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   2439737篇
  免费   203020篇
  国内免费   4634篇
耳鼻咽喉   35110篇
儿科学   74371篇
妇产科学   64071篇
基础医学   343766篇
口腔科学   69348篇
临床医学   222376篇
内科学   482801篇
皮肤病学   49084篇
神经病学   207526篇
特种医学   98798篇
外国民族医学   886篇
外科学   371812篇
综合类   56796篇
现状与发展   1篇
一般理论   1154篇
预防医学   195265篇
眼科学   56824篇
药学   181784篇
  4篇
中国医学   4478篇
肿瘤学   131136篇
  2019年   19235篇
  2018年   26597篇
  2017年   20450篇
  2016年   22426篇
  2015年   25332篇
  2014年   36318篇
  2013年   54477篇
  2012年   74212篇
  2011年   77812篇
  2010年   45586篇
  2009年   43651篇
  2008年   73374篇
  2007年   77518篇
  2006年   78261篇
  2005年   76221篇
  2004年   73162篇
  2003年   70495篇
  2002年   69433篇
  2001年   112889篇
  2000年   116865篇
  1999年   98819篇
  1998年   28548篇
  1997年   26046篇
  1996年   25879篇
  1995年   25053篇
  1994年   23493篇
  1993年   21883篇
  1992年   79645篇
  1991年   76620篇
  1990年   73794篇
  1989年   71042篇
  1988年   66057篇
  1987年   64984篇
  1986年   61525篇
  1985年   58617篇
  1984年   44477篇
  1983年   37872篇
  1982年   23143篇
  1981年   20574篇
  1979年   41408篇
  1978年   29135篇
  1977年   24480篇
  1976年   22923篇
  1975年   24069篇
  1974年   29737篇
  1973年   28123篇
  1972年   26305篇
  1971年   24216篇
  1970年   22806篇
  1969年   21128篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
73.

Background

Resistin is an immunometabolic mediator that is elevated in several inflammatory disorders. A ligand for Toll-like receptor 4, resistin modulates the recruitment and activation of myeloid cells, notably neutrophils. Neutrophils are major drivers of cystic fibrosis (CF) lung disease, in part due to the release of human neutrophil elastase- and myeloperoxidase-rich primary granules, leading to tissue damage. Here we assessed the relationship of resistin to CF lung disease.

Methods

Resistin levels were measured in plasma and sputum from three retrospective CF cohorts spanning a wide range of disease. We also assessed the ability of neutrophils to secrete resistin upon activation in vitro. Finally, we constructed a multivariate model assessing the relationship between resistin levels and lung function.

Results

Plasma resistin levels were only marginally higher in CF than in healthy control subjects. By contrast, sputum resistin levels were very high in CF, reaching 50–100 fold higher levels than in plasma. Among CF patients, higher plasma resistin levels were associated with allergic bronchopulmonary aspergillosis, and higher sputum resistin levels were associated with CF-related diabetes. Mechanistically, in vitro release of neutrophil primary granules was concomitant with resistin secretion. Overall, sputum resistin levels were negatively correlated with CF lung function, independently of other variables (age, sex, and genotype).

Conclusions

Our data establish relationships between resistin levels in the plasma and sputum of CF patients that correlate with disease status, and identify resistin as a novel mechanistic link between neutrophilic inflammation and lung disease in CF.  相似文献   
74.
75.
ContextIt is especially important that patients are well informed when making high-stakes, preference-sensitive decisions like those on the Physician Orders for Life-Sustaining Treatment (POLST) form. However, there is currently no way to easily evaluate whether patients understand key concepts when making these important decisions.ObjectivesTo develop a POLST knowledge survey.MethodsExpert (n = 62) ratings of key POLST facts were used to select items for a POLST knowledge survey. The survey was administered to nursing facility residents (n = 97) and surrogate decision-makers (n = 112). A subset (n = 135) were re-administered the survey after a standardized advance care planning discussion to assess the scale's responsiveness to change.ResultsThe 19-item survey demonstrated adequate reliability (α = 0.72.). Residents' scores (x = 11.4, standard deviation 3.3) were significantly lower than surrogate scores (x = 14.7, standard deviation 2.5) (P < 0.001). Scores for both groups increased significantly after administration of a standardized advance care planning discussion (P < 0.001). Although being a surrogate, age, race, education, cognitive functioning, and health literacy were significantly associated with higher POLST Knowledge Survey scores in univariate analyses, only being a surrogate (P < 0.001) and being white (P = 0.028) remained significantly associated with higher scores in multivariate analyses.ConclusionThe 19-item POLST Knowledge Survey demonstrated adequate reliability and responsiveness to change. Findings suggest the survey could be used to identify knowledge deficits and provide targeted education to ensure adequate understanding of key clinical decisions when completing POLST.  相似文献   
76.
77.
78.
79.
Caring for patients with end-stage kidney disease (ESKD) in the United States is challenging, due in part to the complex epidemiology of the disease's progression as well as the ways in which care is delivered. As CKD progresses toward ESKD, the number of comorbidities increases and care involves multiple healthcare providers from multiple subspecialties. This occurs in the context of a fragmented US healthcare delivery system that is traditionally siloed by provider specialty, organization, as well as systems of payment and administration. This article describes the role of care fragmentation in the delivery of optimal ESKD care and identifies research gaps in the evidence across the continuum of care. We then consider the impact of care fragmentation on ESKD care from the patient and health system perspectives and explore opportunities for system-level interventions aimed at improving care for patients with ESKD.  相似文献   
80.
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