测量不确定度在食品菌落总数检测中的评定

测量不确定度定义为表征合理地赋予被测量之值的分散性,与测量结果相联系的参数[1]。近年来在微生物检测领域,特别是在计量认证及实验室认可时,均需要给出检测结果的测量不确定度,而这方面报道文献较少。该文举例对食品微生物检测常见项目菌落总数进行了测量不确定度的评定。1检验方法在微生物检测中,各类食品菌落总数通常采用GB4789.2-2010《食品微生物学检验菌落总数测定》标准进行检测。该     

醋的微生物检验

[目的]修订醋的微生物检验方法.[方法]用氢氧化钠饱和溶液调节醋的pH值至7.参照GB/T4789规定方法进行菌落总数、大肠菌群、致病菌检验和方法学验证.[结果]用5个品牌的国产醋进行方法学验证,各标准菌株的菌回收率均大于70%,大肠菌群、沙门菌、志贺菌、金黄色葡萄球菌的阳性对照试验均成立.[结论]用氢氧化钠饱和溶液调醋的pH值进行菌落总数、大肠菌群、致病菌检验,方法可行.     

食品中菌落总数检测结果的不确定度评定

测量不确定度是评定测量水平的指标,是判定测量结果的依据,因此,正确评定测量不确定度对客观分析测量结果,进行实验室质量管理具有重要意义。食品的卫生状况与人民健康的关系极为密切。食品中微生物的检测是食品质量优劣的重要卫生指标之一,因此对食品中菌落总数进行测量不确定度的评定是非常必要的。本文以食品菌落总数检测为例,依据JJF1059-1999《测定不确定度评定与表示》[1]和GB4789.2-2010《食品微生物学检验菌落总数测定》[2]来建立食品的菌落总数检测结果的不确定度评定方法,并探讨其     

莱州市2000～2003年8类食品卫生监测结果分析

[目的 ]掌握莱州市食品卫生现状 ,指导食品卫生监督。 [方法 ]对莱州市 2 0 0 0～ 2 0 0 3年抽检的 8类食品按照相关标准进行检验和评价。 [结果 ]各类食品总合格率为 87 2 % ,合格率呈逐年上升趋势 ,差异有统计学意义 (P <0 0 1)。食品合格率由高到低顺序为粮食、酒、植物油、肉制品、碳酸饮料、糕点、调味品、冷冻饮品 ;主要超标指标分别为过氧化苯甲酰、杂醇油 (蒸馏酒及配制酒 )与菌落总数 (发酵酒 )、过氧化值、亚硝酸盐、菌落总数、过氧化值、菌落总数、菌落总数。 [结论 ]食品合格率逐年提高 ,应加强对碳酸饮料、调味品及冷冻饮品的监督监测 ,以主要不合格指标为该类食品的必检指标。     

食品中菌落总数检验结果不确定度分析

为了分析食品中菌落总数检验结果不确定度,利用平板菌落计数法测量食品中的菌落总数,通过对影响测量结果的不确定度分量的分析和量化,求出被测量菌落总数的标准不确定度和扩展不确定     

Petrifilm测试片法检测环节表面菌落总数的效果评价

[目的]探讨Petrifilm测试片法(测试片)检测环节表面菌落总数的效果。[方法]在实验室模拟食品生产加工环节表面的不锈钢平板上,人工污染不同浓度的标准菌株,分别用国标法和测试片法进行检测,比较两种方法检测环节表面菌落总数的符合率。[结果]国标法和测试片法检测结果差异无显著性(P>0.05)。[结论]测试片法可以作为食品行业环节表面菌落总数污染状况的检测方法。     

TTC应用于食品菌落计数的探讨

<正>菌落总数是判定食品被污染程度的标志,在实际工作中常因检验样品含有沉渣给菌落鉴别造成一定的困难。为有利于菌落计数,可在培养基中加入适量的2,3,5-氯化三苯基四氮唑(2,3,5-Triphcnyl tetrazolium chloride,分子式为 C19H15ClN4,以下简称 TTC),它能被细菌还原为红色物质使菌落呈红色[1]。本试验就TTC在食品菌落总数测定中的应用进行初步探讨。     

中山市2003年食品微生物监测结果分析

[目的]了解中山市食品微生物污染情况，为进一步进行监督监测提供科学依据。[方法]2003年抽、送检食品6418份，检测菌落总数、大肠菌群、霉菌、沙门菌、志贺菌。[结果]样品微生物指标检测合格率为86．69％，其中送检样品合格率为92．86％，抽检样品合格率为83．77％，送检样品高于抽检样品。肉及肉制品的合格率最低。[结论]中山市2003年的食品卫生微生物污染主要以菌落总数及大肠菌群为主，肉及肉制品的微生物污染较严重。     

影响蜜饯菌落总数测定因素的实验报告

目前,蜜饯菌落总数测定的方法,是按GB4789检验方法进行,菌落总数测定的培养时间为24±2h。但我们在实践中发现,检样在同一条件下,因培养时间和检样酸度不同,所得结果也不同,现将实验结果报告如下,有待进一步探讨。 1 材料与方法 1.1 操作方法:按GB4789进行菌落总数测定。 1.2 检样:日常送检的蜜饯、凉果。 1.3 培养基:营养琼脂培养基:营养琼脂(上海市医学化验所,批号84212)。 1.4 菌落总数计数方法:用肉眼和10倍放大镜,同一检样结果由两名检验人员分别计数。     

科学城桶装饮用纯净水常规卫生检测结果分析

[目的]分析科学城饮用纯净水常规卫生检测结果,为卫生监督提供依据。[方法]按照国家标准进行部分感官指标、理化指标、微生物指标等项目的检验。[结果]感官指标及理化指标合格率100%;微生物指标合格率92.18%,微生物指标中主要是菌落总数超标,其中手工灌装的纯净水菌落总数合格率为79.17%,具备全自动生产线的纯净水菌落总数合格率为96.53%。[结论]强化卫生质量管理,生产企业实施食品卫生量化分级管理。     

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.     

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.