环氧乙烷四氢呋喃共聚醚对雄性小鼠生殖毒作用的研究

实验研究了环氧乙烷四氧呋喃共聚醚（ＰＴＥ）对雄性小鼠的生殖毒作用。结果表明：６５ｍｇ／ｋｇ剂量组，ＬＤＨ总活力及ＬＤＨ－Ｘ、ＳＤＨ、γ－ＧＴ活性、ＭＤＡ含量、血清睾丸酮水平均未见明显改变。剂量增加至１３０ｍｇ／ｋｇ时，在停止染毒后２４小时，仅ＬＤＨ－Ｘ的活性增高（Ｐ＜０．０５），剂量为２６０ｍｇ／ｋｇ组停止染毒后２４小时，ＬＤＨ－Ｘ活性增高（Ｐ＜０．０５），但ＳＤＨ活性降低（Ｐ＜０．０５），２周２     

二硫化碳对大鼠肝脏脂质过氧化作用的研究

观察了二硫化碳（ＣＳ２）腹腔注射染毒对大鼠肝脏脂质过氧化物（ＬＰＯ）含量超氧化物歧化酶（ＳＯＤ）和谷胱甘肽过氧化物酶（ＧＳＨ－ＰＸ）活力的影响，急性染毒实验结果显示，大鼠肝ＬＰＯ含量随ＣＳ２染毒剂量增加而明显升高（ｒ＝０．８１０８，Ｐ＜０．０１），ＳＯＤ活性随剂量增加有降低趋势，ＧＳＨ－ＰＸ活性未见显著变化。亚急性实验结果显示，染毒２１ｄ染毒组ＧＳＨ－ＰＸ活力，染毒４５ｄ染毒组ＳＯＤ及ＧＳＨ－ＰＸ活力与对照组比较均显著降低（Ｐ＜０．０５），这表明，ＣＳ２是一个重要的致脂质过氧化物。     

谷胱甘肽及VitB6对CS2染毒大鼠的保护作用研究

目的：为探讨金属离子络合及ＶｉｔＢ６代谢障碍在二硫化碳（ＣＳ２）神经毒作用中的作用；方法：测定ＣＳ２染毒大鼠脑组织中微量元素铜的含量，并用ＶｉｔＢ６及谷胱甘肽（ＧＳＨ）进行干预。以ＳＤ雄性大鼠为中毒模型，检测不同浓度（０，３００，６００，１２００，２４００ｍｇ／ｍ３）染毒两个月后脑组织铜的含量；同时在高浓度（２４００ｍｇ／ｍ３）组给予两种干预药物：ＧＳＨ（１００ｍｇ／ｋｇ，腹腔注射，一次／日），ＶｉｔＢ６（灌胃，一次／日，０．４ｍｇ／日），观察对大鼠行为及酶活性的影响。结果：ＣＳ２染毒大鼠脑组织铜含量无明显改变；ＧＳＨ，ＶｉｔＢ６对ＣＳ２致运动协调能力障碍无明显改善，对反映学习记忆能力的指标（步下法）有改善作用；ＧＳＨ对Ｎａ＋－Ｋ＋－ＡＴＰ酶活性有升高作用。结论：ＣＳ２所致中枢神经系统与外周神经系统毒性在机制上可能有所不同。     

急性铬化物暴露肺损伤的剂量效应与时间过程

经一次气管灌注不同剂量可溶性六价铬酸钠（Ｎａ２ＣｒＯ４）后第２天和一次灌注０．９８ｍｇ·ｋｇ－１Ｎａ２ＣｒＯ４后不同时间，观察了ＳＤ大鼠支气管肺泡灌洗液（ＢＡＬＦ）和血液生化改变的剂量效应与时间过程。结果表明，Ｎａ２ＣｒＯ４的无效应剂量与阈剂量分别为０．００８和０．０４ｍｇ·ｋｇ－１，染毒剂量≥０．２０ｍｇ·ｋｇ－１时，ＢＡＬＦ中绝大多数生化参数呈现显著的剂量依赖性增加；严重中毒剂量（≥０．９８ｍｇ·ｋｇ－１）可引起ＢＡＬＦ和血液中几乎所有测试参数的显著增加，这种现象约持续一周，至少需要４周才能恢复正常。分析本次研究结果，可得出以下结论：≥０．９８ｍｇ·ｋｇ－１的Ｎａ２ＣｒＯ４可导致包括肺内细胞损伤、弥漫性肺泡炎和肺水肿在内的急性肺损伤；Ｎ－乙酰－β－Ｄ－氨基葡糖苷酶（ＮＡＧ）、溶菌酶（ＬＹＳ）、碱性磷酸酶（ＡＬＰ）、白蛋白（ＡＬｂ）和血管紧张素转换酶（ＡＣＥ），可能是评价接触较低剂量Ｎａ２ＣｒＯ４（＜０．９８ｍｇ·ｋｇ－１）后所致急性肺损伤的最有价值的早期敏感指标     

甲基汞对卵巢细胞酶及其线粒体的影响

用氯甲基汞（以１／２００ＬＤ５０、１／２０ＬＤ５０和１／２ＬＤ５０即０．１９２５ｍｇ／ｋｇ、１．９２５ｍｇ／ｋｇ和１９．２５ｍｇ／ｋｇ体重的剂量）给昆明种雌性小鼠经口染毒，然后测定卵巢细胞中的ＬＤＨ、Ｇ－６－ＰＤ和ＳＤＨ活性，同时做卵巢细胞线粒体的电镜观察。结果表明：各剂量组的ＬＤＨ、Ｇ－６－ＰＤ活性明显低于对照组（Ｐ＜０．０５）。１／２ＬＤ５０和１／２０ＬＤ５０组的ＳＤＨ活性也明显低于对照组（Ｐ＜０．０５）。从电镜看到线粒体膜较完整，但在１／２ＬＤ５０和１／２０ＬＤ５０组中的线粒体嵴数目减少，甚至完全消失，基质呈空泡状改变。总之，酶活性改变，能量代谢的异常和线粒体的损伤可能是氯化甲基汞造成卵巢细胞功能改变的重要原因。     

铜离子对草履虫毒性实验研究

通过铜离子（Ｃｕ~２＋）对革履虫的毒性及其对脂质过氧化物（ＬＰＯ）、谷胱甘肽（ＧＳＨ）和乳酸脱氢酶（ＬＤＨ）含量影响的实验研究结果表明：Ｃｕ~２＋浓度在０．０３９～３９．８ｍｇ／Ｌ范围内革履虫的死亡率随Ｃｕ~２＋浓度的增加而升高（ＬＣ５０＝３．９１ｍｇ／Ｌ，ｔ＝１ｈ），ＧＳＨ和ＬＤＨ含量随Ｃｕ~２＋浓度的增加而下降，而ＬＰＯ则升高，ＧＳＨ和ＬＰＯ与死亡率呈极显著的负相关（ｒ＝－０．８４８Ｐ＜０．０１），ＬＤＨ和ＬＰＯ则没有任何联系（Ｐ＞０．０５）。然而在Ｃｕ~２＋浓度小于０．０３９１ｍｇ／Ｌ时革履虫的ＧＳＨ和ＬＤＨ均升高，而ＬＰＯ则处于最低点，刺丝泡发射能力正常。提示：Ｃｕ~２＋急性中毒作用可能抑制草履虫的ＧＳＨ，导致细胞膜结构的稳定性及抗氧化能力降低，使细胞体脂质过氧化作用加强，细胞膜结构受损而引起死亡；观察刺丝泡是一项对革履虫毒性损伤的重要指标；微量的Ｃｕ~２＋对革履虫的代谢等有刺激作用。     

锌,硒,维生素E,维生素C对二硫化碳致脂质过氧化作用影响？…

目的 观察锌（Ｚｎ）、硒（Ｓｅ）、维生素Ｅ（ＶｉｔＥ）、维生素Ｃ（ＶｉｔＣ）对二硫化碳（ＣＳ２）致脂质过氧化作用的影响。方法 采用三因素四水平拉丁方设计,观察４个剂量水平的４种抗氧化剂（Ｚｎ、Ｓｅ、ＶｉｔＥ、ＶｉｔＣ）对４个剂量水平（３６０、２４０、１２０和０ｍｇ／ｋｇ）ＣＳ２亚慢性染毒ＳＤ大鼠血清、心肌和肝脏脂质过氧化水平（ＬＰＯ）的影响。结果 抗氧化剂高剂量组大鼠血清、心肌与高、中剂量组大鼠肝     

镉对大鼠睾丸间质细胞脂质过氧化的影响

目的观察镉对离体睾丸间质细胞的毒性作用。方法测定不同ＣｄＣｌ２染毒浓度下（含镉０、１０、２０和４０μｍｏｌ／Ｌ）间质细胞的脂质过氧化水平。结果染毒２４小时后，染毒组的细胞存活率显著低于对照组（Ｐ＜０．０１），且存在剂量－效应关系；随染毒浓度的增高，丙二醛（ＭＤＡ）含量和谷胱甘肽过氧化物酶（ＧＳＨ－Ｐｘ）活力显著增高（Ｐ＜０．０５），而超氧化物歧化酶（ＳＯＤ）活力则显著下降（Ｐ＜０．０１）。相关分析结果显示：ＳＯＤ与ＭＤＡ呈负相关、与ＧＳＨ－Ｐｘ呈显著负相关（ｒ＝－０．４３３９，Ｐ＜０．０５）；ＭＤＡ与ＧＳＨ－Ｐｘ呈显著正相关（ｒ＝０．４３２９，Ｐ＜０．０５），表明镉可使睾丸间质细胞的脂质过氧化作用增强、抗氧化能力减弱。结论镉对睾丸间质细胞具有直接毒性作用。     

硝基苯对小鼠睾丸细胞酶的作用

以剂量为１００ｍｇ／ｋｇ体重、５００ｍｇ／ｋｇ体重的硝基苯（ＮＢ）分别给雄性小白鼠经口染毒。染毒２天后，各染毒组的睾丸组织中Ｇ－６－ＰＤ、ＬＤＨ－ｘ、ＳＤＨ的活性均明显低于对照组。染毒４天后，染毒组Ｇ－６－ＰＤ活性恢复到对照水平；ＬＤＨ－ｘ的１００ｍｇ／ｋｇ体重组恢复到对照水平，而５００ｍｇ／ｋｇ组仍明显低于对照组；ＳＤＨ活性染毒组仍低于对照组。ＬＰＯ值在染毒２天、４天后与对照组相比均无显著差异。     

氯化甲基汞对卵巢细胞酶及其线粒体的影响

用氯化甲基汞（以１／２００ＬＤ５０、１／２０ＬＤ５０和１／２ＬＤ５０即０．１９２５ｍｇ／ｋｇ、１．９２５ｍｇ／ｋｇ和１９．２５ｍｇ／ｋｇ体重的剂量）给昆明种雌性小鼠经口染毒，然后测定卵巢细胞中的ＬＤＨ、Ｇ－６－ＰＤ和ＳＤＨ活性，同时做卵巢细胞线粒体的电镜观察。结果表明：各剂量组的ＬＤＨ、Ｇ－６－ＰＤ活性明显低于对照组（Ｐ＜０．０５）。１／２ＬＤ５０和１／２０ＬＤ５０组的ＳＨＤ活性也明显低于对照组（Ｐ＜０．０５）。从电镜看到线粒体膜较完整，但在１／２ＬＤ５０和１／２０ＬＤ５０组中的线粒体嵴数目减少，甚至完全消失，基质呈空泡状改变。总之，酶活性改变，能量代谢的异常和线粒体的损伤可能是氯化甲基汞造成卵巢细胞功能改变的重要原因。     

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.     

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.     

The design of hazard risk assessment matrices for ranking occupational health risks and their application in mining and minerals processing

Two hazard risk assessment matrices for the ranking of occupational health risks are described. The qualitative matrix uses qualitative measures of probability and consequence to determine risk assessment codes for hazard-disease combinations. A walk-through survey of an underground metalliferous mine and concentrator is used to demonstrate how the qualitative matrix can be applied to determine priorities for the control of occupational health hazards. The semi-quantitative matrix uses attributable risk as a quantitative measure of probability and uses qualitative measures of consequence. A practical application of this matrix is the determination of occupational health priorities using existing epidemiological studies. Calculated attributable risks from epidemiological studies of hazard-disease combinations in mining and minerals processing are used as examples. These historic response data do not reflect the risks associated with current exposures. A method using current exposure data, known exposure-response relationships and the semi-quantitative matrix is proposed for more accurate and current risk rankings.