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   3808篇
  免费   81篇
  国内免费   13篇
耳鼻咽喉   10篇
儿科学   146篇
妇产科学   128篇
基础医学   235篇
口腔科学   107篇
临床医学   748篇
内科学   899篇
皮肤病学   211篇
神经病学   118篇
特种医学   11篇
外科学   446篇
综合类   26篇
一般理论   29篇
预防医学   254篇
眼科学   67篇
药学   392篇
肿瘤学   75篇
  2016年   28篇
  2015年   35篇
  2014年   37篇
  2013年   77篇
  2012年   26篇
  2010年   95篇
  2009年   109篇
  2008年   35篇
  2006年   28篇
  2005年   28篇
  2003年   26篇
  2001年   47篇
  1999年   93篇
  1998年   153篇
  1997年   193篇
  1996年   190篇
  1995年   126篇
  1994年   162篇
  1993年   120篇
  1992年   116篇
  1991年   110篇
  1990年   100篇
  1989年   113篇
  1988年   119篇
  1987年   99篇
  1986年   96篇
  1985年   83篇
  1984年   83篇
  1983年   93篇
  1982年   83篇
  1981年   77篇
  1980年   70篇
  1979年   90篇
  1978年   79篇
  1977年   41篇
  1976年   40篇
  1975年   39篇
  1974年   38篇
  1973年   24篇
  1971年   41篇
  1970年   32篇
  1969年   28篇
  1968年   43篇
  1967年   35篇
  1966年   30篇
  1965年   34篇
  1964年   25篇
  1963年   31篇
  1962年   31篇
  1959年   23篇
排序方式: 共有3902条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
95.
Based on the international literature and the author's experience of carrying out studies of postnatal depression (PND) in Uganda, Scotland and England this paper describes the core components of Culture relevant for a full understanding of the prevention and management of PND.These include culturally sanctioned postnatal rituals as well as other social influences that determine the pathway to care and choice of therapy.The field of perinatal psychiatry is outlined with regard to the specific skills knowledge and attitudes required to practise this sub-specialty.The paper concludes by discussing the possible effect of changing patterns of family life on the transmission of knowledge values and beliefs between generations and the effect of these changes on the status of childbearing and the experience of postnatal depression.  相似文献   
96.
97.
98.
This study investigates severity of dependence upon heroin, cocaine and amphetamines in a group of 200 heroin users, 75% of whom were not in contact with any treatment agency. For drug takers who were current users of more than one drug, heroin produced more severe dependence than either cocaine or amphetamine and many users of these stimulant drugs reported having experienced no problems of dependence. Severity of dependence was influenced by route of administration as welt as type of drug. Heroin taken by injection was associated with more severe dependence than smoked heroin. For cocaine, injection and smoking were associated with equivalent dependence ratings, and both of these routes were associated with more severe dependence than cocaine used intranasally. For amphetamine, there were no differences in severity of dependence ratings for injection, intranasal or oral use. Severity of dependence was correlated with dose and duration of drug use; it was also associated with previous attendance at a drug treatment agency, though dependence problems were also common among heroin users who had never received treatment. Implications of these findings are discussed.  相似文献   
99.
P-selectin (also called CD62, GMP-140, PADGEM, CD62P) is a recently described member of a family of vascular adhesion receptors expressed by activated platelets and endothelial cells that are involved in leucocyte cell adhesion. The aim of this study was to characterize a new monoclonal antibody (LYP7) directed against activated human blood platelets that inhibits ristocetin-induced platelet aggregation. Immunoadsorbent affinity chromatography and immunoprecipitation studies showed that LYP7 (IgG1) bound a surface-labelled glycoprotein (GP) which changed its apparent molecular mass (Mr) on reduction from 138 kD (situated below GPIIb) to 148 kD (above GPIIbα). LYP7 and S12, a monoclonal antibody directed against P-selectin immunoprecipitated the same band. Using ELISA assay, purified P-selectin was shown to bind LYP7 and S12 monoclonal antibodies. Binding sites of 125I-labelled LYP7, which was greatly increased on thrombin-stimulated (2 U/ml) washed platelets (10825±2886, mean ±SD) (Kd=1.5±0.5 nm ) compared to resting platelets (2801±1278, mean ±SD) (Kd=1.5±0.6 nm ), was found to be normal on thrombin-stimulated platelets taken from a patient with grey platelet syndrome or a patient with Glanzmann thrombasthenia. LYP7 (IgG1, F(ab′)2 or Fab fragments) inhibited ristocetin-induced platelet aggregation of platelets in a dose-dependent fashion without affecting the binding of von Willebrand (vWf ) factor. However, agglutination of formaldehyde-fixed platelets induced by ristocetin was not affected by monoclonal antibody LYP7. In addition, the binding of thrombin-activated platelets to neutrophils was inhibited by monoclonal antibody LYP7. These results strongly suggest that P-selectin, by promoting cell–cell contact, may play an active role in platelet–platelet interactions.  相似文献   
100.
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