全文获取类型
收费全文 | 1971139篇 |
免费 | 150147篇 |
国内免费 | 3545篇 |
专业分类
耳鼻咽喉 | 29005篇 |
儿科学 | 62524篇 |
妇产科学 | 58136篇 |
基础医学 | 286773篇 |
口腔科学 | 56570篇 |
临床医学 | 170127篇 |
内科学 | 380745篇 |
皮肤病学 | 40421篇 |
神经病学 | 156113篇 |
特种医学 | 77614篇 |
外国民族医学 | 524篇 |
外科学 | 306540篇 |
综合类 | 47120篇 |
现状与发展 | 3篇 |
一般理论 | 539篇 |
预防医学 | 148738篇 |
眼科学 | 46258篇 |
药学 | 149857篇 |
1篇 | |
中国医学 | 3769篇 |
肿瘤学 | 103454篇 |
出版年
2018年 | 17884篇 |
2015年 | 17960篇 |
2014年 | 25150篇 |
2013年 | 38462篇 |
2012年 | 52464篇 |
2011年 | 55846篇 |
2010年 | 32795篇 |
2009年 | 30915篇 |
2008年 | 53681篇 |
2007年 | 58351篇 |
2006年 | 58607篇 |
2005年 | 57793篇 |
2004年 | 55953篇 |
2003年 | 54153篇 |
2002年 | 52864篇 |
2001年 | 85015篇 |
2000年 | 87248篇 |
1999年 | 74214篇 |
1998年 | 21742篇 |
1997年 | 19694篇 |
1996年 | 19748篇 |
1995年 | 18673篇 |
1994年 | 17786篇 |
1993年 | 16513篇 |
1992年 | 61358篇 |
1991年 | 60425篇 |
1990年 | 59472篇 |
1989年 | 57738篇 |
1988年 | 53883篇 |
1987年 | 52986篇 |
1986年 | 50593篇 |
1985年 | 48550篇 |
1984年 | 36886篇 |
1983年 | 31919篇 |
1982年 | 19501篇 |
1981年 | 17573篇 |
1980年 | 16355篇 |
1979年 | 35979篇 |
1978年 | 25604篇 |
1977年 | 21828篇 |
1976年 | 20468篇 |
1975年 | 22316篇 |
1974年 | 26931篇 |
1973年 | 26024篇 |
1972年 | 24711篇 |
1971年 | 22920篇 |
1970年 | 21607篇 |
1969年 | 20878篇 |
1968年 | 19351篇 |
1967年 | 17354篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
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92.
93.
94.
95.
96.
Michael E Egger Joanna M Ohlendorf Charles R Scoggins Kelly M McMasters Robert C G Martin II 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2015,17(9):839-845
BackgroundThe aim of this paper is to assess the current state of quality and outcomes measures being reported for hepatic resections in the recent literature.MethodsMedline and PubMed databases were searched for English language articles published between 1 January 2002 and 30 April 2013. Two examiners reviewed each article and relevant citations for appropriateness of inclusion, which excluded papers of liver donor hepatic resections, repeat hepatectomies or meta-analyses. Data were extracted and summarized by two examiners for analysis.ResultsFifty-five studies were identified with suitable reporting to assess peri-operative mortality in hepatic resections. In only 35% (19/55) of the studies was the follow-up time explicitly stated, and in 47% (26/55) of studies peri-operative mortality was limited to in-hospital or 30 days. The time period in which complications were captured was not explicitly stated in 19 out of 28 studies. The remaining studies only captured complications within 30 days of the index operation (8/28). There was a paucity of quality literature addressing truly patient-centred outcomes.ConclusionQuality outcomes after a hepatic resection are inconsistently reported in the literature. Quality outcome studies for a hepatectomy should report mortality and morbidity at a minimum of 90 days after surgery. 相似文献
97.
98.
99.
100.
Enrique Luengo Izaskun Buendia Cristina Fernndez‐Mendívil Paula Trigo‐Alonso Pilar Negredo Patrycja Michalska Borja Hernndez‐García Cristina Snchez‐Ramos Juan A. Bernal Tsuneya Ikezu Rafael Len Manuela G. Lpez 《Journal of pineal research》2019,67(1)
Alterations in autophagy are increasingly being recognized in the pathogenesis of proteinopathies like Alzheimer's disease (AD). This study was conducted to evaluate whether melatonin treatment could provide beneficial effects in an Alzheimer model related to tauopathy by improving the autophagic flux and, thereby, prevent cognitive decline. The injection of AAV‐hTauP301L viral vectors and treatment/injection with okadaic acid were used to achieve mouse and human ex vivo, and in vivo tau‐related models. Melatonin (10 μmol/L) impeded oxidative stress, tau hyperphosphorylation, and cell death by restoring autophagy flux in the ex vivo models. In the in vivo studies, intracerebroventricular injection of AAV‐hTauP301L increased oxidative stress, neuroinflammation, and tau hyperphosphorylation in the hippocampus 7 days after the injection, without inducing cognitive impairment; however, when animals were maintained for 28 days, cognitive decline was apparent. Interestingly, late melatonin treatment (10 mg/kg), starting once the alterations mentioned above were established (from day 7 to day 28), reduced oxidative stress, neuroinflammation, tau hyperphosphorylation, and caspase‐3 activation; these observations correlated with restoration of the autophagy flux and memory improvement. This study highlights the importance of autophagic dysregulation in tauopathy and how administration of pharmacological doses of melatonin, once tauopathy is initiated, can restore the autophagy flux, reduce proteinopathy, and prevent cognitive decline. We therefore propose exogenous melatonin supplementation or the development of melatonin derivatives to improve autophagy flux for the treatment of proteinopathies like AD. 相似文献