一氧化氮在镉致急性肝损伤中的作用及慈菇的干预效果

目的：探讨NO在镉致急性肝损伤中的作用以及慈菇的干预效果，方法：30只雄性SD大鼠随机分为5组，每组6只，分别用25％，50％，75％的慈菇（2ml/100g体重）及等体积蒸馏水灌胃10天，未次灌胃24h后，腹腔注射CdCl2(20umol/L/kg体重）或蒸馏水，染毒24h后，观察血清NO含量、GPT、LDH活力及肝组织NOS活力，MDA合量，结果：CdCl2组与阴性对照组比较，血清LDH，GPT活力，肝组织MDA合量显升高（P＜0．05），中、高浓度慈菇干预组相比CdCl2组LDH，GPT活力及MDA含量显降低（P＜0．05），血清中NO含量及肝组织NOS活性各组间无明显差异（P＞0．05），不同浓度慈菇对肝组织，NOS活性及血清NO浓度的降低具有剂量反应关系（r分别为－0．9596，－0．9956，P＜0．05）；结论：NO可能参与镉所致肝脏的急性过氧化损伤，提示慈菇对镉致肝急性损伤具有保护作用。     

依布哂啉和谷胱甘肽对大鼠过氧化抑制作用

目的 探索依布硒啉（Ebs）和谷胱甘肽（GSH）对酒精依赖大鼠过氧化损伤的抑制作用和效果。方法 测定第3周末酒精依赖大鼠血清中的谷胱甘肽过氧化物酶（GPx）活性和脂质过氧化物丙二醛（MDA）生成量，以GPx与MDA比值反映过氧化抑制作用。将服药组的GPx与MDA比值减去阳性组GPx与MDA比值除以服药组GPx与MDA比值的百分率，得出抑制效率。结果 Ebs0．1～10mg/kg与GSH5～10mg／kg联合作用的过氧化抑制效率在40．0％～65．7％之间（P均〈0．01），显示剂量与功效关系（r=0．693，P〈0．01）。Ebs5～10mg／kg的抑制效率为36．7％～45．3％。结论 酒精过氧化损伤时的Ebs抗氧化作用除依赖辅助因子GSH外，还可能通过其他途径产生。     

有机锗-132对乙醇中毒所致大鼠肝脏损伤的保护作用

目的:探讨有机锗-132对乙醇依赖所致大鼠肝损伤的拮抗作用。方法:用市售北京红星牌二锅头(含52%酒精),按5.0g/kg体重剂量连续3个月灌胃形成大鼠酒精依赖,同时给予有机锗-132,观察大鼠肝脏损伤情况,并检测血谷丙转氨酶(GPT)活性、肝组织中脂质过氧化物终末产物丙二醛(MDA)的含量变化及超氧化物歧化酶(SOD)、黄嘌呤氧化酶(XOD)和过氧化氢酶(CAT)的活性。结果:给大鼠喂饲乙醇三个月,其肝组织中的丙二醛含量与对照组比较明显升高(P<0.01),抗氧化酶SOD和CAT活性明显降低(P<0.05),XOD活性明显升高(P<0.01);酒中加锗-132能明显降低肝组织中的丙二醛含量,SOD、CAT及XOD活性亦有所恢复。结论:有机锗-132对乙醇中毒所致大鼠肝脏损伤有一定的保护作用。     

人参低聚肽对急性酒精性肝损伤大鼠的保护作用

目的 探讨人参低聚肽（GOP）对酒精诱导的大鼠急性肝损伤的保护作用及其可能机制。方法 采用SPF级SD雄性大鼠,随机分为7组,每组10只,包括,1个空白对照组、1个模型对照组、1个乳清蛋白对照组（0.250 0 g/kg）和4个GOP剂量组(0.062 5、0.125 0、0.250 0、0.500 0 g/kg)。连续灌胃30d后,采用体积分数 50%的酒精以 7g/(kg·BW)剂量灌胃造成大鼠急性酒精性肝损伤模型,测定大鼠血清ALT、AST活性和肝脏SOD、GSH、GSH-PX及MDA含量。结果 与模型对照组相比,GOP干预可以显著降低大鼠血清ALT、AST和肝组织MDA(P<0.05或P<0.01)的水平,增加肝组织SOD 、GSH和GSH-PX的活性（P<0.05或P<0.01)。结论 GOP对酒精诱导引起的大鼠急性肝损伤具有保护作用,其机制可能与提高机体抗氧化水平有关。     

新云三七对化学性肝损伤保护作用的功能评价

目的：评价新云三七速溶粉对大鼠化学性肝损伤的保护作用。方法：按《保健食品功能评价程序和检验方法》，将雄性Wistar大鼠随机分为三个受试物剂量组（1.25g/kg、3.75g/kg和7.5g/kg)及肝损伤模型对照组、阴性对照组进行试验，连续30日按2％（v/w)灌胃给予受试物后，测定血生化指标，进行肝组织病理切片检查并辅以酶组织化学检查。结果：高剂量组动物血清ALT水平较模型对照组显著降低（P＜0．05），肝细胞坏死较模型对照组明显减轻（P＜0．05），膜酶5－N'、ATPase、SDH、NADPH活性均较模型对照组高（P＜0．05）。结论：新云三七速溶粉对四氯化碳所致大鼠肝组织损伤具有一定辅助保护作用。     

慈菇对镉致急性肝脏过氧化损伤影响的研究

目的 探讨慈菇对镉致大鼠急性肝损伤的保护作用及其机制。方法　36只雄性SD大鼠随机分为6组（n=6）,分别用25％、50％、75％的慈菇（2ml/100g体重）,维生素E（50mg/100g体重）及等量的蒸馏水灌胃,连续10天,末次灌胃24h后,腹腔注射CdCl2（20μmol/kg体重）,染毒24h后,比较各组血清乳酸脱氢酶（LDH）、谷丙转氨酶（GPT）活性,肝组织谷胱甘肽（GSH）、丙二醛（MDA）、镉（Cd）含量及超氧化物歧化酶（SOD）、谷胱苷肽过氧化物酶（GSH-PX）活性。结果 中、高浓度慈菇均能降低血清LDH、GPT活性（P<0.05）,降低肝组织MDA含量（P<0.05）,提高肝组织GSH含量（P<0.05）;高浓度慈菇组还降低了肝组织镉含量（P<0.05）;而VE仅降低了肝组织MDA含量（P<0.05）。结论 预先给予慈菇对镉致大鼠的急性肝损伤具有一定保护作用,且效果优于VE,其机制可能是同时增强了抗氧化和解毒的两个过程。     

ROS指标在保健食品抗氧化功能检测中的应用及灵敏性比较

目的：将ROS指标应用于保健食品抗氧化功能检测中，并进行敏感性比较。方法：SPF级昆明种雄性小鼠，12月龄，按体重随机分为老龄组对照组、大豆异黄酮低、中、高剂量组（分别为0．08g／kgBW、0．17g／kgBW、0．50g／kgBW），每组10只动物。连续灌胃给予受试物42d后，断头处死动物，取肝脏。以胶原酶和胰蛋白酶联合酶解肝组织，制备肝组织单细胞悬液；以流式细胞术测定肝细胞ROS水平；同时制备肝组织匀浆，以分光光度法测定肝细胞MBA含量及SOD、GSH—Px活性。结果：流式仪直方图分析显示，随着受试物给予剂量的增加，各剂量组肝细胞ROS水平均明显降低（P〈0．05）；低、高剂量组肝细胞内MDA含量明显减少（P〈0．05），中、高剂量组GSH—Px活性明显增加（P〈0．05），高剂量组,SOD活性亦明显增加（P〈0．05）；其余剂量组各指标差异无统计学意义（P〉0．05）。结论：大豆异黄酮通过降低肝细胞自由基水平而起到抗氧化作用，以FCM检测肝细胞ROS水平可更好地对保健食品的抗氧化功能进行筛选与评价。     

硒对大鼠肝脏抗氧化酶活性及基因表达的影响

目的：探讨补硒对大鼠肝脏抗氧化酶活性及基因表达的影响。方法：给大鼠补充不同剂量的硒，观察补硒对大鼠肝脏硒、丙二醛（MDA）含量，超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GSH－Px）、硫氧还蛋白还原酶（TR）活性及TR mRNA表达的影响。结果：补硒20μg/kg能显著降低MDA含量，增强SOD、CAT、GSH－Px的活性，而补硒40，80μg/kg却显著增加MDA含量，降低CAT、GSH－Px和TR的活性，并能降低TR mRNA表达水平。硒的含量则表现出剂量依赖性。结论：硒对机体有双重作用，适当剂量硒增强机体抗氧化功能，过高剂量硒使机体中毒。     

二月桂酸二丁基锡对大鼠肝脏毒性作用

目的用二月桂酸二丁基锡（DBTD）染毒大鼠，探讨DBTD对大鼠肝脏及血清中酶活性的影响。方法选踺康成年大鼠28只。随机分为0，5，10，20mg／kg4个剂量组，每组7只动物，用DBTD灌胃染毒5周后处死动物，测定血清中碱性磷酸酶（ALP）、谷丙转氨酶（GPT）、γ-谷氨酰基转移酶（GGT）、肝组织中酸性磷酸酶（ACP）、碱性磷酸酶（AKP）、乳酸脱氢酶（LDH）活性及肝脏中锡含量。结果各剂量组大鼠肝脏中锡含量，肝组织中ACP、AKP、LDH。血清中ALP、GGT、GPT活性明显高于对照组（P〈0．01，P〈0．05）。结论DBTD可在肝组织中蓄积，具有肝毒性．可影响忏审酶的活幛两阡的下皆曲能     

硒对酒精引起肝损伤的拮抗作用研究

目的 探讨硒对酒精中毒所致大鼠肝损伤的拮抗作用。方法 给大鼠喂饲精饲料中加硒，观察大鼠肝脏损伤情况，并检测脂质过氧化物终末产物丙二醛（MDA）的含量变化及超氧化物歧化酶（SOD）、黄嘌呤氧化酶（XOD）和过氧化氢酶（CAT）的活性。结果 给大鼠喂饲酒精3个月，其肝组织中的丙二醛含量与对照组比较明显升高（P＜0．01），抗氧化酶SOD和CAT活性明显降低（P＜0．05），XOD活性明显升高（P＜0．01）；酒中加硒能明显降低肝组织中的丙二醛含量，SOD、CAT及XOD活性亦有所恢复。结论 硒对酒精中毒所致大鼠肝脏损伤有一定的保护作用。     

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.