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。     

醋酸铅对雄性小鼠生殖功能的影响

给雄性小鼠灌胃染毒醋酸铅 10mg/kg、 2 0mg/kg和 40mg/kg ,每天 1次连续 3 5d。应用分光光度法测定血清和睾丸中酶活性 ,按标准方法测定小鼠生育力 ,并对睾丸、附睾进行组织病理学检查。结果表明 ,雄鼠受精率、雌鼠妊娠率、平均每窝活胎率及睾丸匀浆中的 β G和LDHx随染毒剂量增加而降低 ,死胎率和吸收胎率随染毒剂量增加而升高 ,与阴性对照组比较差异均有显著性 (P <0 0 5 ) ,并呈现明确的剂量 反应关系 ,r值依次为 -0 412、 -0 42 0、-0 5 3 7、 -0 5 3 8、 -0 617、 0 5 42和 0 5 3 5。雄鼠交配率 ,血清和睾丸匀浆中G 6 PD、ACP、LDH仅在 40mg/kg组与阴性对照组比较差异有高度显著性和显著性 (P <0 0 1或P <0 0 5 )。说明染毒醋酸铅≥ 2 0mg/kg剂量可损害雄性小鼠生殖功能。     

二氯苯胺对小鼠睾丸中某些酶的影响

以150、300、600 mg/kg剂量小鼠灌胃染毒2,3-二氯苯胺,测定小鼠睾丸匀浆上清液中还原性谷胱甘肽(GSH)的含量、超氧化物歧化酶(SOD)以及乳酸脱氢酶x(LDHx)的活性。与对照组比较,低剂量的2,3-二氯苯胺对小鼠睾丸GSH含量以及SOD酶活性有一定的抑制作用,随着2,3-二氯苯胺染毒剂量增加,GSH含量和SOD酶活性显著升高,LDHx酶活性显著降低。提示2,3-二氯苯胺对小鼠睾丸组织中的某些酶活性有一定的影响。     

呋喃丹对大鼠睾丸组织标志酶活性影响的动态观察

为探讨农药呋喃丹对雄性大鼠睾丸组织的损害作用 ,以低、中、高剂量 (0 3、1 5和 3 0mg kgBW)经口连续染毒 77天 ,分别于染毒第 7、35和 77天检测大鼠血清及睾丸组织匀浆中 β-葡萄糖苷酶 (β-G)、葡萄糖 - 6 -磷酸脱氢酶 (G - 6 -PD)、乳酸脱氢酶同工酶X(LDHx、)的活性。结果显示 ,染毒第 7天大鼠 3个染毒组血清中 β -G活性显著低于对照组 (P <0 0 5) ,低剂量组睾丸组织匀浆中 β -G活性高于对照组、而高剂量组低于对照组 (P <0 0 5) ;染毒第 77天中高剂量组血清中G - 6 -PD活性 ,高剂量组睾丸组织匀浆中LDHx活性均低于对照组 (P <0 0 5) ,其它指标及时段未见明显改变。提示呋喃丹对大鼠睾丸组织有一定损害作用。     

丙烯腈对大鼠睾丸抗氧化酶活力和脂质过氧化水平的影响

目的　探讨丙烯腈(ACN)的雄性生殖毒性机制。方法　健康雄性SD大鼠分别以0、7.5、15.0、30.0 mg/kg剂量腹腔注射ACN染毒,测定其睾丸谷胱甘肽(GSH)、丙二醛(MDA)含量和超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH Px)、谷胱甘肽S 转移酶(GST)活力。结果　ACN染毒4周后,15.0、30.0 mg/kg组大鼠睾丸GSH含量[(7.44±0.96)、(6.95±0.77)mg/g pro]增加,30.0 mg/k组大鼠GSH Px活力[(70.89±4.01)U/mg pro]升高,与对照组的差异均有统计学意义(P<0.05,P<0.01)。ACN染毒8周后,30.0 mg/kg组大鼠睾丸GSH含量[(2.50±0.94)mg/g pro]降低,15.0、30.0mg/kg组大鼠SOD活力[(102.08±16.08)、(113.30±17.20)NU/mg pro]升高,与对照组的差异均有统计学意义(P<0.01)。ACN染毒13周后,15.0、30.0 mg/kg组大鼠睾丸GSH含量降低,30.0 mg/kg组GST活力下降,各染毒组GSH Px活力均低于对照组,30.0 mg/kg组MDA含量[(0.68±0.16)nmol/mgpro]高于对照组[(0.38±0.12)nmol/mg pro],差异均有统计学意义(P<0.01)。停止染毒后2周,大鼠睾丸GSH水平恢复;30.0 mg/kg组大鼠睾丸MDA含量下降,但仍高于对照组,GSH Px活力仍低于对照组,差异均有统计学意义(P<0.05)。结论　ACN能通过破坏氧化-抗氧化体系的平衡,诱导雄性大鼠睾丸脂质过氧化损伤。     

壬基酚对大鼠睾丸和血清中某些生化指标的影响

目的研究环境类激素壬基酚对大鼠睾丸和血清中某些生化指标的影响.方法以壬基酚50、100、200 mg/kg剂量对Wistar雄性大鼠连续经口染毒35 d,检测大鼠睾丸组织匀浆及血清中β-葡萄糖醛酸苷酶(β- G )、乳酸脱氢酶同工酶(LDHx)、超氧化物歧化酶(SOD)的活性及谷胱甘肽(GSH)、丙二醛(MDA) 含量,血中睾酮(T)、雌二醇(E2)水平.结果 50 mg/kg处理组睾丸组织中β-G和200 mg/kg处理组血清中LDHx活性显著高于对照组(P＜0.05);200 mg/kg处理组睾丸组织中SOD活性及血中T含量显著低于对照组(P＜0.05).结论壬基酚可能会诱发大鼠睾丸和血清某些生化指标的改变,表明对睾丸有损伤.     

乙二醛对小鼠抗氧化物酶活力的影响

目的　通过观察乙二醛 (glyoxal)染毒小鼠全血及组织中谷胱甘肽过氧化物酶 (GSH Px)及超氧化物歧化酶 (SOD)活力的变化 ,探讨乙二醛对抗氧化酶活力的影响。方法　采用腹腔注射法 ,小鼠染毒2 4h后经摘眼球法采集血样 ,将小鼠颈椎脱臼处死后取心、肝、肾和脑组织 ,并制成匀浆 ,分别以二硫双硝基苯甲酸 (DTNB)法及亚硝酸盐法测定全血及组织中GSH Px及SOD的活力。结果　全血和肾脏的低、中、高剂量组及肝脏高剂量组GSH Px活力显著低于对照组 (P <0 0 5或P <0 0 1) ,心、脑、肾的高剂量组及肝脏的低、中剂量组SOD活力与对照组相比 ,差异具有显著性 (P <0 0 5或P <0 0 1)。结论　乙二醛对全血中GSH Px活力的影响主要表现为抑制作用 ,对肝脏中GSH Px活力的影响主要为应激性增高 ,乙二醛对组织中SOD活力的影响主要表现为应激性增高趋势     

铅对小鼠睾丸组织脂质过氧化作用及杭白菊对其保护作用的研究

本文通过给雄性小鼠腹腔注射醋酸铅染毒,测定各不同染毒剂量组与空白对照及杭白菊灌胃组中血铅、血浆中VitC和小鼠睾丸组织中T—SOD、GSH—Px活力,MDA含量．以观察铅对小鼠睾丸组织脂质过氧化作用及杭白菊对其保护作用。结果表明：铅染毒组T—SOD活力和GSH—Px活力下降．其中T—SOD活力与铅含量呈负相关（r＝-0．6098,P＜0．01）;杭白菊灌胃组T—SOD和GSH—Px活力上升,与铅染毒组相比,差异显著（P＜0．05）,其中GSH—Px恢复到对照水平。杭白菊灌胃组较染毒组血铅含量下降,血浆中VitC含量上升,差异显著（P＜0．05）。     

不同价态锰对神经母细胞瘤细胞的氧化损伤作用

目的　探讨不同价态、不同浓度锰引起神经细胞的脂质过氧化对细胞的损伤作用。方法　分别用 0 ,0 2 5 ,0 5 0 ,0 75mmol/L二价锰、三价锰对神经母细胞瘤细胞 (SH SY5Y)染毒 2 4h ,观察测定细胞超氧化物歧化酶 (SOD)、谷胱甘肽过氧化物酶 (GSH Px)、丙二醛 (MDA)、GSH Px/MDA及细胞膜脂荧光各向异性的变化。结果　二价锰、三价锰染毒各低、中、高剂量组细胞SOD活力 [(5 2 2 1 2± 5 7 74 ) ,(4 98 38± 37 2 9) ,(4 6 4 86± 2 4 0 9)和 (4 99 79± 30 86 ) ,(4 77 2 3± 6 1 6 6 ) ,(4 35 95± 74 0 4 )NU/mg蛋白 ]与对照组[(86 1 2 4± 35 74 )NU/mg蛋白 ]比较明显降低 ,差异有显著性 (P <0 0 5 ) ;GSH Px活力 [(1 9 0 4± 5 1 6 ) ,(1 7 74± 5 91 ) ,(1 5 99± 5 6 2 )和 (1 6 5 8± 6 1 9) ,(1 5 79± 7 2 9) ,(1 4 2 3± 5 2 0 )活力单位 ]均较对照组[(2 9 2 3± 7 83)活力单位 ]降低 ,差异有非常显著性 (P <0 0 1 ) ;GSH Px/MDA较对照组降低 ,差异有显著性 (P <0 0 5 ) ,而MDA和细胞膜脂荧光各向异性有所升高 (P <0 0 5 ) ;相同染毒剂量情况下 ,三价锰组上述指标的变化比二价锰组明显。结论　锰通过抑制SOD、GSH Px活力 ,降低细胞抗氧化能力 ,造成细胞膜功能的损伤。三     

桐油对小鼠机体抗氧化能力的影响

[目的 ]实验观察桐油对小鼠机体抗氧化能力的影响。 [方法 ]将 40只BALB/C小鼠分为 4组 ,分别经口染毒桐油 0 ,2 0 0 0 ,40 0 0 ,6 0 0 0mg/kg,1次 /d ,连续 5d。 7d后测定血清超氧化歧化酶 (SOD)、总抗氧化能力及全血谷胱甘肽氧化酶 (GSH Px)的活性。 [结果 ]桐油染毒 4 0 0 0 ,6 0 0 0mg/kg的 2组小鼠 ,SOD、GSH Px活性和总抗氧化能力均低于对照组 (P <0 0 1 )。 [结论 ]口服 4 0 0 0mg/kg以上桐油有抑制小鼠机体抗氧化能力的作用     

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 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.     

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.     

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.     

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.