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   2029138篇
  免费   146703篇
  国内免费   2785篇
耳鼻咽喉   27622篇
儿科学   60719篇
妇产科学   54400篇
基础医学   296172篇
口腔科学   58995篇
临床医学   184310篇
内科学   394741篇
皮肤病学   43076篇
神经病学   160597篇
特种医学   77207篇
外国民族医学   339篇
外科学   304754篇
综合类   41065篇
现状与发展   3篇
一般理论   776篇
预防医学   155275篇
眼科学   46254篇
药学   152882篇
  9篇
中国医学   3916篇
肿瘤学   115514篇
  2018年   20482篇
  2017年   15819篇
  2016年   17390篇
  2015年   20031篇
  2014年   27547篇
  2013年   41587篇
  2012年   56656篇
  2011年   59973篇
  2010年   35071篇
  2009年   33722篇
  2008年   57498篇
  2007年   60915篇
  2006年   61428篇
  2005年   59669篇
  2004年   57450篇
  2003年   55130篇
  2002年   53773篇
  2001年   100051篇
  2000年   102627篇
  1999年   86323篇
  1998年   22366篇
  1997年   20003篇
  1996年   20439篇
  1995年   19120篇
  1994年   17801篇
  1993年   16557篇
  1992年   67347篇
  1991年   65447篇
  1990年   63438篇
  1989年   61661篇
  1988年   56829篇
  1987年   55482篇
  1986年   52352篇
  1985年   49580篇
  1984年   36759篇
  1983年   31724篇
  1982年   17882篇
  1981年   15898篇
  1979年   34105篇
  1978年   24183篇
  1977年   20387篇
  1976年   18398篇
  1975年   20109篇
  1974年   24489篇
  1973年   23659篇
  1972年   22464篇
  1971年   21103篇
  1970年   19989篇
  1969年   18928篇
  1968年   17470篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Academic output is just one aspect of a successful career as a plastic surgeon. However, for those with a strong interest in academia, the academic output of a department will likely be a key factor when deciding how to rank jobs. The aim of this study was to quantify and rank the academic output of plastic surgery units across the UK and Ireland. The Institute for Scientific Information (ISI) Web of Science Bibliometric analysis tool was used to collate cumulative (1950–2016), 10 year (2006–2016) and 3 years (2013–2015) research output data for plastic surgery units in the UK and Ireland. Sixty-six plastic surgery units were identified. Departments were ranked for each time period according to the number of papers produced, number of citations (Nc) and h-index (a measure of the impact of scientific output). The top 3 departments for number of papers in the last 10 years were The Royal Free Hospital, London (226) Broomfield Hospital, Chelmsford (218), and Morriston Hospital and Swansea (188). The top 3 for h-number were The Royal Free Hospital (21) Wythenshawe Hospital, Manchester (18) and Morriston Hospital (17). Academic output varies across plastic surgery units in the UK and Ireland. A number of departments have consistently maintained high academic outputs across the years and will be of interest to surgeons hoping to pursue a career in academia.  相似文献   
3.
4.
Pharmaceutical Chemistry Journal - An HPLC-MS method for simultaneous quantitative determination of a novel gestagenic pharmaceutical and two of its metabolites in rat and rabbit blood sera was...  相似文献   
5.

Objectives

Expedient extubation after cardiac surgery has been associated with improved outcomes, leading to postoperative extubation frequently during overnight hours. However, recent evidence in a mixed medical-surgical intensive care unit population demonstrated worse outcomes with overnight extubation. This study investigated the impact of overnight extubation in a statewide, multicenter Society of Thoracic Surgeons database.

Methods

Records from 39,812 patients undergoing coronary artery bypass grafting or valve operations (2008-2016) and extubated within 24 hours were stratified according to extubation time between 06:00 and 18:00 (day) or between 18:00 and 6:00 (overnight). Outcomes including reintubation, mortality, and composite morbidity-mortality were evaluated using hierarchical regression models adjusted for Society of Thoracic Surgeons predictive risk scores. To further analyze extubation during the night, a subanalysis stratified patients into 3 groups: 06:00 to 18:00, 18:00 to 24:00, and 24:00 to 06:00.

Results

A total of 20,758 patients were extubated overnight (52.1%) and were slightly older (median age 66 vs 65 years, P < .001) with a longer duration of ventilation (4 vs 7 hours, P < .001). Day and overnight extubation were associated with equivalent operative mortality (1.7% vs 1.7%, P = .880), reintubation (3.7% vs 3.4%, P = .141), and composite morbidity-mortality (8.2% vs 8.0%, P = .314). After risk adjustment, overnight extubation was not associated with any difference in reintubation, mortality, or composite morbidity-mortality. On subanalysis, those extubated between 24:00 and 06:00 exhibited increased composite morbidity-mortality (odds ratio, 1.18; P = .001) but no difference in reintubation or mortality.

Conclusions

Extubation overnight was not associated with increased mortality or reintubation. These results suggest that in the appropriate clinical setting, it is safe to routinely extubate cardiac surgery patients overnight.  相似文献   
6.
7.
8.
9.
10.
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   
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