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   1351501篇
  免费   112386篇
  国内免费   6478篇
耳鼻咽喉   16777篇
儿科学   43336篇
妇产科学   36708篇
基础医学   185658篇
口腔科学   36429篇
临床医学   121610篇
内科学   280319篇
皮肤病学   31988篇
神经病学   111572篇
特种医学   56131篇
外国民族医学   274篇
外科学   211857篇
综合类   32604篇
现状与发展   2篇
一般理论   439篇
预防医学   107650篇
眼科学   28195篇
药学   94890篇
  33篇
中国医学   2280篇
肿瘤学   71613篇
  2018年   14263篇
  2017年   11152篇
  2016年   13591篇
  2015年   15169篇
  2014年   20848篇
  2013年   30923篇
  2012年   37170篇
  2011年   39387篇
  2010年   25171篇
  2009年   24571篇
  2008年   36803篇
  2007年   39215篇
  2006年   40244篇
  2005年   38786篇
  2004年   36951篇
  2003年   35903篇
  2002年   33875篇
  2001年   66099篇
  2000年   68030篇
  1999年   56691篇
  1998年   16846篇
  1997年   15131篇
  1996年   16076篇
  1995年   16282篇
  1994年   15142篇
  1993年   14206篇
  1992年   47121篇
  1991年   45774篇
  1990年   44009篇
  1989年   41853篇
  1988年   38806篇
  1987年   38110篇
  1986年   35886篇
  1985年   34647篇
  1984年   26380篇
  1983年   22114篇
  1982年   13869篇
  1981年   12456篇
  1980年   11742篇
  1979年   23548篇
  1978年   17079篇
  1977年   14403篇
  1976年   13192篇
  1975年   13733篇
  1974年   16095篇
  1973年   15398篇
  1972年   14174篇
  1971年   13047篇
  1970年   11886篇
  1969年   11105篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.

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   
3.
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.
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