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   1398747篇
  免费   99146篇
  国内免费   2229篇
耳鼻咽喉   20353篇
儿科学   46460篇
妇产科学   40877篇
基础医学   205092篇
口腔科学   38731篇
临床医学   117585篇
内科学   273035篇
皮肤病学   29708篇
神经病学   111219篇
特种医学   56517篇
外国民族医学   390篇
外科学   217973篇
综合类   27293篇
现状与发展   1篇
一般理论   334篇
预防医学   98585篇
眼科学   32235篇
药学   106440篇
  1篇
中国医学   2762篇
肿瘤学   74531篇
  2018年   13905篇
  2016年   12492篇
  2015年   14314篇
  2014年   18819篇
  2013年   28311篇
  2012年   39746篇
  2011年   41720篇
  2010年   24681篇
  2009年   22866篇
  2008年   40767篇
  2007年   44268篇
  2006年   44885篇
  2005年   44354篇
  2004年   42546篇
  2003年   41598篇
  2002年   40983篇
  2001年   62246篇
  2000年   63741篇
  1999年   54239篇
  1998年   15325篇
  1997年   13710篇
  1996年   13751篇
  1995年   12901篇
  1994年   12278篇
  1993年   11352篇
  1992年   42583篇
  1991年   41942篇
  1990年   41445篇
  1989年   40142篇
  1988年   37317篇
  1987年   36568篇
  1986年   34865篇
  1985年   33264篇
  1984年   24801篇
  1983年   21499篇
  1982年   12861篇
  1981年   11365篇
  1979年   23576篇
  1978年   16566篇
  1977年   14333篇
  1976年   13494篇
  1975年   14969篇
  1974年   17480篇
  1973年   16801篇
  1972年   16054篇
  1971年   14920篇
  1970年   13828篇
  1969年   13312篇
  1968年   12553篇
  1967年   11003篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
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   
62.
63.
64.

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   
65.
66.
67.
68.
69.
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   
70.
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