全文获取类型
收费全文 | 1383599篇 |
免费 | 100513篇 |
国内免费 | 5987篇 |
专业分类
耳鼻咽喉 | 20274篇 |
儿科学 | 40918篇 |
妇产科学 | 39099篇 |
基础医学 | 191897篇 |
口腔科学 | 40626篇 |
临床医学 | 118255篇 |
内科学 | 268822篇 |
皮肤病学 | 30744篇 |
神经病学 | 108801篇 |
特种医学 | 55835篇 |
外国民族医学 | 447篇 |
外科学 | 214307篇 |
综合类 | 41047篇 |
现状与发展 | 25篇 |
一般理论 | 440篇 |
预防医学 | 96314篇 |
眼科学 | 32212篇 |
药学 | 105007篇 |
59篇 | |
中国医学 | 6265篇 |
肿瘤学 | 78705篇 |
出版年
2018年 | 13230篇 |
2016年 | 11937篇 |
2015年 | 14188篇 |
2014年 | 19452篇 |
2013年 | 28410篇 |
2012年 | 37563篇 |
2011年 | 39625篇 |
2010年 | 24305篇 |
2009年 | 23167篇 |
2008年 | 36932篇 |
2007年 | 39671篇 |
2006年 | 40031篇 |
2005年 | 38304篇 |
2004年 | 36826篇 |
2003年 | 35676篇 |
2002年 | 34821篇 |
2001年 | 64397篇 |
2000年 | 65966篇 |
1999年 | 55808篇 |
1998年 | 14883篇 |
1997年 | 13672篇 |
1996年 | 13144篇 |
1995年 | 12419篇 |
1994年 | 11612篇 |
1992年 | 42877篇 |
1991年 | 41403篇 |
1990年 | 40660篇 |
1989年 | 39646篇 |
1988年 | 37042篇 |
1987年 | 36483篇 |
1986年 | 34965篇 |
1985年 | 33168篇 |
1984年 | 24894篇 |
1983年 | 21100篇 |
1982年 | 12711篇 |
1981年 | 11617篇 |
1979年 | 23966篇 |
1978年 | 17114篇 |
1977年 | 14867篇 |
1976年 | 13414篇 |
1975年 | 15305篇 |
1974年 | 18116篇 |
1973年 | 17596篇 |
1972年 | 16834篇 |
1971年 | 15741篇 |
1970年 | 14946篇 |
1969年 | 14373篇 |
1968年 | 13481篇 |
1967年 | 12029篇 |
1966年 | 11267篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
73.
Paul J. Devlin Brian W. McCrindle James K. Kirklin Eugene H. Blackstone William M. DeCampli Christopher A. Caldarone Ali Dodge-Khatami Pirooz Eghtesady James M. Meza Peter J. Gruber Kristine J. Guleserian Bahaaladin Alsoufi Linda M. Lambert James E. OBrien Erle H. Austin Jeffrey P. Jacobs Tara Karamlou 《The Journal of thoracic and cardiovascular surgery》2019,157(2):684-695.e8
Objective
Arch obstruction after the Norwood procedure is common and contributes to mortality. We determined the prevalence, associated factors, and practice variability of arch reintervention and assessed whether arch reintervention is associated with mortality.Methods
From 2005 to 2017, 593 neonates in the Congenital Heart Surgeons' Society Critical Left Heart Obstruction cohort underwent a Norwood procedure. Median follow-up was 3.7 years. Multivariable parametric models, including a modulated renewal analysis, were performed.Results
Of the 593 neonates, 146 (25%) underwent 218 reinterventions for arch obstruction after the Norwood procedure: catheter-based (n = 168) or surgical (n = 50) at a median age of 4.3 months (quartile 1-quartile 3, 2.6-5.7). Interdigitation of the distal aortic anastomosis was protective against arch reintervention. Development of ≥ moderate tricuspid valve regurgitation and right ventricular dysfunction at any point was associated with arch reintervention. Nonsignificant variables for arch reintervention included shunt type and preoperative aortic measurements. Surgical arch reintervention was protective against arch reintervention, but transcatheter reintervention was associated with increased reintervention. Arch reintervention was not associated with increased mortality. There was wide institutional variation in incidence of arch reintervention (range, 0-40 reinterventions per 100 years patient follow-up) and in preintervention gradient (range, 0-64 mm Hg).Conclusions
Interdigitation of the distal aortic anastomosis during the Norwood procedure decreased the risk of arch reintervention. Surgical arch reintervention is more definitive than transcatheter. Arch reintervention after the Norwood procedure is not associated with increased mortality. Serial surveillance for arch obstruction, integrated with changes in right ventricular function and tricuspid valve regurgitation, is recommended after the Norwood procedure to improve outcomes. 相似文献74.
75.
76.
Michael L. Goodman Miriam S. Mutambudzi Stanley Gitari Philip H. Keiser Sarah E. Seidel 《Vulnerable children and youth studies》2016,11(4):366-378
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
77.
78.
79.
80.
Anders Elm Pedersen Esben Gjerløff Wedebye Schmidt Jesper Freddie Sørensen Carsten Faber Boye Schnack Nielsen Kim Holmstrøm Silje Haukali Omland Peter Tougaard Søren Skov Bo Bang 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2015,123(7):547-555
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