全文获取类型
收费全文 | 1336489篇 |
免费 | 114625篇 |
国内免费 | 6364篇 |
专业分类
耳鼻咽喉 | 16706篇 |
儿科学 | 43014篇 |
妇产科学 | 36562篇 |
基础医学 | 183642篇 |
口腔科学 | 36273篇 |
临床医学 | 120713篇 |
内科学 | 278537篇 |
皮肤病学 | 31886篇 |
神经病学 | 110499篇 |
特种医学 | 55541篇 |
外国民族医学 | 274篇 |
外科学 | 210363篇 |
综合类 | 31529篇 |
现状与发展 | 2篇 |
一般理论 | 414篇 |
预防医学 | 106644篇 |
眼科学 | 28085篇 |
药学 | 93711篇 |
5篇 | |
中国医学 | 2227篇 |
肿瘤学 | 70851篇 |
出版年
2018年 | 13377篇 |
2017年 | 10632篇 |
2016年 | 12798篇 |
2015年 | 14298篇 |
2014年 | 19945篇 |
2013年 | 29739篇 |
2012年 | 36238篇 |
2011年 | 38884篇 |
2010年 | 24375篇 |
2009年 | 23908篇 |
2008年 | 36362篇 |
2007年 | 38781篇 |
2006年 | 39909篇 |
2005年 | 38497篇 |
2004年 | 36732篇 |
2003年 | 35822篇 |
2002年 | 33842篇 |
2001年 | 66063篇 |
2000年 | 67923篇 |
1999年 | 56592篇 |
1998年 | 16726篇 |
1997年 | 15017篇 |
1996年 | 16018篇 |
1995年 | 16233篇 |
1994年 | 15099篇 |
1993年 | 14154篇 |
1992年 | 47103篇 |
1991年 | 45752篇 |
1990年 | 43974篇 |
1989年 | 41817篇 |
1988年 | 38759篇 |
1987年 | 38082篇 |
1986年 | 35861篇 |
1985年 | 34637篇 |
1984年 | 26360篇 |
1983年 | 22108篇 |
1982年 | 13847篇 |
1981年 | 12448篇 |
1980年 | 11719篇 |
1979年 | 23548篇 |
1978年 | 17073篇 |
1977年 | 14386篇 |
1976年 | 13183篇 |
1975年 | 13723篇 |
1974年 | 16094篇 |
1973年 | 15397篇 |
1972年 | 14174篇 |
1971年 | 13038篇 |
1970年 | 11882篇 |
1969年 | 11102篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
12.
Deitelzweig Steve Luo Xuemei Nguyen Jennifer L. Malhotra Deepa Emir Birol Russ Cristina Li Xiaoyan Lee Theodore C. Ferri Mauricio Wiederkehr Danny Reimbaeva Maya Barnes Geoffrey D. Piazza Gregory 《Journal of thrombosis and thrombolysis》2022,54(4):696-696
Journal of Thrombosis and Thrombolysis - 相似文献
13.
14.
A Coupled FEM-BEM Approach for the Solution of the Free-Boundary Axi-Symmetric Plasma Equilibrium Problem 下载免费PDF全文
M. Bonotto D. Abate P. Bettini & F. Villone 《Communications In Computational Physics》2022,31(1):27-59
In this paper we present a coupled Finite Element Method – Boundary Element Method (FEM-BEM) approach for the solution of the free-boundary axi-symmetric
plasma equilibrium problem. The proposed method, obtained from an improvement
of the Hagenow-Lackner coupling method, allows to efficiently model the equilibrium
problem in unbounded domains by discretizing only the plasma region; the external
conductors can be modelled either as 2D or 3D models, according to the problem of interest. The paper explores different iterative methods for the solution of the nonlinear
Grad-Shafranov equation, such as Picard, Newton-Raphson and Newton-Krylov, in order to provide a robust and reliable tool, able to handle large-scale problems (e.g. high
resolution equilibria). This method has been implemented in the FRIDA code (FRee-boundary Integro-Differential Axisimmetric – https://github.
om/matteobonotto/
FRIDA), together with a suitable Adaptive Integration Technique (AIT) for the computation of the source term. FRIDA has been successfully tested and validated against
experimental data from RFX-mod device, and numerical equilibria of an ITER-like device. 相似文献
15.
16.
17.
18.
19.
Peter Düking Christoph Zinner Jennifer L. Reed Hans-Christer Holmberg Billy Sperlich 《Scandinavian journal of medicine & science in sports》2020,30(12):2291-2304
Monitoring variations in the functioning of the autonomic nervous system may help personalize training of runners and provide more pronounced physiological adaptations and performance improvements. We systematically reviewed the scientific literature comparing physiological adaptations and/or improvements in performance following training based on responses of the autonomic nervous system (ie, changes in heart rate variability) and predefined training. PubMed, SPORTDiscus, and Web of Science were searched systematically in July 2019. Keywords related to endurance, running, autonomic nervous system, and training. Studies were included if they (a) involved interventions consisting predominantly of running training; (b) lasted at least 3 weeks; (c) reported pre- and post-intervention assessment of running performance and/or physiological parameters; (d) included an experimental group performing training adjusted continuously on the basis of alterations in HRV and a control group; and (e) involved healthy runners. Five studies involving six interventions and 166 participants fulfilled our inclusion criteria. Four HRV-based interventions reduced the amount of moderate- and/or high-intensity training significantly. In five interventions, improvements in performance parameters (3000 m, 5000 m, Loadmax, Tlim) were more pronounced following HRV-based training. Peak oxygen uptake () and submaximal running parameters (eg, LT1, LT2) improved following both HRV-based and predefined training, with no clear difference in the extent of improvement in . Submaximal running parameters tended to improve more following HRV-based training. Research findings to date have been limited and inconsistent. Both HRV-based and predefined training improve running performance and certain submaximal physiological adaptations, with effects of the former training tending to be greater. 相似文献