收费全文 | 81574篇 |
免费 | 9126篇 |
国内免费 | 5253篇 |
耳鼻咽喉 | 611篇 |
儿科学 | 1447篇 |
妇产科学 | 780篇 |
基础医学 | 7297篇 |
口腔科学 | 1712篇 |
临床医学 | 9962篇 |
内科学 | 9992篇 |
皮肤病学 | 853篇 |
神经病学 | 3711篇 |
特种医学 | 3370篇 |
外国民族医学 | 30篇 |
外科学 | 8292篇 |
综合类 | 17906篇 |
现状与发展 | 15篇 |
一般理论 | 3篇 |
预防医学 | 7016篇 |
眼科学 | 2109篇 |
药学 | 9025篇 |
63篇 | |
中国医学 | 6312篇 |
肿瘤学 | 5447篇 |
2024年 | 113篇 |
2023年 | 1087篇 |
2022年 | 2141篇 |
2021年 | 3626篇 |
2020年 | 3153篇 |
2019年 | 2451篇 |
2018年 | 2571篇 |
2017年 | 2752篇 |
2016年 | 2447篇 |
2015年 | 3675篇 |
2014年 | 4710篇 |
2013年 | 5058篇 |
2012年 | 7136篇 |
2011年 | 7428篇 |
2010年 | 5791篇 |
2009年 | 4910篇 |
2008年 | 5423篇 |
2007年 | 5299篇 |
2006年 | 5042篇 |
2005年 | 4204篇 |
2004年 | 3365篇 |
2003年 | 3106篇 |
2002年 | 2458篇 |
2001年 | 1959篇 |
2000年 | 1493篇 |
1999年 | 1087篇 |
1998年 | 587篇 |
1997年 | 629篇 |
1996年 | 441篇 |
1995年 | 389篇 |
1994年 | 336篇 |
1993年 | 216篇 |
1992年 | 169篇 |
1991年 | 152篇 |
1990年 | 137篇 |
1989年 | 97篇 |
1988年 | 91篇 |
1987年 | 65篇 |
1986年 | 56篇 |
1985年 | 30篇 |
1984年 | 18篇 |
1983年 | 22篇 |
1982年 | 8篇 |
1981年 | 5篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1976年 | 2篇 |
1974年 | 2篇 |
1970年 | 2篇 |
Background
Bone mineral density (BMD) has been found to improve after parathyroidectomy (PTX) in patients with primary hyperparathyroidism. There are few data on the effect of PTX on BMD in normocalcemic and normohormonal primary hyperparathyroidism.Methods
A retrospective analysis of 92 primary hyperparathyroidism patients who underwent PTX between 2004 and 2012 with pre- and post-PTX dual-energy x-ray absorptiometry was performed. Within-person changes in BMD pre- and post-PTX were analyzed using log linear mixed models, stratified by biochemical status.Results
Bone mineral density increased post-PTX in the whole cohort at the lumbar spine (+2.5%), femoral neck (+2.1%), and total hip (+1.9%) and decreased at the one-third radius (–0.9%). On comparison of BMD changes by profile, BMD increased in those with the typical profile at the lumbar spine (3.2%), femoral neck (2.9%), and total hip (2.9%) but declined at the one-third radius (–1.5%). In contrast, BMD improved only at the femoral neck (4.3%) in the normohormonal group and did not change at any site in the normocalcemic group. The typical group had a greater increase in BMD over time at the femoral neck and total hip compared with normocalcemic patients.Conclusion
Our results indicate that the skeletal benefit of PTX was attenuated in normocalcemic and normohormonal patients, suggesting that skeletal changes after PTX may depend on biochemical profile. 相似文献Previous systematic reviews have found a higher sero-prevalence of EBV antibodies in SLE patients compared with controls. Because many studies have been published, there is a need to apply more precise systematic review methods. We examined the association between EBV and SLE patients by conducting a systematic review and meta-analysis of case–control studies that examined the prevalence of EBV antibodies and the DNA-positive rate. We searched the MEDLINE and EMBASE databases from 1966 to 2018 with no language restrictions. The Mantel–Haenszel odds ratios (OR) for EBV antibody sero-positivity were calculated, and meta-analyses were conducted. Quality assessment was performed using a modified version of the Newcastle–Ottawa scale, and 33 studies were included. Most studies found a higher sero-prevalence of VCA IgG and EA IgG in SLE patients compared with controls. Meta-analysis demonstrated a significantly higher OR for sero-positivity to VCA IgG and EA IgG for SLE cases (2.06 [95% confidence interval (CI) 1.30–3.26, p = 0.002] and 7.70, [95% CI 4.64–12.76, p < 0.001], respectively). The overall OR for the DNA-positive rate for SLE patients compared with controls was 3.86 (95% CI 1.52–9.83, p = 0.005). Other antibodies, i.e., VCA IgA/IgM, EBNA IgA, and EA IgA/IgM, also demonstrated a significant difference between SLE patients and controls. These findings support previous systematic reviews; however, publication bias cannot be excluded. The methodological conduct of studies could be improved, particularly when selecting controls and analyses of laboratory conduct.
相似文献