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   870篇
  免费   126篇
  国内免费   22篇
耳鼻咽喉   17篇
儿科学   18篇
妇产科学   6篇
基础医学   120篇
口腔科学   14篇
临床医学   73篇
内科学   74篇
皮肤病学   7篇
神经病学   71篇
特种医学   120篇
外科学   17篇
综合类   128篇
预防医学   139篇
眼科学   26篇
药学   69篇
  3篇
中国医学   83篇
肿瘤学   33篇
  2024年   1篇
  2023年   10篇
  2022年   28篇
  2021年   47篇
  2020年   46篇
  2019年   29篇
  2018年   21篇
  2017年   32篇
  2016年   40篇
  2015年   31篇
  2014年   67篇
  2013年   75篇
  2012年   46篇
  2011年   65篇
  2010年   41篇
  2009年   32篇
  2008年   49篇
  2007年   43篇
  2006年   40篇
  2005年   22篇
  2004年   31篇
  2003年   25篇
  2002年   21篇
  2001年   19篇
  2000年   7篇
  1999年   16篇
  1998年   16篇
  1997年   16篇
  1996年   7篇
  1995年   10篇
  1994年   5篇
  1993年   9篇
  1992年   4篇
  1991年   8篇
  1990年   5篇
  1989年   3篇
  1988年   5篇
  1987年   3篇
  1986年   2篇
  1985年   16篇
  1984年   4篇
  1983年   5篇
  1981年   5篇
  1980年   2篇
  1979年   2篇
  1978年   2篇
  1977年   2篇
  1976年   1篇
  1975年   2篇
排序方式: 共有1018条查询结果,搜索用时 218 毫秒
111.
The historical background of aneurysmal subarachnoid hemorrhage is depicted with emphasis in the Scandinavian contribution to improvements in the treatment. It is concluded that an aneurysmal subarachnoid hemorrhage with all certainty was the cause of death of the prospective King of Sweden, Charles August, in the year 1810. Despite advances in management and surgical treatment of this devastating disease the outcome in this important patient-which led to a new royal dynasty in Sweden-would certainly have turned out as fatal today as became the case 174 years ago.  相似文献   
112.
孕妇七情背景及七情生活事件的研究   总被引:3,自引:3,他引:0  
采用笔者编制的“七情发病背景量表”和“七情生活事件表”,对22例孕妇及66例正常人进行七情状况调查。发现孕妇七情背景中“忧”、“悲”、“恐”、“惊”较正常人多,有极显著性差异;正常人中“喜”的情绪倾向较多,与孕妇有极显著性差异。孕妇因妊娠和生产过程中的种种生活事件所致的“恐”、“惊”、“怒”、“忧”4种情绪也明显高于常人,其中“恐”分值高出3倍以上,提示孕妇存在较明显的负性情绪,为有针对性地调节孕期七情提供了临床理论依据。  相似文献   
113.
本文用放射化学分析和半导体α-谱仪测量的新技术分析测定了广东高本底地区和对照地区民肺蛆织中天然放射性钍同位索的舍量, 并估算了对肺组织的剂量。  相似文献   
114.
我国阳江高本底地区由于地丧中含有弛居石矿物而茛辐射本底有所增高。测定表明: 室内、外空气出平均222Rn浓度分别为31.8和16.4Bqm-3, 为对照地区的2.9和1.5倍, 平均222Rn浓度分别为167.5和18.1Bqm-3, 为对照地区的9.6和1.8倍; 室内、外空气中平均222Rn子体α潜能浓度分别为0.1积0.907μJm-3, 为对照地区的2.6和2.2倍, 平均212Pb÷212Biα潜能浓度分别为0.255和0.053μJm-3, 为对照地区的3.7和2.7倍。阳江高率底地区居民吸入222Rn、222Rn及其子体年平均有效剂量当量为2.8mSv, 约为对黑地区和全球正常本底地区的3倍, 其中10.5%来自220Rn及其子体。  相似文献   
115.
Objectives: To investigate the association between certain socio‐demographic characteristics and dental health status of 5‐ to 12‐year‐old children attending public kindergarten and primary schools in Piraeus, Greece. Methods: Gender, age, place of residence, immigrant background and area‐based income were associated with dental caries prevalence, treatment needs and oral hygiene level in 5,116 children. Results: The mean number of decayed, missing and filled deciduous teeth (dmft) and Unmet Restorative Treatment Needs Index (UTN) at 6‐year‐olds were 1.54 and 84.6% respectively, and the DMFT and UTN at 12‐year‐olds were 1.35 and 71.8%. Caries experience/severity significantly increased with age, whereas treatment needs and oral hygiene level decreased (P < 0.001). Immigrant background and low area‐based income was associated with poorer oral health outcomes. The above associations retained statistical significance after multivariate analysis. Children who live in areas with lower average income present 1.20 to 2.14 greater risk of having higher caries severity and poorer oral hygiene in comparison to those living in more affluent areas, and children with an immigrant background have 1.68 to 4.34 higher likelihood to present higher dmft and DMFT values, higher unmet treatment needs, and poorer oral hygiene levels compared to their Greek counterparts above and beyond the effect of the other risk factors assessed. Conclusions: The present study revealed a socio‐demographic gradient in oral health status and treatment needs of children in Piraeus, Greece.  相似文献   
116.
目的准确分析线圈参数变化对经颅磁刺激下大脑内电磁场的影响。方法利用真实头模型和有限元方法,对经颅磁刺激下电磁场环境建模,结合实际电路进行电路电磁场耦合分析。结果以此为理论基础设计出自动后台仿真系统,实现对线圈电磁场的自动分析,设计出参数获取系统自动获取满足临床刺激需要,并可用于实际制作的线圈参数。结论线圈设计系统能为临床磁刺激仪使用者分析大脑内电磁场和设计线圈提供指导意见。  相似文献   
117.
Background noise (BGN) can affect performance of various tasks as a function of its intensity. Such effects may involve modulation of arousal level during task performance, though the neural mechanisms responsible for the intensity-dependence of effects of BGN are still unclear in detail. We examined the effects of BGN (white noise) of various intensities (control, < 40 dB without BGN; 70 dB; 100 dB) during maze task on neuronal activity related to arousal and stress responses using c-Fos immunohistochemistry in rats. Performance (number of errors, time to goal, and number of rearings) during the maze task under 70 dB-BGN, but not 100 dB-BGN, was improved compared with the control condition. In addition, 70 dB-BGN increased c-Fos expression in brain areas responsible for arousal, including mesopontine tegmentum, basal forebrain (BF), locus coeruleus (LC), and cortex, whereas 100 dB-BGN markedly activated neurons in stress-related nuclei, such as the hypothalamic paraventricular nucleus, central nucleus and basolateral nucleus of the amygdala, as well as BF cholinergic neurons, LC neurons, and cortex. These findings suggest that BGN during maze task can induce differential neuronal activation depending on the intensity of BGN in the brain areas relating to arousal and stress responses, which might be involved in maze performance.  相似文献   
118.
Many new targeted small molecule anticancer kinase inhibitors are actively being developed. However, the clinical use of some kinase inhibitors has been shown to result in cardiotoxicity. In most cases the mechanisms by which they exert their cardiotoxicity are not well understood. We have used large scale profiling data on 8 FDA-approved tyrosine kinase inhibitors and 10 other kinase inhibitors to a panel of 317 kinases in order to correlate binding constants and kinase inhibitor binding selectivity scores with kinase inhibitor-induced damage to neonatal rat cardiac myocytes. The 18 kinase inhibitors that were the subject of this study were: canertinib, dasatinib, dovitinib, erlotinib, flavopiridol, gefitinib, imatinib, lapatinib, midostaurin, motesanib, pazopanib, sorafenib, staurosporine, sunitinib, tandutinib, tozasertib, vandetanib and vatalanib. The combined tyrosine kinase and serine-threonine kinase selectivity scores were highly correlated with the myocyte-damaging effects of the kinase inhibitors. This result suggests that myocyte damage was due to a lack of target selectivity to binding of both tyrosine kinases and serine-threonine kinases, and was not due to binding to either group specifically. Finally, the strength of kinase inhibitor binding for 290 kinases was examined for correlations with myocyte damage. Kinase inhibitor binding was significantly correlated with myocyte damage for 12 kinases. Thus, myocyte damage may be multifactorial in nature with the inhibition of a number of kinases involved in producing kinase inhibitor-induced myocyte damage.  相似文献   
119.
火神派是形成于清末的一个医学流派,他从一开始就充满了非议,该文试图从影响火神派形成的各种因素入手,进一步了解火神派的学术思想渊源,笔者认为它是在吸收总结了历代重视阳气的医家医著的基础上,结合四川地区的气候特点、用药习惯和对温病学流弊批判的时代背景下产生的。  相似文献   
120.
朱洪丽 《国际眼科杂志》2014,14(12):2223-2225
目的:研究增殖性糖尿病视网膜病变(proliferative diabetic retinopathy,PDR)患者血液、房水、玻璃体中血管内皮生长因子(vascular endothelial growth factor,VEGF)含量的变化,探讨VEGF与PDR的关系,为抗VEGF药物治疗的给药途径及剂量等提供理论依据。方法:采用双抗体夹心酶联免疫吸附测定法定量检测无糖尿病视网膜病变(NDR)组,单纯性糖尿病视网膜病变(BDR)组,增殖性糖尿病视网膜病变(PDR)组患者和正常对照组血浆中VEGF含量,还检测PDR患者房水、玻璃体中和正常对照组房水、玻璃体中VEGF含量,并进行综合分析。试剂盒购自美国R&D公司,其质量和灵敏度相对较高。结果:PDR组房水中VEGF含量有增高趋势,但与正常对照组比较,无统计学差异(P>0.05)。PDR患者玻璃体中VEGF含量明显增高,与正常对照组比较差异非常显著(P<0.01)。PDR组自身血浆、房水、玻璃体中VEGF含量比较有逐渐增高趋势,三者之间有显著性差异(P<0.01)。正常对照组血浆、房水、玻璃体中VEGF含量三者之间无显著性差异(P>0.05)。血浆VEGF含量在正常对照组中最高,而玻璃体中VEGF含量在PDR患者中最高。结论:PDR患者眼内尤其是玻璃体中VEGF含量大幅度增高,可能对促进DR发展恶化起了关键性的作用。在正常人,VEGF更多地存在于血浆中发挥其生物学效应。在严重DR患者中,玻璃体中异常地出现大量VEGF,推测来自缺血缺氧的视网膜,并可能有向眼前段扩散的趋势。  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