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   29422篇
  免费   2295篇
  国内免费   50篇
耳鼻咽喉   275篇
儿科学   833篇
妇产科学   744篇
基础医学   3847篇
口腔科学   691篇
临床医学   3208篇
内科学   6294篇
皮肤病学   534篇
神经病学   2644篇
特种医学   972篇
外国民族医学   1篇
外科学   3907篇
综合类   255篇
现状与发展   1篇
一般理论   23篇
预防医学   2912篇
眼科学   408篇
药学   2141篇
中国医学   71篇
肿瘤学   2006篇
  2024年   49篇
  2023年   377篇
  2022年   173篇
  2021年   481篇
  2020年   543篇
  2019年   617篇
  2018年   1048篇
  2017年   1012篇
  2016年   993篇
  2015年   812篇
  2014年   859篇
  2013年   1674篇
  2012年   2226篇
  2011年   2380篇
  2010年   1082篇
  2009年   660篇
  2008年   1920篇
  2007年   1921篇
  2006年   1836篇
  2005年   1673篇
  2004年   1522篇
  2003年   1478篇
  2002年   1445篇
  2001年   890篇
  2000年   1001篇
  1999年   512篇
  1998年   170篇
  1997年   149篇
  1996年   122篇
  1995年   138篇
  1994年   115篇
  1993年   113篇
  1992年   106篇
  1991年   110篇
  1990年   85篇
  1989年   106篇
  1988年   110篇
  1987年   94篇
  1986年   91篇
  1985年   139篇
  1984年   146篇
  1983年   103篇
  1982年   102篇
  1981年   75篇
  1980年   71篇
  1979年   81篇
  1978年   56篇
  1977年   47篇
  1976年   33篇
  1975年   27篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Schon in der frühen Phase der global sehr verschieden verlaufenden COVID-19-Pandemie zeigten sich Hinweise auf den Einfluss...  相似文献   
82.
83.
84.

Solitary sexual activity is a free, safe, and accessible way to experience sexual pleasure. Despite these advantages, research on masturbation in later life is highly understudied. Using data from a cross-sectional probability-based survey of 3816 European adults (mean age 67 years; range 60–75 years), we explored several sociodemographic, health, attitudinal, and sexual behavioral factors associated with reported masturbation frequency. Across all countries, between 41% and 65% of men and 27% and 40% of women reported any masturbation in the preceding month. Satisfaction with sexual activity and attitudes related to disapproval of sex without love were significant predictors of reported masturbation in almost all countries and in both genders. Age, education, self-perceived health, and depression were for the most part predictive of men’s reported masturbation, but not women’s. Generally, those believing sex is beneficial to older people were more likely to masturbate, while less permissive attitudes decreased the likelihood of reporting masturbation. To improve healthy sexual aging, misinformation about masturbation and sexual attitudes in older people need to be addressed.

  相似文献   
85.
86.
87.
European Journal of Epidemiology -  相似文献   
88.
A modified multiplex PCR method for detection of nine Staphylococcus aureus enterotoxin genes (sea, seb, sec, sed, see, seg, seh, sei, and sej) and one form of immunoreactive toxic shock syndrome toxin based on a previously published method (S. R. Monday and G. A. Bohach, J. Clin. Microbiol. 37:3411-3414, 1999) has been developed. The modified PCR protocol seems robust and gives reliable results.  相似文献   
89.
Muscle hypertrophy was induced in the soleus muscle of young rats by tenotomy of the gastrocnemius and plantaris muscles. Three and 7 days afterwards the sciatic nerve was sectioned. The loss of weight of muscles subjected to this combined procedure three days after denervation was 30–40%. Lysosomal enzyme activities (acid phosphatase, -glucosidase, -galactosidase and N-acetyl--d-glucosaminidase) and energy enzyme activities (lactate dehydrogenase, LDH, triose-3-phosphate dehydrogenase, TPDH,d-hexokinase, HK and citrate synthase, CS) were determined 3 days after denervation, 3, 7 and 10 days after hypertrophy had been induced and 3 days after denervation of hypertrophying muscles on day 3 and 7. Normal non-operated rats of corresponding body wieght served as controls and their enzyme activities were estimated on the same day. In the course of muscle hypertrophy, the 4 lysosomal enzyme activities increased progressively. Although 3 days' denervation of control muscles did not alter lysomal enzyme activities, denervation of hypertrophying muscles greatly enhanced the activity of these enzymes. Enzymes of energy metabolism were affected to a lesser degree. The results suggest that denervation of hypertrophying muscles causes more extreme changes in muscle weight and lysosomal enzyme activities than denervation alone. The possible implications of this finding are discussed in relation to the rapid atrophy.  相似文献   
90.
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