直接稀释-石墨炉原子吸收法测定全血中的铅

目的:建立直接稀释-石墨炉原子吸收光谱法测定全血中铅的方法.方法:用混合基体改进剂[0.2g/L PdCl2 0.1 g/L Tritonx-100 1.0 ml/L HNO3]直接稀释血样,Zeeman石墨炉原子吸收光谱仪,全自动进样方法进行测定.结果:方法线性范围为0～40μg/L,相关系数为0.9998,RSD为3.3%～10%,回收率为90%～103%,方法的检出限为1.2μg/L.结论:该法准确度、精密度良好,样品不需消化,污染小,是一种简便、快速、可行的测定全血中铅的方法.     

石墨炉原子吸收法直接测定血铅及其不确定度分析

[目的]建立一种石墨炉原子吸收光谱法直接测定血铅的方法,并对其不确定度进行分析.[方法]血样用0.15%(V/V)硝酸溶液稀释后,直接用石墨炉原子吸收法测定.并依据JJF1059-1999,对各不确定度分量进行分析评定.[结果]石墨炉原子吸收法测定血铅的灰化温度为500℃.标准曲线的线性范围为0-100 μg/L,方法的检出限为3.2μg/L,测定样品的相对标准偏差在2.1%～4.9%之间,冻干牛血标准物质GBW09139e的测定值与标准值的相对误差为1.7%.对于血铅含量为153.6 μg/L的冻干牛血质控样,其扩展不确定度为6.2 μg/L(k=2).[结论]该方法操作简便、快速、准确,符合生物材料中有害物质测定规范要求,可用于血铅的测定.     

响应面法优化石墨炉原子吸收光谱法直接测定小鼠全血铅

[目的]探讨响应面法优化石墨炉原子吸收光谱法直接测定全血中铅。[方法]以0．5％Triton X-100溶液做血液稀释剂,0．05％氧化钯＋0．1％硝酸混合溶液为基体改进剂,直接进样测定。在单因素的基础上,采用中心组合设计和响应面分析法优化灰化温度、原子化温度和基体改进剂用量等因素,并在优化条件下测定小鼠全血铅结果。[结果]响应面法优化石墨炉原子吸收谱法直接测定小鼠全血铅的最优测定条件为灰化温度760．85％,原子化温度2486．80％,基体改进剂加入量0．97mL。在已优化的条件下测定铅的检出限为0．204μg／L,相对标准差（n=6）为1．76％。染毒小鼠的全血铅含量为82．1μg/L,加标回收率为96．5％-98．4％。[结论]响应面法优化石墨炉原子吸收光谱法不需消化和离心,直接进样,简便快速和准确,适用于染毒小鼠全血铅的测定。     

全血中铅的石墨炉原子吸收光谱测定法

目的探讨用石墨炉原子吸收光谱法测定全血中铅的方法。方法用混合基体改进剂[5.0g/LNH4H2PO4 1.0g/LTritonx-100 2.0ml/LHNO3]稀释样品,采用Zeeman石墨炉原子吸收光谱仪,全自动进样方法进行测定。结果方法的线性范围为0～40μg/L,相关系数为0.9982,RSD为5.5%～12.2%,回收率为90%～106%,方法的检出限为1.1μg/L。结论此方法具有结果准确可靠、方法简便快速、样品不需消化、污染小等优点,可适用于血铅的测定。     

全血中铅的石墨炉原子吸收法测定研究

目的采用石墨炉原子吸收法测定全血中的铅。方法全血样品经10%硝酸酸化,以Zeeman效应扣背景,用石墨炉原子吸收法直接测定。结果标准曲线在0～230μg/L范围内线性良好,线性方程为Y=0.00069X 0.00281,相关系数r=0.9993,方法的检出极限为0.0031μg/L,相对标准偏差(RSD)<5%,质控样品检测结果满意。结论该方法快速、简便,准确度高,重复性好,符合卫生部《血铅临床检验技术规范》要求。     

Z-5000原子吸收光谱法检测血铅的方法学研究

[目的]建立一种简便、快速、准确的血铅测定方法;检测农村儿童血铅水平。[方法]取全血0.5ml,用基体改进剂NH4H2PO4、TritonX-100和HNO3进行稀释;用Z-5000石墨炉原子吸收光谱仪,全自动进样方法进行测定。[结果]方法的测定限为1.40μg/L,相对标准偏差为1.95%-3.49%.回收率为89.99%-109.8%;已用于分析503例儿童血铅,结果满意。[结论]本法为一种理想的全血铅快速测定方法。     

石墨炉原子吸收法测定微量血铅的测量不确定度分析

[目的]建立微量全血中铅的测量不确定度分析的模式。[方法]用石墨炉原子吸收法测定。[结果]血样中铅浓度为61.1μg/L时扩展不确定度为1.9μg/L。[结论]该方法可用于全血中铅的测定。     

双组分混合脱蛋白石墨炉原子吸收法测定血铅

目的:建立双组分混合脱蛋白石墨炉原子吸收光谱法直接测定血铅的方法。方法:取适量全血,用5%HNO3-0.2%Triton X-100脱蛋白,高速离心(12000 rpm,5 min)后取上清液进样,以2%NH4H2PO4作为基体改进剂,在283.3 nm波长下用石墨炉原子吸收法测定。结果:方法的线性范围为1μg/L～60μg/L(r=0.9994),检出限为0.68μg/L,精密度为1.5%～4.3%,加标回收率为95%～106%。结论:该法准确、可靠,同时省去了消化步骤,操作简便、快速,适用于批量血铅的测定。     

混合化学改进剂用于测定血铅和尿铅的石墨炉原子吸收法

[目的]研究混合化学改进剂用于石墨炉原子吸收法测定血铅和尿铅的方法。[方法]通过比较5种化学改进剂的作用效果,优化石墨炉升温程序的测试条件,直接稀释血样、尿样进行铅含量的测定。[结果]以0．2％磷酸二氢铵＋O．05％硝酸镁为化学改进剂测血铅,以4％磷酸二氢铵＋6％抗坏血酸为化学改进剂测尿铅,血铅和尿铅测定线性范围分别为3．0—100．0μg／L和6．7—80．0μg／L,检出限分别为0．9μg／L和2．0μg/L L,相对标准偏差均小于5％,加标回收率为92．1％～104．O％。[结论]使用混合化学改进剂测定血铅和尿铅,灵敏、准确、重现性好,费用低廉,易于普及,适合大批量样品的检测。     

石墨炉原子吸收光谱法直接测定血中铅

[目的]建立稀硝酸稀释血样,石墨炉原子吸收直接测定血铅的方法。[方法]采用1．0％硝酸10倍稀释血样,10汕进样,标准加入法制备标准曲线,直接检测血铅。[结果]在实验条件下,血铅浓度在0．0～100．0μg/L之间存在线性关系（r=0．9992）。铅标准溶液25．0、50．0、75．0μg/L分别平行测定6次,其相对标准偏差为1．28％-2．74％。血样中加入铅标准溶液25．0、50．0、75．0μg／L,测得血铅回收率为95．7％-102．0％。[结论]该法灵敏度高、正确度好,操作简便快速,适宜血液中铅的测定。     

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.     

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.