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   1974篇
  免费   158篇
  国内免费   7篇
耳鼻咽喉   20篇
儿科学   47篇
妇产科学   56篇
基础医学   257篇
口腔科学   40篇
临床医学   188篇
内科学   392篇
皮肤病学   164篇
神经病学   204篇
特种医学   53篇
外科学   237篇
综合类   17篇
一般理论   4篇
预防医学   168篇
眼科学   24篇
药学   173篇
中国医学   2篇
肿瘤学   93篇
  2024年   3篇
  2023年   56篇
  2022年   33篇
  2021年   115篇
  2020年   95篇
  2019年   80篇
  2018年   84篇
  2017年   62篇
  2016年   60篇
  2015年   63篇
  2014年   91篇
  2013年   133篇
  2012年   137篇
  2011年   172篇
  2010年   79篇
  2009年   93篇
  2008年   126篇
  2007年   115篇
  2006年   105篇
  2005年   96篇
  2004年   68篇
  2003年   61篇
  2002年   61篇
  2001年   23篇
  2000年   12篇
  1999年   8篇
  1998年   6篇
  1997年   8篇
  1996年   6篇
  1995年   5篇
  1994年   2篇
  1993年   6篇
  1992年   11篇
  1991年   4篇
  1990年   3篇
  1989年   6篇
  1988年   3篇
  1987年   2篇
  1986年   2篇
  1985年   3篇
  1983年   3篇
  1982年   6篇
  1981年   4篇
  1980年   3篇
  1979年   2篇
  1978年   6篇
  1975年   3篇
  1971年   2篇
  1970年   2篇
  1963年   2篇
排序方式: 共有2139条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
Alopecia areata (AA) is an autoimmune form of nonscarring hair loss. The aim of the study was to assess the serum concentration of interferon gamma (IFN‐γ) and CD8 cell expression in lesional skin biopsies in correlation with the disease severity, activity, duration, and trichoscopic findings in patients with AA. The study included 30 patients with AA and 15 age‐ and sex‐matched healthy controls. Trichoscopy was performed and photographs were captured for the alopecic areas, and the enzyme‐linked immunosorbent assay technique was used for serum level of IFN‐γ assessment and immunohistochemistry for CD8 cells. The results obtained indicate that IFN‐γ serum level in patients was significantly higher than that of control subjects, and significantly correlated with the activity status and the duration of the disease. CD8+ T cells infiltrate intensity significantly correlated with severity. Yellow dots (YDs), vellus hair, black dot, and exclamation marks were the most common trichoscopic findings. The presence of black dots significantly correlated to the disease activity, duration, serum IFN‐γ, and CD8+ infiltrate intensity. The presence of YDs significantly correlated with the mean serum IFN‐γ level. Exclamation marks significantly correlated with the disease activity and the degree of CD8+ infiltrate. In conclusion, trichoscopy could be a reliable indicator of the IFN‐γ serum level and CD8+ T cell infiltrate intensity in AA patient.  相似文献   
95.
96.
Purpose

We aimed to understand how much of the gender difference in mental health service use could be due to the joint mediation of employment, behavioural and material factors, social support and mental health need.

Methods

We used data from employed individuals aged 18–65 years who participated in the 2015–2017 waves of the Household, Income and Labour Dynamics in Australia survey. The exposure (male, female) and confounders were measured in 2015, mediators in 2016 and the outcome—whether a person had seen a mental health professional in the previous year—was measured in 2017. We estimated natural mediation effects using weighted counterfactual predictions from a logistic regression model.

Results

Men were less likely to see a mental health care provider than women. The total causal effect on the risk difference scale was  − 0.045 (95% CI  − 0.056,  − 0,034). The counterfactual of men taking the mediator values of women explained 28% (95% CI 1.7%, 54%) of the total effect, with the natural direct effect estimated to represent an absolute risk difference of  − 0.033 (95% CI  − 0.048,  − 0.018) and the natural indirect effect  − 0.012 (95% CI  − 0.022,  − 0.0027).

Conclusion

Gendered differences in the use of mental health services could be reduced by addressing inequalities in health, employment, material and behavioural factors, and social support.

  相似文献   
97.
98.
In respiratory health research, interest often lies in estimating the effect of an exposure on a health outcome. If randomization of the exposure of interest is not possible, estimating its effect is typically complicated by confounding bias. This can often be dealt with by controlling for the variables causing the confounding, if measured, in the statistical analysis. Common statistical methods used to achieve this include multivariable regression models adjusting for selected confounding variables or stratification on those variables. Therefore, a key question is which measured variables need to be controlled for in order to remove confounding. An approach to confounder‐selection based on the use of causal diagrams (often called directed acyclic graphs) is discussed. A causal diagram is a visual representation of the causal relationships believed to exist between the variables of interest, including the exposure, outcome and potential confounding variables. After creating a causal diagram for the research question, an intuitive and easy‐to‐use set of rules can be applied, based on a foundation of rigorous mathematics, to decide which measured variables must be controlled for in the statistical analysis in order to remove confounding, to the extent that is possible using the available data. This approach is illustrated by constructing a causal diagram for the research question: ‘Does personal smoking affect the risk of subsequent asthma?’. Using data taken from the Tasmanian Longitudinal Health Study, the statistical analysis suggested by the causal diagram approach was performed.  相似文献   
99.
Several studies have identified inadequacies in the care and treatment received by older patients with cancer, as opposed to their younger counterparts. These include over or under diagnosis, ineffective symptom management and lower survival rates in older people with cancer. Despite these inadequacies, there is lack of evidence of older peoples' perspectives regarding their cancer diagnosis and treatment. This on going 2-site hospital based study focuses on older people's perceptions of information and decision-making in relation to treatment for cancer by using a semi-structured interview schedule. Results of the pilot study with 6 patients are presented and discussed in the light of research and clinical implications.  相似文献   
100.
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