职业接触铍工人尿中铍的原子吸收光谱法研究

本文描述了一个加基体改良剂后直接测定尿中铍的石墨炉原子吸收光谱法。基体改良剂由硝酸镁、硝酸镧、硝酸和硫酸组成。方法的灵敏度、测定范围、回收率和变异系数分别为0.09～0.42μg/L、0～30μg/L、87.6～101％(2～20μg/L)和4.2～9.0％。灵敏度和测定范围与石墨管的性能有关。尿中共存的元素不干扰铍的测定。在班前收集工人尿样,尽早加入等体积的基体改良剂后保存。     

石墨炉原子吸收法测定尿中的铊

目的:建立准确可靠的尿中铊的快速分析方法.方法:用1%硝酸酸化尿样,以PdCl2为基体改进剂消除干扰,用石墨炉原子吸收法直接测定尿铊.结果:铊在0～100μg/L线性良好,相关系数为0.9991,方法检出限0.54μg/L,最低检出浓度1.1μg/L,高中低铊含量尿样日内精密度分别为4.0%、1.4%、3.0%,回收率98.8%～101.5%.结论:该方法简单快速、精密度和稳定性很好,可以满足尿中铊的测定.     

电感耦合等离子体质谱法测定兔尿样、血浆及组织器官中的总铂

采用电感耦合等离子体质谱法测定兔尿样、血浆和组织器官中的总铂(Pt),兔血浆和尿样适当稀释后直接测定,脏器类样品湿法消解后测定。在0.02～50.00μg/L范围内方法线性良好,相关系数为1.00;尿样精密度良好,批内相对标准偏差2.17%～3.77%,批间相对标准偏差3.54%～4.35%,加标回收率100.90%～103.65%;血浆样品批内相对标准偏差1.57%～2.27%,批间相对标准偏差2.47%～2.64%,加标回收率100.14%～102.30%;组织样品批内相对标准偏差3.47%～4.45%,批间相对标准偏差3.55%～5.61%,加标回收率96.55%～97.60%;兔尿、血浆和脏器样品的方法定量限分别为0.18μg/L、0.20μg/L、0.03μg/g。本方法检出限低,灵敏度高,精密度好,适用于测定血浆、尿样及动物脏器中总铂含量,可为铂类抗癌药物药理、毒理学研究提供技术支持。     

尿中铊石墨炉原子吸收光谱法直接测定

目的 建立石墨炉原子吸收光谱法直接测定尿中铊的方法.方法 比较了几种基体改进剂的不同效果,最后选择以二氯化钯一硝酸镁为基体改进剂直接测定尿中铊.结果 尿样经1:1稀释后,加入5μl浓度为1.66 g/L PdCl2-0.6 g/L Mg(NO3)2混合液作化学改进剂直接测定尿中铊.用工作曲线法定量,方法线性范围0～80μg/L,相关系数r=0.9998,进样量20μl时,检出限为0.43μg/L,回收率为97.6%～103.9%,RSD为1.82%～6.15%.结论 用二氯化钯-硝酸镁为基体改进剂,尿样经适当稀释,可直接进样,石墨炉原子吸收光谱法直接测定,方法简便、快速、灵敏准确.     

石墨炉原子吸收光谱法测定尿中镉

目的:探索简便快速准确检测尿中镉的方法。方法:采用Triton X-100稀释首次350℃通氧灰化,再次450℃灰化、原子化温度1500℃,0.1%硝酸钯+0.06%硝酸镁作为基体改进剂,石墨炉原子吸收法测定。结果:增加通氧灰化能有效消除积炭干扰,线性范围为0μg/L～5μg/L,回收率为97.7%～104%,检测限为0.24μg/L,精密度测定相对标准偏差为2.7%～5.9%。结论:本方法标准曲线配置简便、样品测定快速准确灵敏,能满足大批量尿样的检测工作。     

石墨炉原子吸收分光光度法直接测定全血中镍

目的:建立石墨炉原子吸收分光光度法测定全血中镍的方法。方法:以0.15 g/L Mg(NO3)2/0.1%Triton X-100/0.2%HNO3(V/V)混合液为稀释液、1 mg/ml钯溶液为基体改进剂,对血液适当稀释后,直接用石墨炉原子吸收分光光度法测定镍的含量。结果:方法最低检出限(n=10)为0.92μg/L,平均特征质量为23.6～28.5pg/0.0044(A),线性范围为0μg/L～160μg/L,相对标准偏差0.6%～3.9%,回收率为99.9%～103.0%。结论:方法具有简便、快速、回收率高、精密度高的优点,适用于全血中镍含量的测定。     

石墨炉原子吸收法直接测定尿中的铅

目的:建立一种直接稀释-石墨炉原子吸收法测定人体尿液中铅含量的方法。方法:用硝酸酸化,以0.2%Triton X-100溶液为基体改进剂稀释尿样,SpectAA220原子吸收分光光度计(具GTA110石墨炉原子化器、氘灯背景校正),自动进样方法进行测定。结果:方法的线性范围为0μg/L～50μg/L,相关系数为0.9996,RSD为4.0%～10.0%,回收率为93%～98%,方法的检出限为1.2μg/L。结论:该方法精密度好、准确度高、快速简单,能很好地满足尿液中铅含量测定的要求。     

尿中镍石墨炉原子吸收光谱法的改进

目的通过评估镍的4个不同特征谱线的灵敏度、稳定性及峰形情况以及尿样经5种基体改进剂的处理,优化石墨炉测定条件,以方法线性、灵敏度、精密度、加标回收作为评价指标进行方法改进。方法用10 g/L磷酸氢二铵溶液(基体改进剂)将尿样稀释5倍后,在341.48 nm波长下采用石墨炉原子吸收光谱法直接测定尿中镍。结果 4个波长中323.30 nm测定吸光度值明显低于其他3个,差异有统计学意义(P<0.05)。另外3个波长中,341.48 nm波长下测定的灵敏度、稳定性和峰形较好。该方法曲线浓度在2.7～100.0μg/L范围内呈线性关系(r>0.999),尿镍测定范围为13.5～500.0μg/L,检出限为0.8μg/L,定量下限2.7μg/L,加标回收率为95.4%～101.3%,尿样在4℃下至少保存7天。结论本方法操作简便,准确度、精密度较高,适用于正常人及职业性接触人群尿中镍的测定。     

尿镉的微分电位溶出法规范化研究

尿样先经盐酸酸化至总浓度0.3mol/L,在冰箱内可保存二周,作适当稀释后即可直接测定。尿镉浓度在0～25μg/L范围内呈直线相关,r=0.999。尿样加标回收率为100～102%。最低检测浓度为0.2μg/L。尿中存在的其他元素对镉的测定无干扰。     

2006年贵州省黔东南州8～10岁儿童尿碘含量

目的 为了解黔东南州儿童碘营养状况,为今后碘缺乏病防治工作提供科学依据.方法 于2006年选择黔东南州16县(市)80所小学8～10岁学生采集3 200份尿样,用过硫酸铵-砷铈催化分光光度法测定尿碘.结果 3 200份尿样的尿碘中位数为362.9μg/L,尿碘≥100μg/L的尿样占98.00%(3 136/3 200),其中尿碘≥300μg/L的尿样占65.31%(2 090/3 200),尿碘＜20μg/L和＜50μg/L的尿样分别只占0.12%(4/3 200)和0.44%(14/3 200).结论 黔东南州各县(市)达到消除IDD的标准,但儿童碘营养水平偏高,碘盐浓度还需下调.     

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.     

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.     

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.     

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.