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   2301篇
  免费   740篇
  国内免费   21篇
耳鼻咽喉   15篇
儿科学   131篇
妇产科学   12篇
基础医学   31篇
口腔科学   18篇
临床医学   812篇
内科学   962篇
皮肤病学   53篇
神经病学   134篇
特种医学   16篇
外科学   187篇
综合类   4篇
一般理论   3篇
预防医学   376篇
眼科学   11篇
药学   91篇
肿瘤学   206篇
  2024年   20篇
  2023年   149篇
  2022年   87篇
  2021年   96篇
  2020年   195篇
  2019年   52篇
  2018年   197篇
  2017年   198篇
  2016年   201篇
  2015年   192篇
  2014年   218篇
  2013年   226篇
  2012年   65篇
  2011年   51篇
  2010年   155篇
  2009年   246篇
  2008年   66篇
  2007年   39篇
  2006年   50篇
  2005年   56篇
  2004年   33篇
  2003年   31篇
  2002年   20篇
  2001年   35篇
  2000年   37篇
  1999年   46篇
  1998年   46篇
  1997年   44篇
  1996年   41篇
  1995年   37篇
  1994年   19篇
  1993年   20篇
  1992年   12篇
  1991年   9篇
  1990年   8篇
  1989年   6篇
  1988年   4篇
  1987年   9篇
  1986年   4篇
  1985年   5篇
  1984年   5篇
  1983年   5篇
  1982年   2篇
  1981年   2篇
  1958年   2篇
  1956年   4篇
  1954年   4篇
  1950年   1篇
  1949年   3篇
  1948年   3篇
排序方式: 共有3062条查询结果,搜索用时 734 毫秒
1.
2.
3.
4.
5.
6.
Objective To examine the relationship of cancer prevention-related nutrition knowledge, beliefs, and attitudes to cancer prevention dietary behavior.Subjects/setting Noninstitutionalized US adults aged 18 years and older.Methods Data collected in the 1992 National Health Interview Survey Cancer Epidemiology Supplement were analyzed. The supplement included questions to ascertain knowledge, beliefs, and attitudes and a food frequency questionnaire to ascertain nutrient intake.Statistics Multivariate linear regression modeling was conducted to assess the hypothesized relationships.Results After adjustment for relevant covariates (age, sex, education, total energy, perceived barriers to eating a more healthful diet), knowledge and belief constructs were predictive of dietary behavior. Specifically, fat, fiber, and fruit and vegetable intakes more closely approximated dietary recommendations for persons with more cancer-prevention knowledge. The strength of the associations between these constructs and dietary behavior varied in some cases according to level of education and perceived barriers to eating a healthful diet. Of the perceived barriers to eating a healthful diet, perceived ease of eating a healthful diet was most strongly and consistently predictive of intake.Conclusions Research findings challenge dietetics practitioners to design diet- and health-promotion programs and activities that not only educate the public about the importance of diet to health, but also address barriers to dietary change.  相似文献   
7.
8.
9.
It is unclear whether single and combined pharmacologic inhibition of the renin-angiotensin-aldosterone system have similar effects on endothelial function and blood pressure (BP). The authors evaluated 63 hypertensive patients divided into 4 groups (hydrochlorothiazide 25 mg/d; irbesartan [IRBE] 150 mg/d; quinapril [QUIN] 20 mg/d; or IRBE 150 mg/d + QUIN 20 mg/d) and 25 healthy normotensive subjects (normal) followed for 12 weeks. Endothelium-dependent dysfunction measured as flow-mediated dilation at Weeks 0 and 12 were: normal, 11.5%±2.4% vs 13.5%±2.0%; hydrochlorothiazide, 7.3%±2.0% vs 12.8%±3.1%; QUIN, 7.2%±2.8% vs 13.2%±2.1%; IRBE, 7.1%±2.8% vs 13.0%±2.9%; and IRBE + QUIN, 7.5%±1.9% vs 12.8%±3.0%. Nitroglycerin-mediated responses were: normal, 26.0%±1.9% vs 24.0%±2.5%; hydrochlorothiazide, 17.0%±2.2% vs 18.3%±2.6%; QUIN, 17.8%±3.2% vs 23.4%±3.0%; IRBE, 16.8%±3.6% vs 24.7%±2.0%; and IRBE + QUIN, 17.3%±3.0% vs 25.1%±2.5%. Antihypertensive therapy restored BP to normal and improved the endothelium-dependent and -independent dysfunction after renin-angiotensin-aldosterone system blockade. In a further finding, the combined effect of angiotensin-converting enzyme inhibition and angiotensin II type 1 receptor blockade was not superior to the action of either of these treatments separately.  相似文献   
10.
A new regimen for postoperative analgesia after thoracic surgery is proposed. Eight children received an interpleural infusion using bupivacaine 0.1% in a regimen from 0.5 ml·kg?1·h?1 up to 1 ml·kg?1·h?1, for 48 h according to the pain scores. The plasma levels after 24 h and 48 h were measured as well as the pleural level and in two patients the free fraction of plasma bupivacaine and the plasma PPX (a metabolite of bupivacaine) and one patient the orosomucoid (main plasma protein involved in bupivacaine protein binding) were also measured pre and postoperatively. The results shows the safety of such a regimen, for two days of postoperative analgesia.  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