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   1272006篇
  免费   95247篇
  国内免费   1600篇
耳鼻咽喉   16416篇
儿科学   41313篇
妇产科学   35120篇
基础医学   190524篇
口腔科学   34894篇
临床医学   118513篇
内科学   249455篇
皮肤病学   27438篇
神经病学   102639篇
特种医学   46950篇
外国民族医学   265篇
外科学   179896篇
综合类   25822篇
现状与发展   3篇
一般理论   571篇
预防医学   105262篇
眼科学   28149篇
药学   93033篇
  6篇
中国医学   2050篇
肿瘤学   70534篇
  2018年   13809篇
  2017年   10599篇
  2016年   11503篇
  2015年   13298篇
  2014年   18292篇
  2013年   27856篇
  2012年   38073篇
  2011年   40470篇
  2010年   23389篇
  2009年   22535篇
  2008年   38115篇
  2007年   40798篇
  2006年   40363篇
  2005年   39442篇
  2004年   37865篇
  2003年   36230篇
  2002年   35150篇
  2001年   56252篇
  2000年   57271篇
  1999年   48316篇
  1998年   13472篇
  1997年   12291篇
  1996年   12709篇
  1995年   11975篇
  1994年   11161篇
  1993年   10444篇
  1992年   38330篇
  1991年   37802篇
  1990年   36564篇
  1989年   35379篇
  1988年   32769篇
  1987年   32129篇
  1986年   30603篇
  1985年   28843篇
  1984年   21994篇
  1983年   19224篇
  1982年   11385篇
  1981年   10352篇
  1979年   20988篇
  1978年   15425篇
  1977年   12817篇
  1976年   11869篇
  1975年   12835篇
  1974年   15616篇
  1973年   15390篇
  1972年   14532篇
  1971年   13564篇
  1970年   12801篇
  1969年   12079篇
  1968年   11241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