同位镀锑膜修饰电极方波溶出伏安法同时测定痕量锡、镉

目的:建立同位镀锑膜电极测定痕量锡和镉的新方法。方法:在玻碳电极上,采用同位镀锑的方法富集被测离子并形成锑膜,利用方波脉冲伏安法使富集的Sn、Cd重新溶出,根据溶出峰电流,实现对痕量Sn2+、Cd2+的同时测定。在十六烷基三甲基溴化胺(CTAB)存在的条件下,溶出峰形良好。讨论了底液的pH值、CTAB浓度、富集时间、富集电位和不同的扫描速率对金属离子溶出峰的影响。结果:在优化实验条件下,Sn2+和Cd2+的线性范围分别为5μg/L～180μg/L和10μg/L～170μg/L,最低检出限分别为0.46μg/L和2μg/L。利用本方法测定了茶叶中Sn2+的含量,结果令人满意。结论:锑膜电极可成为又一种新的环保型膜电极用于重金属离子的测定。     

十六烷基三甲基溴化铵存在下锑膜修饰玻碳电极差分脉冲溶出伏安法测定尿中痕量铅、镉

目的考察并优化同位镀锑膜修饰玻碳电极同时测定Pb2+、Cd2+的方法。方法采用十六烷基三甲基溴化铵(CTAB)作为增敏剂,以锑膜修饰玻碳电极作为工作电极差分脉冲溶出伏安法测定尿中痕量Pb2+、Cd2+。结果 Pb2+、Cd2+在锑膜电极上可得到灵敏的溶出峰,溶出电位分别为-0.48 V和-0.73 V。当富集时间为180 s时,Pb2+、Cd2+的线性范围为0~100μg/L(r≥0.991),检出限分别为0.47μg/L和0.78μg/L,Pb2+、Cd2+的加标回收率分别为92.0%~104.3%和94.0%~102.6%,相对标准偏差(RSD)分别为4.1%~5.0%和2.8%~6.1%。利用该方法测定了尿样中Pb的含量,结果令人满意。结论该方法灵敏度高,精密度、准确性好,锑膜修饰玻碳电极可作为一种新的环保膜电极代替汞膜电极用于尿样中Pb含量的检测。     

原子荧光光谱法测定尿锑的两种预处理方法研究

目的探讨氢化物发生-原子荧光光谱法测定尿中锑的预处理方法,比较两种预处理方法的可靠性和一致性。方法两种预处理方法为分别将尿样经强酸消化、强氧化剂组合消化,再分别用硫脲-抗坏血酸溶液、10g/L的L-半胱氨酸溶液预还原,然后用原子荧光光谱法测定尿样中的锑。结果方法一测定尿中锑在0.0~10.0μg/L之间线性关系较好,相关系数为0.999 4~0.999 9,最低检出限为0.06μg/L,相对标准偏差为1.9%~2.8%,平均加标回收率为98.5%~103.2%。方法二测定尿中锑在0.0~10.0μg/L之间线性关系较好,相关系数为0.999 3~0.999 7,最低检出限为0.06μg/L,相对标准偏差为1.6%~3.4%,平均加标回收率为97.3%~101.3%。在实际应用中两种方法对样品检测结果的差异无显著性意义。结论两种方法均适用于职业健康体检和职业性中毒尿中锑的检测。     

氢化物原子荧光法同时测定工作场所空气中的砷和锑

为了建立氢化物发生-原子荧光光谱法同时测定空气样品中砷和锑,选用过氧化氢和硝酸的混合液作为消解试剂,用控温消解仪消解。结果显示,氢化物发生的条件:浓度为5%的盐酸溶液为反应介质,硫脲及抗坏血酸浓度分别为10 g/L,硼氢化钾为15 g/L,NaOH溶液浓度为20 g/L。该方法在最佳测定条件下,砷的线性范围为0~30μg/L,锑的线性范围为0~30μg/L;检出限砷和锑分别为0.7μg/L和0.4μg/L;样品的加标回收率砷为94%~106%,锑为95%~104%;方法精密度砷为0.8%~2.2%,锑为1.2%~2.7%。提示,该方法灵敏度高,取样量少,线性范围宽,准确可靠,操作简单快速,分析过程中对环境污染少,是一种较好的分析方法。     

原子荧光法测透析用水中砷硒锑汞

目的:建立透析用水中砷、硒、锑、汞四种微量元素的原子荧光分析法。方法:水中砷和锑加还原剂后同时测定;硒经硝酸高氯酸氧化后,再经盐酸还原后测定;汞直接加硝酸使酸度为5%后测定。结果:汞的检出限为0.024μg/L;硒的检出限为0.044μg/L;砷的检出限为0.011μg/L;锑的检出限为0.015μg/L。结论:本法用来测定透析用水中极其微量的砷、硒、锑、汞简便快速,且在双道原子荧光法仪中可同时进行砷和锑的检测。     

氢化物原子荧光光谱法测定矿区环境 天然水中的痕量锑

目的:建立一种原子荧光光谱法测定水中锑。方法:采用硫脲、抗坏血酸处理水样品,优化测定条件,氢化物发生—原子荧光光谱法测定水样品中锑。结果:锑的检出限、相对标准偏差、回收率分别为0.037μg/L,4.7%,96.2%~102.81%。结论:方法灵敏度高,准确、快捷,测定水样品中锑省时、省力。     

同时测定水中砷和锑的氢化物发生-原子荧光光谱法

目的建立双道原子荧光光度计同时测定饮用水中砷和锑的方法,以提高工作效率。方法选择最佳的仪器条件,进行样品处理方法及酸度、硼氢化钾浓度、检出限、线性范围、精密度、加标回收率等研究。结果该方法线性关系:砷为0～80μg/L,锑为0～40μg/L。检出限:砷为0.087μg/L,锑为0.19μg/L。相对标准偏差:砷为1.93%～2.55%;锑为1.97%～3.02%。平均加标回收率:砷为95.7%;锑为96.5%。结论该方法操作简便,灵敏度高,快速,便于推广,适用于水中砷和锑的同时测定。     

原子荧光光谱法测定血液中砷和锑

本文建立了职业接触人群血液中痕量砷、锑同时测定的原子荧光光谱法。该方法实现了在线一次进样的情况下对样品中的痕量砷、锑同时进行测定。通过实验优化了仪器条件、酸度及氢化反应的条件,同时对一些可能会对荧光值产生干扰的元素进行了试验,并考察了分析条件。在最佳测定条件下,砷的线性范围为0～50μg/L,锑的线性范围为0～50μg/L;检出线砷和锑分别为0.67μg/L和0.40μg/L;样品的砷加标回收率为73.1%～95.2%,锑为75.1%～90.7%。方法精密度砷为0.79%～2.22%,锑为1.16%～2.69%。该方法灵敏度高,取样量少,线性范围宽,准确可靠,操作简单快速,分析过程中对环境污染少,是一种较好的分析方法 。     

微波消解同时测定农产品中铅、镉、汞

目的:建立一种适合同时测定农产品中铅,汞,镉的样品前处理方法。方法:采用微波消解方法处理样品,样品消化液经赶酸后定容,分别用来测定汞和铅、镉。结果:测定铅,镉,汞方法的线性范围分别为:0.0μg/L～20μg/L,0.0μg/L～2μg/L,0.0μg/L～5μg/L;相关系数分别为:0.9979,0.9978,0.9988;回收率分别为:95.8%～103%,95.1%～104%,98.4%～110.6%;方法的检测限分别为0.012μg/L,0.009μg/L,0.0027μg/L。结论:该方法精密度好,准确度高,快速简单,能够很好地满足农产品中铅,汞,镉含量的测定要求。     

原子荧光光谱法同时测定感冒冲剂中的砷和锑

介绍了一种氢化物发生—双道原子荧光光谱法同时测定感冒冲剂中砷和锑的方法。进行了实验条件的最佳化选择 ,探讨了共存离子对砷和锑测定的干扰和消除方法。在最佳工作条件下 ,砷和锑的检出限分别为 0 0 90 3μg/L和 0 0 5 78μg/L ,相对标准偏差分别为 2 0 1%和 1 39% ,砷和锑的样品测定回收率分别为89 2 %～ 97 8%和 90 8%～ 10 1 4 %。     

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.     

The occurrence of antimicrobial substances in toilet,sink and shower drainpipes of clinical units: A neglected source of antibiotic residues

Antibiotics represent one of the most important drug groups used in the management of bacterial infections in humans and animals. Due to the increasing problem of antibiotic resistance, assurance of the antibacterial effectiveness of these substances has moved into the focus of public health. The reduction in antibiotic residues in wastewater and the environment may play a decisive role in the development of increasing rates of antibiotic resistance. The present study examines the wastewater of 31 patient rooms of various German clinics for possible residues of antibiotics, as well as the wastewater of five private households as a reference.To the best of our knowledge, this study shows for the first time that in hospitals with high antibiotic consumption rates, residues of these drugs can be regularly detected in toilets, sink siphons and shower drains at concentrations ranging from 0.02?μg·L^?1 to a maximum of 79?mg·L^?1. After complete flushing of the wastewater siphons, antibiotics are no longer detectable, but after temporal stagnation, the concentration of the active substances in the water phases of respective siphons increases again, suggesting that antibiotics persist through the washing process in biofilms. This study demonstrates that clinical wastewater systems offer further possibilities for the optimization of antibiotic resistance surveillance.     

The human drama of genetics: 'hard' and 'soft' media representations of inherited breast cancer

This paper examines media coverage of 'breast cancer genetics', and explores its implications for public understanding. We present a content analysis of coverage in British newspapers and look at a variety of popular forms, including women's magazines, television soap opera and radio drama. Genetic/inherited risk receives a great deal of coverage across a wide range of media formats and outlets. Much of this attention has focused on individuals from 'high risk families' and dilemmas around prophylactic mastectomies. Through examining media coverage, combined with interviews with media personnel and their sources, we show why this story proved so attractive to the media and highlight the different production values which influence coverage. Finally, we introduce preliminary findings from focus group discussions to demonstrate how such 'human interest' framing has engaged audience attention and influenced public understandings. The paper concludes by highlighting the implications for analysing, predicting, and engaging with, media representations of science.     

Fatigue and health in a seafaring population

Background Occupational fatigue is relatively common withinthe general population and has been linked to reduced performance,injury and longer term ill-health. Despite growing acknowledgementof this problem in the maritime sector, little research hasbeen conducted into the risk factors, prevalence and consequencesof seafarers' fatigue. Aims To examine the prevalence of fatigue among seafarers, identifypotential risk factors and assess possible links with poor performanceand ill-health. Methods Cross-sectional questionnaire survey of seafarers workingin the offshore oil support, short-sea and deep-sea shippingindustries. A number of tools were used including the fatiguesubscale of the profile of fatigue-related symptoms, the CognitiveFailures Questionnaire, the General Health Questionnaire andthe SF36 General Health scale. Results In all, 1855 questionnaires were completed giving anoverall response rate of 20%. Fatigue symptoms were associatedwith a range of occupational and environmental factors, manyunique to seafaring. Reporting a greater number of risk factorswas associated with greater fatigue [e.g. OR = 2.53 (1.90–3.35)for those with three or four risk factors and OR = 9.54 (6.95–13.09)for those with five or more risk factors]. There was also astrong link between fatigue and poorer cognitive and healthoutcomes, with fatigue the most important of a number of riskfactors, accounting for 10–14% of the variance. Conclusions Seafarers' fatigue could impact on safety withinthe industry and may be linked to longer term individual ill-health.It can only be addressed by considering how multiple factorscombine to contribute to fatigue.     

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.     

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.     

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.