首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2278725篇
  免费   168199篇
  国内免费   3682篇
耳鼻咽喉   33517篇
儿科学   77697篇
妇产科学   65217篇
基础医学   328524篇
口腔科学   63325篇
临床医学   197948篇
内科学   446887篇
皮肤病学   48983篇
神经病学   177751篇
特种医学   90005篇
外国民族医学   973篇
外科学   350703篇
综合类   49078篇
现状与发展   1篇
一般理论   632篇
预防医学   171040篇
眼科学   51958篇
药学   171401篇
  3篇
中国医学   4406篇
肿瘤学   120557篇
  2018年   22331篇
  2016年   18832篇
  2015年   21445篇
  2014年   29829篇
  2013年   45637篇
  2012年   62515篇
  2011年   66670篇
  2010年   39718篇
  2009年   37660篇
  2008年   64151篇
  2007年   69205篇
  2006年   69874篇
  2005年   68264篇
  2004年   66333篇
  2003年   64191篇
  2002年   63133篇
  2001年   105757篇
  2000年   109212篇
  1999年   92952篇
  1998年   26148篇
  1997年   23497篇
  1996年   23878篇
  1995年   22643篇
  1994年   21434篇
  1993年   19864篇
  1992年   74442篇
  1991年   73133篇
  1990年   71731篇
  1989年   68994篇
  1988年   64015篇
  1987年   62913篇
  1986年   59280篇
  1985年   56796篇
  1984年   42680篇
  1983年   36387篇
  1982年   21557篇
  1981年   19342篇
  1980年   17746篇
  1979年   39328篇
  1978年   27498篇
  1977年   23639篇
  1976年   22263篇
  1975年   24255篇
  1974年   28494篇
  1973年   27453篇
  1972年   25783篇
  1971年   23731篇
  1970年   22269篇
  1969年   20860篇
  1968年   19380篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Molnár  B.  Aroca  S.  Dobos  A.  Orbán  K.  Szabó  J.  Windisch  P.  Stähli  A.  Sculean  A. 《Clinical oral investigations》2022,26(12):7135-7142
Clinical Oral Investigations - To evaluate t he long-term outcomes following treatment of RT 1 multiple adjacent gingival recessions (MAGR) using the modified coronally advanced tunnel (MCAT) with...  相似文献   
2.
3.
4.
5.
6.
7.
Vaccination is a vital health care initiative to prevent individual and population infection. To increase vaccination rates the federal government implemented the ‘No Jab, No Pay’ policy, where eligibility for several government benefits required children to be fully vaccinated by removing ‘conscientious objections’ and expanding the age range of children whose families receive benefits. This study assesses the impact of this policy at a local area within a single medical practice community in NSW, Australia. A retrospective clinical audit was performed between 2012 and 2017 on a single general practice's vaccination records for children ≤19 years. Catch-up vaccinations were assessed based on age at vaccination. Incidence of catch-up vaccinations was assessed for each of four years before and two years after the implementation of the ‘No Jab, No Pay’ policy in January 2016, along with the age of children and vaccination(s) given. Catch-up vaccinations were assessed temporally either side of implementation of ‘No Jab, No Pay’. Comparing the average annual vaccination catch-up incidence rate of 6.2% pre-implementation (2012–2015), there was an increase to 9.2% in 2016 (p < .001) and 7.8% in 2017 (p = .027). Secondary outcome measurement of catch-up vaccination incidence rates before (2012–2015) and after (2016–2017) ‘No Jab, No Pay’ implementation showed statistically significant increases for children aged 8–11 years (3.2%–5.6%, p = .038), 12–15 years (7.5%–14.7%, p < .001) and 16–19 years (3.3%–10.2%, p < .001) along with a statistically significant reduction in children aged 1–3 years (11.4%–6.2%, p = .015). Also, catch-up rates for DTPa significantly increased after program implementation. This study demonstrates that the Australian federal government vaccination policy ‘No Jab, No Pay’ was coincident with an increase in catch-up vaccinations within a rural NSW community served by one medical practice, especially for older children.  相似文献   
8.
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   
9.
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号