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   1283936篇
  免费   93342篇
  国内免费   2008篇
耳鼻咽喉   18233篇
儿科学   42472篇
妇产科学   37974篇
基础医学   187959篇
口腔科学   35564篇
临床医学   108742篇
内科学   253060篇
皮肤病学   26759篇
神经病学   99905篇
特种医学   50181篇
外国民族医学   366篇
外科学   198760篇
综合类   26566篇
现状与发展   1篇
一般理论   302篇
预防医学   93121篇
眼科学   29204篇
药学   98295篇
  1篇
中国医学   2511篇
肿瘤学   69310篇
  2018年   12052篇
  2016年   10231篇
  2015年   11805篇
  2014年   16278篇
  2013年   24669篇
  2012年   33972篇
  2011年   36415篇
  2010年   21506篇
  2009年   20274篇
  2008年   35371篇
  2007年   38322篇
  2006年   38881篇
  2005年   38129篇
  2004年   36652篇
  2003年   35669篇
  2002年   35146篇
  2001年   58287篇
  2000年   59770篇
  1999年   50874篇
  1998年   14298篇
  1997年   12873篇
  1996年   13134篇
  1995年   12398篇
  1994年   11814篇
  1993年   10900篇
  1992年   41130篇
  1991年   40470篇
  1990年   39999篇
  1989年   38827篇
  1988年   36209篇
  1987年   35452篇
  1986年   33811篇
  1985年   32221篇
  1984年   23970篇
  1983年   20867篇
  1982年   12397篇
  1981年   10952篇
  1979年   22664篇
  1978年   15908篇
  1977年   13749篇
  1976年   12993篇
  1975年   14211篇
  1974年   16696篇
  1973年   16094篇
  1972年   15332篇
  1971年   14241篇
  1970年   13228篇
  1969年   12736篇
  1968年   11981篇
  1967年   10490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