全文获取类型
收费全文 | 165577篇 |
免费 | 36241篇 |
国内免费 | 6761篇 |
专业分类
耳鼻咽喉 | 2925篇 |
儿科学 | 3178篇 |
妇产科学 | 2926篇 |
基础医学 | 10057篇 |
口腔科学 | 6084篇 |
临床医学 | 35488篇 |
内科学 | 34124篇 |
皮肤病学 | 4041篇 |
神经病学 | 15706篇 |
特种医学 | 6378篇 |
外国民族医学 | 30篇 |
外科学 | 24150篇 |
综合类 | 13419篇 |
现状与发展 | 61篇 |
一般理论 | 8篇 |
预防医学 | 17951篇 |
眼科学 | 4064篇 |
药学 | 8785篇 |
99篇 | |
中国医学 | 4506篇 |
肿瘤学 | 14599篇 |
出版年
2024年 | 985篇 |
2023年 | 6194篇 |
2022年 | 4209篇 |
2021年 | 6503篇 |
2020年 | 8185篇 |
2019年 | 4383篇 |
2018年 | 9298篇 |
2017年 | 9536篇 |
2016年 | 9939篇 |
2015年 | 11129篇 |
2014年 | 14333篇 |
2013年 | 15631篇 |
2012年 | 8819篇 |
2011年 | 9151篇 |
2010年 | 10597篇 |
2009年 | 12058篇 |
2008年 | 7107篇 |
2007年 | 6123篇 |
2006年 | 7195篇 |
2005年 | 5619篇 |
2004年 | 3668篇 |
2003年 | 3341篇 |
2002年 | 2847篇 |
2001年 | 3557篇 |
2000年 | 2842篇 |
1999年 | 3281篇 |
1998年 | 3091篇 |
1997年 | 2886篇 |
1996年 | 2692篇 |
1995年 | 2364篇 |
1994年 | 1694篇 |
1993年 | 1267篇 |
1992年 | 1157篇 |
1991年 | 989篇 |
1990年 | 824篇 |
1989年 | 796篇 |
1988年 | 760篇 |
1987年 | 598篇 |
1986年 | 521篇 |
1985年 | 412篇 |
1984年 | 310篇 |
1983年 | 333篇 |
1982年 | 239篇 |
1981年 | 208篇 |
1980年 | 130篇 |
1979年 | 72篇 |
1978年 | 119篇 |
1977年 | 114篇 |
1976年 | 83篇 |
1972年 | 70篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Objective
The aim of the study was to estimate the effect of the state-based reinsurance programs through the section 1332 State Innovation Waivers on health insurance marketplace premiums and insurer participation.Data Source
2015 to 2022 Robert Wood Johnson Foundation Health Insurance Exchange Compare Datasets.Study Design
An event study difference-in-differences (DD) model separately for each year of implementation and a synthetic control method (SCM) are used to estimate year-by-year effects following program implementation.Data Collection/Extraction Methods
Not applicable.Principal Findings
Reinsurance programs were associated with a decline in premiums in the first year of implementation by 10%–13%, 5%–19%, and 11%–17% for bronze, silver, and gold plans (p < 0.05). There is a trend of sustained declines especially for states that implemented their programs in 2019 and 2020. The SCM analyses suggest some effect heterogeneity across states but also premium declines across most states. There is no evidence that reinsurance programs affected insurer participation.Conclusion
State-based reinsurance programs have the potential to improve the affordability of health insurance coverage. However, reinsurance programs do not appear to have had an effect on insurer participation, highlighting the need for policy makers to consider complementary strategies to encourage insurer participation. 相似文献2.
3.
4.
5.
6.
7.
8.
9.
ObjectiveEach pulmonary segment is an anatomical and functional unit. However, it is fundamentally difficult to precisely distinguish every pulmonary segment using the conventional pulmonary intersegmental planes from computed tomography images. Building arteriopulmonary segments is likely to be an effective way to identify pulmonary segments.MethodsThe thoracic computed tomography images of 40 patients were collected. The anatomic structures of interest were extracted in the transverse, sagittal, and coronal planes using the semi-automated segmentation tools provided by Amira software. The intrapulmonary vessels were subsequently segmented and reconstructed. The distributions of the pulmonary arteries, veins, and bronchi were observed. In patients with pulmonary masses, the mass was also reconstructed.ResultsThe three-dimensional reconstructed images showed the branches of the pulmonary artery ramified up to their eighth order covering the entire lung as well as evident intersegmental gaps without pulmonary arteries. The segmental artery was closely accompanied by the segmental bronchi in 486 pulmonary segments (90% of total number of segments). The size and spatial location of the pulmonary mass within a pulmonary segment were also clearly visible.ConclusionsDemarcation of arteriopulmonary segments can be used to precisely distinguish every pulmonary segment and provide its detailed anatomical structure before pulmonary segmentectomy. 相似文献
10.
目的:探讨牙支持式3D打印导板辅助穿刺卵圆孔射频热凝治疗三叉神经痛术中术后的疗效分析.方法:对2019年1月~2021年5月收治的三叉神经痛患者40人,根据患者需要随机分成2组:A组(对照组),常规按照Hartel前入路法穿刺卵圆孔,进入卵圆孔后,耳-床线定位确定入颅深度后行射频治疗.B组(导板组),采用3D导板,给患者戴上导板固定后,完成穿刺,耳-床线定位确定入颅深度后行射频治疗.分析2组的术前疼痛评分(VAS)术后即刻及术后1月疼痛消失的有效率,手术时间,穿刺次数,并发症,穿刺的偏移程度.结果:与对照组A组比较在术后即刻有效率、术后1月随访有效率比较无统计学差异(P>0.05).在穿刺次数、穿刺偏移率、手术时间、并发症两组间比较有统计学差异(P<0.05).导板与牙齿紧密贴合率100%.结论:3D打印导板应用于穿刺卵圆孔具有明显的优势,可以减少患者创伤,减少X线辐射,减少穿刺偏移,术后疗效肯定,值得广泛应用. 相似文献