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   510487篇
  免费   295146篇
  国内免费   51265篇
耳鼻咽喉   4849篇
儿科学   7438篇
妇产科学   7462篇
基础医学   119326篇
口腔科学   7202篇
临床医学   92800篇
内科学   135790篇
皮肤病学   7786篇
神经病学   35606篇
特种医学   17890篇
外国民族医学   111篇
外科学   70306篇
综合类   90129篇
现状与发展   62篇
一般理论   53篇
预防医学   57571篇
眼科学   23983篇
药学   83368篇
  192篇
中国医学   57781篇
肿瘤学   37193篇
  2023年   5900篇
  2022年   12739篇
  2021年   15853篇
  2020年   15024篇
  2019年   21007篇
  2018年   22100篇
  2017年   21676篇
  2016年   19915篇
  2015年   23509篇
  2014年   26083篇
  2013年   25295篇
  2012年   31628篇
  2011年   34953篇
  2010年   29123篇
  2009年   34306篇
  2008年   25757篇
  2007年   22665篇
  2006年   21790篇
  2005年   21717篇
  2004年   19489篇
  2003年   17955篇
  2002年   17032篇
  2001年   18182篇
  2000年   13799篇
  1999年   19251篇
  1998年   17669篇
  1997年   17563篇
  1996年   17579篇
  1995年   17580篇
  1994年   17016篇
  1993年   14891篇
  1992年   15115篇
  1991年   14093篇
  1990年   12791篇
  1989年   12404篇
  1988年   11747篇
  1987年   11053篇
  1986年   10331篇
  1985年   9234篇
  1984年   7039篇
  1983年   6920篇
  1982年   7812篇
  1981年   7296篇
  1980年   6959篇
  1979年   6853篇
  1978年   5945篇
  1977年   6213篇
  1976年   5830篇
  1975年   5553篇
  1974年   5139篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
Volume and profile of alcohol consumption among students and classmates as predictors of aggression and victimization: a multilevel analysis among Swiss adolescents

Objective:  

To test the effects of the volume of alcohol consumption and drinking patterns on alcohol-related aggression and victimization, both at the individual and class levels.  相似文献   
32.
33.
OBJECTIVE: It is well documented that cardiopulmonary bypass (CPB) severely impairs cellular immunity. The objective of this study was to investigate the effect of prostaglandin E1 (PGE1) on cellular immunity after CPB. METHODS: Patients who underwent elective cardiac surgery were randomly divided into the PGE1 group (n=12) and the control group (n=12). In the PGE1 group, PGE1 was administered at 20 ng/kg/min from just after the induction of anesthesia to the end of surgery. Peripheral blood mononuclear cells (PBMCs) were taken before anesthesia and on postoperative days 1, 3 and 7 (POD 1, POD 3 and POD 7). Proliferation responses of T cells to phytohemagglutinin (PHA) and pure protein derivative (PPD) antigen were measured as indicators of cellular immunity. RESULTS: PGE1 significantly attenuated the impairment of both PHA and PPD response after cardiac surgery on POD 1 (PHA response, 30 +/- 21% vs. 53 +/- 32%, control vs. PGE, p=0.048; PPD response, 18 +/- 21% vs. 39 +/- 27%, control vs. PGE, p=0.046). The reduced glutathione content of PBMCs in the control group was significantly decreased on POD 1. CONCLUSION: PGE1 attenuated the impairment of cellular immunity after cardiac surgery with CPB by reducing oxidative stress on PBMCs.  相似文献   
34.
35.
36.
37.
Finding appropriate soft-tissue to cover a wound located over the middle or distal portion of the foot can be challenging. A distally based sural fasciomusculocutaneous flap including the sural nerve and a midline cuff of the gastrocnemius muscle can be used for this purpose. This flap is designed on the proximal third of the posterior calf and is nourished in a retrograde manner by the lower peroneal septocutaneous perforators, through the vascular axis of the sural nerve to the musculocutaneous perforators of the gastrocnemius muscle. Between October of 2002 and January of 2004, this flap was applied in nine individuals, including four diabetic patients. The skin defects all resulted from trauma, osteomyelitis or chronic ulcer, and combined with bone or tendon exposure. One flap developed distal necrosis. The other flaps survived fully and provided good contour. In our series, diabetes mellitus seemed not to compromise the vascularity of the flap. The distally based sural fasciomusculocutaneous flap is very useful for lower limb reconstruction, particularly for the foot, because of its long vascular pedicle and the availability of the skin portion of the proximal calf based on direct branches between the musculocutaneous perforators and the neurovascular axis of the sural nerve. This is an important variant of the sural neurocutaneous flap and it appears to be a good alternative to free flaps for resurfacing the foot.  相似文献   
38.
在颈椎前路减压、植骨、带锁钢板内固定技术日渐成熟的今天,越来越多的医院开展了该项手术。自1998年2月-2005年8月应用该方法治疗颈椎病215例,发生与内置物钢板及钛网相关的并发症14例,为此积累了一定的经验,现总结如下。1临床资料本组215例,男126例,女89例;年龄42~82岁,平均  相似文献   
39.
We report the case of a 4-year-old girl who had quadricuspid aortic valve regurgitation with tetralogy of Fallot and pulmonary atresia. This combination is very uncommon. Aortic valve replacement was performed successfully due to aortic regurgitation which had progressed one year after the total repair. The dilated aortic annulus plus quadricuspid aortic valve may result in progressive aortic regurgitation for a short period.  相似文献   
40.
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