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   3570327篇
  免费   270237篇
  国内免费   8591篇
耳鼻咽喉   50449篇
儿科学   113030篇
妇产科学   96364篇
基础医学   501932篇
口腔科学   104044篇
临床医学   326354篇
内科学   690203篇
皮肤病学   75818篇
神经病学   289147篇
特种医学   138534篇
外国民族医学   1090篇
外科学   537046篇
综合类   87873篇
现状与发展   12篇
一般理论   1405篇
预防医学   281270篇
眼科学   85229篇
药学   266679篇
  32篇
中国医学   9067篇
肿瘤学   193577篇
  2018年   39230篇
  2017年   30007篇
  2016年   33109篇
  2015年   37998篇
  2014年   53659篇
  2013年   79839篇
  2012年   108843篇
  2011年   114798篇
  2010年   68161篇
  2009年   64186篇
  2008年   107116篇
  2007年   113849篇
  2006年   114679篇
  2005年   111076篇
  2004年   106888篇
  2003年   102552篇
  2002年   100035篇
  2001年   167609篇
  2000年   172664篇
  1999年   145362篇
  1998年   41511篇
  1997年   36995篇
  1996年   36623篇
  1995年   35411篇
  1994年   33055篇
  1993年   30578篇
  1992年   115049篇
  1991年   111358篇
  1990年   107449篇
  1989年   103793篇
  1988年   95850篇
  1987年   94131篇
  1986年   88988篇
  1985年   84862篇
  1984年   63903篇
  1983年   54447篇
  1982年   32269篇
  1981年   28822篇
  1979年   58873篇
  1978年   41129篇
  1977年   34936篇
  1976年   32716篇
  1975年   34515篇
  1974年   42467篇
  1973年   40516篇
  1972年   37930篇
  1971年   35024篇
  1970年   32903篇
  1969年   30606篇
  1968年   28111篇
排序方式: 共有10000条查询结果,搜索用时 2 毫秒
131.
Summary: The mosaic (Atp7a mo-ms ) is an X-linked, lethal mutation in mice. In mosaic mutant males, many clinical features characteristic of defective copper metabolism have been observed and they die at the age of 15 days, exhibiting strongsimilarities to the brindled and macular mutants. About 4% of the mutant males live to sexual maturity and some of them are fertile. In this paper, alterationsin the structure of the kidney from adult mutants are described. Owing to an inherited defect of efflux, copper is accumulated in the kidney of the mutants up to a toxic level and this leads to severe damage of the renal cortex. Pathological changes in the kidney mostly affected the structure of the renal corpuscle and renaltubules.  相似文献   
132.
133.
134.
OBJECTIVE: To determine whether under-reporting of rheumatic fever occurs at hospital, municipal, provincial and national levels of the South African health system. BACKGROUND: Information on the incidence of rheumatic fever (RF) and the prevalence of rheumatic heart disease (RHD) is required for the prevention of valvular heart disease in developing countries. In South Africa, RF was made a notifiable condition in 1989. It has recently been suggested that the reporting of RF cases may be incomplete, possibly because of underreporting by health care professionals and deficient administration of the disease notification system in South Africa. METHOD AND RESULTS: We assessed whether underreporting of RF cases occurs by comparing the numbers of RF cases reported per year at hospital, municipal, provincial and national levels from 1990 to 2004. There was a fall in the number of RF cases reported per year at national and provincial level over the 15 years of observation. A detailed analysis of the number of RF cases reported at hospital, municipal and provincial level for a 5-year period showed that more cases were diagnosed in one hospital (serving a smaller population) than were captured at municipal and provincial level (serving a larger population), suggesting underreporting by health care professionals. There were discrepancies in the number of cases reported at municipal, provincial and national level, suggesting poor administration of the notification system. CONCLUSION: There appears to be underreporting of RF cases by health care professionals, and poor administration of the RF notification system. Health care professionals need to be educated about the statutory requirement to notify all RF cases in South Africa. An effective national disease notification system is required.  相似文献   
135.
136.
137.
138.
139.
This article describes the proceedings of the 2006 Annual Meeting of the Fetal Alcohol Spectrum Disorders Study Group (FASDSG), which was held in Baltimore, Maryland on June 24, 2006. The meeting was held in conjunction with the annual meeting of the Research Society on Alcoholism and was supported by a grant from the National Institute on Alcohol Abuse and Alcoholism. The 2005-2006 FASDSG officers, Daniel J. Bonthius (President), Heather Carmichael Olson (Vice-President), and Jennifer Thomas (Secretary-Treasurer), organized the meeting. Nationally prominent speakers delivered plenary lectures on topics of newborn screening, ethics, and neuroscience. Selected members of the FASDSG provided brief scientific data (FASt) reports, describing new research findings. Representatives from national agencies involved in fetal alcohol syndrome (FAS) research, treatment, and prevention provided updates regarding priorities, funding, and agency activities. Presentations were also made by the 2006 Student Merit Award recipient and by the 2006 Rosett Award recipient. The meeting served as a forum for clinicians, neuroscientists, psychologists, social scientists, and other professionals to discuss recent advances in FAS research and to identify the most important gaps in the understanding of alcohol-induced teratology.  相似文献   
140.
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