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   1265916篇
  免费   94812篇
  国内免费   1591篇
耳鼻咽喉   16338篇
儿科学   41028篇
妇产科学   34988篇
基础医学   189680篇
口腔科学   34786篇
临床医学   118032篇
内科学   248126篇
皮肤病学   27303篇
神经病学   102038篇
特种医学   46827篇
外国民族医学   265篇
外科学   178806篇
综合类   25788篇
现状与发展   3篇
一般理论   569篇
预防医学   104839篇
眼科学   28114篇
药学   92687篇
  6篇
中国医学   2023篇
肿瘤学   70073篇
  2018年   13575篇
  2017年   10413篇
  2016年   11345篇
  2015年   13123篇
  2014年   18038篇
  2013年   27530篇
  2012年   37665篇
  2011年   40042篇
  2010年   23112篇
  2009年   22323篇
  2008年   37844篇
  2007年   40446篇
  2006年   40039篇
  2005年   39172篇
  2004年   37631篇
  2003年   36018篇
  2002年   34926篇
  2001年   56090篇
  2000年   57096篇
  1999年   48161篇
  1998年   13427篇
  1997年   12242篇
  1996年   12662篇
  1995年   11938篇
  1994年   11126篇
  1993年   10413篇
  1992年   38237篇
  1991年   37720篇
  1990年   36485篇
  1989年   35305篇
  1988年   32731篇
  1987年   32059篇
  1986年   30565篇
  1985年   28825篇
  1984年   21972篇
  1983年   19226篇
  1982年   11388篇
  1981年   10328篇
  1979年   20972篇
  1978年   15413篇
  1977年   12795篇
  1976年   11859篇
  1975年   12831篇
  1974年   15600篇
  1973年   15381篇
  1972年   14527篇
  1971年   13563篇
  1970年   12795篇
  1969年   12081篇
  1968年   11243篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.

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   
2.
3.
4.
5.
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   
6.
7.
8.
9.
As millions of people turn to social media for health information, better understanding the factors that guide health-related judgments and perceptions in this context is imperative. We report on two Web experiments (n > 400 total) examining the power of society’s widespread weight bias and related stereotypes to influence nutrition judgments in social media spaces. In Experiment 1, meals were judged as lower in nutritional quality when the person who recommended them (the source) was depicted as obese rather than of normal weight, an effect mediated by stereotypic beliefs about the source as a generally unhealthy person. Experiment 2 replicated this effect, which—notably—remained significant when controlling for objective nutritional information (calories and fat content). Results highlight spillover effects of weight bias that extend beyond person perception to color impressions of objects (here, food) that are associated with stigmatized attributes. Implications for everyday nutrition judgments and public health are considered.  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