某汽车制造企业的职业危害因素研究

[目的]分析某汽车制造企业职业危害的种类和现状,指出其主要的职业危害因素和防护重点,并提出相应的防护对策。[方法]现况调查,收集并分析某汽车制造企业的一般情况、职业危害因素历年检测结果和工人职业健康体检资料,并查阅汽车制造的职业危害研究文献。[结果]该企业主要的职业病危害因素包括噪声、电焊烟尘、锰及其化合物、苯、甲苯、二甲苯、一氧化碳和二氧化氮,噪声强度历年检测超标率最高(37.75%),苯系物和二氧化氮未超标,工人体检结果显示噪声和苯系物的危害较大。[结论]汽车制造业的主要职业危害为噪声、粉尘和毒物。该企业今后应加强管理,加大对噪声和电焊烟尘的有效防护,并重视毒物长期低浓度接触对工人健康的影响。     

二连浩特口岸入境交通工具消毒效果评估

〔目的〕了解全自动卫生处理设备的消毒效果,为评估该设备的应用效果提供科学依据。〔方法〕对消毒处理前和处理后的样品分别进行增菌培养,菌落计数采样方法按照《微生物检验抽样原则》(GB/T47891-2003)进行,实验室检测菌落总数参照《菌落总数标准》(GB/T4789.2-2003)方法进行。〔结果〕经检测采用自动消毒喷洒装置消毒前与消毒后杀菌效果存在明显差异。〔结论〕经检测该设备性能可靠、高效、实时性好,符合卫生处理标准,可完成消杀灭任务,适用于进出境货物和交通工具的卫生处理。     

Prenatal ethanol exposure alters sensitivity to the effects of corticotropin-releasing factor (CRF) on behavior in the elevated plus-maze

Animals prenatally exposed to ethanol (E) exhibit behavioral alterations in a wide variety of stressful or challenging tasks. The hypothalamic peptide corticotropin-releasing factor (CRF) is known to play a crucial role in integrating an organism's behavioral responses to environmental stressors or challenges. Previous research indicates that E animals exhibit increased hypothalamic-pituitary-adrenal (HPA) reactivity, including increased hypothalamic CRF expression under both basal and stress conditions. However, the possible role of CRF in mediating the behavioral changes observed in E animals remains to be determined. The current study investigated the hypothesis that E animals may be differentially sensitive to the effects of CRF on behavior in the elevated plus-maze, a task widely used to assess anxiety-like behavior in rodents. Sprague-Dawley offspring from prenatal E, pair-fed (PF), and ad lib-fed control (C) groups were tested at 60-90 days of age. Thirty minutes prior to a 5 min test on the elevated plus-maze, animals received an icv infusion of vehicle (VEH) or CRF (males: 0.75 microg or 1.5 microg ; females: 1.0 microg or 2.0 microg ). Under VEH conditions, E males showed greater activity (more total arm entries) than PF and C males and both E males and E and PF females showed less anxiety-like behavior (more open arm entries) than their PF and/or C counterparts. As expected, CRF treatment resulted in fewer open arm, closed arm and total arm entries, and total rears in both males and females in all prenatal groups, and increased time in the closed arms in males compared to that in their VEH-treated counterparts. Importantly, the effects of CRF were most pronounced in E animals. That is, when normalized for prenatal group differences following VEH treatment, CRF-treated E males showed fewer total arm entries and total rears than PF and C males, and CRF-treated E and PF females showed fewer open arm entries than C females. These results support and extend previous findings demonstrating that E animals show altered behavior in aversive or stressful situations. While some effects of CRF in females may be mediated partially by nutritional effects of ethanol, the data overall suggest that the behavioral alterations observed in E animals may be due, at least in part, to increased sensitivity to CRF.     

Simulated vehicle exhaust exposure induces sex-dependent behavioral deficits in rats

Chronic exposure to vehicle exhaust emissions are known to cause several adverse health effects. In this study, we examined the impact of several parameters of behavioral, cardiovascular and biochemical functions upon exposure of pro-oxidants CO₂, NO₂ and CO (simulated vehicle exhaust exposure: SVEE) in male and female rats. Adult rats were subjected to SVEE or ambient air in whole body chambers (5 h/day, 2 weeks). Male, but not female, rats developed memory deficits, and exhibited anxiety- and depression-like behavior, accompanied with significantly high levels of serum corticosterone, oxidative stress, and inflammatory markers (CRP and TNFα), associated with lower levels of total antioxidant capacity, glutathione, glyoxalase and superoxide dismutase (SOD) activities. Brain region-specific downregulation of Cu/Zn SOD, Mn SOD, GSR, PKCα, ERK_1/2, CaMKIV, CREB, BDNF and NMDAR subunit protein expression were also observed in male, but not female, rats. Blood pressure, heart rate and eGFR were not negatively impacted by SVEE. Our results suggest that SVEE, through its pro-oxidant content, induces oxido-inflammation in susceptible brain regions in a sex-dependent manner.     

Simulating self-motion

In general, vehicle motions far exceed the mechanical constraints of an earth-fixed simulator base. Inertial motions can, therefore, only be simulated in partial agreement with those of the actual vehicle. As a consequence, physical mismatches between inertial and environmental motion are inevitable. Here, the concept of a subjective reference frame is introduced, relative to which perceived self-motion is defined. This frame must be released from the earth-fixed frame to evoke simulated self-motion. In addition, self-motion and environmental motion need to be perceived reciprocal, in order to evoke a stationary perceived environment. Due to the only limited accuracy of human self-motion perception, however, perceived self-motion and perceived environmental motion need not to be exactly reciprocal. The extent to which self-motion and environmental motion may differ can be expressed by a just noticeable difference. This just noticeable difference denotes the threshold at which the environment is perceived to move. In this article, a self-motion perception model is outlined in which perceived environmental motion and perceived self-motion are separated. The perception model and the just noticeable differences can then be applied to determine the inertial stimulation that is needed to evoke perceived self-motion, in which the environment is perceived stationary throughout simulation.     

Biomechanics and physiology in active manual wheelchair propulsion

Manual wheelchair propulsion in daily life and sports is increasingly being studied. Initially, an engineering and physiological perspective was taken. More recently a concomitant biomechanics interest is seen. Themes of biomechanical and physiological studies today are performance enhancing aspects of wheelchair use and the ergonomics of wheelchair design. Apart from the propulsion technique the focus of biomechanics research of manual wheelchair propulsion is mainly towards injury mechanisms, especially phenomena of overuse to the upper extremity. Obviously, the vehicle mechanics of wheelchairs must be included within this biological framework.

Scientific research is progressing, but is still hampered by methodological limitations, such as the heterogeneity and small numbers of the population at study as well as the inconsistency of employed technologies and methodologies. There is a need for consensus regarding methodology and research strategy, and a strong need for collaboration to improve the homogeneity and size of subject groups and thus the power of the experimental results. Thus a sufficiently strong knowledge database will emerge, leading to an evidence-base of performance enhancing factors and the understanding of the risks of wheelchair sports and long-term wheelchair use.

In the light of the current biomechanical and physiological knowledge of manual wheelchair propulsion there seems to be a need for the stimulation of other than hand rim propelled manual wheelchairs.     

车辆与道路因素对交通伤害发生的影响

[目的]探讨车辆与道路因素在道路交通伤害中发挥的作用,提出相应防范措施。[方法]比较分析本地50232起道路交通伤害事件中车辆及道路因素的影响。[结果]车和路的因素分别占了2%、24%左右,机械故障、小型车、高等级道路、平直沥青路面等因素所占比重列第一。[结论]要重视车的设计、制造、使用等过程中安全性研究;加快道路建设、重视路的安全设计和交通设施的完善程度是减少RTI的重要条件。     

Incidence and strategies for preventing sustained hypothermia of crash victims during prolonged vehicle extrication

Background

Vehicle extrication of crash victims is a highly-demanding challenge, due to the frequently life-threatening injuries of entrapped occupants. In this phase, crash victims are often exposed to the outdoor-temperature, with the risk of sustained hypothermia. Hypothermia can significantly raise the morbidity and mortality rates of crash victims. Therefore, we have correlated the incidence of severe car accidents with entrapped patients, the outdoor conditions, and expenditure of time for extrication. Furthermore, different warming strategies have been evaluated regarding their integrability within the rescue procedure.

丁型肝炎病毒载体携带核酶在小鼠体内抑制乙型肝炎病毒复制

目的:研究用丁型肝炎病毒(HDV)作为载体携带乙型肝炎病毒(HBV)特异性的锤头状核酶所构建的重组体,在细胞体系及转染动物模型中对HBV基因表达和复制的影响.方法:将HDV-核酶重组体和HBV的共表达质粒转染Huh-7细胞以分析HDV-核酶重组体对HBV基因表达的影响;用小鼠尾静脉快速注射法将共表达质粒转染到小鼠体内,检测重组体在动物体内对HBV基因表达和复制的抑制作用.结果:转染细胞中,重组体对HBsAg的抑制与HDV重组位点和核酶靶位都有关;水压法注射的质粒在小鼠肝内得到表达,与对照相比重组HDV-核酶可有效抑制在肝和血清中HBV的基因表达以及复制,与细胞中的结果一致.结论:此项体内实验为进一步构建治疗性重组HDV病毒,发现靶向性抗病毒基因治疗手段奠定基础.     

氢氧化钙封药载体的研究进展

氢氧化钙是近年临床上应用广泛的根管消毒剂,因其封药载体的不同,所产生的药效也存在差异.常用的氢氧化钙封药载体分水溶性、黏性和油性,探讨不同载体对氢氧化钙抗菌性能的影响是近年来的研究热点.本文就氢氧化钙封药载体的研究现状进行综述.