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   61719篇
  免费   5713篇
  国内免费   3426篇
耳鼻咽喉   522篇
儿科学   885篇
妇产科学   1060篇
基础医学   7161篇
口腔科学   1083篇
临床医学   7217篇
内科学   9956篇
皮肤病学   739篇
神经病学   2946篇
特种医学   2536篇
外国民族医学   34篇
外科学   7443篇
综合类   9068篇
现状与发展   15篇
一般理论   16篇
预防医学   3989篇
眼科学   1499篇
药学   6533篇
  53篇
中国医学   3087篇
肿瘤学   5016篇
  2024年   177篇
  2023年   845篇
  2022年   2086篇
  2021年   2878篇
  2020年   2072篇
  2019年   1895篇
  2018年   2041篇
  2017年   1814篇
  2016年   1807篇
  2015年   2503篇
  2014年   3175篇
  2013年   3196篇
  2012年   4473篇
  2011年   4768篇
  2010年   3087篇
  2009年   2531篇
  2008年   3384篇
  2007年   3441篇
  2006年   3205篇
  2005年   2974篇
  2004年   2408篇
  2003年   2238篇
  2002年   2029篇
  2001年   1682篇
  2000年   1608篇
  1999年   1449篇
  1998年   778篇
  1997年   783篇
  1996年   631篇
  1995年   535篇
  1994年   463篇
  1993年   319篇
  1992年   514篇
  1991年   421篇
  1990年   397篇
  1989年   355篇
  1988年   283篇
  1987年   269篇
  1986年   222篇
  1985年   167篇
  1984年   119篇
  1983年   90篇
  1982年   63篇
  1981年   77篇
  1980年   43篇
  1979年   83篇
  1978年   44篇
  1974年   37篇
  1972年   42篇
  1934年   38篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
全同非典进行特死斗争过程中,医护人员表现出一种临危不惧、挺身而出、全力救治、不怕牺牲、恪尽职守、患者至上、竭诚服务、科学防治的“抗非典精神”值得宣传,学习和效法。  相似文献   
22.
The levels and temporal variations of surface ozone at a coastal site in East China during summer and autumn were analyzed and the influences of meteorological parameters on ozone were investigated. An inland city was chosen as a comparison site. The main results and conclusions of this study are: (1) ozone pollution, with a maximum 1 h concentration of 150.98 ppbv, was severe during summer and autumn at the coastal site; (2) the ozone level was obviously higher at the coastal site than that at the inland site in September; (3) besides temperature and solar radiation, sea-land breeze circulation is an important factor influencing the ozone level at the coastal site, and sea breeze often induce high ozone levels (the average ozone concentration for sea breeze was about 13 ppbv higher than that for land breeze).  相似文献   
23.
目的 探究注意缺陷多动障碍儿童初始沙盘游戏特征.方法 对29名注意缺陷多动障碍儿童和29名正常儿童进行沙盘游戏干预,对照分析两组儿童初始沙盘游戏主题及沙具使用情况.结果 注意缺陷多动障碍儿童沙盘游戏主题较正常儿童混乱无序,两组比较差异有统计学意义(χ2=22.58,P<0.00);两组儿童在沙具使用方面比较差异无统计学意义(均P>0.05).结论 注意缺陷多动障碍儿童沙盘游戏具有独特特征以及一定的临床诊断筛查价值.  相似文献   
24.
HPLC法测定双红活血胶囊中黄芪甲苷的含量   总被引:2,自引:0,他引:2  
目的 测定双红活血胶囊中黄芪甲苷的含量。方法 采用高效液相色谱 (HPLC)法测定。结果 平均回收率为 1 0 0 .6%,CV =1 .62 %。结论 该方法简便 ,准确  相似文献   
25.
26.
27.
An immunofluorescent (IF) method that detects Burkholderia pseudomallei in clinical specimens within 10 min was devised. The results of this rapid method and those of an existing IF method were prospectively compared with the culture results for 776 specimens from patients with suspected melioidosis. The sensitivities of both IF tests were 66%, and the specificities were 99.5 and 99.4%, respectively.  相似文献   
28.
BACKGROUND: Oral submucous fibrosis (OSF) is a chewing habit-related pre-cancerous condition of the oral mucosa affecting predominantly south Asians. It is histopathologically characterized by epithelial atrophy and fibrosis of the subepithelial connective tissue. Fibrosis extends all the way into the muscle layer, leading to difficulty in mouth opening. However, the dynamics of extracellular matrix (ECM) remodeling with OSF progression is largely unknown. METHODS: Forty biopsy specimens of OSF and 10 of normal buccal mucosa were examined for expression/deposition modes of eight ECM molecules by histochemistry, immunohistochemistry, and in situ hybridization. RESULTS: In the early stage of OSF, tenascin, perlecan, fibronectin, collagen type III were characteristically enhanced in the lamina propria and the submucosal layer. In the intermediate stage, the ECM molecules mentioned above and elastin were extensively and irregularly deposited around muscle fibers. In the advanced stage, such ECM depositions decreased and were entirely replaced with collagen type I only. Their gene expression levels varied with progression of fibrosis, but the mRNA signals were confirmed in fibroblasts in the submucosal fibrotic areas. CONCLUSIONS: The results indicate that the ECM remodeling steps in OSF are similar to each phase of usual granulation tissue formation. Restricted mouth opening may be a result of loss of variety of ECM molecules including elastin into the homogeneity of collagen type I replacing muscle fibers.  相似文献   
29.
30.
Although many monoclonal antibodies have been made in human colon cancer, none of them are from the Chinese species. Recently, a colon cancer cell line CC-M2 established from a Chinese patient has been completely characterized and used as immunogen to produce monoclonal antibodies. Monoclonal antibodies were produced by standard hybridoma technique. The fusion rate was 95.8%. An isotype IgG1 of high proliferation named as Sam-2 was used in this study. The titers were measured around 10(4). Further studies on MoAb Sam-2 through indirect immunofluorescent and immunoperoxidase tests revealed its good specificity and sensitivity in colorectal cancer tissue. In CEA study, the result indicated that Sam-2 may react on a non-CEA related antigen. For further clinical application, the antigen was identified as a glycoprotein by chemical resistant test. In preliminary studies using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting techniques, Sam-2 could recognize two closed antigens or a dimer antigen with molecular weight 25.2 and 27 Kd respectively.  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