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   538375篇
  免费   41121篇
  国内免费   14719篇
耳鼻咽喉   5245篇
儿科学   12543篇
妇产科学   8345篇
基础医学   52459篇
口腔科学   11331篇
临床医学   57993篇
内科学   64374篇
皮肤病学   6475篇
神经病学   27173篇
特种医学   12179篇
外国民族医学   58篇
外科学   50821篇
综合类   88716篇
现状与发展   35篇
一般理论   74篇
预防医学   47926篇
眼科学   9467篇
药学   52033篇
  581篇
中国医学   57834篇
肿瘤学   28553篇
  2023年   8096篇
  2022年   13092篇
  2021年   20966篇
  2020年   19559篇
  2019年   24280篇
  2018年   21759篇
  2017年   19580篇
  2016年   17414篇
  2015年   16661篇
  2014年   32475篇
  2013年   34096篇
  2012年   29949篇
  2011年   32715篇
  2010年   26935篇
  2009年   24715篇
  2008年   23715篇
  2007年   25461篇
  2006年   22418篇
  2005年   20383篇
  2004年   17069篇
  2003年   14959篇
  2002年   11467篇
  2001年   10722篇
  2000年   8831篇
  1999年   7775篇
  1998年   5991篇
  1997年   5559篇
  1996年   5142篇
  1995年   4861篇
  1994年   4477篇
  1993年   3721篇
  1992年   3523篇
  1991年   3080篇
  1990年   2664篇
  1989年   2399篇
  1988年   2276篇
  1987年   1870篇
  1986年   1615篇
  1985年   4344篇
  1984年   5307篇
  1983年   3632篇
  1982年   4219篇
  1981年   3898篇
  1980年   3453篇
  1979年   3154篇
  1978年   2730篇
  1977年   2084篇
  1976年   2343篇
  1975年   1758篇
  1974年   1533篇
排序方式: 共有10000条查询结果,搜索用时 156 毫秒
101.

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   
102.
Erosive pustular dermatosis of the scalp (EPDS) is an uncommon chronic inflammatory response to scalp trauma that usually resolves with cicatricial alopecia. It most commonly affects elderly patients with a history of actinic damage. Herein, we describe a 16‐year‐old girl with acrofacial dysostosis type 1 presenting after surgery with crusting purulent scalp lesions, whose clinical presentation and histopathologic findings were consistent with EPDS. A review of the literature on EPDS in children is also detailed.  相似文献   
103.
目的探讨接受选择性淋巴结照射(ENI)的食管鳞癌患者预后和失败模式。方法回顾性分析2005年1月至2012年12月河北医科大学第四医院收治的179例符合入组条件的食管鳞癌患者,分析肿瘤局部相关因素预测患者预后的价值,分析影响患者近期疗效、预后的影响因素,并对影响患者总生存率(OS)、无进展生存率(PFS)和复发的指标分别进行单因素和多因素分析。结果全组患者1、3、5年OS和PFS分别为77.1%、40.1%、26.0%和62.6%、30.6%、20.3%。多因素分析结果显示声音嘶哑、cN分期、cTNM分期、GTV-横径(GTV-D)和GTV-体积/长度(GTV-V/L)为影响患者OS的独立性影响因素(P<0.05);声音嘶哑、cTNM分期和近期疗效为影响患者PFS的独立性影响因素(P<0.05)。全组有75例(41.9%)患者出现复发,61例(34.1%)远处转移,其中19例(10.6%)为合并复发和远处转移。75例复发患者中64例(85.3%)患者为单纯食管复发,4例(5.3%)为单纯淋巴结复发,另7例(9.3%)患者为食管合并淋巴结复发。治疗后达完全缓解(CR)的63例患者中有18例患者出现复发,其中仅有2例患者出现淋巴结复发;logistic多因素分析结果显示患者周边组织/器官受侵、GTV-D和近期疗效为影响患者复发的独立性影响因素(P<0.05)。结论食管鳞癌患者接受ENI确实可行,其失败主要模式仍为食管复发;治疗前声音嘶哑、GTV-D和GTV-V/L较大、临床分期较晚和近期疗效不佳为患者预后较差的指标;肿瘤周边组织受侵、GTV-D和近期疗效是影响患者失败的独立性因素。  相似文献   
104.
105.
106.
107.
108.
109.
Dosage form is a mean used for the delivery of drug to a living body. In order to get the desired effect the drug should be delivered to its site of action at such rate and concentration to achieve the maximum therapeutic effect and minimum adverse effect. Since oral route is still widely accepted route but having a common drawback of difficulty in swallowing of tablets and capsules. Therefore a lot of research has been done on novel drug delivery systems. This review is about oral dispersible tablets a novel approach in drug delivery systems that are now a day''s more focused in formulation world, and laid a new path that, helped the patients to build their compliance level with the therapy, also reduced the cost and ease the administration especially in case of pediatrics and geriatrics. Quick absorption, rapid onset of action and reduction in drug loss properties are the basic advantages of this dosage form.  相似文献   
110.
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