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   3160934篇
  免费   232750篇
  国内免费   4901篇
耳鼻咽喉   44873篇
儿科学   103989篇
妇产科学   88159篇
基础医学   463677篇
口腔科学   88336篇
临床医学   282724篇
内科学   607953篇
皮肤病学   69148篇
神经病学   249709篇
特种医学   120108篇
外国民族医学   818篇
外科学   479303篇
综合类   66946篇
现状与发展   12篇
一般理论   1080篇
预防医学   245733篇
眼科学   74889篇
药学   237443篇
  12篇
中国医学   6176篇
肿瘤学   167497篇
  2018年   34180篇
  2017年   25686篇
  2016年   28881篇
  2015年   32742篇
  2014年   45960篇
  2013年   69472篇
  2012年   95684篇
  2011年   101944篇
  2010年   60598篇
  2009年   57118篇
  2008年   96511篇
  2007年   103100篇
  2006年   104226篇
  2005年   101416篇
  2004年   97286篇
  2003年   93817篇
  2002年   91281篇
  2001年   140769篇
  2000年   144407篇
  1999年   121786篇
  1998年   35910篇
  1997年   31611篇
  1996年   31975篇
  1995年   30094篇
  1994年   27912篇
  1993年   26245篇
  1992年   96030篇
  1991年   93911篇
  1990年   92057篇
  1989年   89060篇
  1988年   82306篇
  1987年   80795篇
  1986年   76419篇
  1985年   73272篇
  1984年   54730篇
  1983年   46852篇
  1982年   28178篇
  1981年   25217篇
  1979年   51200篇
  1978年   36409篇
  1977年   30776篇
  1976年   29308篇
  1975年   31925篇
  1974年   37938篇
  1973年   36369篇
  1972年   34348篇
  1971年   32395篇
  1970年   29980篇
  1969年   28671篇
  1968年   26649篇
排序方式: 共有10000条查询结果,搜索用时 16 毫秒
31.
32.
BackgroundThe aim of this study was to estimate the prevalence of dental prosthetic treatment and to investigate the demographic, social, economic and medical factors associated with the use of fixed and removable dentures in a representative sample of adults living in France.MethodsThe data were obtained from the 2002–2003 Decennial Health Survey, a cross-sectional study of a representative sample of the population living in France, which included 29,679 adults. Information was collected by interview. The variables collected were fixed denture, removable denture, age, gender, number of children, area of residence, nationality, educational attainment, family social status, employment status, annual household income per capita, supplementary insurance, chronic disease, eyesight problems/glasses, hearing problems/hearing aids. Multinomial logistic regression models were used to study the relationship between prosthetic treatment and demographic, socioeconomic and medical characteristics unadjusted, adjusted for age and adjusted for all the characteristics.ResultsThe prevalence of prosthetic treatment was 34.6% (95% confidence interval (CI): [34.1; 35.2]) for fixed prosthetic dentures and 13.8% (95% CI: [13.4; 14.2]) for removable prosthetic dentures. We showed a gradient between educational attainment and removable dentures; the odds ratio adjusted for all the variables (aOR) associated with no or primary education compared to post-secondary education was 2.56; 95% CI: [2.09; 3.13]. When annual household income per capita was low, subjects were less likely to report fixed dentures (aOR = 0.68; 95% CI: [0.62; 0.75]) than those with high annual household income per capita. Individuals without insurance less often reported fixed dentures than those with private insurance. Those reporting chronic disease were less likely to report fixed dentures (aOR = 0.87; 95% CI: [0.79; 0.95]) but more likely to report removable dentures (aOR = 1.29; 95% CI: [1.17; 1.43]) than those without chronic disease.ConclusionThis study reveals social, economic and medical inequalities in fixed and removable prosthetic treatment among adults in France.  相似文献   
33.
34.
35.
G. Berlin  M. Hammar  L. Tapper 《Platelets》2019,30(4):473-479
Platelets are needed to prevent or arrest bleeding and aggregate at the site of injury upon vascular damage. Platelets express receptors for estrogens which might affect the function of the platelets and their hemostatic ability. The aim was to identify possible differences in platelet function related to age, gender, and phases of the menstrual cycle by use of impedance aggregometry with Multiplate. In the first part of the study, platelet function was assessed in 60 healthy individuals (30 men and 30 women) in each of three age groups (20–25, 40–45, and 60–65 years). In the second part of the study, the platelet function was analyzed on four occasions during the menstrual cycle in women without oral contraceptives (OCs) (n = 17) and compared to 19 women on OCs and 18 men of similar age (20–40 years). For the women on OCs, aggregation was analyzed once during the tablet-free week and once late during the period with OCs. The men were sampled once. Women of younger age (<45 years) had significantly higher agonist-induced aggregation response than both men and post-menopausal women (60–65 years). The agonist-induced aggregation response did not differ between phases of the menstrual cycle or OC use. The results suggest that estradiol and/or progesterone affect spontaneous aggregation since it was found to be lowest in the mid-luteal phase. Spontaneous aggregation was significantly lower in women on OCs than in both men and women without OCs. Our findings indicate that fertile age is associated with higher aggregation response capacity of the platelets, possibly to prevent excessive bleeding during menstruation, but this response capacity is not altered during the menstrual cycle or by use of OCs.  相似文献   
36.
37.
38.
Graefe's Archive for Clinical and Experimental Ophthalmology - The published online version contains mistake as the author's first name and last name have been interchanged as "Hild...  相似文献   
39.
40.
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