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   3990066篇
  免费   292155篇
  国内免费   10914篇
耳鼻咽喉   55539篇
儿科学   127212篇
妇产科学   109620篇
基础医学   561882篇
口腔科学   113199篇
临床医学   367391篇
内科学   773998篇
皮肤病学   93948篇
神经病学   325622篇
特种医学   153363篇
外国民族医学   1168篇
外科学   600148篇
综合类   85537篇
现状与发展   12篇
一般理论   1547篇
预防医学   307030篇
眼科学   92866篇
药学   294841篇
  10篇
中国医学   9499篇
肿瘤学   218703篇
  2021年   32968篇
  2019年   32881篇
  2018年   45685篇
  2017年   34931篇
  2016年   40673篇
  2015年   46643篇
  2014年   64019篇
  2013年   94737篇
  2012年   127342篇
  2011年   134365篇
  2010年   80521篇
  2009年   75978篇
  2008年   123678篇
  2007年   130684篇
  2006年   131826篇
  2005年   127080篇
  2004年   121577篇
  2003年   116532篇
  2002年   112522篇
  2001年   187956篇
  2000年   192695篇
  1999年   162567篇
  1998年   47131篇
  1997年   41464篇
  1996年   41323篇
  1995年   39840篇
  1994年   36459篇
  1993年   34114篇
  1992年   126110篇
  1991年   121530篇
  1990年   117990篇
  1989年   113896篇
  1988年   104792篇
  1987年   102688篇
  1986年   96359篇
  1985年   92376篇
  1984年   69082篇
  1983年   58701篇
  1982年   34468篇
  1979年   61854篇
  1978年   43430篇
  1977年   36958篇
  1976年   34084篇
  1975年   36205篇
  1974年   43458篇
  1973年   41479篇
  1972年   39049篇
  1971年   36264篇
  1970年   34029篇
  1969年   32289篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
92.
93.

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   
94.
95.
96.
Metabolism describes the series of chemical reactions that are concerned with the provision of energy to biological systems. They may be divided into reactions involved in energy yield (catabolism: demand exceeds supply), and energy storage (anabolism: supply exceeds demand). Regulation of these pathways is critical for homeostasis, and derangements in metabolism are seen in a wide variety of pathological processes. Understanding metabolism is key to the treatment of many diseases, notably diabetes, as well as underpinning clinical nutritional support.  相似文献   
97.

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   
98.
99.
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