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   3877953篇
  免费   321076篇
  国内免费   20366篇
耳鼻咽喉   51796篇
儿科学   121400篇
妇产科学   98843篇
基础医学   602710篇
口腔科学   104442篇
临床医学   353664篇
内科学   687849篇
皮肤病学   100222篇
神经病学   322639篇
特种医学   151455篇
外国民族医学   294篇
外科学   591916篇
综合类   134318篇
现状与发展   46篇
一般理论   2382篇
预防医学   318729篇
眼科学   91519篇
药学   272922篇
  104篇
中国医学   17481篇
肿瘤学   194664篇
  2021年   58957篇
  2020年   38030篇
  2019年   60699篇
  2018年   75127篇
  2017年   57794篇
  2016年   63699篇
  2015年   78824篇
  2014年   114373篇
  2013年   180431篇
  2012年   114850篇
  2011年   117237篇
  2010年   128308篇
  2009年   130181篇
  2008年   101946篇
  2007年   106370篇
  2006年   115268篇
  2005年   109327篇
  2004年   109389篇
  2003年   99443篇
  2002年   87862篇
  2001年   138559篇
  2000年   131614篇
  1999年   123328篇
  1998年   69354篇
  1997年   66019篇
  1996年   63542篇
  1995年   59014篇
  1994年   52939篇
  1993年   49200篇
  1992年   85411篇
  1991年   81263篇
  1990年   76951篇
  1989年   75366篇
  1988年   69255篇
  1987年   67424篇
  1986年   63731篇
  1985年   62932篇
  1984年   54997篇
  1983年   49691篇
  1982年   43693篇
  1981年   41044篇
  1980年   38517篇
  1979年   44933篇
  1978年   38304篇
  1977年   34972篇
  1976年   32011篇
  1975年   30834篇
  1974年   32551篇
  1973年   31247篇
  1972年   29075篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
132.
133.
134.
135.
136.
Moderate sedatives have been increasingly used to improve patient comfort during flexible bronchoscopy (FB). However, routine use of moderate sedation during FB is controversial because its efficacy and safety are not well established.This study aims to evaluate the efficacy and safety of moderate sedation during FB.A search was made of Medline, EMBASE, and the Cochrane Library to May 2014.Randomized controlled trials (RCTs) and quasi-RCTs were included.The main analysis was designed to examine the efficacy of moderate sedation during FB in sedation than no-sedation.The willingness to repeat FB was significantly more in sedation than no-sedation (odds ratio [OR] 2.30; 95% confidence interval [CI] 1.11–4.73; P = 0.02; I2 = 22.5). The duration of FB was shorter in sedation group than no-sedation group (standardized mean difference [SMD] −0.21; 95% CI −0.38 to −0.03; P = 0.02; I2 = 78.3%). Event of hypoxia was not significantly different between sedation and no-sedation groups (OR 0.86; 95% CI 0.42–1.73; P = 0.67; I2 = 0%). The SpO2 during procedure was not different between sedation and no-sedation groups (SMD −0.14; 95% CI −0.37 to 0.08; P = 0.21; I2 = 49.9%). However, in subgroup analysis without supplemental oxygen, the SpO2 was significantly lower in sedation than no-sedation group (SMD −0.45; 95% CI −0.78 to −0.11; P = 0.01; I2 = 0.0%).According to this meta-analysis, moderate sedation in FB would be useful in patients who will require repeated bronchoscopies as well as safe in respiratory depression. To our knowledge, although the various sedative drugs are already used in the real field, this analysis was the first attempt to quantify objective results. We anticipate more definite and studies designed to elucidate standardized outcomes for moderate sedation in FB.  相似文献   
137.
138.
139.
Coronary embolism (CE) is an uncommon and unique cause of acute myocardial infarction. In this report, we review 216 cases of CE including 2 new cases from our institution. The mean patient age was 52.5 years and 62% of the patients were males. Chest pain was the most common presenting symptom followed by dyspnea, and the most commonly affected vessel was the left anterior descending artery. Leading etiologies of the embolus were atrial fibrillation, septic emboli, and iatrogenic causes. Treatment approaches varied with thrombus aspiration being used in 30% of cases. In-hospital mortality rate was 36% and 13% of the cases were complicated by cerebrovascular accident. CE is a unique pathology that leads to acute myocardial infarction. It portends a high mortality rate and requires a high level of suspicion as symptoms may be misleading. Further research is needed in order to improve recognition and management and to lower associated mortality.  相似文献   
140.
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   
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