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   2582577篇
  免费   189345篇
  国内免费   7559篇
耳鼻咽喉   34272篇
儿科学   85179篇
妇产科学   71569篇
基础医学   363619篇
口腔科学   69670篇
临床医学   234322篇
内科学   515095篇
皮肤病学   62449篇
神经病学   213413篇
特种医学   99903篇
外国民族医学   736篇
外科学   386754篇
综合类   50385篇
现状与发展   5篇
一般理论   968篇
预防医学   195910篇
眼科学   56660篇
药学   187962篇
  8篇
中国医学   5331篇
肿瘤学   145271篇
  2021年   19998篇
  2019年   20643篇
  2018年   29308篇
  2017年   22624篇
  2016年   26255篇
  2015年   29536篇
  2014年   40483篇
  2013年   60467篇
  2012年   80287篇
  2011年   84557篇
  2010年   51041篇
  2009年   49191篇
  2008年   79095篇
  2007年   83902篇
  2006年   85629篇
  2005年   81803篇
  2004年   78783篇
  2003年   76101篇
  2002年   73407篇
  2001年   128440篇
  2000年   131357篇
  1999年   110531篇
  1998年   31275篇
  1997年   27941篇
  1996年   28242篇
  1995年   27395篇
  1994年   25083篇
  1993年   23427篇
  1992年   85179篇
  1991年   81589篇
  1990年   78815篇
  1989年   76079篇
  1988年   69494篇
  1987年   68023篇
  1986年   63576篇
  1985年   60533篇
  1984年   44952篇
  1983年   37957篇
  1982年   22460篇
  1981年   19987篇
  1979年   38968篇
  1978年   27441篇
  1977年   23258篇
  1976年   21498篇
  1975年   22814篇
  1974年   26787篇
  1973年   25370篇
  1972年   23749篇
  1971年   21955篇
  1970年   20185篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
61.
62.

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   
63.
64.
65.

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   
66.
67.
68.
69.
Henna, derived from a combination of natural leaves and coloring additives, is a common decorative dye traditionally used in many Islamic religious celebrations. Para‐phenylenediamine (PPD), a major component of black henna tattoo, is a strong sensitizer and common allergen. We report a case of severe connubial allergic contact dermatitis after black henna heterotransfer in a girl.  相似文献   
70.
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