医用电子仪器中干扰与噪声的防止与抑制(下)

介绍了医用电子仪器中的干扰与噪声的产生、危害、抑制及其应用，其中有的干扰与噪声是首次提出的。     

论心电信号检测中的噪声与干扰及其消除方法

目的：认识心电信号是从体表检测到的心脏电生理信号,它对心脏疾病的诊断意义重大。方法：强调在心电信号检测过程中,很容易受到噪声（干扰）的影响,如随机噪声、工频干扰、检测系统的内部噪声等。结果：分析了心电检测中各种噪声和干扰产生的原因及消除和减小噪声（干扰）的方法。结论：为了尽可能地消除噪声（干扰）,又不使检测到的心电信号失真,这就需要改进采集电路、滤波电路,运用新的运算方法。     

关于心电监护、记录仪器使用中抗干扰措施的探讨

在观察心电示波器或记录心电图时,常见的一个主要问题,是在输出波形中表现出各种干扰,影响电子诊断的结果,严重时电子诊断仪器无法工作。外界干扰主要有人体周围的高压电源与人体通过静电耦合产生的干扰;大电流电路与人体通过磁耦合产生的干扰;噪声电流流过人体产生电压降以后引起的阻抗耦合干扰,内部噪声主要有电子诊断仪器电路的各种噪声。消除干扰和噪声的主要措施是采用正确的屏蔽,如磁屏蔽、静电屏蔽、电磁屏蔽等;合理的接地;选用低噪声元器件和差动式放大器的电路形式或采用滤波装置,将噪声和干扰加以适当地滤除,不过这样,与噪声或干扰相同频带的信号成分也会受到影响,信     

柴油机试车磨合间的噪声控制与效果评价

笔采用了墙壁波纹穿孔板吸声结构和空间悬挂式吸声体吸声，缩短了车间内的噪声混响时间，使车间内的噪声降低T30[dB（A）]；将柴油机与地基的钢性连接改为弹性连接，使90％的干扰力被隔绝，达到很好的隔振效果；采用隔声门使相邻车间不再受噪声的干扰。本次治理投资少、效果好，使噪声强度降到了国家标准以内。     

工业中脉冲与稳态噪声危害的比较

人们把各种不同频率和强度的声波无规律的紊乱组合,波形呈无规则变化的声音,是人们不需要的,起干扰作用的统称噪声。而与职业有关的,在生产环境中由于生产产生的噪声叫生产性噪声。当声音的持续时间小于0.5秒,间隔时间大于1秒,声压变化大于40     

自适应噪声抵消在抑制高频电刀对心电监护仪干扰中的应用研究

本文讨论了如何利用自适应噪声抵消去除高频电刀工作时对心电监护波形的干扰。本课题基于高频电刀干扰成分的研究，采用了滤波系统去除高频成分的干扰；利用了自适应噪声抵消系统实现对噪声的跟踪、去除。并利用MATLAB语言对抑制措施进行动态仿真，验证了抑制措施的可行性。     

校园环境噪声与学生的烦恼度

本文采用对照研究的方法,选择位于交通要道附近一小学、五年级学生116名为观察组,取远离交通要道一小学同年组76名学生为对照组。调查分析了学校环境噪声污染情况及性质;并观察比较了两校学生的烦恼度。结果表明:1.观察组教室内本底、校园内器噪声水平均高于对照组,噪声性质以低频为主,并同时存在与对照组一样的中频噪声。两校环境噪声水平均高于噪声卫生容许标准。2.观察组学生烦恼度高于对照组,并与载重汽车车流量,校园内最高噪声水平关系密切。结果提示:小学校址应远离交道干线150米以上;为减少学生自身学习活动造成较高噪声干扰,应致虑教学用房的合理配置。     

累积噪声暴露量与高血压患病率的剂量—反应关系

本文应用累积噪声暴露量的概念,在Logistic回归模型中分析了噪声暴露与纺织女工高血压患病率的关系。发现应用累积噪声暴露量可以解决噪声作业工龄与年龄高度相关在Logistic回归模型中互相干扰的问题。调整后的累积噪声暴露量的Odds Ratio为1.033,与另一模型中调整后噪声强度的Odds Ratio的1.03l非常接近,同时P值降低。表明噪声暴露与高血压病的发生之间有累积效应关系。应用累积噪声暴露量后,年龄的Odds Ratio由1.101上升为1.157,P值也由0.323降低为<0.001;父母高血压史和吃菜咸淡的Odds Ratio与应用噪声强度和噪声作业工龄的模型非常接近。用后退法比较最大似然值差值的方法证实,年龄对高血压病的危险性约为噪声的3倍、父母高血压史和吃莱咸淡分别为噪声的2倍和1.6倍。作者对年龄与工龄高度相关在职业流行病学研究中造成的困难以及应用累积噪声暴露量解决这一困难的机理进行了讨论。     

机械加工企业职业噪声暴露与高血压关系的流行病学研究

目的探讨机械加工企业职业噪声暴露与高血压的发病关系。方法对噪声作业场所进行现场噪声测定，对噪声从业人员进行现场调查。结果机械加工企业噪声从业人员高血压患病率为12．1％。随着累积噪声暴露量（CNE）的增加高血压患病率逐渐升高（趋势X^2=29．932，P〈0．01），高血压患病率与CNE之间存在明显的剂量反应关系。非条件logistic回归分析结果显示：在校正了年龄、体重指数和高血压家族史等影响因素的干扰后，CNE每增加1dB（A），噪声从业人员其高血压发病的危险增加5％（OR=1．047）。结论噪声暴露可能是高血压发病的一个危险因素，降低作业场所的噪声强度可能是减少机械加工企业噪声从业人员高血压发病的有效措施。     

监护仪心电监测故障分析与维修

本文针对心电信号采集进行实例维修探讨,如心电波形杂乱、不规则、干扰大、噪声强,心电信号消失,无ECG波形等.     

企业职工高尿酸血症与血压、血脂、血糖的相关性研究

目的探讨企业职工高尿酸血症（HUA）与血压、血脂、血糖的相关性,为企业进行健康管理提供依据。方法以中国石油长庆油田公司各下属企业为抽样单位,整群随机抽取2个单位,每个单位中所有的HUA者作为HUA组,共720人;同时在尿酸水平正常者中随机选取620人为正常组。通过Logistic回归分析HUA与年龄、性别、血压、血脂、血糖的关系。结果HUA合并高血压、高血脂、空腹m糖受损任意一项、两项、三项的比例均远高于正常组（OR值分别为：4．036,2．562,4．174）。多因素Logistic回归发现：男性、收缩压、总胆固醇、三酰甘油、低密度脂蛋白胆固醇是HUA的危险因素（OR值分别为7．736,2．309,1．721,2．761,1．411）;高密度脂蛋白胆固醇为HUA的保护因素（OR值为0．211）。结论HUA存在性别差异,且与血压、血脂密切相关。企业对职工的健康管理应充分考虑多危险因素的综合作用,全面的进行健康教育及干预。     

Continuity and change in neighborhood disadvantage and adolescent depression and anxiety

We used data from the Fragile Families and Child Wellbeing Study which includes a sample of adolescents of age 15 at the most recent wave (between 2014 and 2017) from mainly low-income urban families in the United States, to examine the association between neighborhood poverty entries and exits and adolescent depression and anxiety. In addition, we examined whether these associations differed by gender. Adolescents who consistently lived in disadvantaged neighborhoods had the highest level of depression and anxiety. Those who entered poor neighborhoods were more depressed than those who never lived in poor neighborhoods. Those who exited poor neighborhoods showed no significant difference in depression and anxiety compared to those never lived in poor neighborhoods. Furthermore, these associations applied to adolescent girls only and were not statistically significant for boys. The results suggest that neighborhood poverty has cumulative negative impacts on adolescent mental health and disproportionally affects adolescent girls. Reducing neighborhood poverty would substantially improve the health of adolescents, especially girls, which would reduce health disparities.     

Enabling positive change: Progress and setbacks in HIV and sexual and reproductive health and rights

At a point in history when the future of sexual and reproductive health including HIV looks particularly uncertain, it is helpful to recognise that many of the challenges currently faced are neither new nor insurmountable. Reflecting on past achievements and lessons learned helps us to have confidence that positive change is feasible. This paper reflects on some of the changes observed in countries like India and Mozambique and identifies a range of factors which need to coalesce to enable these developments, along with specific contextual factors. It is the combination of these influences rather than any one of them alone that brought about the change in the three instances described – fostering a positive political response to HIV in its early years in India; bringing about policy reform on abortion in Mozambique; and increasing contraceptive prevalence and age at marriage in some districts in Bihar, India. Change is always fragile and susceptible to setbacks, but change-seekers can learn in the process and gain renewed hope that progress can and often does take place if they persevere.     

癌缺氧病因及预防和治疗

目的 探讨癌及安阳林州市食管癌高发原因及癌病因预防和治疗措施.方法 对林州市食管癌等疾病现场进行调查,在进行10余年统计分析基础上,综合分析了全国156篇文献成果.结果 提出癌缺氧病因学说,使用制氧机、按摩器、饮用纯净水治疗恶性肿瘤,取得良好效果,改水能够大幅降低林州市居民食管癌发病率、死亡率.结论 癌可能是由于机体长...     

城乡居民和公务员艾滋病知识态度行为调查分析

目的了解福建沿海地区城镇、农村居民和当地公务员对艾滋病知识的掌握程度、态度及相关的行为。方法在某县城镇、农村和县公务员中,用随机整群抽样的方法,以问卷形式调查3组人群共835人。结果文化程度较低的人群,对有关艾滋病的知识了解越少,所持态度和采取行为的正确率越低,对艾滋病的担忧与恐惧程度却较高。在知识、态度和行为3个方面,由好到差的排列为公务员、城镇居民、农村居民。结论全面系统地、有针对性地开展艾滋病基本知识的健康教育,消除居民对艾滋病的恐惧心理仍是当今的重要任务。另外由于公务员对艾滋病的全面理解会对防治工作的全面开展起到极大的正反馈作用,为此在对城乡居民进行健康教育的同时,应加大对当地公务员健康教育的力度。     

儿童青少年超重肥胖评价方法及SPSS和SAS实现

超重肥胖已成为世界各国儿童青少年面临的重大公共卫生问题之一。现行的儿童青少年超重肥胖筛查标准不统一,逐条评价或自行编写程序容易出错且效率较低。本研究以中国学龄儿童青少年超重与肥胖筛查标准为例,详细介绍了国际和中国共四种评价儿童青少年超重肥胖的方法和步骤,结合具体案例详细介绍其应用方法,同时编制SPSS和SAS程序包和解...     

Work and Well-Being: Realities and Aspirations

This article summarizes research on the quality of working lifeand the effects of unemployment, and presents policy proposalsin both areas. Research findings on the quality of working lifeare discussed in terms of six major determinants: variety andchallenge; autonomy and control; resources and supervision;relations with coworkers; wages and promotion; and conditionsof work. Effects of unemployment are demonstrated in four areas— mental health, physical symptoms, physiological indicators,and economic well-being. Suggestions for future research and for social policy are madein two domains, socio-technics and reallocation of work. Thefirst, socio-technics revisited, is a proposal for interdisciplinarycollaboration in which engineering, architecture, and medicineas well as the social sciences address the problems of qualityof employment. This contrasts with the earlier research in whichthe technology of work is taken as given and the task of socialscience is adaptation to it. The proposal for the reallocationof work is based on a four-hour work module and on individualchoice, compatible with organizational requirements, on thenumber and pattern of modules to be worked. Both proposals areurged as subjects for experimental trial and revision, beforeenactment as social policy.     

Fortification and Health: Challenges and Opportunities

Fortification is the process of adding nutrients or non-nutrient bioactive components to edible products (e.g., food, food constituents, or supplements). Fortification can be used to correct or prevent widespread nutrient intake shortfalls and associated deficiencies, to balance the total nutrient profile of a diet, to restore nutrients lost in processing, or to appeal to consumers looking to supplement their diet. Food fortification could be considered as a public health strategy to enhance nutrient intakes of a population. Over the past century, fortification has been effective at reducing the risk of nutrient deficiency diseases such as beriberi, goiter, pellagra, and rickets. However, the world today is very different from when fortification emerged in the 1920s. Although early fortification programs were designed to eliminate deficiency diseases, current fortification programs are based on low dietary intakes rather than a diagnosable condition. Moving forward, we must be diligent in our approach to achieving effective and responsible fortification practices and policies, including responsible marketing of fortified products. Fortification must be applied prudently, its effects monitored diligently, and the public informed effectively about its benefits through consumer education efforts. Clear lines of authority for establishing fortification guidelines should be developed and should take into account changing population demographics, changes in the food supply, and advances in technology. This article is a summary of a symposium presented at the ASN Scientific Sessions and Annual Meeting at Experimental Biology 2014 on current issues involving fortification focusing primarily on the United States and Canada and recommendations for the development of responsible fortification practices to ensure their safety and effectiveness.     

Hygiene theory and allergy and asthma prevention

Epidemiological trends of allergic diseases and asthma in children reveal a global rise in their prevalence over the past 50 years. Their rapid rise, especially in metropolitan locales, suggests that recent changes in modern environments and/or life styles underlie these trends. One environmental/life style factor that may be contributing to this trend is called the hygiene hypothesis: that naturally occurring microbial exposures in early life may have prompted early immune maturation and prevented allergic diseases and asthma from developing. Subsequently, children raised in modern metropolitan life styles, relatively devoid of this natural microbial burden, may have under-stimulated immune systems in infancy, thereby allowing for the 'allergic march'– a pattern of pro-allergic immune development and disorders that occurs in early life. Over the past 15 years, hygiene theorising has evolved in shape and substance, in part due to a growing and strengthening burden of evidence from epidemiological, translational and basic research. What was speculation may be key clues to allergy and asthma prevention. The objectives of this article are to summarise the epidemiological trends and allergic march of childhood that may be explained by hygiene theory, to overview current hygiene theory paradigms and to exemplify the strengthening epidemiological evidence in support of the hygiene theory, using bacterial endotoxin exposure as a prototypical example.