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   1494010篇
  免费   101212篇
  国内免费   2636篇
耳鼻咽喉   21316篇
儿科学   49645篇
妇产科学   43807篇
基础医学   214521篇
口腔科学   41509篇
临床医学   126797篇
内科学   291988篇
皮肤病学   31391篇
神经病学   114893篇
特种医学   60887篇
外国民族医学   462篇
外科学   231103篇
综合类   28170篇
现状与发展   1篇
一般理论   374篇
预防医学   110595篇
眼科学   34081篇
药学   112417篇
  5篇
中国医学   2657篇
肿瘤学   81239篇
  2018年   16372篇
  2017年   13503篇
  2016年   14030篇
  2015年   17105篇
  2014年   21543篇
  2013年   29869篇
  2012年   46081篇
  2011年   44348篇
  2010年   25548篇
  2009年   25632篇
  2008年   40677篇
  2007年   44422篇
  2006年   45092篇
  2005年   51824篇
  2004年   51631篇
  2003年   46355篇
  2002年   41184篇
  2001年   61968篇
  2000年   61418篇
  1999年   55576篇
  1998年   15369篇
  1997年   13595篇
  1996年   13890篇
  1995年   13154篇
  1994年   12456篇
  1992年   46633篇
  1991年   46123篇
  1990年   45783篇
  1989年   44342篇
  1988年   41340篇
  1987年   40426篇
  1986年   38502篇
  1985年   36475篇
  1984年   26978篇
  1983年   23353篇
  1982年   13506篇
  1981年   11876篇
  1979年   25833篇
  1978年   17939篇
  1977年   15293篇
  1976年   14309篇
  1975年   16210篇
  1974年   19251篇
  1973年   18375篇
  1972年   17580篇
  1971年   16437篇
  1970年   15338篇
  1969年   14798篇
  1968年   13822篇
  1967年   12300篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
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   
63.
64.
65.

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   
66.
67.
68.
69.
70.
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