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   921615篇
  免费   63803篇
  国内免费   2407篇
耳鼻咽喉   12662篇
儿科学   29200篇
妇产科学   26546篇
基础医学   129496篇
口腔科学   25041篇
临床医学   77107篇
内科学   187618篇
皮肤病学   19247篇
神经病学   73709篇
特种医学   37133篇
外国民族医学   336篇
外科学   145003篇
综合类   19358篇
一般理论   278篇
预防医学   66811篇
眼科学   20598篇
药学   65247篇
  1篇
中国医学   1844篇
肿瘤学   50590篇
  2018年   9535篇
  2017年   7536篇
  2016年   8088篇
  2015年   9251篇
  2014年   13007篇
  2013年   20203篇
  2012年   27080篇
  2011年   28716篇
  2010年   17372篇
  2009年   16535篇
  2008年   27383篇
  2007年   29162篇
  2006年   29339篇
  2005年   28896篇
  2004年   27575篇
  2003年   26750篇
  2002年   26285篇
  2001年   41568篇
  2000年   42740篇
  1999年   36503篇
  1998年   10202篇
  1997年   9392篇
  1996年   9245篇
  1995年   8619篇
  1994年   8250篇
  1993年   7754篇
  1992年   28342篇
  1991年   27101篇
  1990年   26532篇
  1989年   25482篇
  1988年   23702篇
  1987年   23283篇
  1986年   22375篇
  1985年   21264篇
  1984年   15944篇
  1983年   13631篇
  1982年   8229篇
  1981年   7190篇
  1979年   14664篇
  1978年   10289篇
  1977年   8710篇
  1976年   8204篇
  1975年   9012篇
  1974年   10763篇
  1973年   10232篇
  1972年   9695篇
  1971年   8947篇
  1970年   8616篇
  1969年   8038篇
  1968年   7703篇
排序方式: 共有10000条查询结果,搜索用时 15 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