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   3248309篇
  免费   258061篇
  国内免费   6721篇
耳鼻咽喉   46190篇
儿科学   102628篇
妇产科学   89544篇
基础医学   454743篇
口腔科学   92709篇
临床医学   297051篇
内科学   634928篇
皮肤病学   69323篇
神经病学   273443篇
特种医学   127623篇
外国民族医学   1186篇
外科学   487480篇
综合类   78547篇
现状与发展   5篇
一般理论   1373篇
预防医学   263672篇
眼科学   76756篇
药学   237252篇
  5篇
中国医学   6575篇
肿瘤学   172058篇
  2018年   35320篇
  2017年   27025篇
  2016年   29972篇
  2015年   33877篇
  2014年   48726篇
  2013年   73571篇
  2012年   99293篇
  2011年   104821篇
  2010年   61812篇
  2009年   59033篇
  2008年   98123篇
  2007年   104222篇
  2006年   105139篇
  2005年   102262篇
  2004年   97997篇
  2003年   94222篇
  2002年   92142篇
  2001年   150929篇
  2000年   155616篇
  1999年   131070篇
  1998年   38493篇
  1997年   34862篇
  1996年   34550篇
  1995年   33102篇
  1994年   30779篇
  1993年   28839篇
  1992年   103582篇
  1991年   99591篇
  1990年   95912篇
  1989年   92215篇
  1988年   85525篇
  1987年   84117篇
  1986年   79300篇
  1985年   75777篇
  1984年   57851篇
  1983年   49293篇
  1982年   30221篇
  1981年   26887篇
  1979年   53521篇
  1978年   37789篇
  1977年   31680篇
  1976年   29782篇
  1975年   31026篇
  1974年   38149篇
  1973年   36453篇
  1972年   34206篇
  1971年   31451篇
  1970年   29755篇
  1969年   27679篇
  1968年   25626篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
72.
73.
74.
75.
76.
77.
This study used the National Survey of Ambulatory Surgery (NSAS) database to measure the incidence of and risk factors for symptoms in the ambulatory surgery center and problems within 24 h after isolated carpal tunnel release (CTR). The NSAS contained records on 400,000 adult patients with carpal tunnel syndrome who were treated with CTR in 2006, based on ICD-9 codes. The type of anesthesia used and factors associated with symptoms and problems were sought in bivariate and multivariable statistical analyses. The mean duration of the procedure was 16 ± 8.8 min. Only 5 % were performed under local anesthesia without sedation, 45 % with IV sedation, 28 % regional anesthesia, and 19 % general anesthesia. Symptoms in the ambulatory surgery center or a problem within 24 h after discharge were recorded in 10 % of patients, all of them minor and transient, including difficulties with pain and its treatment. The strongest risk factors were male sex, age of 45 years and older, and participation of an anesthesiologist. Local anesthesia and regional anesthesia were associated with more perioperative symptoms and postoperative problems. Most CTR are performed with some sedation in the United States. CTR is a safe procedure: one in 10 patients will experience a minor issue in the perioperative or immediate postoperative period.  相似文献   
78.
79.
80.
Delayed contrast enhancement after injection of a gadolinium-chelate (Gd-chelate) is a reference imaging method to detect myocardial tissue changes. Its localization within the thickness of the myocardial wall allows differentiating various pathological processes such as myocardial infarction (MI), inflammatory myocarditis, and cardiomyopathies. The aim of the study was first to characterize benign myocarditis using quantitative delayed-enhancement imaging and then to investigate whether the measure of the extracellular volume fraction (ECV) can be used to discriminate between MI and myocarditis.In 6 patients with acute benign myocarditis (32.2 ± 13.8 year-old, subepicardial late gadolinium enhancement [LGE]) and 18 patients with MI (52.3 ± 10.9 year-old, subendocardial/transmural LGE), myocardial T1 was determined using the Modified Look-Locker Imaging (MOLLI) sequence at 3 Tesla before and after Gd-chelate injection. T1 values were compared in LGE and normal regions of the myocardium. The myocardial T1 values were normalized to the T1 of blood, and the ECV was calculated from T1 values of myocardium and blood pre- and post-Gd injection.In both myocarditis and MI, the T1 was lower in LGE regions than in normal regions of the left ventricle. T1 of LGE areas was significantly higher in myocarditis than in MI (446.8 ± 45.8 vs 360.5 ± 66.9 ms, P = 0.003) and ECV was lower in myocarditis than in MI (34.5 ± 3.3 vs 53.8 ± 13.0 %, P = 0.004).Both inflammatory process and chronic fibrosis induce LGE (subepicardial in myocarditis and subendocardial in MI). The present study demonstrates that the determination of T1 and ECV is able to differentiate the 2 histological patterns.Further investigation will indicate whether the severity of ECV changes might help refine the predictive risk of LGE in myocarditis.  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