高效液相色谱法快速检测水中5种拟除虫菊酯残留量

目的建立反相高效液相色谱法测定水中5种拟除虫菊酯残留量的方法。方法样品经过滤后进行反相高效液相色谱测定,色谱柱Waters Symmetry C185μm,4.6mm×250mm,流动相为乙腈∶水=78∶22（V/V）,流速1.0mL/min,二极管阵列检测器,检测波长205nm。结果 5种拟除虫菊酯类农药分离良好,在0.050~5.0mg/L范围内有良好线性关系,检出限分别为：甲氰菊酯2.5μg/L、氯氟氰菊酯3.0μg/L、溴氰菊酯3.0μg/L、氰戊菊酯3.0μg/L、氯菊酯5.0μg/L;回收率在95.2%~98.4%。结论该法操作简便快捷、方法稳定性好,适用于水中拟除虫菊酯农药残留的快速检测。     

水中孔雀石绿的高效液相色谱测定法

目的 建立淡水中孔雀石绿含量的高效液相色谱法测定分析方法.方法 采用ZORBAX SB-C18(250 mm×4.6 mm,5μm)色谱柱,二氧化铅柱后氧化柱,流动相为0.1 mol/L(pH=4.5)的乙酸铵溶液:乙腈(体积比为20:80),流速为1.5 ml/min,紫外检测器波长为588 nm.结果 该方法在孔雀石绿浓度范围在0.1～4.0μg/ml时,r=0.999 72.以峰面积(x)对质量浓度(y)做标准曲线,得到线性方程为:y=40.25 x 1.99.根据3倍信噪比计算,最低检测限为0.02μg/L.向不含孔雀石绿的水样中分别加入2.0、10.0μg/L的孔雀石绿溶液进行高效液相色谱法的精密度、准确度试验,结果显示,平均回收率分别为98.5%,97.8%,RSD分别为11.2%,8.0%.结论 本方法操作简单,回收率稳定,灵敏度高,适用于淡水中的孔雀石绿含量的检测,但不适用于无色孔雀石绿的检测.     

固相萃取高效液相色谱法检测水中二苯胺残留量

目的:建立固相萃取高效液相色谱法测定水中二苯胺残留量的方法。方法:样品经固相萃取后进行高效液相色谱测定。色谱柱为SUPELCO Discovery C185μm 250×4.6 mm,流动相为:甲醇:0.02 mol/L NH4AC(pH=4.2)=70:30(V/V),流速为0.8 ml/min,二极管阵列检测器,检测波长为280 nm。结果:该方法的线性范围为:0.050～10.0μg/ml;标准曲线线性良好,其回归方程及相关系数r为Y=348.4X-3.5,r=0.99999。检出限为:0.60μg/L;回收率在99%～103%之间,相对标准偏差小于2.0%。结论:该方法操作简便、快捷,是水中二苯胺残留量的快速而准确的检测方法。     

反相高效液相色谱法测定蒲地蓝消炎口服液中绿原酸和咖啡酸的含量

目的建立同时测定蒲地蓝消炎口服液中绿原酸和咖啡酸含量的反相高效液相色谱法。方法采用反相高效液相色谱法,色谱柱为岛津Inertsil ODS C18柱(4.6 mm×250 mm,5μm),流动相为乙腈-0.04%磷酸水溶液(15∶85,V/V),流速为1.0 ml/min,柱温为35℃,检测波长为327 nm。结果绿原酸与咖啡酸的质量浓度为4.0 g/ml~19.0 g/ml时,与峰面积呈良好的线性关系,线性回归方程分别为y=37 434.0x-45 435.1(r=0.999 6)、y=111 260x-152 136(r=0.999 8)。绿原酸与咖啡酸的平均回收率分别为99.0%(RSD=1.65%)和100.1%(RSD=1.78%)。结论方法简便、快速、准确,可用于蒲地蓝消炎口服液中绿原酸和咖啡酸含量的同时测定。     

反相高效液相色谱法测定饮用水中溴氰菊酯残留

目的:建立反相高效液相色谱法检测饮用水中溴氰菊酯残留.方法:萃取两次后浓缩测定.采用Gemini C18柱,以甲醇 水=95 5为流动相进行分离,紫外检测器检测,外标法定量.结果:溴氰菊酯浓度在0～12 μg/ml范围内线性关系良好,相关系数r=0.999,最低检测浓度为0.004 mg/L.平均回收率在95.1%～99.4%范围内,相对标准偏差为1.64%2.42%.结论:方法灵敏度高,实用性强,适合广大基层检测单位日常工作中水中溴氰菊酯含量的检测.     

水中灭蝇胺的高效液相色谱测定法

目的 建立水源水中灭蝇胺残留量的高效液相色谱法测定法.方法 色谱柱为YMC C18(150 mmx4.6 mm,5 μm),流动相为甲醇 0.02 mol/L NH4AC=15 85(V/V),流量为1.0 ml/min,二极管阵列检测器,检测波长为210 nm.结果 该方法的线性范围为0.050～10.0 μg/ml;标准曲线回归方程为y=243.8x-4.2,相关系数r=0.999 96.检出限为0.010 mg/L;回收率为94%～100%,RSD小于3.0%.结论 该方法操作简便、快捷,是饮用水源水中灭蝇胺残留的快速而准确的检测方法.     

反相高效液相色谱法检测水中五种拟除虫菊酯农药残留量

目的:建立反相高效液相色谱法测定水中五种拟除虫菊酯残留量的方法。方法:样品经过滤后进行反相高效液相色谱测定。色谱柱为W elch M aterials AQ-C185μm 250×4.6 mm,流动相为∶乙腈∶水=78∶22(V/V),流速为1.0 m l/m in,二极管阵列检测器,检测波长为205 nm。结果:各组分分离良好,在0.050μg/m l~5.0μg/m l范围内具有良好的线性关系,其回收率在98%~102%之间。结论:该方法操作简便、快捷、可靠,可用于水中拟除虫菊酯农药残留量的检测。     

蔬菜中百草枯的高效液相色谱测定法

目的建立蔬菜中百草枯残留量的高效液相色谱-紫外检测器测定方法。方法选用AgilentTC-C18色谱柱(4.6×250mm,5μm),检测波长257nm,以10mmol/L庚烷磺酸钠(用磷酸调pH=3.0)-甲醇(50+50)作为流动相,柱流量1.0ml/min,采用高效液相色谱法检测蔬菜中百草枯含量。结果该方法的线性范围为0.00～10.0μg/ml,R2=0.9994,RSD为0.75%～3.65%,回收率为96.1%～104.0%,检出限为0.03μg/ml。结论该方法简单、快速、准确度高,适用于蔬菜中百草枯残留量的测定。     

二极管阵列反相高效液相色谱法测定蜜饯中香兰素含量

目的:建立二极管阵列反相高效液相色谱法测定蜜饯中香兰素含量的方法。方法:称取均质蜜饯样品到烧杯中,加入蒸馏水8,0℃水浴浸泡30 min,取出冷却至室温,转移到容量瓶中定容过滤,滤液待进样。采用XDB-C18色谱柱(5μm4,.6μm×150 mm),流动相为甲醇+乙酸铵(40+60v,/v),流速1.0 ml/min,二极管阵列检测器检测。结果:香兰素浓度在1.0μg/ml～30.0μg/ml范围内线性良好(r=0.9999,n=4),且峰形较好,回收率为102%,精密度RSD=2.3%;最低检出限为0.15μg/ml(以进量浓度计)。结论:二极管阵列反相高效液相色谱法测定蜜饯中香兰素含量的方法,定性准确、灵敏度高、回收率和重现性良好,操作快速,结果准确可靠。     

RP-HPLC法测定浓维磷糖浆中咖啡因和维生素B1的含量

目的:采用反相高效液相色谱法测定浓维磷糖浆中咖啡因和维生素B1的含量。方法:采用Dia-monsil C18柱(250 mm×4.6 mm,5μm),以甲醇-庚烷磺酸钠缓冲液为流动相(10∶90),检测波长为272 nm。结果:咖啡因与维生素B1浓度分别在3.5μg/ml～282.6μg/ml(r=1.0000)和0.7μg/ml～54.7μg/ml(r=0.9999)内与峰面积呈良好的线性关系(n=9),方法回收率(n=9)分别为99.2%和99.1%,RSD分别为1.8%和1.7%。结论:该方法操作简便,结果准确可靠,可以有效地控制产品质量。     

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.     

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.     

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.     

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.     

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.     

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.