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   3277974篇
  免费   226367篇
  国内免费   8693篇
耳鼻咽喉   45240篇
儿科学   108170篇
妇产科学   90491篇
基础医学   461738篇
口腔科学   90048篇
临床医学   297771篇
内科学   637152篇
皮肤病学   78722篇
神经病学   265123篇
特种医学   126653篇
外国民族医学   918篇
外科学   488278篇
综合类   65551篇
现状与发展   7篇
一般理论   1179篇
预防医学   246887篇
眼科学   74131篇
药学   245057篇
  13篇
中国医学   7344篇
肿瘤学   182561篇
  2021年   25538篇
  2019年   25986篇
  2018年   36578篇
  2017年   28312篇
  2016年   32870篇
  2015年   37114篇
  2014年   50772篇
  2013年   75521篇
  2012年   100956篇
  2011年   106524篇
  2010年   64029篇
  2009年   61069篇
  2008年   98857篇
  2007年   104994篇
  2006年   106668篇
  2005年   102184篇
  2004年   98081篇
  2003年   94540篇
  2002年   91209篇
  2001年   159500篇
  2000年   163548篇
  1999年   137658篇
  1998年   38955篇
  1997年   34570篇
  1996年   34744篇
  1995年   33564篇
  1994年   30568篇
  1993年   28660篇
  1992年   106420篇
  1991年   102467篇
  1990年   99627篇
  1989年   96388篇
  1988年   88043篇
  1987年   86033篇
  1986年   80933篇
  1985年   77000篇
  1984年   57143篇
  1983年   48155篇
  1982年   28307篇
  1979年   50585篇
  1978年   35294篇
  1977年   30617篇
  1976年   27795篇
  1975年   30133篇
  1974年   35381篇
  1973年   33766篇
  1972年   31872篇
  1971年   29640篇
  1970年   27248篇
  1969年   26236篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.

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   
4.
5.
6.
7.
Direct peroral cholangioscopy (POC) using an ultra‐slim upper endoscope is one modality of POC for intraductal endoscopic evaluation and treatment of the bile duct. Choledochoduodenostomy (CDS) is one modality of biliary bypass surgery that provides a new route to the bile duct. We carried out direct POC using an ultra‐slim upper endoscope without the use of accessories in 10 patients (four sump syndromes, three bile duct strictures and three intrahepatic duct stones) previously undergoing surgical CDS. Direct POC was successful in all patients. The use of an intraductal balloon catheter was required in one patient for advancement of the endoscope into the bile duct. Distal bile ducts with sump syndromes were cleared using baskets and water irrigation under direct POC. Cholangiocarcinoma was diagnosed in one patient with hilar bile duct stricture after cholangioscopic evaluation and a targeting forceps biopsy under direct POC. Intrahepatic duct stones were successfully extracted after intraductal fragmentation under direct POC. Oozing bleeding occurred during intraductal lithotripsy but stopped spontaneously. Direct POC using an ultra‐slim upper endoscope without the assistance of accessories can easily be carried out in patients undergoing CDS.  相似文献   
8.
9.
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   
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