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   1842篇
  免费   172篇
  国内免费   22篇
耳鼻咽喉   23篇
儿科学   66篇
妇产科学   14篇
基础医学   215篇
口腔科学   25篇
临床医学   262篇
内科学   376篇
皮肤病学   43篇
神经病学   136篇
特种医学   156篇
外科学   191篇
综合类   26篇
一般理论   1篇
预防医学   113篇
眼科学   11篇
药学   247篇
中国医学   1篇
肿瘤学   130篇
  2021年   36篇
  2020年   17篇
  2019年   27篇
  2018年   35篇
  2017年   24篇
  2016年   40篇
  2015年   39篇
  2014年   50篇
  2013年   65篇
  2012年   82篇
  2011年   77篇
  2010年   62篇
  2009年   65篇
  2008年   67篇
  2007年   96篇
  2006年   87篇
  2005年   89篇
  2004年   71篇
  2003年   65篇
  2002年   60篇
  2001年   61篇
  2000年   56篇
  1999年   44篇
  1998年   45篇
  1997年   45篇
  1996年   42篇
  1995年   41篇
  1994年   23篇
  1993年   29篇
  1992年   37篇
  1991年   21篇
  1990年   28篇
  1989年   33篇
  1988年   31篇
  1987年   30篇
  1986年   19篇
  1985年   29篇
  1984年   18篇
  1983年   18篇
  1982年   19篇
  1980年   17篇
  1978年   19篇
  1977年   10篇
  1976年   14篇
  1975年   14篇
  1971年   11篇
  1970年   13篇
  1969年   10篇
  1967年   12篇
  1966年   12篇
排序方式: 共有2036条查询结果,搜索用时 15 毫秒
1.
2.
麦冬类中药组织切片计算机三维重建图鉴   总被引:9,自引:0,他引:9  
利用计算机技术实现麦冬类中药组织连续切片三维重建与动态显示,为计算机辅助生药学鉴定和教学提供了新的三维图像技术和研究资料。  相似文献   
3.
用混合粘合剂碳糊电极测定丁螺环酮   总被引:6,自引:1,他引:5  
用混合粘合剂碳糊电极测定丁螺环酮张正奇,曾鸽鸣,刘传桂,黎艳飞(湖南大学化学化工系,长沙410082)碳糊电极无毒,制作方便,表面更新容易,应用电位范围广,在药物分析中已有应用[1~5]。我们在液体石腊中加入添加剂,组成混合粘合剂,可显著改善电极的检...  相似文献   
4.
5.
The aim of this review article is to discuss the electrocardiographic presentation of the so called variants of pre‐excitation (“Mahaim fibers”) during sinus rhythm and tachycardia.  相似文献   
6.
G S Bedi  N Back 《Hybridoma》1987,6(5):521-526
Five hybridoma cell lines were established that secrete monoclonal antibodies (MAbs) directed against rat plasma low molecular weight plasma kininogen. Two of the secreted antibodies were of the IgG1k isotype. The remaining three were of the IgG1 lambda, IgG2ak and IgMk isotypes, respectively. The dissociation constants (Kd) of these MAbs ranged from 0.58 X 10(-9) M to 5.4 X 10(-9) M. At least two distinct epitopes on the rat plasma kininogen were recognized by these MAbs. Further characterization of the MAbs showed that four MAbs cross-reacted strongly with kininogen from the Murphy-Sturm lymphosarcoma (MSLS) tumor while one of the MAbs cross-reacted weakly with MSLS tumor kininogen.  相似文献   
7.
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.  相似文献   
8.
Neuronal plasticity can manifest itself in alterations in the sensitivity of memory to the effects of drugs. After the production of a brain lesion, the memory processing of a passive-avoidance task in mice gradually becomes sensitive to the effect of morphine, i.e., an improvement in retention performance is seen after 6 weeks, but not after 1 or 2 weeks. The results presented demonstrate that, even if they lead to no discernible changes in behaviour, plastic processes can still be detected by means of behavioural tests.  相似文献   
9.
The serum concentrations of 3-keto-desogestrel have been measured in 43 women who took a low-dose oral contraceptive containing 30 micrograms ethinyl estradiol (CAS 57-63-6) together with 150 micrograms desogestrel (CAS 54024-22-5) for a period of 3 months. Basic pharmacokinetic parameters, like Cmax, tmax and AUC, as well as the serum protein binding of 3-keto-desogestrel were determined on days 1, 10 and 21 of the first and the third treatment cycle, respectively. During cycle one, Cmax, AUC(0-4h) and AUC(0-24h) values on day 1 were 1.9 +/- 0.7 ng/ml, 3.9 +/- 1.3 ng.ml-1.h and 12.4 +/- 5.7 ng.ml-1.h, respectively. These values increased to 4.7 +/- 2.0 ng/ml, 12.1 +/- 5.6 ng.ml-1.h and 47.3 +/- 26.0 ng.ml-1.h on day 21. Within cycle 3, a similar, although less steep increase was observed for these parameters and there was practically no difference in the values of corresponding parameters on day 21 of both cycles. Throughout treatment, there was a redistribution of 3-keto-desogestrel with respect to the binding proteins albumin and sex hormone binding globulin (SHBG). During cycle 1, the free fraction decreased from 1.8% on day 1 to 1.1% on day 21, and the SHBG-bound fraction increased at the same time from 40% to 62%, mainly at the expense of the albumin-bound fraction. During cycle 3, there were only minor changes as compared to cycle one. The observed changes in the serum protein binding were related to an increase in SHBG levels during the treatment period.  相似文献   
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