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   899881篇
  免费   62274篇
  国内免费   2333篇
耳鼻咽喉   12474篇
儿科学   28680篇
妇产科学   26144篇
基础医学   126592篇
口腔科学   24686篇
临床医学   74765篇
内科学   183155篇
皮肤病学   18984篇
神经病学   71413篇
特种医学   36489篇
外国民族医学   336篇
外科学   142133篇
综合类   19031篇
一般理论   247篇
预防医学   64567篇
眼科学   20083篇
药学   63809篇
中国医学   1798篇
肿瘤学   49102篇
  2018年   9049篇
  2017年   7160篇
  2016年   7674篇
  2015年   8722篇
  2014年   12369篇
  2013年   19211篇
  2012年   25655篇
  2011年   27261篇
  2010年   16575篇
  2009年   15780篇
  2008年   26128篇
  2007年   27737篇
  2006年   27920篇
  2005年   27448篇
  2004年   26292篇
  2003年   25465篇
  2002年   25056篇
  2001年   41361篇
  2000年   42556篇
  1999年   36271篇
  1998年   9969篇
  1997年   9149篇
  1996年   9084篇
  1995年   8448篇
  1994年   8082篇
  1993年   7584篇
  1992年   28205篇
  1991年   26989篇
  1990年   26410篇
  1989年   25351篇
  1988年   23557篇
  1987年   23175篇
  1986年   22253篇
  1985年   21156篇
  1984年   15812篇
  1983年   13480篇
  1982年   8094篇
  1979年   14595篇
  1978年   10211篇
  1977年   8635篇
  1976年   8148篇
  1975年   8963篇
  1974年   10698篇
  1973年   10185篇
  1972年   9664篇
  1971年   8917篇
  1970年   8584篇
  1969年   8025篇
  1968年   7684篇
  1967年   7087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