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   2528篇
  免费   125篇
  国内免费   32篇
耳鼻咽喉   8篇
儿科学   95篇
妇产科学   20篇
基础医学   466篇
口腔科学   83篇
临床医学   296篇
内科学   564篇
皮肤病学   113篇
神经病学   90篇
特种医学   281篇
外科学   199篇
综合类   53篇
预防医学   93篇
眼科学   27篇
药学   156篇
中国医学   2篇
肿瘤学   139篇
  2018年   26篇
  2015年   32篇
  2014年   28篇
  2013年   88篇
  2012年   44篇
  2011年   33篇
  2010年   55篇
  2009年   36篇
  2008年   34篇
  2007年   65篇
  2006年   62篇
  2005年   49篇
  2004年   33篇
  2003年   40篇
  2002年   35篇
  2001年   39篇
  2000年   29篇
  1999年   50篇
  1998年   87篇
  1997年   97篇
  1996年   107篇
  1995年   73篇
  1994年   75篇
  1993年   77篇
  1992年   54篇
  1991年   48篇
  1990年   52篇
  1989年   73篇
  1988年   67篇
  1987年   57篇
  1986年   58篇
  1985年   43篇
  1984年   60篇
  1983年   33篇
  1982年   33篇
  1981年   40篇
  1980年   49篇
  1979年   26篇
  1978年   29篇
  1977年   37篇
  1976年   41篇
  1975年   37篇
  1972年   25篇
  1970年   23篇
  1965年   50篇
  1964年   50篇
  1963年   47篇
  1962年   41篇
  1961年   40篇
  1960年   65篇
排序方式: 共有2685条查询结果,搜索用时 0 毫秒
61.
62.
63.
杨解人  李庆平  饶曼人 《药学学报》1992,27(10):729-733
大鼠ip前胡丙素(Pra-C 15 mg/kg,bid×3d)和硝苯啶(Nif 60μg/kg,bid×3d),使离体缺血再灌注工作心脏的收缩(AP,LVSP,+dP/dtmax)舒张(-dP/dtmax LVEDP和T值)性能在35min时得到改善,尤以舒张性能改善明显,并能促进CO,CF,SV及HR恢复,改善心脏工作效率,减少CK释放和心肌线粒体钙含量,表明Pra-C和Nif对心肌缺血都有保护作用,Pra-C的效应与Nif相近。  相似文献   
64.
65.
The University of Oklahoma Medical Center has a comprehensive program of pediatric training, research and patient care. Establishment of the Oklahoma Health Center and its Children's Medical Center on the University campus will provide expanded opportunities for training and research in cooperation with other organizations concerned with child health and development.  相似文献   
66.
Stem Cell Migration and Proliferation During Severe Anemia   总被引:3,自引:2,他引:3  
The pluripotential stem cell (CFU) compartment of marrow and spleen wasevaluated in mice subjected to an intense erythroid stimulus associated withphenylhydrazine-induced anemia. Erythroid hyperplasia occurred in both marrow and spleen. CFU in the marrowgradually declined to approximately 50per cent of control levels (day 5) whiletheir numbers in the spleen increased(fourfold) by day 3 and were maintainedat this level for several days. Thesechanges in numbers of marrow andsplenic CFU were not associated withCFU proliferation. Thereafter, CFU inthe marrow, but not in the spleen, entered active cell cycle. The data suggestthat CFU migrate from marrow to spleenduring the demands of severe anemia.The induction of marrow CFU into cyclefurther suggests a negative feedback,which, perhaps through cell-cell interaction, maintains stem cells at a criticalcompartment size. The failure of splenicCFU to cycle may reflect the converseeffect, i.e. an inhibition on stem cell proliferation in the wake of an expandedstem cell pool.

Submitted on March 17, 1970 Revised on May 14, 1970 Accepted on June 9, 1970  相似文献   
67.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma   总被引:6,自引:3,他引:6  
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study.  相似文献   
68.
Thrombocytopoietic properties of oncostatin M   总被引:1,自引:2,他引:1  
Oncostatin M (OM) is a 28-kD glycoprotein that exhibits a panoply of biologic effects. Based on histologic observations of increased splenic megakaryocytes in nude mice implanted with an OM-secreting cell line, the thrombocytopoietic properties of OM in mice were investigated in culture and in vivo. Alone, OM did not induce megakaryocytic colony formation, but in combination with murine interleukin-3 (IL-3), OM markedly enhanced colony formation. The effects of OM on colony formation were similar to those of IL-6. OM alone augmented acetylcholinesterase in short-term marrow cultures. In normal mice, the administration of OM augmented platelet counts without increasing other circulating blood cell counts. The increment in counts exceeded that observed with IL-6. The kinetics of the OM response suggested that maximal increases in platelets occurred 3 days after the cessation of OM administration, irrespective of the duration of administration. In irradiated mice, OM administration accelerated platelet recovery and prevented the decrease in red blood cells observed in irradiated control animals. The data show that OM behaves as a megakaryocytic maturation factor in vitro and augments platelet production in vivo. Based on these animal data, OM may have potential clinical utility as a thrombocytopoietic agent.  相似文献   
69.
70.
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