单扫描极谱法测定尿中锰

目的探索用单扫描极谱法测定尿中锰的含量。方法在0．15mol／L酒石酸钾钠溶液、0．75mol／L亚硫酸钠溶液、7．0mol／L乙二胺溶液体系中，采用单扫描极谱法，锰在-1790mV处出现灵敏而清晰的波峰。结果其峰电流与锰的含量成正比，测定样品，结果显示相对标准偏差〈2％，加标回收率可达93．3％～98．0％。结论本法与磷酸-高碘酸法相比较，相对标准偏差〈3．5％，且本法体系稳定，选择性好，灵敏度高。     

单扫描极谱法测定猪尿中克伦特罗残留量

目的：研制猪尿中克伦特罗的极谱分析方法。方法：样品经正己烷提取，用拟定的极谱分析方法进行定性和定量测定。结果：在盐酸-高锰酸钾-草酸介质中，克伦特罗峰电位为-870mv（vs．SCE）。克伦特罗浓度在0.5～4．0μg／ml之间线性关系良好，相关系数r=0．9994，回归方程Y=9．563X-32．15。最低检出量为1．2μg。相对标准偏差（RSD）平均为7．1％（n=7），加标平均回收率为91．5％。结论：建立的单扫描极谱法准确、快速、简便、仪器价廉，适于实验室检测猪尿中克伦特罗残留量。     

氯酸法用于血清碘测定的方法学研究

目的：建立快捷、易行、准确的血清碘测定方法。方法：单纯利用氯酸在130℃恒温下消化样品，以分光光度法测定血清碘。结果：方法的线性范围为0～250mg／L时r=-0．999～-0．9999；最低检测浓度为5．8mg／L（取样量为0．20ml）；精密度：测定血清碘含量为50．7、82．5、122．4mg／L时，其变异系数（CV）分别为5．2％、3．7％、2．6％（n=6）；准确度：对低、中、高3种不同碘含量的血清样品加碘标平均回收率分别为97．8％、96．5％、95．6％（n=6），总平均回收率为96．6％（范围：91．2％～103．3％）。结论：测定方法操作简单、快速，检测成本低，灵敏度、重现性、准确度均较高，适用于流行病学调查及科研工作中血清碘的测定。     

液质联用测定猪肌肉组织中的克伦特罗

目的：建立液质联用法测定猪肌肉组织中克伦特罗的方法。方法：采用0．2mol／L高氯酸溶液水解样品，碱化后乙醚提取克伦特罗，选用Waters Atlantis^TM C18色谱柱，流动相甲醇-0．1％甲酸（30：70），通过质谱对样品进行确证。结果：盐酸克伦特罗的线性范围为2．5～50ng／ml，绝对线性方程Y=0．0394X＋0．0283（r=0．9997），相对线性方程Y=0．0414X-0．0275（r=0．9993）；方法的绝对回收率为66．4％（25ng／ml）和60．1％（5ng／ml）；相对回收率为100．9％（25ng／ml）和100．3％（5ng／ml）；方法的最低检出限为1．0μg盐酸克伦特罗／kg猪肉。结论：本法操作简便，结果准确，可用于猪肌肉组织中克伦特罗的含量测定。     

高效液相色谱-二极管阵列检测器法检测饮料中Vc的研究

目的：建立高效液相色谱（HPLC）-二极管阵列检测器（PDA）法测定饮料中Vc含量的检测方法，并探讨更确切的定性方法。方法：用0．01mol／L盐酸溶解稀释样品，经0．45μm滤膜过滤，以0．02mol／L乙酸铵-甲醇（7＋3）作流动相，采用Diamonsial C18柱分离，在比对保留时间的基础之上，对照样品与标准Vc的光谱形状、最大吸收波长等特征。结果：只有保留时间和光谱特征两项指标都符合才能确认，增强了定性的确定性。方法线性范围为1.0-40．0μg／ml，r=0．9998，加标回收率为97．5％-105％，RSD为2．1％-4．6％，检出限为0．5ng（S／N=3）。结论：该方法简便、快速，定性能力强，易于普及，适于食品中Vc的快速测定。     

单扫描极谱法测定居室内空气中甲醛

目的探索用单扫描极谱法测定居室内空气中的甲醛浓度。方法在0．07mol／L盐酸苯肼溶液—0．2mol／LNaCl溶液体系中，甲醛在-700mV处出现灵敏而清晰的波峰。于JP-303极谱分析仪上测定，原点点位-350mV，终止点位-1000mV，三电极，二次导数，在-700mv处读其二次导数波峰。根据峰电流与相应甲醛含量绘制标准曲线，再根据样品峰电流大小，计算样品中甲醛含量。结果其峰高与甲醛的含量成正比。在0．4ml盐酸苯肼、1．0ml氯化钠底液条件下，本方法检出范围为0．021～2．0μg／10ml，在15min～4h内峰电流稳定不变。本法与GB／T18204．25～2000相比较，相对标准偏差〈3．5％，回收率为94％-102％。结论本法具有简便、快速、易操作、精密度好、灵敏度高等优点。     

二阶导数单扫描示波极谱法测定食品中甲醛的含量

目的：建立食品中甲醛的快速测定方法。方法：利用甲醛与盐酸苯肼生成盐酸苯腙衍生物的反应，用二阶导数单扫描示波极谱法测定生成物。结果：生成物在-700mV产生一个极为灵敏的二阶导数还原波，利用该极谱波测定甲醛，无须除；检出限为0．003mg／L，相对标准偏差(RSD)为4．85％(n=6)，采用此方法对16种食品中的甲醛作了测定，回收率在96％-102％之间。结论:二阶导数单扫描示波极谱法是一种快速、简便、准确的食品中甲醛含量的测定方法，所测16种食品中甲醛的含量在0．592mg／kg-112mg／kg范围内。     

柱后衍生-高效液相色谱法测定食品中游离维生素B1

目的：建立柱后衍生-高效液相色谱法测定食品中游离维生素B1含量的方法。方法：样品以0．01mol／L盐酸提取，流动相选用含5％甲醇的0．05mol／L醋酸钠溶液，流速为1．0ml／min，经Krommil C18柱分离，以0．025％的碱性铁氰化钾作衍生剂，流速为0．30ml／min，经荧光检测器检测定量（Ex=375nm，Em=435nm）。结果：被测组分在浓度为0．01-10mg／ml时，浓度与峰面积呈良好的线性关系（r=0．9999）；加标回收率为85．0％-104．6％；方法检出限0．005μg／ml。方法的精密度良好，相对标准偏差（RSD）小于3．0％。结论：方法快速、简便、准确。     

食品中无机砷和总砷的流动注射氢化物发生原子吸收光谱法测定研究

目的：建立食品中无机砷和总砷的流动注射氢化物发生原子吸收光谱法测定方法。方法：总砷测定，样品经硝酸-高氯酸-硫酸微波消解破坏有机物，无机砷测定，样品以6mol／L盐酸提取，样液与硼氢化钾-氢氧化钾溶液，进入流动注射氢化物发生器，产生的砷化氢经高纯氮气吹入石英管原子化器，测定197．3nm处的吸光值。结果：砷含量0～8ng／ml范围内线性关系良好，相关系数r=0．9993（n=3），回归方程Y=0.0462X＋0．0015，检出限为2μg／kg，样品分析的精密度试验，相对标准偏差为4.2％-6．3％，样品分析的准确度试验，回收率为92．6％～107．3％。结论：方法灵敏度高，快速简便。     

银连片中绿原酸成分的含量测定研究

目的建立银连片中金银花的绿原酸的含量测定方法。方法采用高效液相色谱法测定金银花中绿原酸的含量;采用EclipseXDB-C18（250mm×4．6mm,5μm）,流动相：乙腈-1％冰醋酸溶液（6：94）;检测波长为327nm;流速1．0ml／min,柱温为50℃。结果绿原酸在0．08～1．60μg（r=0．9999）范围内呈良好线性关系,精密度试验BSD为0．76％（n=6）,加样回收率99．6％,BSD为1．63％。结论本法简便、快捷,可作为银连片质量控制的依据。     

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.     

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.     

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.     

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.