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   4020966篇
  免费   291829篇
  国内免费   9061篇
耳鼻咽喉   55937篇
儿科学   131989篇
妇产科学   110783篇
基础医学   574777篇
口腔科学   112171篇
临床医学   371020篇
内科学   776310篇
皮肤病学   93034篇
神经病学   326668篇
特种医学   152303篇
外国民族医学   1143篇
外科学   601658篇
综合类   83866篇
现状与发展   15篇
一般理论   1609篇
预防医学   315451篇
眼科学   93863篇
药学   296859篇
  15篇
中国医学   7864篇
肿瘤学   214521篇
  2019年   32430篇
  2018年   44810篇
  2017年   33947篇
  2016年   39057篇
  2015年   43990篇
  2014年   61478篇
  2013年   93106篇
  2012年   125467篇
  2011年   133243篇
  2010年   80085篇
  2009年   76199篇
  2008年   124671篇
  2007年   132578篇
  2006年   134477篇
  2005年   129775篇
  2004年   124923篇
  2003年   120354篇
  2002年   116364篇
  2001年   183280篇
  2000年   188130篇
  1999年   159094篇
  1998年   47354篇
  1997年   41584篇
  1996年   41740篇
  1995年   40116篇
  1994年   36836篇
  1993年   34642篇
  1992年   124733篇
  1991年   120928篇
  1990年   117629篇
  1989年   114004篇
  1988年   104919篇
  1987年   102818篇
  1986年   96821篇
  1985年   92787篇
  1984年   69391篇
  1983年   59077篇
  1982年   35269篇
  1981年   31749篇
  1979年   62983篇
  1978年   44805篇
  1977年   37828篇
  1976年   35602篇
  1975年   38027篇
  1974年   45340篇
  1973年   43210篇
  1972年   40666篇
  1971年   38186篇
  1970年   35163篇
  1969年   33836篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
92.

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   
93.
94.
95.
96.

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   
97.
98.
99.
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   
100.
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