全文获取类型
收费全文 | 7484篇 |
免费 | 232篇 |
国内免费 | 76篇 |
专业分类
耳鼻咽喉 | 62篇 |
儿科学 | 163篇 |
妇产科学 | 55篇 |
基础医学 | 540篇 |
口腔科学 | 238篇 |
临床医学 | 393篇 |
内科学 | 2151篇 |
皮肤病学 | 141篇 |
神经病学 | 220篇 |
特种医学 | 461篇 |
外科学 | 1695篇 |
综合类 | 391篇 |
预防医学 | 249篇 |
眼科学 | 55篇 |
药学 | 311篇 |
中国医学 | 61篇 |
肿瘤学 | 606篇 |
出版年
2024年 | 7篇 |
2023年 | 56篇 |
2022年 | 94篇 |
2021年 | 151篇 |
2020年 | 101篇 |
2019年 | 2099篇 |
2018年 | 1789篇 |
2017年 | 724篇 |
2016年 | 81篇 |
2015年 | 93篇 |
2014年 | 186篇 |
2013年 | 168篇 |
2012年 | 120篇 |
2011年 | 180篇 |
2010年 | 145篇 |
2009年 | 167篇 |
2008年 | 141篇 |
2007年 | 147篇 |
2006年 | 173篇 |
2005年 | 155篇 |
2004年 | 118篇 |
2003年 | 101篇 |
2002年 | 60篇 |
2001年 | 64篇 |
2000年 | 48篇 |
1999年 | 37篇 |
1998年 | 30篇 |
1997年 | 31篇 |
1996年 | 23篇 |
1995年 | 23篇 |
1994年 | 15篇 |
1993年 | 9篇 |
1992年 | 13篇 |
1991年 | 12篇 |
1988年 | 8篇 |
1987年 | 8篇 |
1986年 | 9篇 |
1985年 | 56篇 |
1984年 | 65篇 |
1983年 | 38篇 |
1982年 | 53篇 |
1981年 | 37篇 |
1980年 | 31篇 |
1979年 | 28篇 |
1978年 | 22篇 |
1977年 | 7篇 |
1976年 | 20篇 |
1975年 | 20篇 |
1974年 | 9篇 |
1973年 | 10篇 |
排序方式: 共有7792条查询结果,搜索用时 0 毫秒
1.
Ngai-Yin Chan Chi-Chung Choy Ho-Chuen Yuen Hoi-Fan Chow Ho-Fai Fong 《The Canadian journal of cardiology》2019,35(4):396-404
Background
Persistent iatrogenic atrial septal defect (iASD) is a common but poorly characterized complication after cryoballoon (CB) pulmonary vein isolation (PVI) procedures. We therefore investigate its prevalence, evolution, risk factors, and clinical outcomes in a prospective longitudinal study.Methods
A total of 108 patients (41 women, mean age 57 ± 11.3) underwent CB PVI for AF. Serial transesophageal echocardiography (TEE) was performed 9 months and then annually until 6 years after the procedure to study the characteristics of persistent iASD.Results
Persistent iASD occurred in 33 (30.6%) patients 9 months after CB PVI. Spontaneous closure of iASD was found in 6 (22.2%) and 3 (15.8%) patients 2 and 3 years after the procedures, respectively. No spontaneous closure was observed on 4, 5, and 6-year TEE follow-up. The projected long-term persistence rate of iASD after CB PVI was therefore 20% (30.6% × 0.778 × 0.842). Using multivariate logistic regression, a higher number of cryoapplications (≥ 2 minutes) was the only independent predictor of persistent iASD 9 months after CB PVI (odds ratio [OR] 1.207; 95% confidence interval [CI], 1.033-1.411, P = 0.018). Two (1.9%) patients with significantly larger iASD size than the others (long diameter 12.6 ± 0.8 vs 3.7 ± 1.5 mm, P < 0.001; short diameter 10.9 ± 0.2 vs 3 ± 1.1 mm, P < 0.001) required percutaneous closure because of exertional dyspnea and right ventricular enlargement. Over 129.7 patient-years follow-up, during which iASD persisted, there was no occurrence of neurologic events.Conclusions
Approximately one fifth of patients undergoing CB PVI will have permanently persistent iASD. Patients with defect sizes of greater than 10 mm may need percutaneous closure due to significant left-to-right shunting. 相似文献2.
Conall T. Morgan Brigitte Mueller Varsha Thakur Vitor Guerra Callaghan Jull Luc Mertens Mark Friedberg Fraser Golding Mike Seed Steven E.S. Miner Edgar T. Jaeggi Cedric Manlhiot Lynne E. Nield 《The Canadian journal of cardiology》2019,35(4):453-461
Background
The purpose of the study was to evaluate the association between fetal echocardiographic measurements and the need for intervention (primary coarctation repair, staged coarctation repair, or catheter intervention) in prenatally diagnosed coarctation of the aorta.Methods
A single-centre retrospective cohort study (2005-2015) of 107 fetuses diagnosed with suspected coarctation of the aorta in the setting of an apex-forming left ventricle and antegrade flow across the mitral and aortic valves.Results
Median gestational age at diagnosis was 32 weeks (interquartile range, 23-35 weeks). Fifty-six (52%) did not require any neonatal intervention, 51 patients (48%) underwent a biventricular repair. In univariable analysis, an increase in ascending aorta (AAo) peak Doppler flow velocity (odds ratio [OR], 1.40 [95% confidence interval [CI], 1.05-1.91] per 20 cm/s; P = 0.03) was associated with intervention. No intervention was associated with larger isthmus size (OR, 0.23; P < 0.001), transverse arch diameter (OR, 0.23; P < 0.001), and aortic (OR, 0.72; P = 0.02), mitral (OR, 0.58; P = 0.001), and AAo (OR, 0.53; P < 0.001) z-scores. In multivariable analysis, higher peak AAo Doppler (OR, 2.51 [95% CI, 1.54-4.58] per 20 cm/s; P = 0.001) and younger gestational age at diagnosis (OR, 0.81 [95% CI, 0.70-0.93] per week; P = 0.005) were associated with intervention, whereas a higher AAo z-score (OR, 0.65 [95% CI, 0.43-0.94] per z; P = 0.029) and transverse arch dimension (OR, 0.44 [95% CI, 0.18-0.97]; P = 0.05) decreased the risk of intervention.Conclusions
In prenatally suspected coarctation, the variables associated with intervention comprised smaller AAo and transverse arch size, earlier gestational age at diagnosis, and the additional finding of a higher peak AAo Doppler. 相似文献3.
4.
5.
6.
7.
8.
9.
10.