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   903351篇
  免费   62599篇
  国内免费   2348篇
耳鼻咽喉   12515篇
儿科学   28798篇
妇产科学   26223篇
基础医学   127100篇
口腔科学   24755篇
临床医学   75084篇
内科学   183920篇
皮肤病学   19139篇
神经病学   71734篇
特种医学   36522篇
外国民族医学   336篇
外科学   142697篇
综合类   19044篇
一般理论   247篇
预防医学   64898篇
眼科学   20132篇
药学   64015篇
中国医学   1802篇
肿瘤学   49337篇
  2018年   9174篇
  2017年   7247篇
  2016年   7757篇
  2015年   8821篇
  2014年   12511篇
  2013年   19372篇
  2012年   25889篇
  2011年   27493篇
  2010年   16695篇
  2009年   15900篇
  2008年   26303篇
  2007年   27919篇
  2006年   28083篇
  2005年   27632篇
  2004年   26451篇
  2003年   25626篇
  2002年   25192篇
  2001年   41450篇
  2000年   42648篇
  1999年   36341篇
  1998年   10003篇
  1997年   9179篇
  1996年   9107篇
  1995年   8472篇
  1994年   8115篇
  1993年   7605篇
  1992年   28255篇
  1991年   27037篇
  1990年   26459篇
  1989年   25385篇
  1988年   23595篇
  1987年   23211篇
  1986年   22285篇
  1985年   21182篇
  1984年   15831篇
  1983年   13499篇
  1982年   8103篇
  1979年   14603篇
  1978年   10221篇
  1977年   8640篇
  1976年   8156篇
  1975年   8971篇
  1974年   10705篇
  1973年   10193篇
  1972年   9677篇
  1971年   8922篇
  1970年   8588篇
  1969年   8029篇
  1968年   7688篇
  1967年   7089篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
Graefe's Archive for Clinical and Experimental Ophthalmology - The published online version contains mistake as the author's first name and last name have been interchanged as "Hild...  相似文献   
2.
BACKGROUND The adenoma detection rate(ADR) is inversely associated with the incidence of interval colorectal cancer and serves as a benchmark quality criterion during screening colonoscopy. However, adenoma miss rates reach up to 26% and studies have shown that a second inspection of the right colon in retroflected view(RFV) can increase ADR.AIM To assess whether inspection of the whole colon in RFV compared to standard forward view(SFV) can increase ADR.METHODS Patients presenting for screening or surveillance colonoscopy were invited to participate in this randomized controlled trial and randomized into two arms. In RFV arm colonoscopy was initially performed with SFV, followed by a second inspection of the whole colon in RFV. In the SFV arm first withdrawal was performed with SFV, followed by a second inspection of the whole colon again with SFV. Number, size and morphology of polyps found during first and second inspection in each colonic segment were recorded and all polyps were removed and sent for histopathology in separate containers.RESULTS Two hundred and five patients were randomly assigned to the RFV(n = 101) and SFV(n = 104) arm. In the RFV arm, both polyp detection rate(PDR) and ADR were increased under second inspection in RFV(PDR 1~(st) SFV: 39.8%, PDR 2~(nd)RFV: 46.6%; ADR 1~(st) SFV: 35.2%, ADR 2~(nd) RFV: 42%). Likewise, in the SFV arm,PDR and ADR were increased under second inspection(PDR 1~(st) SFV: 37.5%, PDR 2~(nd) SFV: 46.6%; ADR 1~(st) SFV: 34.1%, ADR 2~(nd)SFV: 44.3%) with no significant differences in ADR and PDR between the SFV and RFV arm. Mean number of adenomas per patient(APP) was increased in the RFV and SFV(APP RFV arm: 1~(st) SFV: 1.71; 2~(nd) RFV: 2.38; APP SFV arm: 1~(st) SFV: 1.83, 2~(nd)SFV:2.2). The majority of adenomas additionally found during second inspection in RFV or in SFV were located in the transverse and left-sided colon and were 5 mm in size.CONCLUSION Second inspection of the whole colon leads to increased adenoma detection with no differences between SFV and RFV. Hence, increased detection is most likely a feature of the second inspection itself but not of the inspection mode.  相似文献   
3.
4.
Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning.  相似文献   
5.
6.
7.
8.
9.
10.
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