混合染毒双酚A、壬基酚对小鼠生育力的影响

目的研究经口混合染毒双酚A(BPA)和壬基酚(NP)对小鼠的生殖和发育毒性。方法选择性成熟、清洁级、体重在22～26g的昆明种小鼠128只,随机区组分为(1)BPA24mg/kg+NP12mg/kg,(2)BPA60mg/kg+NP30mg/kg,(3)BPA120mg/kg+NP60mg/kg染毒组和阴性对照组,每组每性别16只小鼠,按10ml/kg灌胃染毒,1次/d,雄鼠连续染毒6周,雌鼠从交配前15d染毒至妊娠第6天结束。按EPA推荐的小鼠生育力测试方法进行实验研究。结果从BPA24mg/kg+NP12mg/kg组始生育指数、妊娠率、活胎率随染毒剂量增加而下降(P<0.05或P<0.01),而着床前死亡率、吸收胎率、死胎率随剂量增加而升高(P<0.05或P<0.01);从BPA60mg/kg+NP30mg/kg组始精子计数、活精率随染毒剂量增加而下降(P<0.05或P<0.01),精子畸形率随剂量增加而升高(P<0.05或P<0.01),而交配指数、平均胎长、平均胎重仅在BPA120mg/kg+NP60mg/kg组显著低于对照组(P<0.05或P<0.01)。结论经口较长时间混合染毒BPA和NP会对小鼠产生明显的生殖毒作用和胚胎发育毒性。     

壬基酚对小鼠生育力的影响研究

目的 研究壬基酚（NP）经口染毒对昆明种小鼠生育力的影响,并评价其生殖和发育毒性.方法 选择健康性成熟的清洁级的昆明种小鼠128只,体重22～26 g,随机分为24、60、120 mg/kg NP染毒组和1个花生油溶剂对照组,每组32只,雌雄各半.进行小鼠生育力试验.结果 从60 mg/kg组开始,精子计数、活精率、生育指数、妊娠率均随染毒剂量增加而下降,精子畸形率随剂量增加而升高（P＜0.05或P＜0.01）;交配指数仅在120mg/kg组下降（P＜0.05）;从24mg/kg组开始,平均每窝黄体数、着床数、活胎数均随染毒剂量升高而下降,存在明显的剂量-效应关系（P＜0.05或P＜0.01）;而着床前死亡率、吸收胎率、死胎率均随染毒剂量增加而升高（P＜0.05或P＜0.01）.结论 经口染毒壬基酚对小鼠产生明显的生殖和发育毒性.     

双酚A与壬基酚混合染毒对小鼠生精功能的影响

目的　研究双酚A (BPA)与壬基酚 (NP)混合染毒对小鼠生精功能的影响。方法　选择健康性成熟的雄性昆明种小鼠 6 0只 ,按随机区组分为阴性对照组、阳性对照组 (环磷酰胺 ,CP)和低剂量组(82mg/kgBPA+5 0mg/kgNP)、中剂量组 (1 6 3mg/kgBPA +1 0 0mg/kgNP)和高剂量组 (32 5mg/kgBPA+2 0 0mg/kgNP) ,连续灌胃染毒 5d ,分别于首次染毒后第 1 4天和第 35天 ,每组随机处死 5只小鼠 ,检测睾丸、附睾、精囊腺重量和脏器系数、精子数、精子活动度、活精率、精子畸形率和初级精母细胞染色体畸变率。结果　精子数、直线运动精子数和活精率随染毒剂量增加而减少 ,静止不动精子数、精子畸形率和初级精母细胞染色体畸变率均随染毒剂量增加而升高。中、高剂量组的上述结果与阴性对照组比较 ,差异均有显著性 (P <0 0 5 ,P <0 0 1 ) ,均存在明确的剂量 -反应关系 ,相关系数依次为 :- 0 987,- 0 895 ,- 0 981 ,0 981 ,0 95 8和 0 96 2 (均P <0 0 5 )。结论　BPA、NP及其代谢产物能损伤小鼠的生精功能 ,由于BPA、NP在环境中往往共存 ,所以在评价BPA、NP生殖功能的损伤作用时 ,必须考虑两化学物间的相互作用。     

壬基酚和辛基酚对小鼠遗传毒性联合作用

目的:研究壬基酚与辛基酚对小鼠遗传毒性的联合作用。方法:采用彗星试验和小鼠精子畸形试验,检测不同剂量(50、100、200 mg/kg)壬基酚、辛基酚单独染毒和联合染毒后小鼠睾丸细胞DNA损伤情况及精子畸形率。结果:联合染毒剂量为100、200 mg/kg时,小鼠睾丸细胞彗星率随联合染毒剂量增加而增加(P<0.01),彗星尾长随联合染毒剂量增加而延长(P<0.01),精子畸形率分别为13.8‰和7.6‰(P<0.05)。结论:壬基酚与辛基酚对小鼠睾丸细胞DNA有损伤作用,联合染毒具有遗传毒性。     

杭州湾南岸滩涂沉积物中POPs混合物对小鼠的生殖毒性作用

目的研究杭州湾南岸滩涂沉积物中POPs混合物对小鼠的生殖毒性作用. 方法选择健康清洁级性成熟ICR小鼠80只,体重22-26g,随机分为30,100,300mg/kg三个剂量染毒组和一个溶剂对照组,每组20只,雌雄各半,进行一代生殖毒性试验.采用灌胃方式进行染毒(10 ml/kg),雄鼠染毒6周,进行精子畸形测定.雌鼠染毒2周后,雌雄小鼠按1:1同笼交配,交配时间为2周,观察交配率及受孕率.孕鼠在妊娠19天解剖,观察黄体数,着床数,活胎数,死胎数,吸收胎数,每窝胎仔平均胎长,胎重,胎盘重.结果 当混合物染毒剂量为100 mg/kg和300mg/kg 时,精子畸形率明显升高(P<0.05),剂量达到300mg/kg时生育率,妊娠率,活胎率,平均胎长和胎仔重降低(P<0.05),而着床前死亡率,死胎率升高(P<0.05).结论 滩涂沉积物中POPs混合物在剂量达到300mg/kg时对小鼠产生明显的生殖和发育毒性.     

邻苯二甲酸(2-乙基己基)酯低剂量暴露对雄性小鼠生殖发育的影响

目的观察邻苯二甲酸(2-乙基己基)酯(DEHP)低剂量暴露对雄性小鼠的生殖发育毒性作用。方法将清洁级ICR小鼠随机分为4个DEHP染毒组(1/120LD50,1/60LD50,1/30LD50,1/15LD50,即250、500、1000、2000mg/kg组),阳性对照组(环磷酰胺,40mg/kg)和阴性对照组(玉米油);DEHP染毒组和阴性对照组灌胃染毒30d,阳性对照组灌胃5d,每天1次。采用一般生殖毒性试验和显性致死突变试验的方法,研究DEHP低剂量暴露对雄性小鼠生殖细胞的损伤作用和生育能力的影响。结果一般生殖毒性试验结果显示,低剂量DEHP染毒雄性小鼠睾丸、附睾重量降低(r睾丸=-0.578,P<0.01;r附睾=-0.661,P<0.01),精子总数减少(r=-0.608,P<0.01),精子畸形率增高(r=0.836,P<0.01),精子活动度降低(P<0.05)。显性致死突变试验研究结果显示,250mg/kgDEHP染毒组小鼠受孕率降低,但与阴性对照组比较,差异无统计学意义(P>0.05);DEHP染毒组子代小鼠平均着床数减少(r=-0.892,P<0.01),与阴性对照组比较,差异均具有统计学意义(P<0.01);平均早期死亡胚胎数随染毒剂量增加而增加(r=0.996,P<0.01),250mg/kg染毒组与阴性对照组比较,差异无统计学意义(P>0.05)。结论DEHP低剂量暴露对雄性小鼠具有生殖毒性作用,可降低小鼠受孕率,使子代小鼠平均着床数减少,平均早期死亡胚胎数增加。     

子宫增重法检测壬基酚、双酚A雌激素样活性及其联合作用

目的应用子宫增重法检测壬基酚(NP)、双酚A(BPA)的雌激素样活性并评价其联合作用。方法选择性未成熟雌性昆明种小鼠110只,体重10~13g,按体重随机分为11组:NP240mg/kg、120mg/kg、60mg/kg剂量组,BPA480mg/kg、240mg/kg、120mg/kg剂量组,联合240mg/kgBPA 120mg/kgNP、120mg/kgBPA 60mg/kgNP、60mg/kgBPA 30mg/kgNP剂量组,阴性对照组、阳性对照组(苯甲酸雌二醇1·47μg/10g),皮下注射染毒3d,称子宫湿重,计算子宫重量系数。用金正均法评价联合作用的性质。结果NP和BPA可致子宫重量系数增大,呈剂量-效应关系(分别为r=0·8192,P<0·01;r=0·6898,P<0·01);两者联合染毒致子宫重量系数增大,亦呈剂量-效应关系(r=0·5465,P<0·01)。各染毒组与阴性对照组比较,差异有统计学意义(P<0·05或P<0·01),其联合作用性质在混合低剂量组呈协同作用(Q=1·41),混合中、高剂量组呈相加作用(Q=0·88,Q=0·87)。结论NP、BPA具有雌激素样活性,其联合作用性质在较低剂量呈协同作用,较高剂量呈相加作用。     

邻苯二甲酸(2-乙基己基)酯对雄性小鼠的生殖毒性

为探讨邻苯二甲酸(2-乙基己基)酯[di(2-ethylhexyl)phthalate,DEHP]对小鼠的生殖毒性.将30只成年健康SPF级雄性昆明小鼠随机分成5组,分别为阴性对照(玉米油)组和低(1 250 mg/kg)、中(2 500 mg/kg)、高剂量(5000mg/kg)DEHP染毒组以及阳性对照(环磷酰胺40 mg/kg)组,每组6只.除阳性对照组采用腹腔染毒外,其余各组采用经口灌胃方式进行染毒,染毒容量为0.02 ml/g,每天1次,连续染毒5d.于首次染毒5周后,采用一般生殖毒性实验方法对精子计数和精子存活率、畸形率、活动率进行测定.结果显示,与阴性对照组比较,各剂量DEHP染毒组小鼠精子计数和精子存活率均较低;而中、高剂量DEHP染毒组精子畸形率较高,活动率较低,差异均有统计学意义(P＜0.05).随着DEHP染毒剂量的升高,小鼠精子计数和活动率、精子存活率均呈下降趋势,精子畸形率呈上升趋势.提示DEHP对雄性小鼠具有一定的生殖毒性.     

苯对大鼠的生殖毒性和胚胎发育毒性研究

目的探讨苯对大鼠的生殖毒性和胚胎的体内发育毒性。方法以浓度分别为0、5、10、15mg/m3的苯给雌雄性大鼠静式吸入染毒,观察雄性大鼠精子畸形和雌雄交配受孕情况、受精卵着床数、活胎数、死胎数、吸收胎数及胚胎的生长发育情况。结果苯染毒组大鼠精子畸形率高于空白对照组,随着苯染毒浓度的增加,畸形率有增加(P0.05);与空白对照组比较,中、高剂量苯染毒可抑制胎盘和胎仔生长发育,吸收、死胎发生率增加(P0.05)。结论苯具有雄性生殖毒性,并对胚胎有一定的致畸性作用和发育毒性。     

甲胺磷对小鼠精子质量的影响

目的：研究甲胺磷对小鼠精子质量的影响。方法：用不同剂量（0．5,3．75,5．0,7.5mg/kg）的甲胺磷经腹腔注射染毒BALB／C雄性小鼠,4周后对小鼠精子数量,精子活率和精子形态进行分析。结果：染毒组小鼠精子畸形率与对照组相比显著增加,除0．5mg/kg剂量组外,其他剂量组小鼠精子活率显著下降,与对照组相比有统计学意义,5．0和7．5mg/kg剂量组小鼠精子数量明显低于对照组,结论：甲胺磷对小鼠精子有一定毒性。     

几种药剂对家蝇和德国小蠊毒力研究

目的研究室内条件下，几种杀虫剂对家蝇及德国小蠊敏感品系的毒力。方法点滴法。结果阿维菌素对家蝇成虫的毒力最强，LD50为0．004μg／♀，阿维菌素对家蝇的毒力分别为氟虫腈、高效氯氰菊酯、多杀菌素、茚虫威与虫螨腈的3．0、3．5、13．8、30．0、40．0倍。药剂对德国小蠊毒力测定结果表明，氟虫腈对德国小蠊的毒力最强，LD50为0．004μg/♂，其次为阿维菌素、高效氯氰菊酯，LD50分别为0．005、0．009μg/♂，而多杀菌素、茚虫威与虫螨腈毒力相对较差。氟虫腈对家蝇的毒力分别为阿维菌素、高效氯氰菊酯、多杀菌素、虫螨腈与茚虫威的1．3、2．3、30．0、102．5、692．5倍。结论这些杀虫剂对家蝇及德国小蠊具有较好的防治效果。     

丙烯腈对雄性小鼠的生殖毒性作用

目的探讨丙烯腈的雄性生殖毒作用机制。方法以雄性小鼠为研究对象,腹腔注射染毒,流式细胞仪检测分析不同观察终点、不同染毒剂量对小鼠睾丸组织各倍体细胞、各时相生精上皮细胞的影响。结果丙烯腈影响次级精母细胞、精子细胞和精子的形成,主要作用于生精上皮细胞的有丝分裂期;丙烯腈诱导雄性小鼠生精细胞凋亡,随着染毒剂量的增加和时间的延长,凋亡发生率增高,第21天的各染毒组细胞凋亡最明显(P<0.05)。结论丙烯腈具有明显的雄性生殖毒性,干扰精子形成。     

口服Vit C及Vit E对缓解骨髓移植术相关毒性的临床观察

目的 研究补充抗氧化性维生素对于增强骨髓移植患者血浆总抗氧化力(TAC)，降低脂质过氧化(MDA)，缓解移植术相关毒性的作用。方法 随机、单盲设计，选择20例骨髓移植患者随机分为2组，实验组于预处理前给予Vit C(300mg／d)及Vit E(600mg／d)，对照组不予补充，其余处理两者同。测定移植前后两组患者血浆TAC、MDA以及血胆红素、肌酐、L-乳酸脱氢酶的浓度，观察并记录两组患者口腔溃疡(OM)的发生及其程度。结果 (1)移植前后实验组TAC值一直处于正常或高于正常对照值，对照组则低于正常，两者有显著差异；移植后对照组MDA值与实验组有显著差异，实验组移植后很快降至正常，对照组一直处于较高水平。(2)实验组患者在OM的发生及程度上、心肌毒性、肝脏毒性指标上与对照组有差异；在肾脏毒性指标方面两组患者无差异。结论 移植前外源性补充抗氧化性维生素可提高骨髓移植患者机体的抗氧化力，减少脂质过氧化物的产生，有效缓解移植术后部分相关毒性。     

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.     

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.