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   2344353篇
  免费   183299篇
  国内免费   7304篇
耳鼻咽喉   30254篇
儿科学   76387篇
妇产科学   64681篇
基础医学   334681篇
口腔科学   65121篇
临床医学   216392篇
内科学   467624篇
皮肤病学   53748篇
神经病学   191499篇
特种医学   91505篇
外国民族医学   522篇
外科学   349342篇
综合类   52728篇
现状与发展   5篇
一般理论   932篇
预防医学   192847篇
眼科学   51610篇
药学   168024篇
  8篇
中国医学   3913篇
肿瘤学   123133篇
  2018年   24093篇
  2016年   21732篇
  2015年   24551篇
  2014年   34199篇
  2013年   51951篇
  2012年   66553篇
  2011年   71387篇
  2010年   43148篇
  2009年   41859篇
  2008年   67241篇
  2007年   71857篇
  2006年   72417篇
  2005年   70437篇
  2004年   67426篇
  2003年   65177篇
  2002年   62651篇
  2001年   106524篇
  2000年   109118篇
  1999年   91804篇
  1998年   27314篇
  1997年   24615篇
  1996年   25625篇
  1995年   25198篇
  1994年   23433篇
  1993年   22030篇
  1992年   75322篇
  1991年   73665篇
  1990年   71263篇
  1989年   68342篇
  1988年   63394篇
  1987年   62371篇
  1986年   58982篇
  1985年   56651篇
  1984年   43134篇
  1983年   37050篇
  1982年   22786篇
  1981年   20607篇
  1980年   19410篇
  1979年   40115篇
  1978年   29316篇
  1977年   24699篇
  1976年   22704篇
  1975年   24187篇
  1974年   28945篇
  1973年   28093篇
  1972年   26188篇
  1971年   24318篇
  1970年   22614篇
  1969年   21277篇
  1968年   19872篇
排序方式: 共有10000条查询结果,搜索用时 0 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.
Metabolism describes the series of chemical reactions that are concerned with the provision of energy to biological systems. They may be divided into reactions involved in energy yield (catabolism: demand exceeds supply), and energy storage (anabolism: supply exceeds demand). Regulation of these pathways is critical for homeostasis, and derangements in metabolism are seen in a wide variety of pathological processes. Understanding metabolism is key to the treatment of many diseases, notably diabetes, as well as underpinning clinical nutritional support.  相似文献   
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