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   2069352篇
  免费   135351篇
  国内免费   5318篇
耳鼻咽喉   29017篇
儿科学   64872篇
妇产科学   53955篇
基础医学   303281篇
口腔科学   58095篇
临床医学   183697篇
内科学   397874篇
皮肤病学   47975篇
神经病学   156272篇
特种医学   76720篇
外国民族医学   448篇
外科学   306019篇
综合类   42167篇
现状与发展   4篇
一般理论   515篇
预防医学   147469篇
眼科学   48891篇
药学   161813篇
  11篇
中国医学   6849篇
肿瘤学   124077篇
  2021年   17046篇
  2019年   17577篇
  2018年   27163篇
  2017年   20310篇
  2016年   22062篇
  2015年   24695篇
  2014年   32298篇
  2013年   47943篇
  2012年   68198篇
  2011年   71022篇
  2010年   40413篇
  2009年   36791篇
  2008年   64508篇
  2007年   69480篇
  2006年   68991篇
  2005年   65571篇
  2004年   62697篇
  2003年   59518篇
  2002年   57321篇
  2001年   105144篇
  2000年   107642篇
  1999年   89747篇
  1998年   22776篇
  1997年   19582篇
  1996年   19285篇
  1995年   18197篇
  1994年   16471篇
  1993年   15448篇
  1992年   66456篇
  1991年   64297篇
  1990年   62724篇
  1989年   60796篇
  1988年   55357篇
  1987年   53710篇
  1986年   50795篇
  1985年   47489篇
  1984年   34489篇
  1983年   29109篇
  1982年   16062篇
  1979年   30987篇
  1978年   21096篇
  1977年   18504篇
  1976年   16402篇
  1975年   18734篇
  1974年   21848篇
  1973年   21109篇
  1972年   20049篇
  1971年   18967篇
  1970年   17711篇
  1969年   16897篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
We report two British cases of liver abscess, due to Klebsiella pneumoniae and associated with synchronous infection elsewhere, which required liver resection for definitive treatment. They illustrate the geographic spread of aggressive K pneumoniae liver infection and demonstrate the importance of early aggressive treatment.  相似文献   
2.
3.
In the current immunosuppressive therapy era, vessel thrombosis is the most common cause of early graft loss after renal transplantation. The prevalence of IgA anti–β2-glycoprotein I antibodies (IgA-aB2GPI-ab) in patients on dialysis is elevated (>30%), and these antibodies correlate with mortality and cardiovascular morbidity. To evaluate the effect of IgA-aB2GPI-ab in patients with transplants, we followed all patients transplanted from 2000 to 2002 in the Hospital 12 de Octubre prospectively for 10 years. Presence of IgA-aB2GPI-ab in pretransplant serum was examined retrospectively. Of 269 patients, 89 patients were positive for IgA-aB2GPI-ab (33%; group 1), and the remaining patients were negative (67%; group 2). Graft loss at 6 months post-transplant was significantly higher in group 1 (10 of 89 versus 3 of 180 patients in group 2; P=0.002). The most frequent cause of graft loss was thrombosis of the vessels, which was observed only in group 1 (8 of 10 versus 0 of 3 patients in group 2; P=0.04). Multivariate analysis showed that the presence of IgA-aB2GPI-ab was an independent risk factor for early graft loss (P=0.04) and delayed graft function (P=0.04). There were no significant differences regarding patient survival between the two groups. Graft survival was similar in both groups after 6 months. In conclusion, patients with pretransplant IgA-aB2GPI-ab have a high risk of early graft loss caused by thrombosis and a high risk of delayed graft function. Therefore, pretransplant IgA-aB2GPI-ab may have a detrimental effect on early clinical outcomes after renal transplantation.  相似文献   
4.
Haemophilia is a common cause of genetically inherited bleeding disorders. Pseudotumours occur in 1–2 % of persons with severe forms of haemophilia. These are a result of repeated haemorrhage into soft tissues, subperiosteum or a site of bone fracture with inadequate resorption of the extravasated blood. There are a number of therapeutic alternatives for this dangerous condition: surgical removal, percutaneous management, irradiation, embolization etc. In this case report, we describe the natural history, clinical course and successful surgical management of a patient with haemophilia who presented with a massive pseudotumour. We also briefly review the relevant literature on the various therapeutic modalities that have been implemented in the management of this rare complication. Though surgeons may be averse to operate on haemophiliacs, primary surgical management as done in our case may prove to be the definitive treatment option for such patients.  相似文献   
5.
6.
7.
8.
Individuals with sudden unilateral deafness offer a unique opportunity to study plasticity of the binaural auditory system in adult humans. Stimulation of the intact ear results in increased activity in the auditory cortex. However, there are no reports of changes at sub-cortical levels in humans. Therefore, the aim of the present study was to investigate changes in sub-cortical activity immediately before and after the onset of surgically induced unilateral deafness in adult humans. Click-evoked auditory brainstem responses (ABRs) to stimulation of the healthy ear were recorded from ten adults during the course of translabyrinthine surgery for the removal of a unilateral acoustic neuroma. This surgical technique always results in abrupt deafferentation of the affected ear. The results revealed a rapid (within minutes) reduction in latency of wave V (mean pre = 6.55 ms; mean post = 6.15 ms; p < 0.001). A latency reduction was also observed for wave III (mean pre = 4.40 ms; mean post = 4.13 ms; p < 0.001). These reductions in response latency are consistent with functional changes including disinhibition or/and more rapid intra-cellular signalling affecting binaurally sensitive neurons in the central auditory system. The results are highly relevant for improved understanding of putative physiological mechanisms underlying perceptual disorders such as tinnitus and hyperacusis.  相似文献   
9.
10.
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