高效液相色谱法测定猪肌肉组织中磺胺类药物的研究

目的:为了解动物性食品中兽药残留水平,探讨其污染来源,评价其膳食安全性,因此建立猪肌肉组织中磺胺嘧啶、磺胺甲恶唑、磺胺对甲氧嘧啶、磺胺喹恶啉残留量的高效液相色谱(HPLC)测定方法。方法:经处理过的样品用乙腈提取两次,将乙腈过无水硫酸钠层后挥干乙腈,正己烷洗涤净化,经过净化后进行高效液相色谱仪测定(C18柱),本方法以甲醇、水为流动相梯度洗脱,柱温35℃,在波长275 nm处测定。结果:在3个加标水平进行加标回收实验,回收率磺胺嘧啶(SD)为81.7%～94.1%,磺胺甲恶唑(SMZ)为80.0%～94.5%,磺胺对甲氧嘧啶(SMD)为80.7%～102.9%,磺胺喹恶啉(SQX)为80.3%～93.6%。线性范围均在1～200μg/m l,检出限为0.01 mg/kg,定量限为0.05 mg/kg。结论:高效液相色谱(HPLC)测定猪肉中磺胺嘧啶、磺胺甲恶唑、磺胺对甲氧嘧啶、磺胺喹恶啉的残留是一种灵敏度较高、检测限较低、简单易行的方法,易于在基层推广应用。     

兰州地区鲜牛乳与消毒牛乳中抗菌类兽药残留的对比研究

〔目的〕了解兰州地区鲜 (生 )牛乳与消毒牛乳中抗菌类兽药残留水平。〔方法〕采用高效液相色谱法同时测定 8种抗菌类兽药的残留量。〔结果〕鲜 (生 )牛乳与消毒牛乳中抗菌类兽药残留检出率分别为磺胺 7.41%(2 .5 0 %)、磺胺嘧啶为 4.44 %(1.67%)、甲氧苄基嘧啶为 12 .5 9%(10 .83 %)、磺胺甲口恶唑为 2 1.48%(12 .5 0 %)、土霉素为 13 .3 3 %(7.5 0 %)、四环素为 10 .3 7%(3 .3 3 %)、金霉素为 5 .93 %(5 .80 %)、氯霉素为 40 .47%(3 .3 3 %)。〔结论〕鲜 (生 )牛乳中抗菌类兽药残留情况严重 ,市售消毒牛乳质量基本有保障。     

反相高效液相色谱法同时测定广州部分地区肉类4种抗生素的残留量

〔目的〕高效液相色谱法同时测定肉类中磺胺嘧啶 (SD)、磺胺二甲基嘧啶 (SMZ)、土霉素 (OTC)、磺胺甲恶唑(SN2 )抗生素的残留量。〔方法〕色谱柱为ODS -C1 8,以 2mmol L醋酸铵 :乙腈 :80 :2 0 (pH =2 .0 3 )为流动相 ,流速 0 .8ml/min ,486紫外检测器 ,检测波长为 2 70nm。〔结果〕该方法各抗生素的线性范围均为 0 .0 1～ 1.0 μg/ml ,相关系数均为 0 .99以上 (n =5 ) ;最低检测限为 0 .0 1μg/ml;回收率均为 95 .6%～ 10 6.0 % ;日内、日间变异系数均在允许范围内 (小于 15 % )。〔结论〕该方法操作简便 ,是动物性食品残留抗生素的快速而准确的检测方法。     

固相萃取-超高效液相色谱-串联质谱法测定水样中17种磺胺类抗生素

目的 建立固相萃取-超高效液相色谱-串联质谱法测定水样中17种磺胺类抗生素药物(磺胺吡啶、磺胺嘧啶、磺胺甲恶唑、磺胺噻唑、磺胺甲基嘧啶、磺胺二甲恶唑、磺胺二甲异恶唑、磺胺甲噻二唑、磺胺喹恶啉、磺胺苯吡唑、磺胺多辛、磺胺二甲氧嗪、磺胺醋酰、磺胺苯甲酰、磺胺二甲嘧啶、磺胺间甲氧嘧啶和磺胺对甲氧嘧啶)的方法。方法 采用HLB固相萃取柱富集纯化水样中磺胺类抗生素,经CSH C18(2. 1 mm×100 mm,1. 7μm)色谱柱分离,在电喷雾正离子多反应扫描监测模式下进行测定。结果 17种磺胺类抗生素在一定的浓度范围内线性关系良好,相关系数(r)0. 99。方法检出限(LOD)为0. 014 ng/L～0. 293 ng/L,定量限(LOQ)为0. 046 ng/L～0. 977 ng/L。在2. 0 ng/L、10. 0 ng/L、50. 0 ng/L 3个添加水平下,其加标回收率为74. 8%～108. 6%,相对标准偏差为0. 14%～8. 61%。结论 该方法灵敏度高、准确性好,可适用于水样中磺胺类抗生素的检测。     

超高效液相色谱测定鸡蛋中11种磺胺类化合物

目的:建立超高效液相色谱(UPLC)-PDA检测器快速测定鸡蛋中11种常用磺胺类化合物(磺胺、磺胺噻唑、磺胺吡啶、磺胺甲基嘧啶、磺胺多辛、磺胺甲二唑、磺胺间甲氧嘧啶、磺胺氯达嗪、磺胺二甲异恶唑、磺胺二甲氧嘧啶、磺胺喹恶啉)的方法。方法:固相萃取和超高效液相色谱相结合,Waters Acquity BEH C18柱(1.7μm,2.1 mm×100 mm),0.02 mol/L醋酸胺水溶液(pH=4.2) 乙腈=80 20为流动相,流速0.3 ml/min,柱温为40℃,使用PDA二极管阵列检测器检测定量,检测波长为265 nm。结果:提取方法计算的最低检测限磺胺、磺胺噻唑、磺胺吡啶、磺胺甲基嘧啶、磺胺间甲氧嘧啶、磺胺氯达嗪和磺胺二甲异恶唑为4μg/kg,磺胺多辛、磺胺甲二唑、磺胺二甲氧嘧啶、磺胺喹恶啉为6μg/kg,回收率能达到80.3%~96.2%,相对标准偏差小于5%。结论:本方法操作简单、准确、快速,满足日常大批量快速分析要求。     

高效液相色谱质谱测定肉品中的磺胺二甲嘧啶

〔目的〕用高效液相色谱电喷雾质谱 (ESI -MSn)测定肉品中的磺胺二甲嘧啶。〔方法〕通过多级质谱对阳性样品确证。〔结果〕以二级碎片做定量离子 ,磺铵二甲嘧啶测定线性范围为 (2 5～ 40 0 ) μg L ,最低检出浓度为 5 μg L。〔结论〕方法简便快速 ,检出限低。     

动物性食品中11种兽药残留量的高效液相色谱(HPLC)法测定

[目的]建立动物性食品中磺胺、喹乙醇、磺胺嘧啶、磺胺噻唑、磺胺甲嘧啶、甲氧苄啶、磺胺二甲嘧啶、呋喃唑酮、磺胺甲基异噁唑、磺胺(二甲)异噁唑、磺胺喹噁啉残留量的高效液相色谱(HPLC）测定方法。[方法]碎肉分两次用乙腈提取，正己烷洗涤净化，将乙腈层过无水硫酸钠后挥干乙腈，用pH2．5 KH2PO4 CH3CN(1 1)洗脱、溶解后测定。[结果]平均回收率磺胺82．1％、喹乙醇76．5％、磺胺嘧啶77．0％、磺胺噻唑75．9％、磺胺甲嘧啶80．5％、甲氧苄啶89．6％、磺胺二甲嘧啶78．2％、呋喃唑酮76．0％、磺胺甲基异嗯唑76．5％、磺胺(二甲)异嗯唑69．9％、磺胺喹嗯啉64．1％。检出限：磺胺0．023mg／kg、喹乙醇0．050mg／kg、磺胺嘧啶0．030mg／kg、磺胺噻唑0．052mg／kg、磺胺甲嘧啶0．046mg／kg、甲氧苄啶0．11mg／kg、磺胺二甲嘧啶0．075mg／kg、呋喃唑酮0．068mg／kg、磺胺甲基异口恶唑0．022mg／kg、磺胺(二甲)异噁唑0．037mg／kg、磺胺喹噁啉0．043mg／kg。【结论]高效液相色谱(HPLC)测定动物性食品中磺胺、喹乙醇、磺胺嘧啶、磺胺噻唑、磺胺甲嘧啶、甲氧苄啶、磺胺二甲嘧啶、呋喃唑酮、磺胺甲基异噁唑、磺胺(二甲)异噁唑、磺胺喹噁啉的多残留是一种灵敏度高、简便的方法。     

电喷雾超高效液质联用法测定动物性食品中磺胺类药残

目的:建立固相萃取-超高效液相色谱(UPLC)串联质谱法快速测定11种常用磺胺类化合物(磺胺、磺胺噻唑、磺胺吡啶、磺胺甲基嘧啶、磺胺多辛、磺胺甲二唑、磺胺间甲氧嘧啶、磺胺氯达嗪、磺胺二甲异恶唑、磺胺二甲氧嘧啶、磺胺喹恶啉的方法。方法:加入乙腈沉淀蛋白后经Waters oasis MCX固相萃取小柱净化后,使用串联四极杆电喷雾离子源正离子扫描,多反应监测(MRM)模式检测,采用Waters Acquity BEHC18分离柱(1.7μm,2.1 mm×50 mm),0.2%乙酸水溶液∶乙腈=80∶20为流动相,流速0.3 ml/min,柱温为40℃。结果:在5μg/L～200μg/L的线性范围内11种磺胺药残的定量检测下限为0.03μg/kg～0.20μg/kg,回收率能达到68.3%～108%,相对标准偏差小于10%。结论:本方法操作简单、准确、快速,灵敏度满足国际上对磺胺类药物的最低残留限量要求。     

生食水产品中7种磺胺类药物残留的液相色谱-串联质谱测定法

目的 建立生食水产品中7种磺胺类药物残留的液相色谱-串联质谱(LC-MS/MS)检测方法,包括磺胺嘧啶、磺胺甲基嘧啶、磺胺二甲嘧啶、磺胺间甲氧嘧啶、磺胺对甲氧嘧啶、磺胺噻唑、磺胺多辛.方法 试样中加入C1s填料后研磨均匀,磺胺类药物用乙腈-水在微波辐照辅助下进行提取,用乙腈饱和的正己烷液分配净化,用LC-MS/MS法测定.使用电喷雾离子化源(ESI),在正离子条件下以选择离子监测(SRM)方式进行扫描,外标法定量.结果 该法线性范围为10～100 μg/kg,以加标样品计算,在各浓度水平下各被测物的方法回收率均为70％～100％,各被测物的检出限为3μg/kg.结论 该法灵敏、快速、准确,可用于生食水产品中磺胺类药物残留的检测.     

鲜牛乳中磺胺类兽药残留监测调查

目的 了解和掌握兰州地区鲜牛乳中磺胺类兽药残留水平及其分布规律。方法 采用高效液相色谱法同时测定4种磺胺类兽药的残留量。结果 鲜(生)乳中磺胺的残留检出率为7．41％，磺胺嘧啶为4．44％，甲氧苄基嘧啶为12．59％，磺胺甲恶唑为21．48％。结论 鲜牛乳中磺胺类兽药残留问题突出，应强化监管。     

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.     

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.     

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.