分光光度法间接测定白酒中甜蜜素

目的：探讨研究一种适用于白酒样品中的甜蜜素测定方法。方法：用乙醚将甜蜜素从酸化后的样品中提取出来，挥去乙醚，通过测定其与亚硝酸酯化后生成的硫酸根含量间接测定甜蜜素。结果：线性范围0～0．35g／kg，方法最低检出限0．02g／kg，加标回收率为86．7％-105％，精密度RSD为8．58％（0．060g／L）、3．75％（0．250g／L）与3.66％（0．500g／L）。结论：方法成功应用于白酒样品的测定，结果满意。     

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。     

毛细管柱气相色谱法测定食品中的甜蜜素

目的：建立毛细管柱气相色谱法测定食品中的甜蜜素的方法。方法：采用适当的样品处理方法，应用弱极性的HP-1毛细管柱取代填充柱检测食品样品中的甜蜜素。结果：在最佳分析条件下，样品中的甜蜜素经酯化后在0.50～3．0mg/ml范围内有良好的线性（r=0．9998），回收率为94．1％～97．6％，相对标准偏差3．0％～4.9％。结论：相对于国家标准方法推荐的填充柱，毛细管柱的柱效高，通用性好，结果更易重复，是食品中甜蜜素检测的另一选择。     

炉内直接消化石墨炉原子吸收法快速测定乳制品中铅和铜

目的：建立一种无需事先消化、快速测定乳制品中铅和铜的炉内直接消化石墨炉原子吸收方法。方法：样品经水溶解或稀释后直接进样测定。结果：对于婴儿配方奶粉，铅的检出限为0．02mg／kg（3σ，n=11）；含乳饮料样品铅的检出限为0.002mg／kg（3σ，n=11）。铅的加标回收率为93．8％～107．0％，相对标准偏差在0．7％～4．8％之间（n=5）；铜的加标回收率为94．6％～109．0％，5次测定的相对标准偏差在1．2％～4．7％之间。结论：在这些条件下，乳制品中铅和铜可以在尽可能避免沾污和最少的样品前处理步骤下被快速准确测定。     

测定饮料中甜蜜素的毛细管柱气相色谱方法研究

目的建立饮料中甜蜜素测定的毛细管柱气相色谱方法。方法对分离甜蜜素的色谱条件、放置条件和衍生条件进行优化,建立饮料中甜蜜素测定的毛细管柱气相色谱方法。结果在优化的条件下,甜蜜素在0．02～10．0g／L范围内线性关系良好,相关系数r=0．9992;以3倍信噪比计算,该方法的检出限为1．2×10～g／L。对样品6次测定的相对标准偏差（RSD）〈2．1％。对甜蜜素样品的低、中、高3种浓度的加标回收率为99．6％～104．9％。结论通过对气相色谱条件、甜蜜素放置条件和衍生条件的优化,建立了毛细管柱分离甜蜜素的方法。由于毛细管柱分离效率高,能较好避免其他杂质的干扰,因此,该分析方法可用于基质更为复杂的样品中甜蜜素的测定,具有较好的推广意义。     

湿法消解-原子荧光光谱法同时测定油脂样品中砷和汞

目的：建立原子荧光光谱同时测定油脂样品中砷和汞的方法。方法：硝高酸消解油脂样品，在最佳仪器、反应条件下同时测定其中的砷和汞。结果：检出限：As 0．087ng／ml、Hg 0．0065ng／ml。线性范围：As 0～20ng／ml，相关系数0．9999；Hg 0～4ng／ml，相关系数0．9996。精密度：测定10ng／mlAs、2ng／mlHg混合标准试液得到的相对标准偏差（RSD），砷1．6％、汞2．7％。样品加标回收率：As95．5％～101．4％、Hg92．5％～102．0％之间。结论：该方法具有较高的灵敏度、准确度、精密度和较低的检出限，满足了油脂样品中砷和汞的同时测定要求，同时也适合于其它食品、生物材料等样品的测定。     

高效液相色谱法同时测定多种食品添加剂方法研究

[目的]建立高效液相色谱法同时测定食品中安赛蜜、苯甲酸、山梨酸、糖精钠。[方法]水超声提取样品,必要时用亚铁氰化钾溶液（106g／L）和乙酸锌溶液（220g／L）净化;样液采用Kromasil C18柱（150mm×4．6mm,5μm）色谱柱,流动相为甲醇-0．02mol／L乙酸铵溶液（6：94,V／V）,二极管阵列检测器进行检测;以保留时间和紫外吸收光谱图结合定性,外标法测定食品种4种食品添加剂含量。[结果]4种食品添加剂的检出限分别为安赛蜜9．00×10^-5mg／ml、苯甲酸1．20×10^-4mg／ml、山梨酸1．00×10^-4mg／ml、糖精钠1．60×10^-4mg／ml;各组分回收率在89．0％～100．0％之间;各组分测定RSD均小于5％。[结论]该法特异性强、灵敏度高,操作简便快速,测定结果可靠,适用于食品中上述4种添加剂的常规分析。     

微波消解-原子吸收分光光度法测定茶叶中的微量元素

目的：建立微波消解-原子吸收分光光度法测定茶叶中4种微量元素的分析方法。方法：样品经微波消解，用原子吸收分光光度法测量微量元素。结果：方法检出限分别为Cu：0．022μg／ml、Fe：0．15μg／ml、Mn：0．021μg／ml、Zn：0．060μg/ml；线性范围分别为Cu：0．2—3．0μg／ml、Fe：0．3—5．0μg／ml、Mn：0．2—4．0μg／ml、Zn：0．1～0．6μg／ml，相关系数r≥0．999；相对标准偏差（RSD）分别为Cu：2．18％、Fe：8．02％、Mn：3．12％、Zn：7．15％；回收率分别为Cu：99．4％-102．8％、Fe：94．7％～104．7％、Mn：98．9％～101．1％、Zn：87．5％-108．1％。结论：该法消解效果理想，检出限低，线性范围较宽，精密度好，准确度较高。     

气相色谱法测定水、土壤中六甲基磷酰三胺

目的：初步建立气相色谱法测定水、土壤中六甲基磷酰三胺（HMPA）的方法。方法：在碱性条件下，样品经氯仿萃取，毛细管气相色谱一氮磷检测器（NPD）测定，以保留时间定性，峰面积（或峰高）外标法定量。结果：在最佳分析条件下，样品中HMPA在1～2000μg／L范围有良好线性关系（r〉0．99），方法检出限为1ng，回收率为86％～101％，精密度为6％（0．05μg／ml），4．6％（1．0μg／ml）。结论：本法测定水、土壤中HMPA简便、快速、灵敏、准确。     

薄层色谱法测定食品中苯甲酸的方法改进

当食品中苯甲酸和甜蜜素同时存在需用薄层分析测定苯甲酸时，两者比移值（Rf）很接近，不能完全分离而影响测定结果。本文通过改变展开剂中各组分的分配比，能够较好地分离并可同时测定食品中苯甲酸和甜蜜素。一、材料与方法1.仪器：电吹风机、层析缸、微量注射器（10μl）、玻璃板（10×20cm）2．试剂：（l）聚酷胺粉（200目）无锡县生化制品厂生产。（2）正了醇、无水乙醇、液氢水、异丙醇、乙醚、氯化钠（以上试剂均为分析纯）。门）苯甲酸标准液：精密称取苯甲酸0·10009，用乙醇定容至50ml，即得Zing／ml。（4）甜蜜素标准溶液：精密…     

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 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.     

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.     

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.     

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.