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   1342970篇
  免费   112532篇
  国内免费   6378篇
耳鼻咽喉   16761篇
儿科学   43176篇
妇产科学   36755篇
基础医学   184261篇
口腔科学   36418篇
临床医学   121113篇
内科学   279292篇
皮肤病学   31956篇
神经病学   110826篇
特种医学   55728篇
外国民族医学   275篇
外科学   210872篇
综合类   31589篇
现状与发展   2篇
一般理论   422篇
预防医学   106934篇
眼科学   28167篇
药学   94018篇
  5篇
中国医学   2228篇
肿瘤学   71082篇
  2018年   13462篇
  2017年   10693篇
  2016年   12869篇
  2015年   14384篇
  2014年   20066篇
  2013年   29886篇
  2012年   36481篇
  2011年   39094篇
  2010年   24510篇
  2009年   24019篇
  2008年   36534篇
  2007年   38947篇
  2006年   40087篇
  2005年   38677篇
  2004年   36877篇
  2003年   35986篇
  2002年   33999篇
  2001年   66179篇
  2000年   68030篇
  1999年   56717篇
  1998年   16780篇
  1997年   15056篇
  1996年   16061篇
  1995年   16278篇
  1994年   15135篇
  1993年   14185篇
  1992年   47166篇
  1991年   45796篇
  1990年   44034篇
  1989年   41883篇
  1988年   38824篇
  1987年   38133篇
  1986年   35918篇
  1985年   34711篇
  1984年   26409篇
  1983年   22156篇
  1982年   13863篇
  1981年   12475篇
  1980年   11742篇
  1979年   23596篇
  1978年   17110篇
  1977年   14416篇
  1976年   13212篇
  1975年   13745篇
  1974年   16143篇
  1973年   15435篇
  1972年   14209篇
  1971年   13060篇
  1970年   11901篇
  1969年   11117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