收费全文 | 78768篇 |
免费 | 2116篇 |
国内免费 | 443篇 |
耳鼻咽喉 | 568篇 |
儿科学 | 864篇 |
妇产科学 | 1409篇 |
基础医学 | 7866篇 |
口腔科学 | 4017篇 |
临床医学 | 5975篇 |
内科学 | 17943篇 |
皮肤病学 | 1497篇 |
神经病学 | 5604篇 |
特种医学 | 1707篇 |
外国民族医学 | 1篇 |
外科学 | 13819篇 |
综合类 | 2972篇 |
现状与发展 | 1篇 |
一般理论 | 5篇 |
预防医学 | 5451篇 |
眼科学 | 1292篇 |
药学 | 5116篇 |
15篇 | |
中国医学 | 2390篇 |
肿瘤学 | 2815篇 |
2024年 | 78篇 |
2023年 | 528篇 |
2022年 | 914篇 |
2021年 | 1905篇 |
2020年 | 1116篇 |
2019年 | 6633篇 |
2018年 | 6510篇 |
2017年 | 3812篇 |
2016年 | 901篇 |
2015年 | 862篇 |
2014年 | 1574篇 |
2013年 | 1652篇 |
2012年 | 1216篇 |
2011年 | 1442篇 |
2010年 | 1235篇 |
2009年 | 962篇 |
2008年 | 979篇 |
2007年 | 940篇 |
2006年 | 841篇 |
2005年 | 689篇 |
2004年 | 564篇 |
2003年 | 588篇 |
2002年 | 419篇 |
2001年 | 476篇 |
2000年 | 365篇 |
1999年 | 363篇 |
1998年 | 209篇 |
1997年 | 203篇 |
1996年 | 169篇 |
1995年 | 179篇 |
1994年 | 154篇 |
1993年 | 132篇 |
1992年 | 144篇 |
1991年 | 115篇 |
1989年 | 85篇 |
1987年 | 80篇 |
1986年 | 73篇 |
1985年 | 3715篇 |
1984年 | 5050篇 |
1983年 | 4591篇 |
1982年 | 4490篇 |
1981年 | 4002篇 |
1980年 | 3383篇 |
1979年 | 3483篇 |
1978年 | 2836篇 |
1977年 | 2106篇 |
1976年 | 2696篇 |
1975年 | 2107篇 |
1974年 | 1810篇 |
1973年 | 1731篇 |
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Areas covered: The many tools developed to measure disease activity in RA, from composite scores and patient-reported outcomes, to laboratory markers and imaging are discussed, with a focus on their utility in guiding therapy and assessing response. The complex issues in measuring disease activity in RA, whether in clinical trials or normal clinical practice, and in the context of national guidelines and recommendations, available time, and resources are considered.
Expert commentary: The key to effective management of RA is the rapid suppression of inflammation, ideally to remission, with maintenance of such remission. The aim is to prevent disability and maximize quality of life. Central to this is the ability to determine disease activity (potentially open to suppression) as opposed to damage (irreversible). A variety of measures are currently available, allowing better assessment of response to treatment. In the future, the development of predictive biomarkers allowing targeting of drugs may revolutionize this field and render the tools of today redundant. 相似文献