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   3211901篇
  免费   238320篇
  国内免费   7108篇
耳鼻咽喉   43937篇
儿科学   104694篇
妇产科学   87236篇
基础医学   471056篇
口腔科学   89711篇
临床医学   300231篇
内科学   614806篇
皮肤病学   68753篇
神经病学   258982篇
特种医学   118795篇
外国民族医学   810篇
外科学   471376篇
综合类   69894篇
现状与发展   13篇
一般理论   1242篇
预防医学   262525篇
眼科学   74307篇
药学   238930篇
  16篇
中国医学   6832篇
肿瘤学   173183篇
  2021年   25910篇
  2019年   26821篇
  2018年   37182篇
  2017年   28061篇
  2016年   31036篇
  2015年   35210篇
  2014年   49319篇
  2013年   75254篇
  2012年   103209篇
  2011年   109968篇
  2010年   65055篇
  2009年   60775篇
  2008年   102348篇
  2007年   108804篇
  2006年   109642篇
  2005年   106165篇
  2004年   101362篇
  2003年   97268篇
  2002年   94041篇
  2001年   142679篇
  2000年   146627篇
  1999年   123464篇
  1998年   36668篇
  1997年   32266篇
  1996年   32254篇
  1995年   30507篇
  1994年   28327篇
  1993年   26649篇
  1992年   96921篇
  1991年   95132篇
  1990年   92557篇
  1989年   88726篇
  1988年   81895篇
  1987年   80298篇
  1986年   75829篇
  1985年   72700篇
  1984年   54361篇
  1983年   46450篇
  1982年   27816篇
  1979年   50106篇
  1978年   35809篇
  1977年   29643篇
  1976年   28655篇
  1975年   30329篇
  1974年   36619篇
  1973年   35301篇
  1972年   32937篇
  1971年   31051篇
  1970年   28782篇
  1969年   27005篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.

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   
83.
84.
85.
86.
87.

Introduction

Several studies demonstrated that simulator-acquired skill transfer to the operating room is incomplete. Our objective was to identify trainee characteristics that predict the transfer of simulator-acquired skill to the operating room.

Methods

Trainees completed baseline assessments including intracorporeal suturing (IS) performance, attentional selectivity, self-reported use of mental skills, and self-reported prior clinical and simulated laparoscopic experience and confidence. Residents then followed proficiency-based laparoscopic skills training, and their skill transfer was assessed on a live-anesthetized porcine model. Predictive characteristics for transfer test performance were assessed using multiple linear regression.

Results

Thirty-eight residents completed the study. Automaticity, attentional selectivity, resident perceived ability with laparoscopy and simulators, and post-training IS performance were predictive of IS performance during the transfer test.

Conclusions

Promoting automaticity, self-efficacy, and attention selectivity may help improve the transfer of simulator-acquired skill. Mental skills training and training to automaticity may therefore be valuable interventions to achieve this goal.  相似文献   
88.
89.
90.
While previous randomised controlled trials and meta-analyses offer only limited evidence for the effectiveness of cognitive rehabilitation, qualitative studies examining patient perspectives report more positive outcomes. This meta-synthesis of qualitative studies examined patient perspectives of cognitive rehabilitation for memory, attention, and executive function problems in people with multiple sclerosis. Using set eligibility criteria, we screened electronic databases, reference lists, and academic networks for relevant papers. Seven papers (195 participants) were selected. Two independent researchers conducted quality appraisals of papers. Data analysis, guided by the thematic synthesis approach, yielded six main themes. These suggested that patients benefitted from the group environment in rehabilitation. Cognitive rehabilitation facilitated the participants’ reflection and awareness of their cognitive deficits, and was associated with increased knowledge and understanding of their illness. Increased strategy use was reported and associated with improvements in cognitive functioning and greater confidence and perseverance. Participants reported emotional and social improvements, and felt more optimistic. Overall, these changes had a positive impact on participants’ quality of life. This synthesis of qualitative studies indicates that people with multiple sclerosis who experience cognitive deficits benefit from cognitive rehabilitation programmes. This finding must, however, be viewed in light of the limitations of this meta-synthesis. The meta-synthesis was registered in the PROSPERO database under CRD42017040148.  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