镍染毒对小鼠脾脏的脂质过氧化损伤

目的从氧化应激角度探讨硫酸镍致小鼠脾脏脂质过氧化水平和抗氧化能力的变化。方法硫酸镍0．8，2．0，5．0mg／kg小鼠每日愎腔注射染毒，连续30d。制备脾脏组织匀浆，采用分光光度法测定脾脏总抗氧化能力(T—AOC)和谷胱甘肽(GSH)含量；黄嘌呤氧化酶法测定超氧化物歧化酶(SOD)活力；用TBA法测定丙二醛(MDA)含量。结果镍可抑制小鼠脾脏SOD活力，使T—AOC和GSH含量降低，MDA含量增加，并随染毒剂量增加，其效应逐渐增加。结论硫酸镍可致小鼠脾脏抗氧化能力下降，引起脂质过氧化损伤。     

泛酸钙对全饥饿大鼠脑组织脂质过氧化的影响

目的：探讨泛酸钙对全饥饿大鼠脑脂质过氧化产物（MDA），还原型谷胱甘肽（GSH），谷胱甘肽过氧化物酶（GSH－Px)，超氧化歧化酶（SOD）的影响及可能的脑保护机制，方法：以饥饿SD大鼠为模型，灌胃补充泛酸钙，观察大鼠饥饿后不同时期脑MDA，GSH，GSH－Px及SOD的变化。结果：饥饿后大鼠脑MDA含量明显升高，泛酸钙补充后大鼠脑MDA量在禁食4与7天较饥饿前无明显升,高，与全饥饿对照组比较差异显，泛酸钙对饥饿大鼠脑SOD，GSH－Px活力无影响，但显提高GSH水平。结论：泛酸钙能抑制饥饿大鼠脑的脂质过氧化损伤，其部分作用可能是通过提高GSH水平来实现的。     

有氧运动对衰老的大鼠脑组织抗氧化蛋白的影响

目的研究有氧运动对衰老的大鼠脑组织抗氧化能力的影响。方法建立衰老大鼠模型,随机分为对照组和3组运动组（A组、B组、C组）,A组给予0．5h的游泳训练,B组给予1h的游泳训练,C组给予2h的游泳训练,12周后取大脑组织,检测超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH—Px）、总抗氧化能力（T—AOC）以及丙二醛（MDA）的含量。结果建模6周后,造模组的SOD、GSH—Px、T—AOC水平分别为（38．52±7．63）U／ml、（2．14±0．52）U／ml、（3．13±0．94）10^3U／g,都低于空白对照组,与老龄化组相当,MDA高于空白对照组;经过12周的有氧运动,A、B和C组的SOD、GSH—Px、T-AOC水平均高于衰老对照组,MDA低于衰老对照组。结论有规律的有氧运动能提高衰老大脑的抗氧化能力,提高大脑组织中SOD和GSH—px活力,有效降低MDA的含量,延缓衰老。     

PM2.5对大鼠肝、脾、肾组织的氧化损伤效应

目的探讨PMU对大鼠肝、脾、肾组织抗氧化酶活力和脂质过氧化（LPO）水平的影响。方法选取32只雄性Wistar大鼠,随机分为4组,分别用0、1．5、7．5、37．5mg／kg的PMu经气管注入染毒后24h处死大鼠,测定肝、脾、肾组织超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GSH—Px）活力,谷胱甘肽（GSH）和硫代巴比妥酸反应物（TBARS）含量。结果PM”染毒组大鼠肝、肾组织内SOD、CAT、GSH—Px活力和SOD／TBARS比值均较对照组降低（P〈0．05,P〈0．01）,具有剂量一效应关系。各染毒组TBARS／GSH—Px比值较对照组显著升高（P〈0．01,P〈0．001）。染毒组脾、肾组织GSH含量较对照组显著下降（P〈0．05,P〈0．01）,而染毒组肝组织GSH含量则出现先升高后降低的非线性变化特征（P〈0．01,P〈0．05）。染毒组肝组织LPO水平出现剂量-效应性升高（P〈0．05）,染毒组脾组织各种抗氧化酶活力、LPO水平和TBARS／GSH—Px比值均未见显著变化。结论PM2.5可引起大鼠肝、肾组织的氧化损伤。     

亚慢性铝暴露对大鼠神经行为学指标和脑组织脂质过氧化的影响

目的研究亚慢性铝染毒对断乳大鼠神经行为学指标和脑脂质过氧化的影响．以探讨铝对发育中大鼠中枢神经系统的毒性作用及其机制。方法将初断乳清洁级Wistar大鼠随机分为对照组（蒸馏水）、低剂量组（2g／L AlCl3溶液）、高剂量组（4g／L AlCl3溶液），每组10只，自由饮水摄入AlCl3，连续染毒12周。染毒后，称量各组大鼠体重和脑组织重量，计算脑组织系数，采用原子吸收石墨炉法测定血铝含量，采用跳台试验法观察大鼠学习、记忆行为学的改变，采用氧化损伤试剂盒测定脂质过氧化水平[丙二醛（MDA）含量、还原型谷胱甘肽（GSH）含量和超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH—Px）活力]。结果高剂量组大鼠脑组织系数低于对照组，差异有统计学意义（P〈0．05）。随着染铝剂量的增加，血铝水平呈上升趋势（P〈0．01）。跳台试验结果显示，随铝暴露剂量的增加，大鼠的潜伏期逐渐缩短，而错误次数逐渐增加，有明显的剂量-效应关系（P〈0．01）。随着染铝剂量的增加，脑组织中MDA含量显著升高（P〈0．01），SOD活力下降；GSH含量和GSH—Px活力先上升后降低。不同组别雌雄大鼠间各指标比较，差异均无统计学意义（P〉0．05）。结论亚慢性铝暴露可以引起发育中大鼠学习记忆能力下降，脑脂质过氧化水平提高。     

刺梨汁对高氟摄入大鼠肝肾脂质过氧化作用的影响

利用自由进食含氟320mg／kg饲料和饮用刺梨汁水喂养大鼠6个月的动物模型，探讨刺梨汁对高氟摄入大鼠肝肾脂质过氧化损害的影响。结果发现：刺梨汁能拮抗高氟引起的肝肾组织抗氧化能力降低，使肝肾还原型谷胱甘肽（GSH）含量和谷胱甘肽过氧化物酶（GSH—Px）、超氧化物歧化酶（SOD）活性降低显著回升；拮抗肝肾组织脂质过氧化增强，使肝肾脂质过氧化物（LPO）含量升高程度显著回降；从而拮抗肝肾损害，使肝甘油三脂（TG）含量和尿γ－谷氨酰转移酶（γ—GT）活性升高显著回降。表明刺梨汁对高氟摄入大鼠肝肾脂质过氧化损害具有明显的拮抗作用。     

电刺激对大鼠大脑、肝等组织脂质过氧化水平的影响

[目的 ]探讨电刺激应激对实验动物体内脂质过氧化水平以及抗氧化能力的影响。 [方法 ]采用 5 0Hz的强脉冲、电压为 10 0V交流电对实验大鼠连续 10d进行电刺激 ,观察受刺激后大鼠肝、大脑组织中抗氧化酶GSH Px、GST和抗氧化物质GSH以及反映脂质过氧化水平的脂质过氧化代谢产物MDA的含量。 [结果 ]受试大鼠肝和大脑组织中抗氧化物质GSH含量明显下降和MDA含量明显升高 ,抗氧化酶GSH Px、GST的活性明显下降 ,与对照组相比P <0 0 5和P <0 0 1。 [结论 ]电刺激应激能增强大鼠脑和肝组织脂质过氧化水平     

呋喃丹对雄性大鼠急性生殖损伤的研究

目的：探讨农药呋喃丹对雄性大鼠生殖系统急性损害作用。方法：以0．3，1．5，3．0mg/kg剂量经口染毒7d，检测大鼠血清及睾丸组织匀浆中脂质过氧化指标超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px)、丙二醛（MDA）、活性氧，睾丸组织标志酶β－葡萄糖醛酸苷酶（β-G）、葡萄糖－6磷酸脱氢酶（G－6－PD）、乳酸脱氢酶同工酶X（LDHx）及一氧化氮（NO）、一氧化氮合酶（NOS）的含量或活力。结果：染毒7d大鼠血清GSH－Px、β-G、NOS活力下降，睾丸组织匀浆中MDA、活氧含量及β－G、NOS活力升高（P＜0．05），GSH－Px、SOD活力下降（P＜0．05）。结论：短时间接触呋喃丹可对大鼠睾丸组织产生脂质过氧化作用，对睾丸组织有损害。     

番茄红素对急性肝损伤大鼠抗氧化酶的影响

目的　观察四氯化碳急性中毒对大鼠机体抗氧化酶活力的影响及番茄红素 (lycopene ,LP)的保护作用。方法　大鼠灌胃番茄红素 ,4周后以四氯化碳腹腔注射 ,2 4h后处死 ,测定血清和肝匀浆的超氧化物岐化酶 (SOD)活性 ,谷胱甘肽过氧化物酶 (GSH Px)活力 ,丙二醛 (MDA)含量 ,还原型谷胱肝肽 (GSH)含量及总抗氧化能力 (T AOC)。结果　与模型组相比 ,各番茄红素组的大鼠血清和肝组织的SOD活性 ,GSH Px活力上升 ,MDA含量降低 ,GSH含量升高 ,T AOC升高 ,差异有统计学意义 (P <0 0 5 )。结论　番茄红素可以提高大鼠机体的抗氧化能力 ,减轻四氯化碳对机体造成的肝损伤。     

慢性氟中毒对大鼠脑组织脂质过氧化水平和抗氧化能力的影响

目的研究氟在大鼠脑组织中的蓄积及其对脂质过氧化水平和抗氧化能力的影响。方法用氟化钠对大鼠进行亚慢性染毒,测定大鼠脑组织中氟浓度和脂质过氧化产物丙二醛（MDA）的含量及抗氧化酶超氧化物歧化酶（SOD）、谷胱甘肽过氧化物氧化酶（GSH-Px）的活力。结果大鼠脑组织中氟浓度与染毒剂量呈正相关,高剂量组脑组织氟浓度明显高于低剂量组和对照组（P〈0．01）。脂质过氧化产物MDA含量在三组问差异有统计学意义（P〈0．01）,高剂量组MDA含量高于低剂量组,低剂量组高于对照组。抗氧化酶SOD和GSH-Px的活力三组间差异有统计学意义（P〈0．01）。但在组间比较时发现,低剂量组与对照组间差异没有统计学意义（P〉0．05）。高剂量组与低剂量组、对照组间差异有统计学意义（P〈0．01）。脑组织中氟浓度与MDA含量之间呈明显正相关（r=0．731,P〈0．01）,而与SOD和GSH．Px的相关性不明显（r分别为0．234和0．148,P〉0．05）,MDA与SOD和GSH-Px呈明显负相关（r分别为一0．571和0．591,P〈0．01）。结论氟可透过血脑屏障在大鼠脑内蓄积。过量的氟接触将导致机体抗氧化系统紊乱,脂质过氧化程度加剧,造成脑组织氧化性损伤。     

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.     

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.     

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.     

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.