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   3872篇
  免费   258篇
  国内免费   17篇
耳鼻咽喉   30篇
儿科学   149篇
妇产科学   145篇
基础医学   460篇
口腔科学   63篇
临床医学   468篇
内科学   963篇
皮肤病学   71篇
神经病学   122篇
特种医学   182篇
外科学   210篇
综合类   153篇
现状与发展   1篇
预防医学   444篇
眼科学   53篇
药学   356篇
  1篇
中国医学   103篇
肿瘤学   173篇
  2023年   35篇
  2022年   110篇
  2021年   206篇
  2020年   102篇
  2019年   107篇
  2018年   98篇
  2017年   74篇
  2016年   92篇
  2015年   107篇
  2014年   116篇
  2013年   150篇
  2012年   223篇
  2011年   186篇
  2010年   146篇
  2009年   119篇
  2008年   187篇
  2007年   174篇
  2006年   132篇
  2005年   138篇
  2004年   99篇
  2003年   108篇
  2002年   76篇
  2001年   53篇
  2000年   40篇
  1999年   43篇
  1998年   56篇
  1997年   62篇
  1996年   55篇
  1995年   47篇
  1994年   59篇
  1993年   43篇
  1992年   33篇
  1991年   28篇
  1990年   27篇
  1989年   39篇
  1988年   46篇
  1987年   38篇
  1986年   33篇
  1985年   29篇
  1984年   23篇
  1983年   22篇
  1982年   19篇
  1981年   26篇
  1980年   18篇
  1959年   35篇
  1958年   58篇
  1957年   87篇
  1956年   45篇
  1955年   75篇
  1954年   67篇
排序方式: 共有4147条查询结果,搜索用时 15 毫秒
11.
12.
Anulus fibrosus in bulging intervertebral disks   总被引:1,自引:0,他引:1  
Yu  SW; Haughton  VM; Sether  LA; Wagner  M 《Radiology》1988,169(3):761-763
In this investigation the association of radial tears of the anulus fibrosus and bulging of the intervertebral disk was studied. An index of disk bulging was measured in sagittal anatomic sections in 149 lumbar disks from 31 cadavers. The indexes of disk bulging were correlated with stages of disk development and the presence of an annular tear. The largest disk-bulging indexes were always associated with radial tears of the anulus. Eighty-four percent of the disks with radial tears had disk-bulging indexes greater than 2.5 mm. Most normal adult disks had an index of less than 2.5 mm. The results challenge the concept that the anulus fibrosus is intact in bulging disks, although ruptured in herniated disks.  相似文献   
13.
14.
15.
16.
17.
18.
BACKGROUND: Congenital absence of the inferior rectus muscle is a rare cause of apparent inferior rectus palsy especially in the absence of associated cranial facial anomalies. METHODS: We report three cases of isolated congenital absence of the inferior rectus muscle and its successful surgical management. RESULTS: Failure of the normal embryologic development of the mesodermal complex around the eye can lead to agenesis of the extraocular muscles. In apparent palsies of the inferior rectus muscle and no definite cause, a high index of suspicion and orbital imaging can confirm the diagnosis of congenitally absent inferior rectus preoperatively. Surgical correction may involve inferior transposition of the horizontal rectus muscles. CONCLUSIONS: Although rare, congenital absence of the inferior rectus muscle is a possible cause of apparent inferior rectus muscle palsy particularly in the absence of another identifiable cause. Strabismus surgery in conjunction with intramuscular botulinum toxin injection can offer significant improvement in function and cosmesis of these patients.  相似文献   
19.
Policosanol is a new cholesterol-lowering drug isolated and purified from sugar-cane wax. which prevents the development of lipofundin-induced lesions and foam-cell formation in New Zealand rabbits and Wistar rats. This study was conducted to examine the effects of policosanol on foam-cell formation in carrageenan-induced granulomas in rats. Eighteen Wistar rats were randomly distributed in three experimental groups which received orally for 20 days Tween 20 H2O as vehicle (control group) or policosanol at 2.5 or 25 mg kg?1. At the 11th day. lipofundin was injected intrapcritoneally for 8 days to induce formation of foam cells in the granuloma. At day 13, carrageenan was injected subcutaneously for granuloma induction and seven days later animals were killed. A significant reduction of the foam-cell formation in granulomas of policosanol-treated rats was observed. It is concluded that policosanol prevents the development of foam cells in carrageenan-induced granulomas (extravascular medium) in rats.  相似文献   
20.
Twelve Sardinian patients affected by histologically defined classic Kaposi's sarcoma (KS) were HLA-A, B, C and DR typed. Compared to 220 age and ethnically matched healthy controls, KS patients showed a significant increase in HLA-DR5 (66.6 vs 23.1%, P less than 0.001) and a considerable decrease in HLA-DR3 (8.3 vs 53.6%, P = 0.0055). No definite association was observed for other HLA antigens. These results confirm the existence of an HLA associated genetic control of KS susceptibility and support the hypothesis that HLA-DR5 plays the role of a predisposition marker while HLA-DR3 bears a genetic resistance to the disease.  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