污水微生物气溶胶污染空气的指示菌选择

为了选择污水微生物气溶胶的现场调查指示菌,本文对曝气池、滴滤池及氧化塘三种类型污水处理厂附近空气中的细菌总数、真菌总数及肠道G(—)杆菌作了定量调查。结果表明以大肠菌群或肠道G(—)菌作为指示菌是适用的。     

健康和哮喘志愿者吸入不同粒径硫酸雾对呼吸反应的影响

为研究酸性雾粒大小对呼吸生理反应的影响,作者使哮喘和健康志愿者分别吸人体积中值直径为20、10和1μm、浓度为2000μg/m~3的硫酸气溶胶,并以相同方法吸去离子水气溶胶作对照。受试者每次接触上述气溶胶1小时,中间包括3次10分钟的运动和肺功能测定,通气率为40～45L/min。按随机顺序每隔7天试验一次。吸入室气温为10℃、吸入直径为20和10μm气雾时,相对湿度为100%;吸入直径为     

厦门鼓浪屿港子后气溶胶粒子的时空分布

气溶胶是指固态、液态的微粒在空气中所形成的悬浮体系。作为水滴和尘埃是太阳辐射的吸收体和散射作,并参与各种化学和生物学循环。微生物悬浮于空气中可形成各种各样的微生物气溶胶,成分十分复杂,与人类健康关系十分密切。小于5μm的气溶胶可以自由地被吸入和沉着在人体的呼吸道内,造成对人体有益或有害的影响。为弄清其好坏,气溶胶质粒浓度的变化,首先要测定空气中气溶胶质粒浓度,以评价空气对人类健康影响。我们在厦门鼓浪屿港子后陆军疗养院内定点定时测定空气中微粒的本底数值和它的变化,现将结果报告如下。     

气溶胶颗粒在人体呼吸道内沉积分布的数值模拟研究

目的 通过基于健康志愿者呼吸道CT影像数据重建的数值仿真模型，比较不同粒径颗粒物在正常人呼吸道内的沉积分数差异，探讨气溶胶颗粒在呼吸道内的沉积规律。方法 采集2021年1—12月50名健康志愿者的呼吸道CT影像数据，重建呼吸道数值仿真模型，模拟吸气过程中悬浮颗粒物在呼吸道内的运动过程，观察气流流场的分布特征，计算3种不同粒径大小的颗粒物在呼吸道内沉积分数。采用单因素方差分析检验对比3种粒径颗粒物沉积分数之间的差异。结果 粒径1μm的颗粒物在呼吸道内的沉积分数为0.201±0.014，粒径为2.5μm的沉积分数为0.387±0.014，粒径为10μm的沉积分数为0.732±0.016,3者差异有统计学意义（P<0.05）。10μm的颗粒物沉积分数最大，1μm的颗粒物沉积分数最小。结论 在数值仿真模型研究中气溶胶颗粒物在呼吸道内的沉积分数随着粒径增大而增大，为吸入性药物、雾化吸入用医疗装备的研究和设计提供参考。     

碳粒和粘膜纤毛的运送

八名肺部健康的观察对象定量吸入用放射性同位素锝(~(99)Tc)标记的聚四氟乙烯颗粒气溶胶。颗粒大小为6微米,气体动力直径为8～9微米。吸入后二小时内连续在胸部体表测定肺内总放射性。每人受试两次,一次在吸入上述气溶胶后立即吸入直径为11微米左右的碳粒,另一次不吸。试验期间皆无咳嗽。以吸入气溶胶60分钟后测得的放射性滞留百分比相比     

小颗粒微生物气溶胶的采样方法研究

我们用B271噬菌体做小颗粒微生物气溶胶的试验模型,比较了Anderson、Jwl-1、MF-45和AGI-10四种空气微生物采样器的捕获效果。气溶胶粒子的CMD为1.25～3.75μm,综合看,以Anderson采样器最佳。     

医院内耐甲氧西林金黄色葡萄球菌气溶胶的浓度及其粒径分布特征

目的探讨医院中金黄色葡萄球菌及其中耐甲氧西林金黄色葡萄球菌(MRSA)气溶胶的浓度及其粒径分布特征,为医院有效防治气源感染提供基础资料。方法用FA-1型六级筛孔撞击式空气微生物采样器采集3所医院的大厅、ICU及普通外科病房的室内空气。同时采集医院外上风空气作为对照。分析金黄色葡萄球菌及MRSA气溶胶在不同采样点的浓度及其气溶胶粒径分布。结果金黄色葡萄球菌气溶胶总浓度及可吸入浓度均在大厅中最高,分别为166.08 cfu/m3及102.47 cfu/m3,其他依次为病房、ICU及室外;MRSA气溶胶总浓度与可吸入浓度均在ICU中最高,分别为63.60 cfu/m3和28.27 cfu/m3,其次为大厅、普通外科病房及室外。金黄色葡萄球菌及MRSA气溶胶浓度室内外比值均超过1.0。总体上医院内金黄色葡萄球菌可吸入气溶胶颗粒(分布在采样器第三~六级,粒子直径≤4.7μm)占54.80%;医院内MRSA可吸入气溶胶颗粒占54.95%。结论医院空气中存在气载金黄色葡萄球菌及MRSA污染,50%以上的气溶胶粒子≤4.7μm,构成下呼吸道感染威胁,应加强对医院空气中致病菌的监测及消毒工作。     

矽肺发病的当代概念和设想

矽肺是一种因吸入各种形式的结晶型二氧化硅(SiO_2)所引起的慢性炎症性和纤维性的肺部疾病。本文主要讨论有细胞免疫或体液免疫反应参与的炎症和纤维化活动的交替作用,从而导致矽肺的发生这样一个假想的发病机理。粉尘的沉积与清除及矽肺的病理学特点吸入的粉尘在呼吸道不同部位的沉积取决于颗粒的大小、形状、质量、空气动力学特性和其他物理性质。一般0.5～5μm的粉尘可到达呼吸道下部,并沉积在小气道或肺泡,而<0.5μm的粉尘可悬浮于呼出气流中或沉积于肺泡内。沉积于气道纤毛上皮的粘膜荚     

污水微生物气溶胶对大气污染的研究

本文对曝气池、滴滤池和氧化塘三种常用的污水生物处理厂周围空气中微生物气溶胶产生、扩散、波及范围等进行了调查,提出了空气中微生物革兰氏阴性杆菌来源于污水的依据:大肠杆菌群落形成单位的数量随着离污水池距离增加而减少;不排放污水的对照池周围空气未发现革兰氏阴性杆菌。三种处理方法形成的微生物气溶胶作用不同,滴滤池的喷雾及曝气池的搅拌充气均产生大量污水气溶胶,在氧化塘平静的水面上即使产生气溶胶也是轻微的。     

大型补给船舱室细菌气溶胶浓度及细菌菌谱特征调查

目的调查某大型补给船船舱内细菌气溶胶的浓度及构成,了解与细菌气溶胶影响相关的健康状况。方法采用安德森CA6型及CA2型撞击式空气采样仪,对舱室细菌气溶胶进行定量富集和粒径大小的分析,通过细菌学分析方法对富集的细菌进行种属鉴定,对艇员的健康状况进行量表调查。结果 (1)调查区域细菌气溶胶浓度为102~103CFU/m3。(2)60.6%~73.9%的舱室细菌气溶胶颗粒粒径大小为0.65~4.7μm。(3)空气中的细菌分布在15个菌属,由31个菌种构成。革兰阳性细菌占85.1%,其中革兰阳性球菌最多(41.8%),其余为芽孢杆菌属(24.3%)和无芽孢革兰阳性杆菌(19.0%)。革兰阴性杆菌占14.9%,其中肠杆菌科细菌5.4%,非发酵菌9.5%。结论该补给船舱室均处于相对较低的空气微生物污染水平,将粒径和条件致病菌一并作为评价因素,仍存在健康安全的隐患。     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

Self-reported health problems among Swedish miners one year after unemployment

Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).     

Excès de cas humains et animaux de tularémie en France au cours de l’hiver 2007–2008 : émergence ou phénomène isolé ?

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.     

Occupational health hazards in mining: an overview

This review article outlines the physical, chemical, biological, ergonomic and psychosocial occupational health hazards of mining and associated metallurgical processes. Mining remains an important industrial sector in many parts of the world and although substantial progress has been made in the control of occupational health hazards, there remains room for further risk reduction. This applies particularly to traumatic injury hazards, ergonomic hazards and noise. Vigilance is also required to ensure exposures to coal dust and crystalline silica remain effectively controlled.     

Manufacture and use of nanomaterials: current status in the UK and global trends

This paper provides an overview of the production and use of nanomaterials (NMs), particularly in the UK. Currently, relatively few companies in the UK are identifiable as NM manufacturers, the main emphasis being the bulk markets in metals and metal oxides, and some niche markets such as carbon nanotubes and quantum dots. NM manufacturing in the UK does not reflect the global emphasis on fullerenes, nanotubes and fibres. Some assumptions have been made about the types of NM that are likely to be imported into the UK, which currently include fullerenes, modified fullerenes and other carbon-based NMs including nanotubes. Many university departments, spin-offs and private companies have developed processes for the manufacture of NMs but may only be producing small quantities for research and development (R&D) purposes. However, some have the potential to scale up to produce large quantities. The nanotechnology industry in the UK has strong R&D backup from universities and related institutions. This review has covered R&D trends at such institutions, and appropriate information has been added to a searchable database. While several companies are including NMs in their products, only a few (e.g. manufacturers of paints, coatings, cosmetics, catalysts, polymer composites) are using nanoparticles (NPs) in any significant quantities. However, this situation is likely to change rapidly. There is a need to collect more information about exposure to NPs in both manufacturing and user scenarios. As the market grows, and as manufacturers switch from the micro- to the nanoscale, the potential for exposure will increase. More research is required to quantify any risks to workers and consumers.     

深圳公立医院管理体制改革制度设计

深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.     

Effects of nitrogen dioxide on red blood cells of rats: Changes in components of red cell membranes during in vivo exposure to NO2

Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO₂) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO₂. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO₂ at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO₂ gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO₂ also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO₂.     

Investigating clusters in the workplace and beyond

Clusters of disease are common and occur in the workplace and in the general community. They often arouse considerable concern among the population. Investigations have sometimes lead to exciting new knowledge, but in general the investigation of clusters is difficult and often unrewarding, especially for community clusters. In the workplace, investigations are more likely to find associations and even new causes, but still many clusters remain enigmatic. Despite this, there are many reasons for investigating clusters, including allaying community concern and identifying uncontrolled exposures. A structure for investigating clusters in the workplace is suggested.