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   35166篇
  免费   6345篇
  国内免费   108篇
耳鼻咽喉   240篇
儿科学   1021篇
妇产科学   2110篇
基础医学   2391篇
口腔科学   414篇
临床医学   17368篇
内科学   5152篇
皮肤病学   328篇
神经病学   2410篇
特种医学   461篇
外科学   2598篇
综合类   249篇
一般理论   21篇
预防医学   3735篇
眼科学   168篇
药学   1183篇
中国医学   31篇
肿瘤学   1739篇
  2024年   105篇
  2023年   966篇
  2022年   492篇
  2021年   983篇
  2020年   1091篇
  2019年   912篇
  2018年   1793篇
  2017年   1825篇
  2016年   1931篇
  2015年   2060篇
  2014年   2295篇
  2013年   2712篇
  2012年   1910篇
  2011年   2076篇
  2010年   1809篇
  2009年   1928篇
  2008年   1646篇
  2007年   1477篇
  2006年   1378篇
  2005年   1240篇
  2004年   1072篇
  2003年   868篇
  2002年   746篇
  2001年   623篇
  2000年   396篇
  1999年   558篇
  1998年   655篇
  1997年   762篇
  1996年   693篇
  1995年   612篇
  1994年   457篇
  1993年   376篇
  1992年   313篇
  1991年   295篇
  1990年   290篇
  1989年   235篇
  1988年   179篇
  1987年   175篇
  1986年   165篇
  1985年   186篇
  1984年   129篇
  1983年   122篇
  1982年   97篇
  1981年   101篇
  1980年   69篇
  1979年   101篇
  1978年   76篇
  1977年   86篇
  1976年   82篇
  1972年   101篇
排序方式: 共有10000条查询结果,搜索用时 156 毫秒
21.
The midwifery art has emphasised the uniqueness of human beings throughout its Nordic history. The educated Nordic midwife has in the last decade celebrated several hundred years of memories. This article studies how the key ideas of the midwifery art and patterns of ideas become evident in the zeitgeist from the beginning of the 19th century to the millennium in the Nordic countries. The legacy and pattern of ideas of the art of midwifery are interpreted in relation to the texts of the selected historical sources and based on Ricoeur's phenomenological-hermeneutic approach to the text and further to the dedication of understanding and interpretation. The historical sources refer to unprinted primary sources from historical archives and printed secondary and tertiary sources. The patterns of ideas include a tripartite whole: the true cultivation of the head, the philosophy and aesthetics of the hand, the strength of the heart and the drive of calling. These ideas open for unique visions and attest to the evident in modern midwives. Today's midwives have academic training with examinations, and the education is based on scientific evidence. The midwife profession is authorised by the state and supervised by the authorities.  相似文献   
22.
23.
24.
25.
26.
27.
Introduction: Current research suggests that pediatric stroke is associated with a reduction in intellectual functioning. However, less is known about academic achievement and the contribution of specific executive functions to math and literacy in this population. The current study investigates behavioral ratings of executive functioning and their relationship to math and spelling performance in children with a history of unilateral arterial ischemic stroke.

Method: Thirty-two pediatric patients with stroke (Mage = 9.5 ± 2.7 years) and 32 demographically equivalent, healthy controls were tested on standardized measures of arithmetic, spelling, and intelligence. Executive functioning data were collected via standardized parent questionnaire.

Results: Relative to controls, stroke participants demonstrated significantly poorer functioning in math, spelling, metacognition, and behavioral-regulation. Pencil and paper arithmetic was particularly challenging for the stroke group, with 40% of patients reaching levels of clinical impairment. Hierarchical regression in stroke participants further revealed that metacognition was a robust predictor of academic deficits. Stroke occurring in later childhood and affecting cortical and subcortical brain regions also presented as potential clinical risk factors.

Conclusions: Children with stroke were especially vulnerable to math achievement deficits. Metacognition made a substantial contribution to academic achievement abilities among stroke patients, and results underscore the importance of early metacognitive skills in the completion of schoolwork. Results also emphasize that pediatric stroke patients are a heterogeneous group with regard to functioning and that there is value in examining standard score distributions of clinical participant samples.  相似文献   

28.
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   
29.
30.
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