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   1341206篇
  免费   112308篇
  国内免费   6375篇
耳鼻咽喉   16729篇
儿科学   43105篇
妇产科学   36595篇
基础医学   183977篇
口腔科学   36297篇
临床医学   120892篇
内科学   279110篇
皮肤病学   31917篇
神经病学   110650篇
特种医学   55627篇
外国民族医学   276篇
外科学   210683篇
综合类   31534篇
现状与发展   2篇
一般理论   414篇
预防医学   106810篇
眼科学   28176篇
药学   93847篇
  5篇
中国医学   2227篇
肿瘤学   71016篇
  2018年   13428篇
  2017年   10653篇
  2016年   12827篇
  2015年   14341篇
  2014年   20004篇
  2013年   29812篇
  2012年   36350篇
  2011年   39033篇
  2010年   24437篇
  2009年   23961篇
  2008年   36475篇
  2007年   38870篇
  2006年   40015篇
  2005年   38593篇
  2004年   36817篇
  2003年   35912篇
  2002年   33933篇
  2001年   66134篇
  2000年   68000篇
  1999年   56664篇
  1998年   16750篇
  1997年   15048篇
  1996年   16036篇
  1995年   16258篇
  1994年   15112篇
  1993年   14176篇
  1992年   47163篇
  1991年   45804篇
  1990年   44014篇
  1989年   41869篇
  1988年   38790篇
  1987年   38111篇
  1986年   35888篇
  1985年   34661篇
  1984年   26378篇
  1983年   22127篇
  1982年   13858篇
  1981年   12462篇
  1980年   11729篇
  1979年   23566篇
  1978年   17090篇
  1977年   14402篇
  1976年   13192篇
  1975年   13733篇
  1974年   16109篇
  1973年   15417篇
  1972年   14187篇
  1971年   13049篇
  1970年   11890篇
  1969年   11116篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.

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   
4.
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   
5.
6.
7.
8.
9.
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   
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