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   6254篇
  免费   345篇
  国内免费   58篇
耳鼻咽喉   162篇
儿科学   121篇
妇产科学   166篇
基础医学   828篇
口腔科学   134篇
临床医学   476篇
内科学   1503篇
皮肤病学   378篇
神经病学   453篇
特种医学   318篇
外科学   898篇
综合类   68篇
预防医学   362篇
眼科学   100篇
药学   358篇
中国医学   6篇
肿瘤学   326篇
  2021年   75篇
  2020年   47篇
  2019年   68篇
  2018年   95篇
  2017年   63篇
  2016年   104篇
  2015年   112篇
  2014年   150篇
  2013年   175篇
  2012年   267篇
  2011年   268篇
  2010年   163篇
  2009年   176篇
  2008年   264篇
  2007年   318篇
  2006年   256篇
  2005年   272篇
  2004年   275篇
  2003年   268篇
  2002年   221篇
  2001年   192篇
  2000年   237篇
  1999年   231篇
  1998年   88篇
  1997年   66篇
  1996年   64篇
  1995年   45篇
  1994年   46篇
  1993年   57篇
  1992年   92篇
  1991年   111篇
  1990年   110篇
  1989年   132篇
  1988年   99篇
  1987年   79篇
  1986年   80篇
  1985年   75篇
  1984年   56篇
  1983年   42篇
  1980年   37篇
  1979年   53篇
  1978年   39篇
  1977年   36篇
  1975年   45篇
  1974年   47篇
  1973年   55篇
  1972年   43篇
  1971年   46篇
  1970年   37篇
  1969年   37篇
排序方式: 共有6657条查询结果,搜索用时 6 毫秒
111.
Associations between maternal nutritional factors including energy intake, body mass index, postpartum weight change, and anemia status and maternal-infant interactions were examined in 124 mother-infant pairs from a marginally malnourished, rural Kenyan population. Anemic mothers spent less time holding and caring for their infants than nonanemic mothers. Mothers who retained their pregnancy weight gain or were able to gain weight postpartum spent more time looking at their infants than mothers who lost weight postpartum. Maternal food intake per se was not associated with patterns of infant interaction. Lower birth weight infants were held more, cared for more, and looked at face-to-face more by their mothers. Older sisters tended to be more involved in infant interactions with higher birth weight infants.  相似文献   
112.
Overcoming dendritic cell (DC) dysfunction is a prerequisite for successful active immunotherapy against breast cancer. CD40 ligand (CD40L), a key molecule in the interface between T-lymphocytes and DCs, seems to be instrumental in achieving that goal. Commenting on our data that CD40L protects circulating DCs from apoptosis induced by breast tumor products, Lenahan and Avigan highlighted the potential of CD40L for immunotherapy. We expand on that argument by pointing to additional findings that CD40L not only rescues genuine DCs but also functionally improves populations of immature antigen-presenting cells that fill the DC compartment in patients with breast cancer.  相似文献   
113.
Twice in fifteen months the popular press has published reports of the discovery of a new human organ. The claims that the mesentery and interstitium are organs come from medical practitioners, not from anatomical scientists. Although both of these anatomical entities are important in the functioning of the body, neither satisfies the requirements that an organ be composed of two or more tissues and perform a special function. Also missing in the recent claim that the interstitium, that is, connective tissues with fluid‐filled spaces, is an organ, is a statement to that effect in the original research report. Alas, it appears to be much ado about nothing. Clin. Anat. 31:648–649, 2018. © 2018 Wiley Periodicals, Inc.  相似文献   
114.
115.
In this survey, almost 30 borrowed words in anatomical Latin were found to differ from the original Greek noun in gender and/or inflection. A third of these cases were judged to be errors. The rest are long‐standing or widely‐accepted exceptions to the usual adoption rules for borrowed Greek words. Possible linguistic explanations for these exceptions are presented. Clin. Anat. 31:306–309, 2018. © 2018 Wiley Periodicals, Inc.  相似文献   
116.
This study used event-related potentials (ERPs) to investigate discourse-coherence processing. Because there are scant data on ERP indices of discourse coherence in typical adults, it is important to study a non-clinical population before examining clinical populations. Twelve adults listened to a story with sentences in a coherent versus incoherent order. Sequences of nonsense syllables served as a control. ERPs in the 200–400?ms time window, reflecting phonological and lexical processing, and in the 600–900?ms time window, reflecting later discourse processing for integration, were investigated. Results revealed a right anterior and posterior positivity that was greater for coherent than for incoherent discourse during the 600–900?ms time window. These findings point to an index of discourse coherence and further suggest that ERPs can be used as a clinical tool to study discourse-processing disorders in populations with brain damage, such as aphasia and traumatic brain injury.  相似文献   
117.
118.
119.
120.
In 1986, Congress passed the Emergency Planning and Community Right‐to‐Know Act (EPCRA) in response to the tragic death of thousands of people in Bhopal, India, following the accidental release of the toxic gas methyl isocyanate (MIC) from a Union Carbide facility. As a component of EPCRA, certain manufacturers are required to report annually the total mass (pounds per year, 1b/yr) of toxic chemicals released into the environment (air, water, land, or underground injection), treated on‐site, or shipped off‐site for further waste treatment. This information is compiled by the U.S. Environmental Protection Agency (EPA) into a publicly accessible database known as the Toxic Release Inventory (TRI). The TRI database is designed to encourage pollution prevention and waste reduction by increasing public access to and knowledge of environmental chemical releases. EPCRA has been generally considered by industry, government, and community representatives as one of the most successful environmental laws in U.S. history. Over the past few years, EPA has initiated a three‐phased expansion to EPCRA reporting requirements that will enhance the overall usefulness of the TRI database. The focus of this article is to discuss these changes and highlight several current uses of the TRI database in environmental health research.  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