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   63569篇
  免费   6690篇
  国内免费   4839篇
耳鼻咽喉   493篇
儿科学   628篇
妇产科学   599篇
基础医学   7429篇
口腔科学   1228篇
临床医学   8553篇
内科学   10018篇
皮肤病学   628篇
神经病学   3562篇
特种医学   2397篇
外国民族医学   52篇
外科学   6442篇
综合类   11147篇
现状与发展   19篇
一般理论   5篇
预防医学   4425篇
眼科学   1872篇
药学   6909篇
  39篇
中国医学   3429篇
肿瘤学   5224篇
  2024年   267篇
  2023年   1169篇
  2022年   2723篇
  2021年   3416篇
  2020年   2603篇
  2019年   2241篇
  2018年   2253篇
  2017年   2088篇
  2016年   1980篇
  2015年   2985篇
  2014年   3702篇
  2013年   3165篇
  2012年   4893篇
  2011年   5276篇
  2010年   3136篇
  2009年   2421篇
  2008年   3350篇
  2007年   3238篇
  2006年   3160篇
  2005年   3114篇
  2004年   2029篇
  2003年   1973篇
  2002年   1632篇
  2001年   1395篇
  2000年   1438篇
  1999年   1653篇
  1998年   1026篇
  1997年   995篇
  1996年   721篇
  1995年   668篇
  1994年   663篇
  1993年   414篇
  1992年   581篇
  1991年   436篇
  1990年   401篇
  1989年   344篇
  1988年   336篇
  1987年   265篇
  1986年   231篇
  1985年   195篇
  1984年   102篇
  1983年   68篇
  1982年   52篇
  1981年   49篇
  1980年   26篇
  1979年   45篇
  1978年   22篇
  1977年   28篇
  1976年   14篇
  1975年   11篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Single or combined monoclonal antibodies (McAbs) Zh53, Zh820, and Zh2-1 have been used to eliminate malignant clonogenic cells from human bone marrow. The test of cytotoxicity showed that all of these McAbs could express high specific cytotoxic action against HL-60 cells and were selectively complement-dependent cytotoxic to various types of fresh leukemic cells. Clonogenic assay detected that single treatment with antibody and rabbit complement (RC) could reduce clonogenic units of HL-60 cells by more than 2 logs and two treatments reduced clonogenic units by more than 4 logs. However, combination of 2 McAbs could reduce clonogenic units by 4-5 logs. The data suggest that multiple treatments with McAbs and RC or a combination of 2 McAbs are more effective than a single treatment in eliminating clonogenic tumor cells. Treatment of normal human bone marrow with Zh53, Zh2-1 and RC did not produce a loss of normal CFU-GM, but treatment with Zh820 reduced the clonic units of normal CFU-GM by 24%.
  相似文献   
12.
文章从医院人性化管理的定义,僵硬制度化管理的弊端,医院人性化管理的作用,怎样人性化管理职工和患者,阐明了如何实现医院人性化管理的问题。  相似文献   
13.
Neurotropin (NSP) is an extract isolated from the skin of rabbits inoculated with vaccinia virus. The present study examines the possible action of NSP on the number and function of immunocompe tent cells in mice. The experiment showed that NSP had no effect on both T and B lymphocytes of nor- malimmunized mouse spleen. The degree of plaque forming cell reaction and titre of specific antibody showed no significant differences when the NSP treated group and controls were compared. How- ever, NSP exhibited promotive effect on specific antigen binding cells in the early stage of immune responses. It was also noted that the rosette forming capacity of human T lymphocytes in vitro was restor- ed markedly by NSP. These results suggest that NSP possesses certain immunostimulating activity, particularly on the specific antigen binding cells and human T lymphocytes.  相似文献   
14.
X Dong  M He  X Song  B Lu  Y Yang  S Zhang  N Zhao  L Zhou  Y Li  X Zhu  R Hu 《Diabetic medicine》2007,24(12):1482-1486
AIMS: Our aim was to assess performances of the Cockcroft-Gault and simplified Modification of Diet in Renal Disease (MDRD) formulae in estimating glomerular filtration rate (GFR) in Chinese diabetic populations and their association with vascular risks. METHODS: A total of 1009 patients with Type 2 diabetes were categorized into low estimated GFR groups (GFR < 60 ml/min/1.73 m(2)) and control groups by the two equations. The performances of these formulae were assessed at different stages of kidney function. Carotid artery intima-media thickness (IMT) and the prevalence of diabetic retinopathy or albuminuria were compared among the groups. The ability of these formulae to identify established vascular risk markers using sensitivity, specificity, positive and negative predictive values were also compared. RESULTS: The prevalence of low estimated GFR was 32.7% with the Cockcroft-Gault formula and 5.2% with the MDRD formula, respectively. In low estimated GFR subjects by the MDRD formula, IMT was significantly thicker than those by the Cockcroft-Gault formula (1.2 mm vs. 1.0 mm; P < 0.05), with a higher prevalence of albuminuria (78.4 vs. 52.8%, P < 0.05) and diabetic retinopathy (46.5 vs. 30.5%; P < 0.05). The Cockcroft-Gault formula gave a specificity of 71.7% and a sensitivity of 37.0%, and the MDRD formula gave a specificity of 96.6% and a sensitivity of 7.9% in estimating low GFR relevant for established vascular risks. CONCLUSIONS: These formulae performed differently in Chinese diabetic populations. The simplified MDRD formula is minimally superior to the Cockcroft-Gault formula for its high specificity and positive predictive values in estimating low GFR relevant for vascular risks.  相似文献   
15.
以曼氏血吸虫的虫卵和成虫免疫家兔后所产生的特异性抗体,可用以日本血吸虫虫卵、尾蚴和成虫为抗原分别进行的COP,CHR和ELACIEP测出,表明两种人体血吸虫存有显著的交叉抗原成分。应用此种血清交叉反应性,以检测抗异种人体血吸虫的抗体,似有效而可取的,可用以辅助诊断援外回国人员是否感染国外人体血吸虫病。  相似文献   
16.
Abstract: The aim of this study was to evaluate in vitro the dose‐dependent induction potential of six commonly used trade herbal products on CYP2C19 and CYP2E1 metabolic activities in cultured human hepatocytes. S‐mephenytoin and chlorzoxazone were used as specific CYP substrates, respectively, and rifampicin was used as a positive induction control for both enzymes. The hepatocytes were exposed to herbal extracts in increasing and biological relevant concentrations for 72 hrs and CYP substrate metabolites were quantified by validated HPLC methodologies. The major findings were that St John's wort was the most potent CYP‐modulating herb, showing a dose‐dependent induction/inhibition of both CYP2C19 and CYP2E1, with induction at low dosages and inhibition at higher. Ginkgo biloba showed an induction/inhibition profile towards CYP2C19 which was similar but weaker than that observed for St John's wort. If cooperative mechanisms are involved is still an open question. Common sage induced CYP2C19 in a log‐linear dose‐dependent manner with increasing concentrations. Common valerian was a weak inducer of CYP2C19, while horse chestnut and cone flower were characterized as non‐inducers of CYP2C19. Only St John's wort showed an inductive effect towards CYP2E1. In addition to St John's wort, Gingko biloba and common sage should be considered as possible candidates for clinically relevant drug‐herb interactions with selected CYP2C19 substrates.  相似文献   
17.
我们自2000年10月至2008年12月采用大承气汤加黄连应用与肛周常见疾病术后病人,治疗其术后大小便潴留,里急后重等症状,取得了满意的疗效,现报告如下.  相似文献   
18.
8年间剖宫产率及指证变化的临床分析   总被引:3,自引:1,他引:2  
胡晓玲 《护理研究》2007,21(1):237-237
近年来,我国各地的剖宫产率均呈明显的上升趋势,部分地区的剖宫产率甚至高达60%。居高不下的剖宫产率已引起了广大产科工作者和全社会的广泛关注。对我院近8年来剖宫产病例的临床资料进行回顾性分析,以寻求剖宫产率逐年上升的原因及探讨降低剖宫产率的途径与方法。  相似文献   
19.
20.
After a comprehensive rernew of the literature on syphilitic aortitis, Longcope, (1) stated in 1913; ": . . . the presence of spiro: chetes in these lesions, as might be expected, cannot by any means be constantly demonstrated with Levaaiti stain. . . . . . . That these organisms are ''Treponema pallidum seems almost certain thouS:h actual proof of such by culture from the arterial lesions, a most difficult task, or direct inoculation into animals, has not as yet been accomplished."  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