超声辅助乳化液液微萃取-高效液相色谱法测定水中邻苯二甲酸酯

目的:将超声辅助萃取与液液微萃取技术结合,建立水中邻苯二甲酸酯的高效液相色谱测定方法。方法:对水样的超声萃取条件和液液微萃取条件进行优化,采用高效液相色谱测定。结果:在0μg/ml～6.0μg/ml范围内线性关系良好r,>0.999;三种邻苯二甲酸酯检出限为0.2μg/L;水样中加标回收率为88.4%～105.4%,相对标准偏差在3.1%～6.8%。结论:本方法快速、准确适用于水中邻苯二甲酸酯的浓度测定。     

化妆品中二苯酮-2和二苯酮-3的高效液相色谱测定法

目的建立化妆品中二苯酮-2和二苯酮-3的高效液相色谱测定方法。方法样品经乙腈-水超声处理,采用高效液相色谱法进行检测。利用Phenomenex GEMINI C18110A(250 mm×4.6 mm,5μm)色谱柱,以乙腈-水作为流动相,流量:1.0 ml/min,检测波长:335 nm,柱温:30℃。结果二苯酮-2和二苯酮-3的线性范围均为1～150μg/ml,相关系数均大于0.999,检出限均为0.15μg/ml,定量限均为1μg/ml,回收率均在90%～100%之间,相对标准偏差均不超过2.0%。结论本法操作简便,准确,可同时测定不含蜡质的化妆品中二苯酮-2和二苯酮-3的含量。     

固相萃取-高效液相色谱测定水中5种磺酰脲类除草剂

[目的]本文建立了同时测定水中5种磺酰脲类除草剂的固相萃取-高效液相色谱分析方法.[方法]水样中5种除草剂(甲磺隆、氯磺隆、苄嘧磺隆、苯磺隆、吡嘧磺隆)的残留经C18固相萃取小柱萃取,采用高效液相色谱法,用C18色谱柱分离,以乙腈:0.001mol/L盐酸(55:45,v/v)为流动相,等度洗脱,紫外检测器在波长为230nm处测定.[结果]对样品前处理和色谱分离条件进行了优化,5种除草剂的质量浓度在0.05～2.00mg/L范围内其浓度与峰面积呈良好的线性关系(r=0.998～0.9999).自来水与河水样品的加标平均回收率为73.0%～99.4%,相对标准偏差(RSD)为1.45%～4.15%;对于100.0ml水样,本方法的检出限为0.30～0.70μg/L.[结论]本法简便、快速、准确、灵敏度高,能满足环境水样中5种磺酰脲类除草剂残留分析要求.     

HPLC法同时测定保健品中腺苷和虫草素含量的研究

目的:建立保健品中腺苷和虫草素含量的测定方法。方法:样品用水超声提取,反相高效液相法同时测定腺苷和虫草素两种成分。色谱条件为:Diamonsil C18色谱柱(150 mm×4.6 mm,5μm),乙腈-水为流动相(6:94,V/V),检测波长为260 nm。结果:腺苷和虫草素在1.0～100.0μg/m l范围内线性良好,回收率为95.2%～99.1%,相对标准偏差为1.10%～3.05%,检测限均为0.1μg/ml。结论:本法简便、准确,可同时测定保健品中的腺苷和虫草素。     

毛细管气相色谱法测定水中2,4,6-三氯酚和五氯酚

目的:建立测定水中2,4,6-三氯酚和五氯酚的气相色谱测定方法。方法:水中的微量2,4,6-三氯酚和五氯酚经液-液萃取后,用DB-1701毛细管色谱柱,在程序升温条件下进行GC分析,以保留时间定性,外标法定量。结果:2,4,6-三氯酚的线性范围为0.005μg/L~1.0μg/L,最低检出浓度为0.0030μg/L,五氯酚的线性范围为0.01μg/L~2.0μg/L,最低检出浓度为0.0048μg/L,相关系数均≥0.9990,水样加标回收率为73.0%~91.0%,RSD为4.6%~7.9%。结论:方法仅用8.5 m in完成饮用水中2,4,6-三氯酚和五氯酚的测定,操作简便、灵敏度高。     

分散液-液微萃取-气质联用法同时测定水中13种三唑类杀菌剂

目的:建立分散液-液微萃取-气相色谱串联质谱法同时测定水中13种三唑类杀菌剂。方法:水样中加入50μl四氯化碳(萃取剂)和1.0 ml丙酮(分散剂),0.1 g氯化钠,分散混匀后,以5000 rpm/min离心5 min,吸取四氯化碳层进样,以气相色谱-串联质谱多反应监测(MRM)模式定量测定。结果:13种三唑类杀菌剂农药的富集倍数达81倍～785倍。在0.5μg/L～500μg/L范围内具有良好的线性关系,线性相关系数为0.9990～0.9999;回收率为72.0%～128.0%,相对标准偏差(RSD)为2.1%～6.6%,定量限为0.0015μg/L～0.25μg/L。结论:本法具有操作简单、富集效率高和灵敏度高等特点,可满足水样中13种三唑类杀菌剂农药残留同时检测要求。     

HPLC法测定人血浆中莫西沙星的浓度

目的建立一个高效液相-荧光色谱方法测定患者血浆中莫西沙星的浓度,为临床研究提供分析方法。方法临床血透患者血样经过液液萃取处理后,采用高效液相-荧光测定;色谱柱:依利特SinoChromODS-BP(5μm,4.6 mm×150 mm);流动相为乙腈:缓冲液(25∶75),缓冲液为每1 000 ml水溶液中含有磷酸二氢钾10 mmol和四丁基硫酸氢胺1.5 mmol;流速:1 ml/min;柱温:40℃;激发波长为290 nm;发射波长为488 nm。进样体积:10μl。结果血浆中莫西沙星浓度在0.1～10.0 mg/L范围呈良好的线性关系(r=0.9999),定量下限浓度为0.1 mg/L,准确性平均为97%,RSD为8.7%;绝对回收率大于78%;批内RSD为1.12%～2.08%、批间RSD为3.2%～5.7%,方法回收率在91.0%～101.3%之间。结论本分析方法具有快速、灵敏、准确、可靠,适用于临床药理研究及药动学分析。     

高效液相色谱-串联质谱法同时测定饮用水中的13种农药残留

目的建立饮用水中的灭草松、甲基对硫磷、乐果、2,4-滴、多菌灵、呋喃丹、莠去津、敌敌畏、毒死蜱、丁草胺、甲草胺和乙草胺等13种农药残留的高效液相色谱-串联质谱(HPLC-MS/MS)同时测定方法。方法水样经0.22μm滤膜过滤后直接进样,采用液相色谱-串联质谱仪进行测定,色谱柱采用Accucore C18(100 mm×2.1 mm,2.6μm),以乙腈-水-甲酸为流动相,梯度洗脱。采用电喷雾电离(ESI),多反应监测(MRM)模式进行检测。结果本法测定的线性范围为0.50 ng/ml~100.00 ng/ml,线性相关系数(r)为0.998 8~1.000 0,检出限为0.001 ng/ml~0.250 ng/ml。在低、中、高3种添加浓度下,方法的平均回收率为81.0%~119.0%,相对标准偏差(RSD)为0.54%~11.00%。结论本法操作简单,准确、快速、灵敏,能满足日常大批量水样中多种农药残留的快速准确分析。     

高效液相色谱法测定作业场所中4,6-二硝基邻苯甲酚

目的:测定工作作业场所中4,6-二硝基邻苯甲酚。方法:高效液相色谱法。结果:含量在0.20~1.00μg/m l时,相关系数r=0.9990,具有良好的线性关系,其回归方程Y=1.98×105X-1.25×104,相对标准偏差RSD为0.66%~8.17%,加标回收率为88.20%~97.88%。方法检测限为0.2μg/m l,最低检出浓度为0.067 mg/m3。结论:本法操作简便、快速、灵敏、分析结果可靠。     

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.