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   2422831篇
  免费   171884篇
  国内免费   3331篇
耳鼻咽喉   32581篇
儿科学   78612篇
妇产科学   63861篇
基础医学   355945篇
口腔科学   64077篇
临床医学   215979篇
内科学   472493篇
皮肤病学   52078篇
神经病学   192631篇
特种医学   91415篇
外国民族医学   489篇
外科学   366599篇
综合类   48171篇
现状与发展   12篇
一般理论   848篇
预防医学   189428篇
眼科学   55094篇
药学   178637篇
  11篇
中国医学   4579篇
肿瘤学   134506篇
  2021年   18980篇
  2019年   19541篇
  2018年   35305篇
  2017年   27056篇
  2016年   30869篇
  2015年   25933篇
  2014年   36328篇
  2013年   54153篇
  2012年   77047篇
  2011年   86873篇
  2010年   52976篇
  2009年   48996篇
  2008年   82204篇
  2007年   88933篇
  2006年   80479篇
  2005年   79286篇
  2004年   76415篇
  2003年   74698篇
  2002年   71433篇
  2001年   108975篇
  2000年   111889篇
  1999年   93655篇
  1998年   27154篇
  1997年   23881篇
  1996年   24172篇
  1995年   22856篇
  1994年   21041篇
  1993年   19835篇
  1992年   72104篇
  1991年   70190篇
  1990年   68501篇
  1989年   65751篇
  1988年   60384篇
  1987年   59219篇
  1986年   55300篇
  1985年   53098篇
  1984年   39365篇
  1983年   33454篇
  1982年   19937篇
  1979年   35958篇
  1978年   25703篇
  1977年   21245篇
  1976年   20392篇
  1975年   21817篇
  1974年   26171篇
  1973年   24806篇
  1972年   23200篇
  1971年   22038篇
  1970年   20271篇
  1969年   19342篇
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
1.
2.
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   
3.
4.
5.
The present study aimed at measuring seropositivities for infection by Ascaris suum and Toxocara canis using the excretory/secretory (E/S) antigens from Ascaris suum (AES) and Toxocara canis (TES) within an indigenous population. In addition, quantification of cytokine expressions in peripheral blood cells was determined. A total of 50 Warao indigenous were included; of which 43 were adults and seven children. In adults, 44.1% were seropositive for both parasites; whereas children had only seropositivity to one or the other helminth. For ascariosis, the percentage of AES seropositivity in adults and children was high; 23.3% and 57.1%, respectively. While that for toxocariosis, the percentage of TES seropositivity in adults and children was low; 9.3% and 14.3%, respectively. The percentage of seronegativity was comparable for AES and TES antigens in adults (27.9%) and children (28.6%). When positive sera were analyzed by Western blotting technique using AES antigens; three bands of 97.2, 193.6 and 200.2 kDas were mostly recognized. When the TES antigens were used, nine major bands were mostly identified; 47.4, 52.2, 84.9, 98.2, 119.1, 131.3, 175.6, 184.4 and 193.6 kDas. Stool examinations showed that Blastocystis hominis, Hymenolepis nana and Entamoeba coli were the most commonly observed intestinal parasites. Quantification of cytokines IFN-γ, IL-2, IL-6, TGF-β, TNF-α, IL-10 and IL-4 expressions showed that there was only a significant increased expression of IL-4 in indigenous with TES seropositivity (p < 0.002). Ascaris and Toxocara seropositivity was prevalent among Warao indigenous.  相似文献   
6.
A 42‐year‐old man presented with a viral prodrome and tested positive for influenza A. He rapidly deteriorated developing cardiogenic shock, rhabdomyolysis, and acute kidney injury. Patient improved 1 week later with supportive measures including vasopressors, inotropes, and an intraaortic balloon pump. We report this case as it highlights the discordance between echocardiographic ventricular wall thickening as a result of myocardial edema, and electrocardiographic findings at presentation, with a reversal in findings at time of resolution. Additionally, there was some suggestion of a regional pattern to the reduced longitudinal strain.  相似文献   
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