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   1701281篇
  免费   126767篇
  国内免费   3834篇
耳鼻咽喉   21790篇
儿科学   55783篇
妇产科学   46246篇
基础医学   242183篇
口腔科学   49087篇
临床医学   151864篇
内科学   335561篇
皮肤病学   38870篇
神经病学   131737篇
特种医学   64390篇
外国民族医学   242篇
外科学   258763篇
综合类   38983篇
现状与发展   4篇
一般理论   531篇
预防医学   124515篇
眼科学   40336篇
药学   124254篇
  7篇
中国医学   4487篇
肿瘤学   102249篇
  2021年   12945篇
  2019年   13644篇
  2018年   20123篇
  2017年   15352篇
  2016年   16793篇
  2015年   19107篇
  2014年   26460篇
  2013年   38237篇
  2012年   53157篇
  2011年   55912篇
  2010年   33043篇
  2009年   30939篇
  2008年   51926篇
  2007年   55230篇
  2006年   55688篇
  2005年   52977篇
  2004年   51151篇
  2003年   48521篇
  2002年   46756篇
  2001年   92027篇
  2000年   93834篇
  1999年   77236篇
  1998年   19838篇
  1997年   17367篇
  1996年   17466篇
  1995年   16811篇
  1994年   15365篇
  1993年   14124篇
  1992年   57522篇
  1991年   55402篇
  1990年   53113篇
  1989年   50897篇
  1988年   46241篇
  1987年   45062篇
  1986年   42353篇
  1985年   40124篇
  1984年   29455篇
  1983年   24982篇
  1982年   13920篇
  1979年   25608篇
  1978年   17644篇
  1977年   14964篇
  1976年   13903篇
  1975年   14594篇
  1974年   17674篇
  1973年   16986篇
  1972年   15709篇
  1971年   14482篇
  1970年   13454篇
  1969年   12559篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
There are an estimated 56 million orphans and vulnerable children across sub-Saharan Africa. Communities typically care for orphan children through informal caring arrangements – either within or outside of kinship networks. Within Kenya, an estimated 250,000 children live on the streets. There is less research related to fostering attitudes of this special population than orphans and vulnerable children generally. Important research over the past decade has illuminated multiple ways in which children are made more vulnerable because of HIV, including parental death and street-migration from HIV-affected households. As HIV transitions from a terminal illness to a chronic, manageable one, research is also required to establish how parents living with HIV can be an asset to children. In this study, we assess whether mothers living with HIV were very willing to foster biologically-related children, and street-involved children, how these fostering attitudes differed from mothers not living with HIV, and whether differences in fostering attitudes by reported HIV status were mediated by social support, family functioning and general self-rated health. Approximately 40% of mothers living with HIV were very willing to provide long-term foster care to biologically-related or street-involved children. This was less than the percentage of mothers not living with HIV, who were very willing to foster biologically-related children (61%) or street-involved children (58%). Significant portions of these differences were explained by social support, family functioning and general self-rated health. Multi-sectoral approaches are suggested by these findings in order to improve the child-fostering capacity of mothers living with HIV. Improving social support, family functioning and general self-rated health among HIV-infected mothers may not only provide protective benefits for the mothers and their children, but also expand the community’s capacity to care for orphan and vulnerable children.  相似文献   
102.
103.
104.
105.
106.
Demodex mites are microscopic arachnids found in the normal skin of many mammals. In humans, it is well established that Demodex mite density is higher in patients with the skin condition rosacea, and treatment with acaricidal agents is effective in resolving symptoms. However, pathophysiology of rosacea is complex and multifactorial. In dogs, demodicosis is a significant veterinary issue, particularly the generalized form of the disease which can be fatal if untreated. In each species, clinical and molecular studies have shown that the host’s immunological interactions with Demodex mites are an important, but not fully understood, aspect of how Demodex can live in the skin either as a harmless commensal organism or as a pathogenic agent. This review outlines the role of Demodex mites in humans and dogs, considering morphology, prevalence, symptoms, diagnosis, histology treatment and pathogenesis.  相似文献   
107.
108.
109.
110.
TL1A is a TNF‐like cytokine which has been shown to co‐stimulate TH1 and TH17 responses during chronic inflammation. The expression of this novel cytokine has been investigated in inflammatory disorders like rheumatoid arthritis and inflammatory bowel disease, but little is known about expression and induction in psoriasis. Indeed, the pathogenesis in psoriasis is still not fully understood and it is speculated that cytokines other than TNF‐α are important in subsets of patients. Also, for patients with severe disease that are treated with systemic anti‐TNF‐α blockade, novel candidates to be used as disease and response biomarkers are of high interest. Here, we demonstrate TL1A expression in biopsies from psoriatic lesions. Also, we investigated spontaneous and induced TL1A secretion from PBMCs and blood levels from a cohort of psoriasis patients. Here, increased spontaneous secretion from PBMCs was observed as compared to healthy controls and a small subset of patients had highly elevated TL1A in the blood. Interestingly, activation of PBMCs with various cytokines showed a decreased sensitivity for TL1A activation in psoriasis patients compared to healthy controls.TL1A levels in blood and biopsies could not be correlated with disease activity with this patient cohort. Thus, additional large‐scale studies are warranted to investigate TL1A as a biomarker.  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