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   1685431篇
  免费   116090篇
  国内免费   2420篇
耳鼻咽喉   23533篇
儿科学   55793篇
妇产科学   47852篇
基础医学   256818篇
口腔科学   45488篇
临床医学   146185篇
内科学   323963篇
皮肤病学   36125篇
神经病学   126178篇
特种医学   65446篇
外国民族医学   410篇
外科学   257887篇
综合类   32924篇
现状与发展   2篇
一般理论   403篇
预防医学   123897篇
眼科学   38992篇
药学   128833篇
  2篇
中国医学   3359篇
肿瘤学   89851篇
  2018年   16274篇
  2016年   13885篇
  2015年   15841篇
  2014年   21672篇
  2013年   32780篇
  2012年   45969篇
  2011年   49716篇
  2010年   29152篇
  2009年   27068篇
  2008年   47324篇
  2007年   51540篇
  2006年   51817篇
  2005年   50480篇
  2004年   48812篇
  2003年   47433篇
  2002年   46446篇
  2001年   74506篇
  2000年   76482篇
  1999年   64618篇
  1998年   18271篇
  1997年   16092篇
  1996年   16375篇
  1995年   15421篇
  1994年   14500篇
  1993年   13563篇
  1992年   51609篇
  1991年   51999篇
  1990年   51579篇
  1989年   50243篇
  1988年   46765篇
  1987年   45954篇
  1986年   43591篇
  1985年   41667篇
  1984年   31059篇
  1983年   26884篇
  1982年   15565篇
  1981年   13870篇
  1979年   29591篇
  1978年   20851篇
  1977年   17787篇
  1976年   17246篇
  1975年   19356篇
  1974年   22608篇
  1973年   21781篇
  1972年   20562篇
  1971年   19304篇
  1970年   18020篇
  1969年   17157篇
  1968年   16176篇
  1967年   14340篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
The aim of the present study was to evaluate the antimicrobial activity of two synbiotic combinations, Lactobacillus fermentum with short-chain fructooligosaccharides (FOS-LF) and Bifidobacterium longum with isomaltooligosaccharides (IMO-BL), against enterohaemorrhagic Escherichia coli O157:H7 and enteropathogenic E. coli O86. Antimicrobial activity was determined (1) by co-culturing the synbiotics and pathogens in batch cultures, and (2) with the three-stage continuous culture system (gut model), inoculated with faecal slurry from an elderly donor. In the co-culture experiments, IMO-BL was significantly inhibitory to both E. coli strains, while FOS-LF was slightly inhibitory or not inhibitory. Factors other than acid production appeared to play a role in the inhibition. In the gut models, both synbiotics effectively inhibited E. coli O157 in the first vessel, but not in vessels 2 and 3. E. coli O86 was not significantly inhibited.  相似文献   
72.
73.
74.

Background

Arterial vascular anomalies in patients undergoing kidney transplantation (KT) are correlated with a higher incidence of early surgical complications, potentially causing graft loss. Arterial reconstruction allows patients to overcome these surgical challenges, thus minimizing the risk of poor outcomes. The aim of the present study is to retrospectively investigate the safety and effectiveness of the multiple arterial reconstruction technique with a Teflon patch in case of an unavailable aortic patch: to do so, surgical complications, graft function, and patient survival were evaluated.

Methods

During the period January 2009 to August 2016, 202 adult deceased-donor KTs were performed at our center. Group A (n = 27; reconstruction of multiple arteries) and Group B (n = 175; control group) were compared.

Results

No differences were observed between the 2 groups in terms of early postoperative course, with no vascular complication observed in Group A. No vascular patch infections were reported, nor longer cold ischemia time rates. Similarly, long-term survival rates were similar between the 2 groups.

Conclusions

The Teflon-patch arterial reconstruction technique appears to be safe and effective, with an acceptable balance of benefits and potential risks of using a prosthetic material. Studies based on larger series are needed to further validate this approach.  相似文献   
75.
76.
77.
78.
79.
80.
BackgroundThe aim of this paper is to assess the current state of quality and outcomes measures being reported for hepatic resections in the recent literature.MethodsMedline and PubMed databases were searched for English language articles published between 1 January 2002 and 30 April 2013. Two examiners reviewed each article and relevant citations for appropriateness of inclusion, which excluded papers of liver donor hepatic resections, repeat hepatectomies or meta-analyses. Data were extracted and summarized by two examiners for analysis.ResultsFifty-five studies were identified with suitable reporting to assess peri-operative mortality in hepatic resections. In only 35% (19/55) of the studies was the follow-up time explicitly stated, and in 47% (26/55) of studies peri-operative mortality was limited to in-hospital or 30 days. The time period in which complications were captured was not explicitly stated in 19 out of 28 studies. The remaining studies only captured complications within 30 days of the index operation (8/28). There was a paucity of quality literature addressing truly patient-centred outcomes.ConclusionQuality outcomes after a hepatic resection are inconsistently reported in the literature. Quality outcome studies for a hepatectomy should report mortality and morbidity at a minimum of 90 days after surgery.  相似文献   
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