黄磷与四氯化碳亚急性肝损害的机理

本文研究黄磷与CCl_4引起亚急性肝损害时,肝脏发生脂质过氧化的情况、部位及其与肝损害之间的关系。黄磷与CCl_4对大鼠亚急性中毒时,肝MDA 含量显著升高,Schiff 碱荧光强度明显增强;肝线粒体与微粒体MDA含量显著升高,且各自标志酶SDHase 活性与G-6-Pase 活性均显著降低;肝损害指标:肝TG 含量升高对两种毒物均敏感;而肝GSH 含量降低与血清SGPT 酶活性升高对两种毒物的敏感性有一定的差异。     

氯乙烯染毒大鼠代谢酶活性的动态变化和肝损伤

目的　研究氯乙烯 (VCM)染毒大鼠代谢酶活性和肝损伤生化指标的动态变化 ,以及大鼠肝脏的病理改变 ,探索血清、肝组织VCM代谢酶活性变化与肝脏损伤间的关系。方法　大鼠染毒 12周 ,分别在第 3、6、9和 12周处死动物 ,代谢酶活性测定采用分光光度法 ;肝功能生化指标用自动生化分析仪测定 ;光镜、电镜检测染毒大鼠肝组织病理改变。结果　VCM代谢酶ALDH、CYP2E1和GSTs活性随染毒时间和剂量的增加发生改变 ,差异具有统计学意义。ALP与血清ADH的活性呈负相关 (r=- 0 6 4 9) ;血清GSTs、ADH的活性分别与肝组织中GSTs、ADH活性呈正相关 (r- =0 4 39、0 5 0 8,P <0 0 5 )。结论　VCM致肝损伤程度可能与代谢酶活性有关 ,肝脏代谢酶变化是VCM引起机体损害的早期较敏感指标。     

喂饲三唑磷6个月对大鼠效应生物标志物的影响

[目的]探讨大鼠6个月摄入有机磷杀虫剂三唑磷(Hoe 02960)对效应生物标志物的影响.[方法]用含三唑磷0(对照组)、3、100mg/kg饲料喂饲SD大鼠连续6个月,3个剂量组每组动物20只,雌雄各半.于染毒前和染毒后第2、4、6、26周分别取大鼠的血液分析全血胆碱酯酶(BChE)、血浆胆碱酯酶(PChE)和红细胞胆碱酯酶(EChE)活性;于第26周分别取大鼠的尿和血,作尿和血常规及生化指标测定,同时进行动物肝、脾等脏器的病理检查.[结果]各剂量组大鼠6个月内均无死亡,体重增重、脏器系数均无明显差异.2周时100mg/kg剂量组BChE活性显著降低;4周时3、100mg/kg剂量组活性降低(P<0.05,P<0.01);6周时100mg/kg剂量组活性降低有显著性.各剂量组 BChE抑制率在第四周最高,雌鼠100 mg/kg抑制率达到21.8%,其他各剂量组抑制率均<20%,BChE活性在第六周开始逐渐回复,PChE情况与 BChE相似.各剂量组EChE抑制率随摄食时间增加而升高,至26周时 3、100 mg/kg 剂量组活性降低有显著性,3 mg/kg雄、雌大鼠抑制率分别为 5.6%和 6.0%;100 mg/kg雄、雌大鼠抑制率分别为10.6%和 11.4%,血液碱性磷酸酶(AKP)活性明显升高,RBC和Hb明显降低.病理组织学检查发现100 mg/kg剂量组肝脏肝细胞浊肿及空泡变性;脾有淤血、见色素沉着.[结论]BChE、PChE活性在喂饲早期(2～6周)可考虑作为三唑磷接触生物标志物;RBC、Hb和AKP活性在6个月接触三唑磷后可作为胆碱酯酶平行标志物;在6个月接触三唑磷过程中EChE活性虽有一定改变,但能否作为效应标志物,尚需作进一步跟踪确认.     

四氯化碳中毒性肝损害诊断指标探讨

本文以CCl_4制备大鼠和小鼠的急性和亚急性中毒性肝损害模型,观察多项血清和肝MFO指标的变化,探讨各指标的诊断价值。结果以血清甘胆酸(SGCA)和肝苯胺羟化酶指标较为理想,SGPT也是一项较为敏感的指标。     

TNT及Ccl4中毒性肝损害的自身免疫机制初步探讨

本文分别给两组供体大鼠腹腔注射TNT和CCl_4,取其分离的脾淋巴细胞和提取的肝抗原,分别转移给受体大鼠,用生化、免疫、病理等9项指标测试了转移后的毒性。结果见各组均未测到自身抗体,TNT肝抗原和脾淋巴细胞受体组的GPT活性及SIgA含量均增高,脾淋巴细胞受体组的铜蓝蛋白亦增高,而CCl_4受体组仅血清甘胆酸含量稍增。经转移后各组的病理改变均不明显。     

茵陈蒿汤对代谢综合征-脂肪肝大鼠增强胰岛素敏感性及抗脂肪肝作用

目的观察茵陈蒿汤(capillaris decoction)对高脂-高糖诱导代谢综合征(metabolic syndrome,MetS)-脂肪肝(fattyliver,FL)大鼠的防治作用及机制。方法 SD大鼠,雌雄各半,除空白对照组食用标准饲料和饮用蒸馏水外,其余动物随机喂饲富含高脂肪(25%)饲料和高蔗糖(10%)饮水,造模8周;然后将大鼠随机分为模型对照、silibinin150mg.kg-1以及茵陈蒿汤5.0g.kg-1及2.5g.kg-1两个剂量组;分别灌胃给药或蒸馏水,qd×4w,测定大鼠空腹血清胰岛素(Fins)、血糖(FBG)、三酰甘油(TG)、胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、游离脂肪酸(FFA)、脂联素,天门冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)、胆碱酯酶(ChE)、超氧化物歧化酶(SOD)、丙二醛(MDA)、一氧化氮合酶(NOS)和一氧化氮(NO),并计算胰岛素敏感指数(ISI)、胰岛素抵抗指数(IRI)及肝指数;光学显微镜下观察肝脏组织的病理学改变。结果 MetS-FL大鼠TC、FFA、TG、LDL-C、MDA、FBG和Fins含量升高,HDL-C、NO和脂联素含量下降,AST、ALT、ChE活性升高,NOS和SOD活性降低,ISI减弱,肝指数升高并呈脂肪肝组织病理改变,与正常对照组比较,差异有显著性(P<0.05或P<0.01)。茵陈蒿汤5.0g.kg-1及2.5g.kg-1以及silibinin150mg.kg-1处理MetS-FL大鼠后,不同程度地降低MetS-FL大鼠TC、FFA、TG、LDL-C、MDA、FBG、Fins含量和AST、ALT、ChE活性,升高HDL-C、NO和脂联素含量,增强ISI,肝指数下降并改善脂肪肝组织病理改变,差异有显著性(P<0.05或P<0.01)。结论茵陈蒿汤对抗MetS-FL大鼠IR、增强胰岛素敏感性、纠正高胰岛素血症,改善血糖-脂代谢紊乱,抑制氧化应激反应和肝细胞损伤,降低氨基转移酶和ChE活性,以及不同程度地改善脂肪肝组织的病理改变,是茵陈蒿汤拮抗代谢综合征-脂肪肝的部分作用机制。茵陈蒿汤抗脂肪肝效应显示量效关系。     

喹胺酸对急性铍中毒大鼠肝功能的保护作用

49只Wistar大鼠分成4组:对照组、中毒组、治疗组Ⅰ(治疗1天)和治疗Ⅱ(治疗3天)。大鼠由静脉注入BeSO_4·4H_2O 7.50mg/kg,即刻由腹腔注入喹胺酸500mg/kg者为治疗组;腹腔注入生理盐水者为中毒组。对照组均注射生理盐水。结果如下:对照组SGPT40u/L左右渡动,尿铍、肝铍和肾镀均阴性。中毒组于染毒后第三天尿铍总排泄量为染毒量的9.3%,此时SGPT活性高达1600u/L;肝铍含量29.1μg。而同时期治疗组Ⅰ和Ⅱ尿铍总排出量分别为25.4%和27.0%;SGPT活性分别为60u/L和52u/L;肝铍含量分别为17.4μg和16.2μg。以上中毒组和治疗组间各指标比较均有显著性差异(P<0.05或P<0.01)。本实验结果表明喹胺酸对急性铍中毒大鼠的肝功能有明显的保护作用。     

618环氧树脂灌浆液肝脏毒性及脂质过氧化作用的实验研究

本文报道了618环氧树脂灌浆液(JX-1)对大鼠肝脏毒性和脂质过氧化作用与微粒体酶活性、巯基含量的关系。以 JX-1177.25毫克/公斤一次经口染毒后不同时间测定,血清转氨酶活性明显升高,12小时影响最明显,SGOT/SGPT 比值大于1。剂量在855.11毫克/公斤以上时,各组脂质过氧化值均升高,葡萄糖-6-磷酸酶活性与巯基含量降     

胍丁胺和尼莫地平对锰致大鼠兴奋性毒性影响

目的 研究胍丁胺和尼莫地平对锰引起的大鼠脑纹状体谷氨酰胺合成酶、磷酸激活的谷氨酰胺酶和脑皮质Na -K -ATP酶、Ca2 -ATP酶活性变化的影响.方法 32只大鼠按体重随机分成4组,第1组为对照组;第2组为单纯染锰组,第3,4组分别为胍丁胺和尼莫地平预处理干预组,连续干预并染锰4周.最后1次染毒后24h,将每组大鼠直接处死,断头取脑,在冰浴下分离脑纹状体和皮质,应用比色法测定脑纹状体中谷氨酰胺合成酶、磷酸激活的谷氨酰胺酶和脑皮质中Na -K -ATP酶和Ca2 -ATP酶的活性.结果 在单纯染200 umol/kg的氯化锰组中,谷氨酰胺合成酶[(50.41±5.47)U/(min·g·pro)]、Na -K -ATP酶(2.13±0.15)umol/(h·mg)、Ca2 -ATP酶(0.56±0.28)umol/(h·mg),3种酶与对照组比较活性明显降低(P<0.01),磷酸激活的谷氨酰胺酶(72.24±9.38)umol/(min·g·pro),与对照组比较活性明显升高(P<0.01);而21.9umol/kg的胍丁胺和2.4mmol/kg的尼莫地平预处理干预组与单纯染锰组比较,谷氨酰胺合成酶、Na -K -ATP酶、Ca2 一ATP酶活性明显升高(P<0.01).磷酸激活的谷氨酰胺酶活性明显降低(P<0.01).结论 胍丁胺和尼莫地平对锰致大鼠兴奋性毒性有一定的保护作用.     

四氯化碳致大鼠肝损伤时脱氢酶活性的变化

本文从脂质过氧化角度,探讨CCl_4致大鼠肝损伤时葡萄糖-6-磷酸脱氢酶(G-6-PD)和6-磷酸葡萄糖酸脱氢酶(6-PGAD)的活性变化。实验结果表明:G-6-PD 活性染毒后12小时降低,24小时回升,48小时继续升高;而6-PGAD 活性染毒后12小时上升,24小时继续升高,48小时恢复正常。经分析认为:肝中毒肘这二种酶活性的变化与CCl_4引起脂质过氧化的损伤机理是吻合的,这两种酶活性与氧化还原循环的受阻和调节密切相关。     

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.     

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.     

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.     

Fatigue and health in a seafaring population

Background Occupational fatigue is relatively common withinthe general population and has been linked to reduced performance,injury and longer term ill-health. Despite growing acknowledgementof this problem in the maritime sector, little research hasbeen conducted into the risk factors, prevalence and consequencesof seafarers' fatigue. Aims To examine the prevalence of fatigue among seafarers, identifypotential risk factors and assess possible links with poor performanceand ill-health. Methods Cross-sectional questionnaire survey of seafarers workingin the offshore oil support, short-sea and deep-sea shippingindustries. A number of tools were used including the fatiguesubscale of the profile of fatigue-related symptoms, the CognitiveFailures Questionnaire, the General Health Questionnaire andthe SF36 General Health scale. Results In all, 1855 questionnaires were completed giving anoverall response rate of 20%. Fatigue symptoms were associatedwith a range of occupational and environmental factors, manyunique to seafaring. Reporting a greater number of risk factorswas associated with greater fatigue [e.g. OR = 2.53 (1.90–3.35)for those with three or four risk factors and OR = 9.54 (6.95–13.09)for those with five or more risk factors]. There was also astrong link between fatigue and poorer cognitive and healthoutcomes, with fatigue the most important of a number of riskfactors, accounting for 10–14% of the variance. Conclusions Seafarers' fatigue could impact on safety withinthe industry and may be linked to longer term individual ill-health.It can only be addressed by considering how multiple factorscombine to contribute to fatigue.     

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.     

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.