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   1443719篇
  免费   118939篇
  国内免费   6676篇
耳鼻咽喉   17886篇
儿科学   46198篇
妇产科学   38297篇
基础医学   197853篇
口腔科学   38283篇
临床医学   131191篇
内科学   299837篇
皮肤病学   33141篇
神经病学   120742篇
特种医学   58698篇
外国民族医学   275篇
外科学   225014篇
综合类   32964篇
现状与发展   3篇
一般理论   562篇
预防医学   116020篇
眼科学   31104篇
药学   101270篇
  6篇
中国医学   2483篇
肿瘤学   77507篇
  2018年   15731篇
  2017年   12369篇
  2016年   14797篇
  2015年   16610篇
  2014年   23269篇
  2013年   34490篇
  2012年   43447篇
  2011年   46662篇
  2010年   28668篇
  2009年   27898篇
  2008年   43333篇
  2007年   46077篇
  2006年   46782篇
  2005年   45419篇
  2004年   43404篇
  2003年   41897篇
  2002年   39687篇
  2001年   67030篇
  2000年   68607篇
  1999年   57557篇
  1998年   17909篇
  1997年   16059篇
  1996年   16809篇
  1995年   17011篇
  1994年   15741篇
  1993年   14795篇
  1992年   47604篇
  1991年   46191篇
  1990年   44366篇
  1989年   42184篇
  1988年   39121篇
  1987年   38422篇
  1986年   36177篇
  1985年   34999篇
  1984年   26805篇
  1983年   22515篇
  1982年   14431篇
  1981年   12963篇
  1980年   12165篇
  1979年   23839篇
  1978年   17365篇
  1977年   14673篇
  1976年   13423篇
  1975年   13933篇
  1974年   16319篇
  1973年   15607篇
  1972年   14345篇
  1971年   13165篇
  1970年   11997篇
  1969年   11210篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.

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   
5.
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   
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