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   1262663篇
  免费   96449篇
  国内免费   1579篇
耳鼻咽喉   16320篇
儿科学   41005篇
妇产科学   34951篇
基础医学   189504篇
口腔科学   34740篇
临床医学   117783篇
内科学   247850篇
皮肤病学   27319篇
神经病学   101885篇
特种医学   46781篇
外国民族医学   265篇
外科学   178639篇
综合类   25756篇
现状与发展   3篇
一般理论   568篇
预防医学   104677篇
眼科学   28053篇
药学   92589篇
  6篇
中国医学   2022篇
肿瘤学   69975篇
  2018年   13537篇
  2017年   10399篇
  2016年   11343篇
  2015年   13088篇
  2014年   18015篇
  2013年   27504篇
  2012年   37609篇
  2011年   40003篇
  2010年   23075篇
  2009年   22271篇
  2008年   37778篇
  2007年   40405篇
  2006年   39984篇
  2005年   39109篇
  2004年   37559篇
  2003年   35973篇
  2002年   34876篇
  2001年   56045篇
  2000年   57053篇
  1999年   48103篇
  1998年   13401篇
  1997年   12225篇
  1996年   12645篇
  1995年   11915篇
  1994年   11108篇
  1993年   10401篇
  1992年   38201篇
  1991年   37683篇
  1990年   36449篇
  1989年   35263篇
  1988年   32694篇
  1987年   32032篇
  1986年   30527篇
  1985年   28796篇
  1984年   21944篇
  1983年   19197篇
  1982年   11364篇
  1981年   10325篇
  1979年   20947篇
  1978年   15398篇
  1977年   12791篇
  1976年   11849篇
  1975年   12816篇
  1974年   15594篇
  1973年   15365篇
  1972年   14514篇
  1971年   13553篇
  1970年   12788篇
  1969年   12068篇
  1968年   11231篇
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
71.
72.
73.
74.
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   
75.
76.

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   
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