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   158773篇
  免费   10802篇
  国内免费   625篇
耳鼻咽喉   1772篇
儿科学   3905篇
妇产科学   2616篇
基础医学   20940篇
口腔科学   3389篇
临床医学   15560篇
内科学   33629篇
皮肤病学   3241篇
神经病学   14611篇
特种医学   6965篇
外国民族医学   14篇
外科学   25223篇
综合类   1959篇
一般理论   109篇
预防医学   11811篇
眼科学   3306篇
药学   10152篇
中国医学   238篇
肿瘤学   10760篇
  2023年   885篇
  2022年   1486篇
  2021年   3374篇
  2020年   2079篇
  2019年   3118篇
  2018年   3592篇
  2017年   2800篇
  2016年   3137篇
  2015年   3584篇
  2014年   5092篇
  2013年   6847篇
  2012年   10336篇
  2011年   11004篇
  2010年   6311篇
  2009年   6013篇
  2008年   9746篇
  2007年   10188篇
  2006年   10098篇
  2005年   10144篇
  2004年   9307篇
  2003年   8617篇
  2002年   8269篇
  2001年   2149篇
  2000年   1840篇
  1999年   2126篇
  1998年   1926篇
  1997年   1551篇
  1996年   1333篇
  1995年   1251篇
  1994年   1125篇
  1993年   1015篇
  1992年   1293篇
  1991年   1190篇
  1990年   1032篇
  1989年   973篇
  1988年   913篇
  1987年   885篇
  1986年   884篇
  1985年   868篇
  1984年   925篇
  1983年   796篇
  1982年   962篇
  1981年   860篇
  1980年   728篇
  1979年   654篇
  1978年   647篇
  1977年   534篇
  1976年   514篇
  1974年   517篇
  1973年   449篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
64.
65.
Seventy-four patients with impaired renal function were investigated by ultrasound. By assessing renal length, renal echogenicity and collecting system dilatation, one can establish whether renal function is impaired by chronic or acute renal changes or by obstructive changes.  相似文献   
66.
67.
68.
Ultrasensitive bright field in situ hybridization assays using enzyme metallography (EnzMet) have been developed and validated, but little is known regarding the applicability of EnzMet for immunophenotypic detection of protein via IHC. Superior resolution via discrete metallographic deposits offers the potential for enhancing high-resolution immunophenotyping. Using high-complexity tissue microarrays (TMAs), 88 common solid tumors were evaluated by automated EnzMet (Nanoprobes and Ventana). Targets were chosen to assess the ability of EnzMet to specifically localize encoded antigens in the nucleus (estrogen receptor), cytoplasm (cytokeratins), and cytoplasmic membrane (HER2) in TMAs. Results were compared with conventional IHC diaminobenzidine (DAB) immunostaining. There was full concordance between the EnzMet and conventional IHC results. Furthermore, the EnzMet reaction products did not appreciably diffuse, were dense and sharply defined, and provided excellent high-resolution differentiation of cellular compartments in paraffin sections for the nuclear, cytoplasmic, and cell membrane-localized antigens evaluated. The higher density of elemental silver deposited during enzyme metallography permitted evaluation of core immunophenotypes at a relatively low magnification, allowing more tissue to be screened in an efficient manner. This preliminary study shows the utility of using enzyme metallography for high-resolution immunophenotyping in TMAs.  相似文献   
69.
Alcohol and other drug (AOD) use behaviors of health professions students (HPS) were assessed by surveying both university-based HPS and other nursing programs in a Midwestern state in 1999. Response was 2,646 (56.4%) of surveyed students. Family history of alcohol-related and drug-related problems were reported by 39.8% and 13.9%, respectively, with 42.6% of respondents reporting one or both. Among nursing respondents, 48.1%, 19.2% and 51.1%, respectively, reported family problems with alcohol, drugs, or one or both. Past-year alcohol use was comparable to undergraduate college students (UCS) nationally (83%); heavy drinking, tobacco and recreational drug use by HPS were lower. Past year drug use was highest among medical students. Marijuana was the predominant illicit drug; medical students and males most often reported use. Health professions educational systems should proactively address student AOD prevention, education and assistance needs.  相似文献   
70.
Thomas Attig 《Death Studies》1991,15(4):385-393
Concepts of the grieving process as passive are rejected, and concepts of the process as active are embraced. Standard stage-phase and medical treatments of bereavement are based on the belief that grieving is experienced passively. The emotion of grief and the coping process of grieving are distinguished; the emotion is said to render the bereaved passive and the coping process is said to challenge the bereaved, presenting them with choices. Alternative concepts of the grieving process as an active one are reviewed, tasks that confront the bereaved are outlined, and grieving is discussed as being rich in choice. The importance of the latter concepts for promoting self-understanding and defining helping strategies is underscored.  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