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   4535篇
  免费   316篇
  国内免费   83篇
耳鼻咽喉   9篇
儿科学   175篇
妇产科学   45篇
基础医学   446篇
口腔科学   172篇
临床医学   727篇
内科学   826篇
皮肤病学   330篇
神经病学   424篇
特种医学   378篇
外科学   433篇
综合类   136篇
一般理论   3篇
预防医学   265篇
眼科学   23篇
药学   357篇
肿瘤学   185篇
  2023年   19篇
  2022年   27篇
  2021年   57篇
  2020年   53篇
  2019年   76篇
  2018年   78篇
  2017年   79篇
  2016年   74篇
  2015年   80篇
  2014年   90篇
  2013年   144篇
  2012年   171篇
  2011年   212篇
  2010年   194篇
  2009年   138篇
  2008年   187篇
  2007年   214篇
  2006年   176篇
  2005年   164篇
  2004年   141篇
  2003年   148篇
  2002年   154篇
  2001年   132篇
  2000年   130篇
  1999年   136篇
  1998年   130篇
  1997年   118篇
  1996年   133篇
  1995年   113篇
  1994年   106篇
  1993年   98篇
  1992年   92篇
  1991年   97篇
  1990年   88篇
  1989年   94篇
  1988年   95篇
  1987年   69篇
  1986年   85篇
  1985年   86篇
  1984年   52篇
  1983年   45篇
  1982年   34篇
  1981年   31篇
  1980年   36篇
  1979年   23篇
  1978年   25篇
  1977年   31篇
  1976年   27篇
  1975年   23篇
  1973年   11篇
排序方式: 共有4934条查询结果,搜索用时 15 毫秒
51.
Malondialdehyde (MDA) is a product of lipid peroxidation and prostaglandin biosynthesis. It is mutagenic and carcinogenic and the major adduct formed by reaction with DNA, a highly fluorescent pyrimidopurinone (M1-dG), has been detected in healthy human liver and leukocyte DNA. Analytical methods used so far for the detection of M1- dG have not been applied to a large number of individuals or variety of samples. Often, only a few microg of DNA from human tissues are available for analysis and a very sensitive assay is needed in order to detect background levels of M1-dG in very small amounts of DNA. In this paper, the development of an immunoslot blot (ISB) assay for the measurement of MI-dG in 1 microg of DNA is described. The limit of detection of the assay is 2.5 adducts per 10(8) bases. A series of human samples were analysed and levels of 5.6-9.5 (n = 8) and 3.1-64.3 (n = 42) of M1-dG per 10(8) normal bases were detected in white blood cell and gastric biopsy DNA, respectively. Results on four human samples were compared with those obtained using an HPLC/32P-post- labelling (HPLC/PPL) method previously developed and indicated a high correlation between M1-dG levels measured by the two assays. The advantages of ISB over other assays including HPLC/PPL, such as the possibility of analysing 1 microg DNA/sample and the fact that it is less time-consuming and laborious, means that it can be more easily used for routine analysis of a large number of samples in biomonitoring studies.   相似文献   
52.
53.
Young adults living with type 1 diabetes often struggle to achieve what clinicians consider to be optimal levels of metabolic control. Despite the impact that this can have on a young person''s future risk of complications, there are relatively few studies reporting new ways of organizing or delivering care to this cohort. In this article, we explore some of the reasons why young adult diabetes care is challenging, and describe approaches to “re‐imagining” how care might be improved. The work is informed by the ‘Making Care Fit’ collaborative and by a program of research, entitled D1 Now, involving co‐design of a complex person‐centered intervention with young adults.  相似文献   
54.
The Carleton University Responsiveness to Suggestion Scale (CURSS) of Spanos, Radtke, Hodgins, Bertrand 3 and Stam and Spanos, Radtke, Hodgins, Stam, and Bertrand (1983) was individually administered to a sample of 61 facial pain patients. The mean scores on the 3 CURSS suggestibility dimensions were higher than those of the college student norms. As in previous studies using the CURSS, however, objective scores were smaller when experienced involuntariness was taken into account. Observer scores of overt responses were highly related to self-scores of overt responses. The CURSS also proved a good predictor of reductions in clinical pain following a psychologically based treatment program.  相似文献   
55.
56.
57.
58.
59.
van Schaik  JP; Hawkins  IF  Jr 《Radiology》1985,155(3):829-830
A new technique is described for reversing the direction of the catheter tip during translumbar aortography, without the need for partial withdrawal of the catheter from the aortic lumen. The method ensures optimal delivery of contrast medium at the desired level, while avoiding the risk of retroperitoneal bleeding or dislodgement during catheter manipulation.  相似文献   
60.
Minactivin expression in human monocyte and macrophage populations   总被引:4,自引:0,他引:4  
Adherent monolayer cultures of human blood monocytes, peritoneal macrophages, bone marrow macrophages, and colonic mucosa macrophages were examined for their ability to produce and secrete minactivin, a specific inactivator of urokinase-type plasminogen activator. All except colonic mucosa macrophages produced and secreted appreciable amounts of minactivin, but only blood monocytes were stimulated by muramyl dipeptide (adjuvant peptide) to increase production. The minactivin from each of these populations could be shown to preferentially inhibit urokinase-type plasminogen activator and not trypsin, plasmin, or "tissue"-type plasminogen activator (HPA66). A plasminogen-activating enzyme present in monocyte cultures appeared unaffected by the presence of minactivin and could be shown to be regulated independently by dexamethasone.  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