全文获取类型
| 收费全文 | 167297篇 |
| 免费 | 3406篇 |
| 国内免费 | 1628篇 |
专业分类
| 耳鼻咽喉 | 1667篇 |
| 儿科学 | 6183篇 |
| 妇产科学 | 2725篇 |
| 基础医学 | 19210篇 |
| 口腔科学 | 4164篇 |
| 临床医学 | 11274篇 |
| 内科学 | 31963篇 |
| 皮肤病学 | 2938篇 |
| 神经病学 | 9858篇 |
| 特种医学 | 3373篇 |
| 外国民族医学 | 1篇 |
| 外科学 | 26257篇 |
| 综合类 | 9860篇 |
| 一般理论 | 4篇 |
| 预防医学 | 10017篇 |
| 眼科学 | 3278篇 |
| 药学 | 18541篇 |
| 16篇 | |
| 中国医学 | 6157篇 |
| 肿瘤学 | 4845篇 |
出版年
| 2022年 | 1123篇 |
| 2021年 | 2514篇 |
| 2020年 | 1351篇 |
| 2019年 | 12772篇 |
| 2018年 | 12409篇 |
| 2017年 | 5614篇 |
| 2016年 | 1221篇 |
| 2015年 | 1197篇 |
| 2014年 | 3021篇 |
| 2013年 | 4620篇 |
| 2012年 | 2903篇 |
| 2011年 | 2928篇 |
| 2010年 | 2508篇 |
| 2009年 | 2411篇 |
| 2008年 | 2784篇 |
| 2007年 | 3866篇 |
| 2006年 | 4100篇 |
| 2005年 | 3967篇 |
| 2004年 | 3106篇 |
| 2003年 | 3193篇 |
| 2002年 | 3074篇 |
| 2001年 | 3055篇 |
| 2000年 | 3300篇 |
| 1999年 | 2975篇 |
| 1998年 | 3033篇 |
| 1997年 | 2397篇 |
| 1996年 | 2248篇 |
| 1995年 | 2598篇 |
| 1994年 | 2429篇 |
| 1993年 | 1891篇 |
| 1992年 | 1489篇 |
| 1991年 | 1484篇 |
| 1990年 | 1235篇 |
| 1989年 | 978篇 |
| 1988年 | 1014篇 |
| 1987年 | 979篇 |
| 1986年 | 822篇 |
| 1985年 | 5405篇 |
| 1984年 | 7273篇 |
| 1983年 | 5819篇 |
| 1982年 | 6254篇 |
| 1981年 | 5706篇 |
| 1980年 | 4902篇 |
| 1979年 | 4962篇 |
| 1978年 | 4061篇 |
| 1977年 | 3047篇 |
| 1976年 | 3523篇 |
| 1975年 | 2732篇 |
| 1974年 | 2526篇 |
| 1973年 | 2226篇 |
排序方式： 共有10000条查询结果，搜索用时 159 毫秒
41.
F. Giovanardi F. Nudo Q. Lai M. Garofalo A. Consolo E. Choppin De Janvry G.A. Arroyo Murillo P. Ursi D. Stabile F. Melandro P.B. Berloco R. Pretagostini L. Poli 《Transplantation proceedings》2019,51(1):128-131
Background
Arterial vascular anomalies in patients undergoing kidney transplantation (KT) are correlated with a higher incidence of early surgical complications, potentially causing graft loss. Arterial reconstruction allows patients to overcome these surgical challenges, thus minimizing the risk of poor outcomes. The aim of the present study is to retrospectively investigate the safety and effectiveness of the multiple arterial reconstruction technique with a Teflon patch in case of an unavailable aortic patch: to do so, surgical complications, graft function, and patient survival were evaluated.Methods
During the period January 2009 to August 2016, 202 adult deceased-donor KTs were performed at our center. Group A (n = 27; reconstruction of multiple arteries) and Group B (n = 175; control group) were compared.Results
No differences were observed between the 2 groups in terms of early postoperative course, with no vascular complication observed in Group A. No vascular patch infections were reported, nor longer cold ischemia time rates. Similarly, long-term survival rates were similar between the 2 groups.Conclusions
The Teflon-patch arterial reconstruction technique appears to be safe and effective, with an acceptable balance of benefits and potential risks of using a prosthetic material. Studies based on larger series are needed to further validate this approach. 相似文献42.
43.
44.
45.
46.
47.
Khaled Adil Marija Popovic Fabio L. Cury Sergio L. Faria Marie Duclos Luis Souhami 《Practical radiation oncology》2019,9(1):24-28
Purpose
This study aimed to investigate 3 planning target volume (PTV) margin expansions and determine the most appropriate volume to be used in bladder preservation therapy when using daily cone beam computed tomography (CBCT). We aimed to establish whether a smaller PTV expansion is feasible without risking geographical miss.Methods and materials
The study included patients with bladder cancer who were treated with a hypofractionated course of radiation therapy delivered with intensity modulated radiation therapy. The clinical target volume (CTV) was the whole empty bladder, and the PTV consisted of a 1.5-cm margin around the bladder (PTV1.5 cm). Patients underwent daily CBCT imaging before treatment to assess the bladder volume and ensure accurate positioning. We investigated 2 additional smaller PTV margin expansions to determine the most appropriate volume to be used with CBCT as a daily image guided radiation therapy modality. These margins were created retrospectively on every CBCT. The first additional volume was a uniform PTV margin of the surrounding 1 cm (PTV1 cm). When considering that the majority of the internal bladder movement was due to the variation in filling that occurs in the superior and anterior directions, a second volume of an anisotropic PTV margin with a 1.5-cm superior/anterior and 1 cm in other directions (PTV1/1.5 cm) was created. We recorded the frequency and measured the volume of bladder falling out of each PTV based on the daily CBCT.Results
For the purpose of this study, we considered an arbitrary 5 cm3 of CTV falling out of the designated PTV as a clinically significant volumetric miss. The frequency of such a miss when applying the uniform PTV1 cm was 1%. However, when applying the uniform PTV1.5 cm and anisotropic PTV1/1.5 cm margins, the frequency was 0.5% and 0.5%, respectively.Conclusions
The anisotropic PTV expansion of 1.5 cm superiorly and anteriorly and 1 cm in all other directions around the bladder (CTV) provides a safe PTV approach when daily CBCT imaging is used to localize an empty bladder. 相似文献48.
49.
50.
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