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   1279072篇
  免费   94449篇
  国内免费   2004篇
耳鼻咽喉   18207篇
儿科学   42371篇
妇产科学   38027篇
基础医学   187546篇
口腔科学   35514篇
临床医学   108416篇
内科学   252335篇
皮肤病学   26654篇
神经病学   99517篇
特种医学   50126篇
外国民族医学   366篇
外科学   198145篇
综合类   26529篇
现状与发展   1篇
一般理论   301篇
预防医学   92748篇
眼科学   29086篇
药学   98054篇
  1篇
中国医学   2503篇
肿瘤学   69078篇
  2018年   11910篇
  2015年   11691篇
  2014年   16111篇
  2013年   24489篇
  2012年   33797篇
  2011年   36133篇
  2010年   21324篇
  2009年   20151篇
  2008年   35196篇
  2007年   38137篇
  2006年   38686篇
  2005年   37984篇
  2004年   36597篇
  2003年   35538篇
  2002年   35084篇
  2001年   58197篇
  2000年   59713篇
  1999年   50791篇
  1998年   14278篇
  1997年   12844篇
  1996年   13117篇
  1995年   12371篇
  1994年   11785篇
  1993年   10893篇
  1992年   41058篇
  1991年   40431篇
  1990年   39953篇
  1989年   38770篇
  1988年   36164篇
  1987年   35393篇
  1986年   33772篇
  1985年   32174篇
  1984年   23954篇
  1983年   20854篇
  1982年   12393篇
  1981年   10942篇
  1980年   10211篇
  1979年   22648篇
  1978年   15887篇
  1977年   13738篇
  1976年   12979篇
  1975年   14226篇
  1974年   16700篇
  1973年   16094篇
  1972年   15332篇
  1971年   14244篇
  1970年   13226篇
  1969年   12741篇
  1968年   11987篇
  1967年   10491篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
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   
53.
54.
55.

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   
56.
57.
58.
59.
60.
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