高效液相色谱法测定禽肉中的己烯雌酚残留

目的:采用高效液相色谱法(HPLC)测定禽肉中的己烯雌酚残留。方法:样品经甲醇提取,ZORBAXSB-C18色谱柱分离,二极管阵列检测器检测,外标法定量。结果:己烯雌酚在0.1μg/ml～1.2μg/ml范围内线性良好(r=0.9992),且峰形对称,平均加标回收率为98%～102%,精密度RSD为2.6%～5.0%,检出限为0.05μg/ml。结论:该方法操作较快速,灵敏度高,结果准确可靠。     

固相萃取高效液相色谱法同时测定禽畜组织中雌雄性激素残留的研究

目的:固相萃取高效液相色谱法同时测定禽畜组织中已烯雌酚(DES)、丙酸睾酮(TES)的残留量。方法:固相萃取小柱为AlltechExtract-cleancolumnsC18, 200mg/4 .0ml,洗脱液为甲醇;色谱柱为SUPELCODiscoveryC18 5μm250×4 .6mm,流动相为:甲醇∶水=85∶15(v/v),流速为1 0ml/min,二极管阵列检测器,检测波长为245nm。结果:该方法的线性范围为: 0 5 ~10 0μg/ml;标准曲线线性良好,其回归方程及相关系数r分别为已烯雌酚:Y=61 .31042X+2. 38615,r=0 99999;丙酸睾酮:Y=60. 42778X-0 20465,r=0 .99994。最低检出限分别为:已烯雌酚9. 5μg/kg;丙酸睾酮8 .4μg/kg;回收率在92% ~103% 之间,相对标准偏差小于1 .3%。结论:该方法操作简便、快捷,是禽畜类食品激素残留的快速而准确的检测方法。     

反相高效液相色谱法测定佛手散醇提物中川芎嗪、阿魏酸的方法学建立

目的:建立佛手散乙醇提取物中的川芎嗪、阿魏酸方法学,为该方有效部位的药效学研究提供依据。方法:采用高效液相色谱法测定,川芎嗪及阿魏酸色谱条件分别为:甲醇-水-冰醋酸(35∶65∶0.5,v∶v∶v),柱温:25℃,检测波长:290 nm;甲醇-水-冰醋酸(27∶73∶0.5,v∶v∶v),柱温:30℃,检测波长:320 nm;计算两者方法回收率,考察精密度并进行重现性、稳定性实验。结果:川芎嗪在2μg/ml～64μg/ml线性范围内呈良好线性关系(r=0.9996),RSD为3.75%;阿魏酸在0.08μg/ml～2.56μg/ml线性范围内,线性范围内呈良好线性关系(r=0.9997),RSD为4.57%。结论:RP-HPLC对佛手散醇提物中川芎嗪、阿魏酸的测定专一性强,灵敏度高,样品较稳定,精密度和回收率好,操作简便易行,方法可靠。     

SPE-HPLC同时测定水产品中己烯雌酚、甲基睾酮的研究

目的:固相萃取高效液相色谱法同时测定水产品中己烯雌酚(DES)、甲基睾酮(MET)的残留量。方法:固相萃取小柱为AlltechExtract cleancolumnsC18,2 0 0mg/ 4.0ml,洗脱液为甲醇;色谱柱为SUPELCODiscoveryC185 μm2 5 0×4.6mm ,流动相为:甲醇∶水=75∶2 5 (V/V) ,流速为1 0ml/min ,二极管阵列检测器,检测波长为2 4 5nm。结果:该方法的线性范围为:0.5～10.0 μg/ml;标准曲线线性良好,其回归方程及相关系数r分别为己烯雌酚:y =6 1 3 10 4 2x+ 2 3 86 15 ,r =0 99994 ;甲基睾酮:y =6 6.5 5 4 2 7x + 2.3 2 4 91 ,r =0.99994。最低检出限分别为:己烯雌酚9 5 μg/kg ;甲基睾酮5 4μg/kg ;回收率在95 %～10 2 %之间,相对标准偏差小于1.3 %。结论:该方法操作简便、快捷,是水产品激素残留的快速而准确的检测方法     

高效液相色谱法测定奶粉中己烯雌酚

目的建立测定奶粉中己烯雌酚的高效液相色谱法。方法样品经甲醇超声萃取、离心,提取液浓缩后经0.45μm滤膜过滤进高效液相色谱分析。结果测定己烯雌酚的线性范围0.5~20μg/ml,相关系数r≥0.9995,平均回收率92.2%,检出限为0.06μg。结论建立的方法可准确、快速的测定奶粉中的己烯雌酚。     

红曲类保健食品中洛伐他汀检测的方法研究

目的:为准确测定红曲类保健食品中洛伐他汀的含量,对高效液相色谱法测定洛伐他汀进行了优化。方法:采用Agilent EclipseXDB-C18(5μm,4.6*250 mm)色谱柱分离;流动相为甲醇∶水∶磷酸=385∶115∶0.14(V∶V∶V);流速1.0 ml/min;检测波长238 nm测定。结果:洛伐他汀在8μg/ml～400μg/ml范围内呈现良好的线性(r=0.9999),检出限为4μg/ml,加标回收率为88.6%～93.7%,方法精密度RSD为1.68%。结论:该方法简便、快速、准确,适用于保健食品中洛伐他汀含量的测定。     

LC/MS/MS电喷雾正负离子切换同时检测动物组织中的性激素

目的:固相萃取高效液相色谱-串联质谱电喷雾正负离子切换同时测定禽畜组织中已烯雌酚(DES)、甲基睾酮(MET)、丙酸睾酮(TES)的残留量。方法:样品经甲醇提取,Alltech Extract-clean columns C18,200 mg/6 ml小柱净化和富集。通过Waters SunFireTMC183.5μm 100×2.1 mm色谱柱分离,流动相为:甲醇∶水=85∶15(V/V),ES-、ES+切换,MRM方式测定,外标法定量。结果:最低检出限分别为:已烯雌酚0.15μg/kg;甲基睾酮0.15μg/kg、丙酸睾酮0.33μg/kg;回收率在94.5%～105%之间,相对标准偏差3.2%～10.2%。结论:该方法操作简便、快捷,是动物组织激素残留的快速而准确的检测方法。     

高效液相色谱法测定辣椒粉中的碱性橙

目的:采用高效液相色谱法(HPLC)测定辣椒粉中的碱性橙。方法:称取样品于50 ml塑料离心管中,加入10 ml提取液,超声、离心后,取上清液过膜进样。采用XDB-C18色谱柱(5μm,4.6×250 mm),流动相为乙腈+乙酸铵(75+25),流速1.0 ml/min,二极管阵列检测器检测。结果:碱性橙在1.0μg/ml～50.0μg/ml范围内线性良好(r=0.9992),且峰形较好,回收率为93.4%,精密度RSD=0.61%,最低检出限为0.3μg/ml。结论:高效液相色谱法测定辣椒粉中的碱性橙,方法定性准确、灵敏度高、回收率和重现性好,操作快速,结果准确可靠。     

二极管阵列反相高效液相色谱法测定松针提取物中二氢槲皮素含量的研究

目的:建立一种采用反相高效液相色谱测定松针提取物中二氢槲皮素含量的测定方法。方法:样品中的二氢槲皮素经甲醇提取、C18反相液相色谱柱分离,在波长290 nm处检测。结果:二氢槲皮素5μg/ml～200μg/ml范围内呈良好线形,相关系数r=0.99998,检出限为0.2μg/ml。平均回收率为97.1%,RSD为1.0%～1.2%。结论:本方法操作简单,准确可靠,可用于检测松针提取物保健食品中的二氢槲皮素含量。     

固相萃取-高效液相色谱法测定畜禽肉中四环素类抗生素残留

目的:建立采用固相萃取技术净化样品,高效液相色谱-紫外检测器同时测定畜禽肉中土霉素、四环素和金霉素3种四环素类抗生素残留的方法。方法:样品经过匀浆、旋涡、超声、离心后,取上清液经Wa-ters Oasis HLB萃取柱净化,净化液经氮吹仪浓缩后进样,色谱柱采用Agilent Eclipse XDB-C18 150×4.6 mm,5μm,流动相为(0.01 mol/L磷酸二氢钠∶乙腈∶甲醇=70∶20∶10,流速0.8 ml/min,检测波长为355 nm和270 nm,柱温30℃,进样量50μl进行检测。结果:样品平均回收率为82.0%～98.4%,RSD为0.8%～3.2%,线性范围为0.02μg/ml～10μg/ml,相关系数为0.99998～0.99999,最低检出浓度为土霉素0.4μg/kg,四环素0.4μg/kg,金霉素0.8μg/kg。结论:建立的方法用于同时测定畜禽肉中土霉素、四环素和金霉素3种四环素类抗生素残留灵敏度高,分离度好,回收率高,适合于日常检测工作。     

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 human drama of genetics: 'hard' and 'soft' media representations of inherited breast cancer

This paper examines media coverage of 'breast cancer genetics', and explores its implications for public understanding. We present a content analysis of coverage in British newspapers and look at a variety of popular forms, including women's magazines, television soap opera and radio drama. Genetic/inherited risk receives a great deal of coverage across a wide range of media formats and outlets. Much of this attention has focused on individuals from 'high risk families' and dilemmas around prophylactic mastectomies. Through examining media coverage, combined with interviews with media personnel and their sources, we show why this story proved so attractive to the media and highlight the different production values which influence coverage. Finally, we introduce preliminary findings from focus group discussions to demonstrate how such 'human interest' framing has engaged audience attention and influenced public understandings. The paper concludes by highlighting the implications for analysing, predicting, and engaging with, media representations of science.     

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.     

Worker education in the primary prevention of occupational dermatoses

This paper reports the evaluation of a skin care education programmeconducted on a fine chemicals manufacturing site where over1,000 employees are located. Approximately 60% are involvedin chemical manufacture. Over a 12 month period production staffreceived training in prevention of occupational dermatoses linkedto a site-wide poster initiative. The incidence of new casesof occupational dermatoses fell from 0.055 (70 cases in 1,277employees) to 0.021 (27 cases in 1,277 employees) before andafter the intervention respectively (p<0.0001). After otherfactors such as chemicals handled, observer bias and changesin reporting related to socioeconomic climate were taken intoaccount it is concluded that this study demonstrates the importanceof worker education as a tool for primary prevention of disease.Training materials such as video and poster presentations maybe effectively used in the chemical manufacturing industry asan adjunct to prevention and control of exposure to substanceshazardous to the skin. Such methods may also be used in otherindustries where there are significant risks of dermatoses.     

Regional Variation in Travel-related Illness acquired in Africa,March 1997–May 2011

To understand geographic variation in travel-related illness acquired in distinct African regions, we used the GeoSentinel Surveillance Network database to analyze records for 16,893 ill travelers returning from Africa over a 14-year period. Travelers to northern Africa most commonly reported gastrointestinal illnesses and dog bites. Febrile illnesses were more common in travelers returning from sub-Saharan countries. Eleven travelers died, 9 of malaria; these deaths occurred mainly among male business travelers to sub-Saharan Africa. The profile of illness varied substantially by region: malaria predominated in travelers returning from Central and Western Africa; schistosomiasis, strongyloidiasis, and dengue from Eastern and Western Africa; and loaisis from Central Africa. There were few reports of vaccine-preventable infections, HIV infection, and tuberculosis. Geographic profiling of illness acquired during travel to Africa guides targeted pretravel advice, expedites diagnosis in ill returning travelers, and may influence destination choices in tourism.     

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.     

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.