全文获取类型
| 收费全文 | 898830篇 |
| 免费 | 75514篇 |
| 国内免费 | 1936篇 |
专业分类
| 耳鼻咽喉 | 13187篇 |
| 儿科学 | 25601篇 |
| 妇产科学 | 26022篇 |
| 基础医学 | 129680篇 |
| 口腔科学 | 26347篇 |
| 临床医学 | 80310篇 |
| 内科学 | 171376篇 |
| 皮肤病学 | 17408篇 |
| 神经病学 | 73600篇 |
| 特种医学 | 36635篇 |
| 外国民族医学 | 227篇 |
| 外科学 | 140900篇 |
| 综合类 | 25446篇 |
| 现状与发展 | 2篇 |
| 一般理论 | 304篇 |
| 预防医学 | 71259篇 |
| 眼科学 | 21510篇 |
| 药学 | 67502篇 |
| 中国医学 | 1614篇 |
| 肿瘤学 | 47350篇 |
出版年
| 2018年 | 7978篇 |
| 2015年 | 8278篇 |
| 2014年 | 11947篇 |
| 2013年 | 18099篇 |
| 2012年 | 24480篇 |
| 2011年 | 25569篇 |
| 2010年 | 14909篇 |
| 2009年 | 13964篇 |
| 2008年 | 24249篇 |
| 2007年 | 26311篇 |
| 2006年 | 26210篇 |
| 2005年 | 25806篇 |
| 2004年 | 25349篇 |
| 2003年 | 24304篇 |
| 2002年 | 23370篇 |
| 2001年 | 36984篇 |
| 2000年 | 37726篇 |
| 1999年 | 31997篇 |
| 1998年 | 9709篇 |
| 1997年 | 8963篇 |
| 1996年 | 8859篇 |
| 1995年 | 8385篇 |
| 1994年 | 8076篇 |
| 1992年 | 27478篇 |
| 1991年 | 26947篇 |
| 1990年 | 26388篇 |
| 1989年 | 25452篇 |
| 1988年 | 24002篇 |
| 1987年 | 23547篇 |
| 1986年 | 22403篇 |
| 1985年 | 21723篇 |
| 1984年 | 16918篇 |
| 1983年 | 14453篇 |
| 1982年 | 9150篇 |
| 1981年 | 8474篇 |
| 1980年 | 7940篇 |
| 1979年 | 17242篇 |
| 1978年 | 12501篇 |
| 1977年 | 10504篇 |
| 1976年 | 9649篇 |
| 1975年 | 10434篇 |
| 1974年 | 12974篇 |
| 1973年 | 12457篇 |
| 1972年 | 11819篇 |
| 1971年 | 10939篇 |
| 1970年 | 10449篇 |
| 1969年 | 10139篇 |
| 1968年 | 9135篇 |
| 1967年 | 8437篇 |
| 1966年 | 7839篇 |
排序方式： 共有10000条查询结果，搜索用时 16 毫秒
41.
Dynamic LVOT Obstruction and Aortic Stenosis in the Same Patient: A Case of Challenging Doppler Hemodynamics 
下载免费PDF全文
下载免费PDF全文 Matthew W. Parker M.D. Francis J. Kiernan M.D. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(6):1030-1032
We present a patient with both dynamic left ventricular outflow tract obstruction and valvular aortic stenosis. The aortic valve was calcified, and velocities and gradients measured by continuous‐wave Doppler met standard criteria for severe aortic stenosis. The increased subvalvular velocities invalidated assumptions of the simplified Bernoulli equation; correction using the longer form of the Bernoulli equation suggested a lower but still significant gradient. The complex shape of the subvalvular spectral Doppler envelope indicated supranormal systolic function and dynamic left ventricular outflow obstruction. Left heart catheterization with an end‐hole catheter was required to determine the subvalvular and valvular components of the obstruction. 相似文献
42.
43.
44.
45.
46.
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. O&#x;Brien 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47.
48.
49.
50.