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   2435174篇
  免费   184988篇
  国内免费   3739篇
耳鼻咽喉   33983篇
儿科学   79461篇
妇产科学   68498篇
基础医学   345820篇
口腔科学   71591篇
临床医学   216120篇
内科学   468202篇
皮肤病学   53274篇
神经病学   192485篇
特种医学   97564篇
外国民族医学   665篇
外科学   370516篇
综合类   56675篇
现状与发展   4篇
一般理论   772篇
预防医学   182519篇
眼科学   56295篇
药学   188186篇
  10篇
中国医学   5178篇
肿瘤学   136083篇
  2018年   23556篇
  2016年   20819篇
  2015年   23736篇
  2014年   32640篇
  2013年   49058篇
  2012年   66608篇
  2011年   70285篇
  2010年   41565篇
  2009年   39419篇
  2008年   66723篇
  2007年   70516篇
  2006年   71854篇
  2005年   69213篇
  2004年   67653篇
  2003年   64784篇
  2002年   63158篇
  2001年   119735篇
  2000年   123525篇
  1999年   104063篇
  1998年   27605篇
  1997年   24711篇
  1996年   24598篇
  1995年   23711篇
  1994年   22001篇
  1993年   20771篇
  1992年   83184篇
  1991年   80505篇
  1990年   79057篇
  1989年   76406篇
  1988年   70405篇
  1987年   69192篇
  1986年   65649篇
  1985年   62950篇
  1984年   46482篇
  1983年   39847篇
  1982年   22871篇
  1981年   20232篇
  1980年   19054篇
  1979年   43559篇
  1978年   29937篇
  1977年   25797篇
  1976年   23632篇
  1975年   25591篇
  1974年   30783篇
  1973年   29674篇
  1972年   27697篇
  1971年   26095篇
  1970年   23936篇
  1969年   22708篇
  1968年   20609篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
32.
33.
Academic output is just one aspect of a successful career as a plastic surgeon. However, for those with a strong interest in academia, the academic output of a department will likely be a key factor when deciding how to rank jobs. The aim of this study was to quantify and rank the academic output of plastic surgery units across the UK and Ireland. The Institute for Scientific Information (ISI) Web of Science Bibliometric analysis tool was used to collate cumulative (1950–2016), 10 year (2006–2016) and 3 years (2013–2015) research output data for plastic surgery units in the UK and Ireland. Sixty-six plastic surgery units were identified. Departments were ranked for each time period according to the number of papers produced, number of citations (Nc) and h-index (a measure of the impact of scientific output). The top 3 departments for number of papers in the last 10 years were The Royal Free Hospital, London (226) Broomfield Hospital, Chelmsford (218), and Morriston Hospital and Swansea (188). The top 3 for h-number were The Royal Free Hospital (21) Wythenshawe Hospital, Manchester (18) and Morriston Hospital (17). Academic output varies across plastic surgery units in the UK and Ireland. A number of departments have consistently maintained high academic outputs across the years and will be of interest to surgeons hoping to pursue a career in academia.  相似文献   
34.
35.
36.
37.
To determine percent of patients without malignancy and ≤ 40 years of age with high cumulative radiation doses through recurrent CT exams and assess imaging appropriateness. From the cohort of patients who received cumulative effective dose (CED) of ≥ 100 mSv over a 5-year period, a sub-set was identified with non-malignant disease. The top 50 clinical indications leading to multiple CTs were determined. Clinical decision support (CDS) system scores were analyzed using a widely adopted standard of 1–3 (red) as “not usually appropriate,” 4–6 (yellow) “may or may not be appropriate,” and 7–9 (green) “usually appropriate.” Clinicians reviewed patient records to assess compliance with appropriate use criteria (AUC). 9.6% of patients in our series were with non-malignant conditions and 1.4% with age ≤ 40 years. CDS scores (rounded) were 2% red, 38% yellow, 27% green, and 33% unscored CTs. Clinical society guidelines for CT exams, wherever available, were followed in 87.5 to 100% of cases. AUCs were not available for several clinical indications as also referral guidelines for serial CT imaging. More than half of CT exams were unrelated to follow-up of a primary chronic disease. We are faced with a situation wherein patients in age ≤ 40 years require or are thought to require many CT exams over the course of a few years but the radiation risk creates concern. There is a fair number of conditions for which AUC are not available. Suggested solutions include development of CT scanners with lesser radiation dose and further development of appropriateness criteria.  相似文献   
38.
39.

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   
40.
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   
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