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   7280篇
  免费   282篇
  国内免费   56篇
耳鼻咽喉   82篇
儿科学   390篇
妇产科学   90篇
基础医学   1425篇
口腔科学   142篇
临床医学   400篇
内科学   646篇
皮肤病学   30篇
神经病学   1396篇
特种医学   71篇
外科学   260篇
综合类   673篇
预防医学   896篇
眼科学   131篇
药学   701篇
  4篇
中国医学   223篇
肿瘤学   58篇
  2023年   121篇
  2022年   172篇
  2021年   255篇
  2020年   179篇
  2019年   247篇
  2018年   170篇
  2017年   199篇
  2016年   193篇
  2015年   180篇
  2014年   383篇
  2013年   436篇
  2012年   341篇
  2011年   417篇
  2010年   342篇
  2009年   355篇
  2008年   322篇
  2007年   310篇
  2006年   321篇
  2005年   247篇
  2004年   217篇
  2003年   184篇
  2002年   147篇
  2001年   129篇
  2000年   143篇
  1999年   120篇
  1998年   95篇
  1997年   74篇
  1996年   82篇
  1995年   104篇
  1994年   83篇
  1993年   82篇
  1992年   71篇
  1991年   70篇
  1990年   51篇
  1989年   60篇
  1988年   64篇
  1987年   46篇
  1986年   40篇
  1985年   83篇
  1984年   66篇
  1983年   44篇
  1982年   53篇
  1981年   49篇
  1980年   50篇
  1979年   35篇
  1978年   31篇
  1977年   29篇
  1975年   22篇
  1974年   18篇
  1972年   20篇
排序方式: 共有7618条查询结果,搜索用时 15 毫秒
1.
The aim of this study was to carry out a retrospective multicentre study comparing the morphological outcome of 8 techniques used for the management of sagittal synostosis versus a large cohort of control patients. Computed tomographic (CT) images were obtained from children CT-scanned for non-craniosynostosis related events (n = 241) and SS patients at preoperative and postoperative follow-up stages (n = 101). No significant difference in morphological outcomes was observed between the techniques considered in this study. However, the majority of techniques showed a tendency for relapse. Further, the more invasive procedures at older ages seem to lead to larger intracranial volume compared to less invasive techniques at younger ages. This study can be a first step towards future multicentre studies, comparing surgical results and offering a possibility for objective benchmarking of outcomes between methods and centres.  相似文献   
2.
3.
We investigated changes in brain function supporting inhibitory control under age-controlled incentivized conditions, separating age- and performance-related activation in an accelerated longitudinal design including 10- to 22-year-olds. Better inhibitory control correlated with striatal activation during neutral trials, while Age X Behavior interactions in the striatum indicated that in the absence of extrinsic incentives, younger subjects with greater reward circuitry activation successfully engage in greater inhibitory control. Age was negatively correlated with ventral amygdala activation during Loss trials, suggesting that amygdala function more strongly mediates bottom-up processing earlier in development when controlling the negative aspects of incentives to support inhibitory control. Together, these results indicate that with development, reward-modulated cognitive control may be supported by incentive processing transitions in the amygdala, and from facilitative to obstructive striatal function during inhibitory control.  相似文献   
4.
中药质量的评控问题是制约中药现代化发展的瓶颈,因此有必要在现有检测方法的基础上结合生物评价,继而更为全面地保证中药质量。生物评价是完善中药质量标准、保证临床功效和安全性评价的重要方法,已成为中药质量标准化发展趋势之一。在此处主要论述了近年来基于生物活性与效应基准的中药质量评价技术和已取得的部分研究进展,同时对目前中药质量生物评价研究与应用中存在的主要问题进行探讨,进一步对其未来应用做出展望,从而更好的对中药质量进行控制。  相似文献   
5.
目的:观测下关、颧髎、"蝶腭"穴的体表位置,及各穴至蝶腭神经节的针刺深度和针刺方向.方法:15具成年男性尸体,面部左右共30侧,对其面侧区进行由浅入深的解剖.以下关、颧髎、"蝶腭"穴各穴针刺至蝶腭神经节方向为穿刺入路,电动钻带克氏针穿刺延伸至对侧区域,坐标定位法测量各穴的对应穿刺点.结果:①体表位置:"蝶腭"穴与颧髎的体表距离为21 mm,与下关的体表距离为17 mm.②各穴针刺蝶腭神经节的深度:下关为49.9 mm,"蝶腭"穴为46.9 mm,颧髎为46.6 mm.③对应穿刺点坐标定位:下关针刺方向为前内上,对应于对侧的太阳和瞳子髎的中点处附近区域,对应穿刺点距对侧丝竹空的距离为17.6 mm;"蝶腭"穴针刺方向为后内上,对应穿刺点与颧弓水平线的距离为33 mm,与目外眦垂直线的距离为42 mm;颧髎针刺方向为后内上,对应穿刺点与两外耳门连线的距离为28 mm,头部正中线旁开62 mm.结论:了解下关、颧髎、"蝶腭"穴的体表位置、针刺深度、针刺方向,为临床针刺蝶腭神经节提供了依据.  相似文献   
6.
Protracted or recurrent pain and inflammation in the early neonatal period may cause long-lasting changes in central neural function. However, more research is necessary to better characterize the long-term behavioral sequelae of such exposure in the neonatal period. Objectives: (1) to study whether timing of postnatal exposure to persistent inflammation alters responsiveness to thermal pain in the adult animal; (2) to assess whether animals experiencing early postnatal chronic inflammation display altered anxiety related behavior; (3) to study the importance of genetic background. Newborn mice (outbred strain, CD1 and F1 hybrid strain, B6C3F1) received an injection of Complete Freund's Adjuvant (CFA) or saline on either postnatal day 1 or 14 (PND1; PND14) into the left hind paw. Pain to radiant heat and anxiety were examined in 12-week-old adult animals. Adult baseline PWL was significantly decreased in CD1 mice exposed to CFA on PND 1 and 14 as compared to their saline treated counterparts. B6C3F1 mice exposed to CFA on PND14 showed markedly reduced baseline PWL compared to the PND14 saline group. Persistent inflammation experienced by B6C3F1 mice on PND1 failed to affect baseline adult thermal responsiveness. Adult mice, CD1 and B6C3F1, displayed low anxiety traits only if they had been exposed to persistent inflammation on PND1 and not on PND14. Our research suggests a role for genetic background in modulating long-term behavioral consequences of neonatal persistent inflammation: the data support the hypothesis that pain experienced very early in life differentially affects adult behavioral and emotional responsiveness in outbred (CD1) and hybrid mice (B6C3F1).  相似文献   
7.
研究大学生心理素质与思想品德发展的关系,目的在于分析、发现个体在接受教育过程中的心理运动规律,从而提高思想教育的实效性。本文从马克思主义认识论和实践论的观点出发,依据教育心理学的原理,探讨了心理健康教育与思想品德教育的内在联系和相互作用,提出良好的心理素质是大学生思想品德发展的基础的观点。认为品德的形成与人的心理活动息息相关,个体如果没有良好的品德,将影响其心理素质的完善;同样,没有健全的心理素质,思想品德也不能得到很好的发展。只有思想品德教育与心理健康教育协调发展,共同作用,才能收到良好的教育效果。  相似文献   
8.
The possible effect of Government Consumption (a component of Gross Domestic Product (GDP)) on attainment of the hunger Millennium Development Goal (MDG1) was analyzed by evaluating the effect of macroeconomic, social, demographic and policy variables on average undernourished population. Eighty-four developing countries with data available on undernourished population were included in an ecological study. Regression models were applied to explore possible determinants of Undernourished between 1990 and 2004 and consequent achievement of the projected 2004 MDG1. In 2004, 1.4% of the overall undernourished population in the studied countries [70.16 million people] was in excess of the projected level required to meet MDG1. The multiple linear regression showed significant associations between Undernourished and poverty levels, the Gini Index, rural population and Government Consumption. The multiple logistic regression showed significant associations between achievement of projected 2004 MDG1 levels and Government Consumption and the Gini Index. The significant associations between Undernourished and Government Consumption suggest that the effects of GDP components on social conditions call for more thorough research and that policymakers such as governments and international financial institutions need to ensure that changes in distributive and redistributive policies do not negatively affect the possibility of achieving MDG1.  相似文献   
9.
刺血术是中医学中一种古老而独特的针刺治疗方法,文章对刺血术的发展进行了概述,并对其历史分期进行了总结。刺血术发展的四个历史阶段是:第一阶段为起源及萌芽阶段(春秋以前),以砭石的出现及其应用标志;第二阶段为理论奠基及经验积累阶段(战国至唐),以《黄帝内经》的问世为其理论体系形成标志;第三阶段为理论创新及特色形成阶段(宋金元),以金元四大家刘完素、张从正、李杲、朱震亨的刺血成就为其代表;第四阶段为不断完善及日趋成熟阶段(明清),以诸医家对瘟毒疫疠的刺血经验为其特征。  相似文献   
10.
Unmet need for contraception represents a major failure in the provision of reproductive health services and reflects the extent of access to services for spacing and limiting births, which are also affected by personal, partner, community and health system factors. In the context of the Millennium Development Goals, family planning has been given insufficient attention compared to maternal health and the control of sexually transmitted infections. As this omission is being redressed, efforts should be directed towards ensuring that an indicator of unmet need is used as a measure of access to services. The availability of data on unmet need must also be increased to enable national comparisons and facilitate resource mobilisation. Unmet need is a vital component in monitoring the proportion of women able to space and limit births. Unmet need for contraception is a measure conditioned by people's preferences and choices and therefore firmly introduces a rights perspective into development discourse and serves as an important instrument to improve the sensitivity of policy dialogue. The new reproductive health target and the opportunity it offers to give appropriate attention to unmet need for contraception will allow the entry of other considerations vital to ensuring universal access to reproductive health.  相似文献   
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