全文获取类型
收费全文 | 15108篇 |
免费 | 1244篇 |
国内免费 | 329篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 312篇 |
妇产科学 | 43篇 |
基础医学 | 579篇 |
口腔科学 | 37篇 |
临床医学 | 2731篇 |
内科学 | 7317篇 |
皮肤病学 | 9篇 |
神经病学 | 186篇 |
特种医学 | 557篇 |
外科学 | 1626篇 |
综合类 | 1886篇 |
现状与发展 | 1篇 |
预防医学 | 239篇 |
眼科学 | 16篇 |
药学 | 682篇 |
4篇 | |
中国医学 | 352篇 |
肿瘤学 | 91篇 |
出版年
2024年 | 22篇 |
2023年 | 337篇 |
2022年 | 452篇 |
2021年 | 809篇 |
2020年 | 775篇 |
2019年 | 853篇 |
2018年 | 716篇 |
2017年 | 484篇 |
2016年 | 373篇 |
2015年 | 499篇 |
2014年 | 1031篇 |
2013年 | 894篇 |
2012年 | 687篇 |
2011年 | 835篇 |
2010年 | 650篇 |
2009年 | 657篇 |
2008年 | 728篇 |
2007年 | 802篇 |
2006年 | 581篇 |
2005年 | 571篇 |
2004年 | 402篇 |
2003年 | 395篇 |
2002年 | 298篇 |
2001年 | 341篇 |
2000年 | 279篇 |
1999年 | 270篇 |
1998年 | 238篇 |
1997年 | 214篇 |
1996年 | 164篇 |
1995年 | 173篇 |
1994年 | 141篇 |
1993年 | 124篇 |
1992年 | 102篇 |
1991年 | 111篇 |
1990年 | 88篇 |
1989年 | 62篇 |
1988年 | 51篇 |
1987年 | 50篇 |
1986年 | 56篇 |
1985年 | 49篇 |
1984年 | 66篇 |
1983年 | 49篇 |
1982年 | 49篇 |
1981年 | 25篇 |
1980年 | 41篇 |
1979年 | 23篇 |
1978年 | 23篇 |
1977年 | 11篇 |
1976年 | 11篇 |
1974年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
Dynamic LVOT Obstruction and Aortic Stenosis in the Same Patient: A Case of Challenging Doppler Hemodynamics
下载免费PDF全文
![点击此处可从《Echocardiography (Mount Kisco, N.Y.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
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
4.
Feasibility and Diagnostic Potential of Pulmonary Transit Time Measurement by Contrast Echocardiography: A Pilot Study
下载免费PDF全文
![点击此处可从《Echocardiography (Mount Kisco, N.Y.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
5.
6.
7.
8.
9.
10.
《JACC: Cardiovascular Interventions》2022,15(7):741-750
ObjectivesThe aim of this study was to report 1-year clinical outcomes following commercial transcatheter left atrial appendage occlusion (LAAO) in the United States.BackgroundThe National Cardiovascular Data Registry LAAO Registry was initiated to meet a condition of Medicare coverage and allow the assessment of clinical outcomes. The 1-year rates of thromboembolic events after transcatheter LAAO in such a large cohort of “real-world” patients have not been previously reported.MethodsPatients entered into the National Cardiovascular Data Registry LAAO Registry for a Watchman procedure between January 1, 2016, and December 31, 2018, were included. The primary endpoint was ischemic stroke. Key secondary endpoints included the rate of ischemic stroke or systemic embolism, mortality, and major bleeding. Major bleeding was defined as any bleeding requiring hospitalization, and/or causing a decrease in hemoglobin level > 2g/dL, and/or requiring blood transfusion that was not hemorrhagic stroke. The Kaplan-Meier method was used for 1-year estimates of cumulative event rates.ResultsThe study population consisted of 36,681 patients. The mean age was 76.0 ± 8.1 years, the mean CHA2DS2-VASc score was 4.8 ± 1.5, and the mean HAS-BLED score was 3.0 ± 1.1. Prior stroke was present in 25.5%, clinically relevant bleeding in 69.5%, and intracranial bleeding in 11.9%. Median follow-up was 374 days (IQR: 212-425 days). The Kaplan-Meier–estimated 1-year rate of ischemic stroke was 1.53% (95% CI: 1.39%-1.69%), the rate of ischemic stroke or systemic embolism was 2.19% (95% CI: 2.01%-2.38%), and the rate of mortality was 8.52% (95% CI: 8.19%-8.87%). The 1-year estimated rate of major bleeding was 6.93% (95% CI: 6.65%-7.21%). Most bleeding events occurred between discharge and 45 days following the procedure.ConclusionsThis study characterizes important outcomes in a national cohort of patients undergoing transcatheter LAAO in the United States. Clinicians and patients can integrate these data in shared decision making when considering this therapy. 相似文献