全文获取类型
收费全文 | 219篇 |
免费 | 6篇 |
国内免费 | 5篇 |
专业分类
儿科学 | 4篇 |
妇产科学 | 1篇 |
基础医学 | 7篇 |
临床医学 | 22篇 |
内科学 | 120篇 |
特种医学 | 13篇 |
外科学 | 18篇 |
综合类 | 18篇 |
预防医学 | 4篇 |
药学 | 20篇 |
中国医学 | 3篇 |
出版年
2023年 | 5篇 |
2022年 | 3篇 |
2021年 | 5篇 |
2020年 | 8篇 |
2019年 | 9篇 |
2018年 | 6篇 |
2017年 | 5篇 |
2016年 | 2篇 |
2015年 | 1篇 |
2014年 | 14篇 |
2013年 | 11篇 |
2012年 | 7篇 |
2011年 | 19篇 |
2010年 | 12篇 |
2009年 | 6篇 |
2008年 | 8篇 |
2007年 | 7篇 |
2006年 | 9篇 |
2005年 | 5篇 |
2004年 | 8篇 |
2003年 | 9篇 |
2002年 | 11篇 |
2001年 | 9篇 |
2000年 | 7篇 |
1999年 | 6篇 |
1998年 | 8篇 |
1997年 | 6篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1993年 | 4篇 |
1992年 | 5篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1984年 | 1篇 |
排序方式: 共有230条查询结果,搜索用时 46 毫秒
1.
2.
《JACC: Cardiovascular Imaging》2020,13(12):2561-2572
ObjectivesThe aim of this study was to investigate the relationship between extracellular volume fraction (ECV), a noninvasive parameter that quantifies the degree of diffuse myocardial fibrosis on cardiac magnetic resonance (CMR), and left ventricular diastolic dysfunction (LVDD) in patients with aortic stenosis (AS).BackgroundMyocardial fibrosis on invasive myocardial biopsy is associated with LVDD. However, there is a paucity of data on the association between noninvasively quantified diffuse myocardial fibrosis and the degree of LVDD and how these are related to symptoms and long-term prognosis in patients with AS.MethodsPatients with moderate or severe AS (n = 191; mean age 68.4 years) and 30 control subjects without cardiovascular risk factors underwent CMR. LVDD grade was evaluated using echocardiography according to the 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging guidelines. Clinical outcomes were defined as a composite of all-cause mortality or hospitalization for heart failure aggravation.ResultsPatients in higher ECV quintiles had a significantly higher prevalence of LVDD. Higher ECV was particularly associated with decreased myocardial relaxation (septal e′ <7 cm/s) and increased LV filling pressure (E/e′ ratio ≥15). Although both impaired diastolic function and higher ECV were significantly associated with a worse degree of dyspnea, patients with higher ECV showed greater dyspnea within the same grade of LVDD. During a median follow-up period of 5.6 years, 37 clinical events occurred. Increased ECV, as well as lower septal e′ and higher E/septal e′ ratio, were independent predictors of clinical events, irrespective of age, AS severity, aortic valve replacement, and left ventricular (LV) ejection fraction. ECV provided incremental prognostic value on top of clinical factors and LV systolic and diastolic function.ConclusionsDiffuse myocardial fibrosis, assessed using ECV on CMR, was associated with LVDD in patients with AS, but both ECV and LV diastolic function parameters provided a complementary explanation for dyspnea and clinical outcomes. Concomitant assessment of both LVDD and diffuse myocardial fibrosis may further identify patients with AS with greater symptoms and worse prognosis. 相似文献
3.
4.
Several indices are available to assess left ventricular (LV) function. Although ejection fraction (EF) is widely used, it has many limitations. An assessment of LV longitudinal function should be therefore provided as it precedes the impairment of EF. In this context, speckle tracking derived global longitudinal strain is the gold standard but S’ velocity of mitral annulus (by pulsed tissue Doppler) and mitral annular plane systolic excursion (by M-mode) represent more than simple surrogates. LV diastolic assessment should be oriented not to the simple classification of transmitral patterns (E/A ratio and E velocity deceleration time) but to non-invasive estimation of LV filling pressures. This can be mainly obtained from E/e’ ratio, with additional calculation of other measurements such as pulmonary flow atrial reverse velocity, systolic pulmonary arterial pressure and left atrial volume index. This comprehensive assessment could also be useful to differentiate heart failure with reduced and preserved EF in particular. 相似文献
5.
6.
大鼠离体心脏缺血-再灌注过程的功能变化 总被引:1,自引:0,他引:1
目的 建立大鼠离体心脏缺血-再灌注(I/R)损伤模型,观察I/R过程心脏舒缩功能与冠脉流量变化. 方法 大鼠离体心脏采用Langendorff法灌流,对照组(n=8)心脏连续灌流80 min;I/R组(n=8)心脏缺血40 min再灌注40 min.实验过程实时动态检测心率(min-1)、心肌收缩幅度(g)与最大收缩速度(dT/dtmax,g/ms)、最大舒张速度(-dT/dtmax,g/ms)、心肌静息张力(g)、冠脉流量(液滴,min-1). 结果 与对照组比较,I/R组心脏缺血后心搏停止,20 min后心肌静息张力上升(P<0.05);再灌注后心肌张力仍高;心搏恢复但心率、心脏收缩幅度、最大收缩速度、最大舒张速度均降低(P<0.05~0.001);再复灌注初冠脉流量恢复正常,10 min后呈下降性变化(P<0.05~0.001). 结论 大鼠离体心脏缺血40 min再灌注40 min导致I/R损伤,该模型制备及功能评价方法简便可靠. 相似文献
7.
8.
Cardiomyopathiesarediseasesofheartmusclethatareassociatedwithcardiacdysfunction.Molecularge-neticstudiesperformedtodatehavedemonstratedthatthedamageormutationsinseveralsarcomericcontractileproteingenesareassociatedwiththedevelopmentofthediseases.Inthisreview,cardiactroponinI,oneofthesarcomericthinfilamentprotein,willbediscussedregardingitsroleincardiacfunction,itsdeficiency-relateddiastolicdysfunction,andthemutationofthisprotein-mediatedrestrictivecardiomyopathy.INTRODUCTIONHeartfailureis… 相似文献
9.
10.