3,5-diBr-DMPAP选择性光度法测定发样中微量铁

目的 :建立一种快速、简便、灵敏分光光度法测定发样中微量铁。方法 :在非离子型表面活性剂聚氧乙烯月桂醚 (Brij- 35 )及聚氧乙烯异辛基苯基醚 (TritonX - 10 0 )存在下 ,用 2 - (3,5 -二溴 - 2 -吡啶偶氮 ) - 5-二甲氨基酚 (简称 3,5 -diBr-DMPAP)作显色剂直接光度法测定发样中微量铁。结果 :该方法在pH4 .0的乙酸 -乙酸钠缓冲液中 ,以 75 0nm为测定波长 ,可选择性测定发样中微量铁 ,线性范围为 0～ 12 5 μg/ 10ml,表观摩尔吸光数为 2 .80× 10 4L/ (mol·cm) ,回收率为 97.9%～ 10 3.3%。结论 :该法具有操作快速、简便、结果灵敏可靠等优点 ,适合临床应用。     

顶空气相色谱法测定水中微量硫氰酸根

水中微量SCN~-的测定,目前国家还未规定标准检验方法,本文根据SCN~-能与氯胺T反应生成CNCI的原理,应用顶空气相色谱法直接测定水中微量SCN~-,操作简便、快速、准确灵敏,其最低检测限为1×10~(-6)μg/ml。     

5-Br-DMPAP选择性光度法测定发样中微量铁

目的 :建立一种快速、简便、灵敏分光光度法测定发样中微量铁。方法 :在表面活性剂 Triton X- 10 0存在下 ,用 2 - (5 -溴 - 2 -吡啶偶氮 ) - 5 -二甲氨基酚 (简称 5 - Br- DMPAP)作显色剂直接光度法测定发样中微量铁。结果 :该方法在 p H4.0的乙酸 -乙酸钠缓冲液中 ,以 746 nm为测定波长 ,可选择性测定发样中微量铁 ,本法线性范围为 0～ 10 μg/ 10 m l,表现摩尔吸光数为 2 .75× 10 4L/ (mol.cm) ,回收率为 98.4%～ 10 1.3%。结论 :该法具有操作快速、简便、结果灵敏可靠等优点 ,适应临床应用     

3,5-diBr-DMPAP光度法测定全血铁

目的 :建立一种快速、简便、灵敏分光光度法测定全血中微量铁。方法 :在表面活性剂 Tri-ton X-1 0 0存在下 ,用 2 -(3 ,5 -二溴 -2 -吡啶偶氮 ) -5 -二甲氨基酚 (简称 3 ,5 -di Br-DMPAP)作显色剂直接光度法测定全血中微量铁。结果 :该方法在 p H4.0的乙酸 -乙酸钠缓冲液中 ,以 746nm为测定波长 ,可选择性测定全血中微量铁 ,本法线性范围为 0～ 1 0μg/ 3 .4ml,表观摩尔吸光数为 2 .75× 1 0 4 L/ (mol· cm) ,回收率为 98.4%～ 1 0 1 .3 %。结论 :该法具有操作快速、简便、结果灵敏可靠等优点 ,适合临床应用     

气相色谱法测定工作场所空气中苯乙烯

目的提出空气中微量苯乙烯测定的新方法。方法空气中苯乙烯用活性炭管采集,二硫化碳解吸,OV351柱分离。结果方法灵敏度高,检出下限3×10-3μg/ml,在0.05~5μg/ml范围内线性关系良好,相关系数r>0.999,精密度高,变异系数CV%<5%,平均回收率达79.7%。结论本法简便、快速、灵敏度高,结果准确可靠,适用于空气中苯乙烯的测定。     

工作场所空气中TNT的气相色谱测定法

目的　探讨一种测定微量三硝基甲苯 (TNT)的方法。方法　空气中的TNT用玻璃纤维滤纸采集 ,甲苯解吸 ,DB -17MS毛细柱分离。结果　方法检出下限为 3× 10 -3 μg/ml ,在 0 0 5～ 5 μg/ml范围内线性关系良好 ,相关系数 r >0 999,精密度高 ,变异系数CV <5 % ,平均回收率达 98%以上。结论　该法简便 ,快速 ,灵敏度高 ,结果准确可靠 ,适合于空气中TNT的测定。     

水中甲醛的动力学分光光度测定法

目的研究水中甲醛的动力学分光光度测定法。方法在磷酸介质中,微量甲醛对溴酸钾氧化甲基橙褪色有显著的催化作用,用分光光度法测定反应速度与其量的变化关系,从而测定甲醛的含量。结果该方法的线性范围为0.13～3.00μg/ml,检出限为4.7×10-5mg/ml,相对标准偏差为1.5%～3.3%,回收率为97.3～102.0%。结论该方法简便、快速,灵敏度较高,可用于水样中微量甲醛的测定。     

催化动力学光度法测定水中痕量铬(Ⅵ)

目的:建立了催化动力学光度法测定水样中痕量Cr(Ⅵ)的新方法。方法:在硫酸介质中,痕量Cr(Ⅵ)催化过硫酸铵氧化邻甲氧基酚显色,其化合物的最大吸收波长为513nm。结果:方法的线性范围为01016～116μg/25ml Cr(Ⅵ),检出限为5142×10-10g/ml Cr(Ⅵ),相对标准偏差(RSD)<3.27%,样品加标回收率为9716%～10111%。结论:该法用于环境水样中微量铬含量的测定快速、准确、简便。     

荧光分光光度法测定保健品中的微量蛋白质

荧光分光光度法测定微量蛋白质,蛋白质与茚三酮和苯甲醛形成缩合物的荧光强度与蛋白质的含量在1.0×10~(-5)～5.0×10~(-4)mol/L范围呈现良好的线性关系,检测限为2.7×10~(-6)mol/L;对6.0×10~(-5)mol/L蛋白质的11次检测,相对标准偏差为1.7%。考察了十几种常见离子的干扰,并成功地应用于保健品中微量蛋白质及血清中总蛋白质的测定。     

比色法和荧光强度法快速测定微量的唾液溶菌酶

本文增加溶菌酶(LZM)活性微量比色法和微量荧光强度法的底物浓度,缩短微量比色法的反应时间,酶活性的检出范围处于5.0～100.0μg/ml之间,只需50μl唾液样品,就可直接测定。应用两方法测定95名10～14岁儿童唾液LZM活性,结果分别为34.64±15.19μg/ml和34.16±14.72μg/ml。研究结果表明:此二方法具有微量、快速、简便、准确的优点。     

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.