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   304083篇
  免费   16883篇
  国内免费   794篇
耳鼻咽喉   4158篇
儿科学   9681篇
妇产科学   6715篇
基础医学   41324篇
口腔科学   11194篇
临床医学   21686篇
内科学   70356篇
皮肤病学   8519篇
神经病学   25703篇
特种医学   8466篇
外国民族医学   27篇
外科学   37150篇
综合类   2128篇
现状与发展   1篇
一般理论   129篇
预防医学   31443篇
眼科学   6034篇
药学   19435篇
  1篇
中国医学   1289篇
肿瘤学   16321篇
  2023年   1878篇
  2022年   3149篇
  2021年   7045篇
  2020年   4267篇
  2019年   6935篇
  2018年   10015篇
  2017年   6783篇
  2016年   6413篇
  2015年   7227篇
  2014年   9490篇
  2013年   12733篇
  2012年   20392篇
  2011年   21406篇
  2010年   10930篇
  2009年   9077篇
  2008年   16614篇
  2007年   17569篇
  2006年   16410篇
  2005年   16494篇
  2004年   15155篇
  2003年   13953篇
  2002年   11655篇
  2001年   8620篇
  2000年   9221篇
  1999年   7478篇
  1998年   2157篇
  1997年   1732篇
  1996年   1667篇
  1995年   1422篇
  1994年   1316篇
  1993年   1204篇
  1992年   3878篇
  1991年   3571篇
  1990年   3249篇
  1989年   3074篇
  1988年   2746篇
  1987年   2561篇
  1986年   2438篇
  1985年   2238篇
  1984年   1653篇
  1983年   1299篇
  1982年   730篇
  1979年   1259篇
  1978年   819篇
  1975年   804篇
  1974年   861篇
  1973年   897篇
  1972年   740篇
  1970年   743篇
  1969年   751篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
91.
92.
Melatonin, the main hormone produced by the pineal gland, is secreted in a circadian manner (24‐hr period), and its oscillation influences several circadian biological rhythms, such as the regulation of clock genes expression (chronobiotic effect) and the modulation of several endocrine functions in peripheral tissues. Assuming that the circadian synchronization of clock genes can play a role in the regulation of energy metabolism and it is influenced by melatonin, our study was designed to assess possible alterations as a consequence of melatonin absence on the circadian expression of clock genes in the epididymal adipose tissue of male Wistar rats and the possible metabolic repercussions to this tissue. Our data show that pinealectomy indeed has impacts on molecular events: it abolishes the daily pattern of the expression of Clock, Per2, and Cry1 clock genes and Pparγ expression, significantly increases the amplitude of daily expression of Rev‐erbα, and affects the pattern of and impairs adipokine production, leading to a decrease in leptin levels. However, regarding some metabolic aspects of adipocyte functions, such as its ability to synthesize triacylglycerols from glucose along 24 hr, was not compromised by pinealectomy, although the daily profile of the lipogenic enzymes expression (ATP‐citrate lyase, malic enzyme, fatty acid synthase, and glucose‐6‐phosphate dehydrogenase) was abolished in pinealectomized animals.  相似文献   
93.
The jobs of Latino manual laborers place their mental and physical health at risk. This study evaluates the associations among musculoskeletal pain, mental health, and work organization in Latino manual laborers. Farmworkers and nonfarmworkers (n = 189) in North Carolina were interviewed for self-reported musculoskeletal pain, depressive symptoms, stress, work safety climate, and precarious job status. More nonfarmworkers than farmworkers had neck and shoulder pain, but they did not differ in other areas of musculoskeletal pain. Depressive symptoms had a significant association with neck and shoulder pain (p < .05). Precariousness had a significant association with back pain (p < .05). Farmworker participants had H-2A visas and were afforded some protection compared to nonfarmworker manual workers. Research is needed to improve policy that relieves pain and improves mental health for all Latino manual workers.  相似文献   
94.
95.
96.
97.
Gray platelet syndrome (GPS) is a rare (<1/1 000 000) and inherited platelet function disorder characterized by macrothrombocytopenia, α-granule deficiency, and hemorrhages. Bleeding intensity does not correlate with platelet count nor with functional test results. We hereby describe the perioperative bleeding prevention and management of a patient with GPS requiring multiple redo cardiac surgeries.  相似文献   
98.
99.
100.
ObjectiveTo present, the process of development and evaluation of an educational software on the Child Health Handbook proposed for the continuing education of primary care nurses and physicians.MethodsQuantitative study of methodological development. For software development, the following steps were followed: definition of objectives; determination of the target audience; choice of pedagogical and theoretical reference for content; content selection and structuring; software development and evaluation by experts (five nurses and four physicians). All responded to an instrument that included four domains: pedagogical; content; functionality; system presentation and usability. The evaluation criteria were arranged on a Likert-type scale. The percentage of agreement and Content Validity Index were used for the quantitative analysis of the degree of agreement, considering a Content Validity Index cutoff point equal to 0.80.ResultsThe overall agreement index, calculated by the arithmetic mean of the Contents Validity Index of the evaluated domains, was 0.96, with scores ranging from 0.90 to 1.00. The average percentage of agreement of the experts per domain was 92.86%, with lower agreement in the content (80.95%), presentation, and usability (90.48%) domains. 100% of percentage of agreement was observed in the pedagogical and functionality domains among the evaluated specialists.ConclusionThe percentage of agreement, Content Validity Index and overall agreement index of the Child Health Handbook educational software in the context of primary care disclosed the software adequacy as an educational resource for continuing education of primary care nurses and physicians. Considering the assessed dimensions, it can also be used by other health professionals and undergraduate students.  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