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   520702篇
  免费   34388篇
  国内免费   639篇
耳鼻咽喉   6954篇
儿科学   16957篇
妇产科学   13607篇
基础医学   85835篇
口腔科学   14732篇
临床医学   44745篇
内科学   95427篇
皮肤病学   12244篇
神经病学   37112篇
特种医学   18802篇
外国民族医学   63篇
外科学   78482篇
综合类   8487篇
一般理论   118篇
预防医学   39170篇
眼科学   12220篇
药学   40976篇
中国医学   1015篇
肿瘤学   28783篇
  2018年   5071篇
  2016年   4201篇
  2015年   4638篇
  2014年   6229篇
  2013年   9742篇
  2012年   13231篇
  2011年   14642篇
  2010年   8523篇
  2009年   7945篇
  2008年   13992篇
  2007年   15078篇
  2006年   15292篇
  2005年   14700篇
  2004年   14354篇
  2003年   13679篇
  2002年   13576篇
  2001年   24363篇
  2000年   25348篇
  1999年   20826篇
  1998年   5514篇
  1997年   4782篇
  1996年   5109篇
  1995年   4684篇
  1994年   4369篇
  1992年   15902篇
  1991年   16484篇
  1990年   16563篇
  1989年   15947篇
  1988年   14712篇
  1987年   14552篇
  1986年   13737篇
  1985年   13092篇
  1984年   9698篇
  1983年   8321篇
  1982年   4583篇
  1981年   4254篇
  1979年   9472篇
  1978年   6894篇
  1977年   5808篇
  1976年   5625篇
  1975年   6422篇
  1974年   7665篇
  1973年   7165篇
  1972年   6982篇
  1971年   6710篇
  1970年   6204篇
  1969年   5920篇
  1968年   5585篇
  1967年   5036篇
  1966年   4474篇
排序方式: 共有10000条查询结果,搜索用时 12 毫秒
31.
32.
33.
34.
Thyroid diseases are common, and use of levothyroxine is increasing worldwide. We investigated the influence of gender, race and socioeconomic status on the diagnosis and treatment of thyroid disorders using data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil), a multicenter cohort study of civil servants (35-74 years of age) from six Brazilian cities. Diagnosis of thyroid dysfunction was by thyrotropin (TSH), and free thyroxine (FT4) if TSH was altered, and the use of specific medications. Multivariate logistic regression models were constructed using overt hyperthyroidism/hypothyroidism and levothyroxine use as dependent variables and sociodemographic characteristics as independent variables. The frequencies of overt hyper- and hypothyroidism were 0.7 and 7.4%, respectively. Using whites as the reference ethnicity, brown, and black race were protective for overt hypothyroidism (OR=0.76, 95%CI=0.64-0.89, and OR=0.53, 95%CI=0.43-0.67, respectively, and black race was associated with overt hyperthyroidism (OR=1.82, 95%CI=1.06-3.11). Frequency of hypothyroidism treatment was higher in women, browns, highly educated participants and those with high net family incomes. After multivariate adjustment, levothyroxine use was associated with female gender (OR=6.06, 95%CI=3.19-11.49) and high net family income (OR=3.23, 95%CI=1.02-10.23). Frequency of hyperthyroidism treatment was higher in older than in younger individuals. Sociodemographic factors strongly influenced the diagnosis and treatment of thyroid disorders, including the use of levothyroxine.  相似文献   
35.
36.
37.
38.
39.
At this study a multi-criteria model was developed to examine the available procedures, techniques and methods of handling infectious waste in the large healthcare unit of University Regional General Hospital of Patras, Western Greece. Particularly, this study examined the: a) current legislation and Directives issued for medical waste management at Greece and among the other EU-members, b) contribution of healthcare wastes (HCW) generation rate on social and economic parameters in selected European countries, c) available procedures, techniques, and methods upon the disposal of infectious wastes at the healthcare studied, and, d) propositions for integrated management of such hazardous wastes. Specifically, the Analytic Hierarchy Process (AHP) methodology was applied under pair wise comparison matrices in two stages: 1) the scale factors and the indicators, and 2) the criteria and their sub–criteria. The assessment of these pair wise matrices included the indicators and the sub–criteria. Subsequently, two pair wise comparison matrices, upon a) the “Fulfillment of environmental objectives” indicator and b) the “Energy consumption” sub criterion, were denoted. The AHP methodology yielded good results; however there is still space of improving the environmental performance. The normalized relative weights obtained for the criteria and sub criteria motivated specific actions that have to be handled. Particularly, the results indicated a very good value in environmental management criteria due the values obtained for the commitment towards the environmental policy standards and the waste management procedures. However, further improvements on staff awareness (such as development programs to enhance sensitivity) and more green purchasing suppliers, should be further addressed.  相似文献   
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