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   1314964篇
  免费   87851篇
  国内免费   2649篇
耳鼻咽喉   17936篇
儿科学   40131篇
妇产科学   33332篇
基础医学   186397篇
口腔科学   34931篇
临床医学   117689篇
内科学   252990篇
皮肤病学   28579篇
神经病学   103705篇
特种医学   51807篇
外国民族医学   214篇
外科学   199074篇
综合类   25088篇
现状与发展   4篇
一般理论   562篇
预防医学   94802篇
眼科学   29578篇
药学   103629篇
  8篇
中国医学   3720篇
肿瘤学   81288篇
  2021年   12496篇
  2019年   11941篇
  2018年   16288篇
  2017年   12845篇
  2016年   14738篇
  2015年   17265篇
  2014年   23528篇
  2013年   33470篇
  2012年   47068篇
  2011年   49575篇
  2010年   28888篇
  2009年   26626篇
  2008年   45311篇
  2007年   47884篇
  2006年   47607篇
  2005年   46206篇
  2004年   44091篇
  2003年   41798篇
  2002年   40122篇
  2001年   62369篇
  2000年   63389篇
  1999年   53269篇
  1998年   15266篇
  1997年   13448篇
  1996年   13197篇
  1995年   12239篇
  1994年   11090篇
  1993年   10474篇
  1992年   39101篇
  1991年   37508篇
  1990年   36864篇
  1989年   35322篇
  1988年   31954篇
  1987年   31086篇
  1986年   29255篇
  1985年   27598篇
  1984年   20660篇
  1983年   17541篇
  1982年   10570篇
  1981年   9260篇
  1979年   17859篇
  1978年   12365篇
  1977年   11142篇
  1976年   9677篇
  1975年   10756篇
  1974年   12339篇
  1973年   11873篇
  1972年   11193篇
  1971年   10449篇
  1970年   9599篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
871.
Book Reviews     
Book reviewed in this articles: Essential Paediatric Dermatology . By J, Verbov Skin Disorders in the Elderly . Edited by B. E. Monk , R. A. C. Graham  相似文献   
872.
The effect of apomorphine on regional cerebral blood flow in schizophrenia   总被引:1,自引:0,他引:1  
A double-blind, placebo-controlled crossover study of the effects of apomorphine on regional cerebral blood flow (rCBF) during a prefrontal cortex activation task was undertaken to explore the role of dopamine on cortical function. The subjects were eight drug-free, chronically psychotic patients; six patients had schizophrenia. In each, apomorphine increased the relative prefrontal flow. The results suggest that enhanced prefrontal dopamine activity may reverse deficits in prefrontal cortex metabolism in schizophrenia.  相似文献   
873.
874.
Glucocorticoid effects on kainic acid-induced motor seizures and wet dog shakes in rats were investigated by adrenalectomy and dexamethasone treatment. One-day adrenalectomy attenuated kainic acid-induced wet dog shakes and seizure activity. These effects were restored by dexamethasone. Administration of dexamethasone to non-adrenalectomized rats potentiated kainic acid-induced wet dog shakes and severity of seizure activity. These results suggest that glucocorticoids may play an important role in modulating the severity of kainic acid-induced seizures and wet dog shakes.  相似文献   
875.
M E Eichler  K M Rich 《Brain research》1989,482(2):340-346
The time course of dependence on nerve growth factor (NGF) for survival in sensory neurons in vitro was examined with microscopic and biochemical methods. Primary dorsal root ganglion (DRG) cultures from embryonic-day-15 (E-15) and day-19 (E-19) rats were maintained with standard dissociated cell culture techniques in the absence of most non-neuronal cells. After various times in culture, neurons were acutely deprived of neurotrophic support by changing to NGF-free medium and adding NGF antiserum to eliminate any residual NGF. Neuronal cultures were examined with phase microscopy; and, their metabolic activity was measured with a protein assay at various time points after NGF deprivation. E-15 neurons grown in culture for 5 days were exquisitely sensitive to acute NGF deprivation. By 12 h after NGF deprivation, neuronal morphology was severely disrupted and the majority of neurons appeared dead. E-15 neurons grown in culture for 8 or 11 days showed progressively less dependence on NGF for survival. These older neurons did not die until 24 and 48 h, respectively, following NGF withdrawal. Neurons grown in culture for 20 days did not show any morphologic changes by phase microscopy up to 4 days after NGF deprivation. Protein incorporation progressively decreased between 12 and 48 h after NGF withdrawal in E-15 neurons grown in culture for 5, 8, or 11 days.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
876.
877.
Modern identification of Neisseria gonorrhoeae may be either accomplished by direct detection of gonococcal antigen, i.e. without microbiological culturing, or, following culturing, by rapid culture confirmation. The direct detection of gonococcal antigen in an enzyme immuno-assay (Gonozyme) shows reduced specifity especially with mixed microbial flora, and decreased sensitivity with small numbers of organisms. Culture confirmation may be achieved by a rapid sugar degradation test (API----quadFERM+), by specific enzyme detection using chromogenic substrates (Gonochek II), or by demonstration of protein I specific for Neisseria gonorrhoeae by means of monoclonal antibodies (Mikrotrak, Phadebact monoclonal GC, Gonogen II). Detection of protein I is highly sensitive and specific in both the tests of immunofluorescence and coagglutination.  相似文献   
878.
879.
880.
An ELISA technique has been developed to detect HBsAg in the sera of leprosy patients. Out of ninety-two serum samples taken from untreated leprosy patients, 10 samples were positive for HBsAg. The ELISA used in the present investigation is a low cost, reliable and sensitive marker of HBsAg. It is better than lesser sensitive (haemagglutination and counterimmunoelectrophoresis), costly and hazardous (radioimmunoassay) techniques and is therefore recommended for routine use.  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