全文获取类型
收费全文 | 61510篇 |
免费 | 5225篇 |
国内免费 | 141篇 |
专业分类
耳鼻咽喉 | 565篇 |
儿科学 | 2324篇 |
妇产科学 | 1607篇 |
基础医学 | 8622篇 |
口腔科学 | 1354篇 |
临床医学 | 8738篇 |
内科学 | 11719篇 |
皮肤病学 | 1175篇 |
神经病学 | 6023篇 |
特种医学 | 1390篇 |
外科学 | 5886篇 |
综合类 | 692篇 |
一般理论 | 80篇 |
预防医学 | 7772篇 |
眼科学 | 835篇 |
药学 | 3619篇 |
2篇 | |
中国医学 | 60篇 |
肿瘤学 | 4413篇 |
出版年
2023年 | 509篇 |
2022年 | 594篇 |
2021年 | 1510篇 |
2020年 | 1132篇 |
2019年 | 1719篇 |
2018年 | 1848篇 |
2017年 | 1461篇 |
2016年 | 1611篇 |
2015年 | 1739篇 |
2014年 | 2241篇 |
2013年 | 3274篇 |
2012年 | 4606篇 |
2011年 | 4692篇 |
2010年 | 2564篇 |
2009年 | 2264篇 |
2008年 | 3819篇 |
2007年 | 3953篇 |
2006年 | 3926篇 |
2005年 | 3727篇 |
2004年 | 3516篇 |
2003年 | 3360篇 |
2002年 | 3021篇 |
2001年 | 622篇 |
2000年 | 529篇 |
1999年 | 581篇 |
1998年 | 707篇 |
1997年 | 534篇 |
1996年 | 467篇 |
1995年 | 455篇 |
1994年 | 371篇 |
1993年 | 380篇 |
1992年 | 384篇 |
1991年 | 352篇 |
1990年 | 315篇 |
1989年 | 296篇 |
1988年 | 298篇 |
1987年 | 233篇 |
1986年 | 252篇 |
1985年 | 262篇 |
1984年 | 246篇 |
1983年 | 197篇 |
1982年 | 210篇 |
1981年 | 211篇 |
1980年 | 165篇 |
1979年 | 154篇 |
1978年 | 151篇 |
1977年 | 117篇 |
1976年 | 113篇 |
1974年 | 99篇 |
1973年 | 118篇 |
排序方式: 共有10000条查询结果,搜索用时 97 毫秒
1.
2.
3.
Dongbing Lai Emma C. Johnson Sarah Colbert Gayathri Pandey Grace Chan Lance Bauer Meredith W. Francis Victor Hesselbrock Chella Kamarajan John Kramer Weipeng Kuang Sally Kuo Samuel Kuperman Yunlong Liu Vivia McCutcheon Zhiping Pang Martin H. Plawecki Marc Schuckit Jay Tischfield Leah Wetherill Yong Zang Howard J. Edenberg Bernice Porjesz Arpana Agrawal Tatiana Foroud 《Alcoholism, clinical and experimental research》2022,46(3):374-383
4.
5.
Ingmar Fleps Pierre Guy Stephen J Ferguson Peter A Cripton Benedikt Helgason 《Journal of bone and mineral research》2019,34(10):1837-1850
The majority of hip fractures in the elderly are the result of a fall from standing or from a lower height. Current injury models focus mostly on femur strength while neglecting subject-specific loading. This article presents an injury modeling strategy for hip fractures related to sideways falls that takes subject-specific impact loading into account. Finite element models (FEMs) of the human body were used to predict the experienced load and the femoral strength in a single model. We validated these models for their predicted peak force, effective pelvic stiffness, and fracture status against matching ex vivo sideways fall impacts (n = 11) with a trochanter velocity of 3.1 m/s. Furthermore, they were compared to sideways impacts of volunteers with lower impact velocities that were previously conducted by other groups. Good agreement was found between the ex vivo experiments and the FEMs with respect to peak force (root mean square error [RMSE] = 10.7%, R2 = 0.85) and effective pelvic stiffness (R2 = 0.92, RMSE = 12.9%). The FEMs were predictive of the fracture status for 10 out of 11 specimens. Compared to the volunteer experiments from low height, the FEMs overestimated the peak force by 25% for low BMI subjects and 8% for high BMI subjects. The effective pelvic stiffness values that were derived from the FEMs were comparable to those derived from impacts with volunteers. The force attenuation from the impact surface to the femur ranged between 27% and 54% and was highly dependent on soft tissue thickness (R2 = 0.86). The energy balance in the FEMS showed that at the time of peak force 79% to 93% of the total energy is either kinetic or was transformed to soft tissue deformation. The presented FEMs allow for direct discrimination between fracture and nonfracture outcome for sideways falls and bridge the gap between impact testing with volunteers and impact conditions representative of real life falls. © 2019 American Society for Bone and Mineral Research. 相似文献
6.
7.
Susan E. Hickman Alexia M. Torke Greg A. Sachs Rebecca L. Sudore Anne L. Myers Qing Tang Giorgos Bakoyannis Bernard J. Hammes 《Journal of pain and symptom management》2019,57(6):1143-1150.e5
ContextIt is especially important that patients are well informed when making high-stakes, preference-sensitive decisions like those on the Physician Orders for Life-Sustaining Treatment (POLST) form. However, there is currently no way to easily evaluate whether patients understand key concepts when making these important decisions.ObjectivesTo develop a POLST knowledge survey.MethodsExpert (n = 62) ratings of key POLST facts were used to select items for a POLST knowledge survey. The survey was administered to nursing facility residents (n = 97) and surrogate decision-makers (n = 112). A subset (n = 135) were re-administered the survey after a standardized advance care planning discussion to assess the scale's responsiveness to change.ResultsThe 19-item survey demonstrated adequate reliability (α = 0.72.). Residents' scores (x = 11.4, standard deviation 3.3) were significantly lower than surrogate scores (x = 14.7, standard deviation 2.5) (P < 0.001). Scores for both groups increased significantly after administration of a standardized advance care planning discussion (P < 0.001). Although being a surrogate, age, race, education, cognitive functioning, and health literacy were significantly associated with higher POLST Knowledge Survey scores in univariate analyses, only being a surrogate (P < 0.001) and being white (P = 0.028) remained significantly associated with higher scores in multivariate analyses.ConclusionThe 19-item POLST Knowledge Survey demonstrated adequate reliability and responsiveness to change. Findings suggest the survey could be used to identify knowledge deficits and provide targeted education to ensure adequate understanding of key clinical decisions when completing POLST. 相似文献
8.
9.
10.