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   1845124篇
  免费   132896篇
  国内免费   4282篇
耳鼻咽喉   23930篇
儿科学   59754篇
妇产科学   49007篇
基础医学   260924篇
口腔科学   51817篇
临床医学   166342篇
内科学   364602篇
皮肤病学   40966篇
神经病学   146377篇
特种医学   69090篇
外国民族医学   252篇
外科学   278720篇
综合类   40941篇
现状与发展   7篇
一般理论   714篇
预防医学   135672篇
眼科学   44340篇
药学   133467篇
  7篇
中国医学   4647篇
肿瘤学   110726篇
  2021年   15132篇
  2019年   15825篇
  2018年   22720篇
  2017年   17200篇
  2016年   18952篇
  2015年   21788篇
  2014年   30383篇
  2013年   44610篇
  2012年   62030篇
  2011年   65418篇
  2010年   38413篇
  2009年   35915篇
  2008年   61022篇
  2007年   64997篇
  2006年   65113篇
  2005年   62645篇
  2004年   60436篇
  2003年   57354篇
  2002年   55251篇
  2001年   93113篇
  2000年   94571篇
  1999年   78315篇
  1998年   21696篇
  1997年   18988篇
  1996年   18816篇
  1995年   18076篇
  1994年   16506篇
  1993年   15221篇
  1992年   58285篇
  1991年   56097篇
  1990年   53693篇
  1989年   51449篇
  1988年   46874篇
  1987年   45561篇
  1986年   42978篇
  1985年   40798篇
  1984年   30417篇
  1983年   25900篇
  1982年   15299篇
  1981年   13693篇
  1979年   26214篇
  1978年   18351篇
  1977年   15609篇
  1976年   14491篇
  1975年   15059篇
  1974年   18153篇
  1973年   17360篇
  1972年   16009篇
  1971年   14678篇
  1970年   13639篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
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   
5.
6.
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   
7.
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   
8.
9.

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   
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