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   1285786篇
  免费   93729篇
  国内免费   2000篇
耳鼻咽喉   18273篇
儿科学   42508篇
妇产科学   38080篇
基础医学   188332篇
口腔科学   35563篇
临床医学   109230篇
内科学   252987篇
皮肤病学   26599篇
神经病学   100187篇
特种医学   50303篇
外国民族医学   366篇
外科学   198926篇
综合类   26662篇
现状与发展   1篇
一般理论   306篇
预防医学   93648篇
眼科学   29199篇
药学   98372篇
  1篇
中国医学   2510篇
肿瘤学   69462篇
  2018年   11972篇
  2015年   11799篇
  2014年   16241篇
  2013年   24697篇
  2012年   34051篇
  2011年   36405篇
  2010年   21430篇
  2009年   20250篇
  2008年   35419篇
  2007年   38350篇
  2006年   38920篇
  2005年   38215篇
  2004年   36792篇
  2003年   35732篇
  2002年   35255篇
  2001年   58359篇
  2000年   59863篇
  1999年   50937篇
  1998年   14322篇
  1997年   12905篇
  1996年   13161篇
  1995年   12415篇
  1994年   11844篇
  1993年   10929篇
  1992年   41172篇
  1991年   40522篇
  1990年   40051篇
  1989年   38884篇
  1988年   36274篇
  1987年   35511篇
  1986年   33875篇
  1985年   32292篇
  1984年   24045篇
  1983年   20925篇
  1982年   12473篇
  1981年   10999篇
  1980年   10282篇
  1979年   22744篇
  1978年   15979篇
  1977年   13810篇
  1976年   13043篇
  1975年   14265篇
  1974年   16765篇
  1973年   16169篇
  1972年   15387篇
  1971年   14292篇
  1970年   13281篇
  1969年   12800篇
  1968年   12032篇
  1967年   10537篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
Turboprop: improved PROPELLER imaging.   总被引:1,自引:0,他引:1  
A variant of periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) MRI, called turboprop, is introduced. This method employs an oscillating readout gradient during each spin echo of the echo train to collect more lines of data per echo train, which reduces the minimum scan time, motion-related artifact, and specific absorption rate (SAR) while increasing sampling efficiency. It can be applied to conventional fast spin-echo (FSE) imaging; however, this article emphasizes its application in diffusion-weighted imaging (DWI). The method is described and compared with conventional PROPELLER imaging, and clinical images collected with this PROPELLER variant are shown.  相似文献   
42.
43.
44.
We report the case of a 38-year-old woman who presented with chronic lower abdominal pain. Her past medical history included a splenectomy due to abdominal trauma. Ultrasound examination revealed four pelvic tumors which, upon laparotomy, were found to be the result of splenosis. Approximately 100 cases of splenosis have been reported but only a minority of them have been published in the gynecological literature. Our case indicates that those involved in pelvic scanning (even of asymptomatic women) and/or treating those complaining of lower abdominal pain or presenting with pelvic tumors should be aware of splenosis as a possible diagnosis.  相似文献   
45.
46.
47.
48.
49.
Neu-Laxova syndrome (NLS) is a rare autosomal recessive syndrome, characterized by severe intrauterine growth retardation (IUGR), microcephaly, abnormal brain development, oedema and ichthyosis. It was first reported in 1971 by Neu et al. (Pediatrics 47: 610-612) and since then no more than 60 cases have been reported. A newborn girl delivered from a 29-year-old healthy mother was admitted to hospital with a thick membrane covering her body and dismorphic appearance. The diagnosis of NLS was made according to characteristic features. The syndrome is known to have a poor prognosis and the baby lived for 9 weeks. This case is one of the longest living cases of NLS and the fourth case reported from Turkey.  相似文献   
50.
The purpose of this study is to determine the role of liver biopsy and outcome of patients undergoing donor evaluation for adult-to-adult right hepatic lobe living donor liver transplantation (LDLT). Records of patients presenting for a comprehensive donor evaluation between 1997 and February 2005 were reviewed. Liver biopsy was performed only in patients with risk factors for abnormal histology. Two hundred and sixty patients underwent a comprehensive donor evaluation and 116 of 260 (45%) were suitable for donation, 14 of 260 (5.4%) did not complete evaluation and 130 of 260 (50%) were rejected. Four patients underwent unsuccessful hepatectomy surgery due to discovery of intraoperative abnormalities. Between 1997 and 2001, the acceptance rate of donor candidates (63%) was higher than 2002-2005 (36%), p < 0.0001. Sixty-six of the 150 eligible patients (44%) fulfilled criteria for liver biopsy and 28 of 66 (42%) had an abnormal finding. Less than half of the patients undergoing donor evaluation were suitable donors and the donor acceptance rate has declined over time. A large proportion of the patients undergoing liver biopsy have abnormal findings. Our evaluation process failed to identify 4 of 103 who had aborted donor surgeries.  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