广东高本底和对照地区居民肺组织中钍同位素含量的测定

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。     

我国阳江高本底地区居民吸入氡、氧及其子体的年有效剂量当量

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。     

Dental caries prevalence and treatment needs of 5- to 12-year-old children in relation to area-based income and immigrant background in Greece

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.     

磁刺激用线圈设计

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。     

Differential effects of background noise of various intensities on neuronal activation associated with arousal and stress response in a maze task

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.     

The lack of target specificity of small molecule anticancer kinase inhibitors is correlated with their ability to damage myocytes in vitro

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.     

VEGF在PDR中的表达及作用的研究

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。     

湘葛一号总黄酮与气候因子的灰色关联度分析

目的运用灰色关联法筛选出影响湘葛一号总黄酮含量的气候主导因子。方法利用紫外分光光度法测定不同采收期湘葛一号不同部位总黄酮含量,采用灰色关联法对其与气候因子的相关性进行分析。结果湘葛一号不同部位、不同采收期总黄酮含量有较大区别。月平均气温、月极端最高气温、月极端最低气温、月平均相对湿度、月降水量、日照时数6个气候因子与湘葛一号根、茎、叶中总黄酮含量关系密切,灰色关联系数均达到0．50以上。其中月平均相对湿度、月极端最高气温和日照时数与根、茎、叶的灰色关联系数达到0．75以上。结论月平均相对湿度、月极端最高气温和日照时数是影响湘葛一号不同部位总黄酮含量的主导因素,实验结果可为湘葛一号的规范化种植提供科学依据。     

Anticipatory smooth-pursuit eye movements in man and monkey

A fundamental problem in the generation of goal-directed behaviour is caused by the inevitable latency of biological sensory systems. Behaviour which is fully synchronised with the triggering sensory event can only be executed if the occurrence of this event can be predicted based on prior information. Smooth-pursuit eye movements are a classical and well-established example of goal-directed behaviour. The execution of these eye movements is thought to be very closely linked to the processing of visual motion signals. Here, we show that healthy human subjects as well as trained rhesus monkeys are able to initiate smooth-pursuit eye movements in anticipation of a moving target. These anticipatory pursuit eye movements are scaled to the velocity of the expected target. Furthermore, we can exclude the possibility that anticipatory pursuit is simply an after-pursuit of the previous trial. Visually-guided pursuit is only marginally affected by the presence of a structured background. However, the presence of a structured background severely impedes the ability to perform anticipatory pursuit. More generally, our data provide additional evidence that the cognitive oculomotor repertoires of human and monkeys are similar, at least with respect of smooth-pursuit in the prediction of an appearing target.     

浅论日汉词语翻译的文化背景

文化背景包括地理环境、社会历史、宗教信仰与价值观念等。中日文化背景不同,导致一些带有文化背景的词语翻译困难。在翻译时要尊重词语的文化背景和原文语境,力求反映词语的原意。