defect in a canine mandible model is 15 mm when the periosteum is removed and 50 mm when the periosteum is preserved.  相似文献   
18.
难治性气管异物的处理   总被引:1,自引:0,他引:1  
目的 探讨难治性气管异物的处理方法。方法 回顾 1994~ 2 0 0 3年 10年内收治的 12 5 8例气管异物中 ,10 9例难治性气管异物 (塑料笔帽、鸡骨头、图钉、钢珠、苍耳子球、玩具、带壳花生米、气门芯等 )的处理过程。患者年龄最小的为 8个月 ,最大的为 43岁。异物史最长达 12年。结果  89例难治性气管异物直接从支气管镜下取出 ,19例行气管切开 ,1例气门芯异物开胸取出。结论 在处理难治性气管异物时要做好充分的术前准备 ,正确判断和处理并发症。  相似文献   
19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号