大蒜素对小鼠辐射损伤的辅助保护作用

目的 研究大蒜素对小鼠辐射损伤的辅助保护作用.方法 将60只昆明雄性小鼠随机分为辐射模型对照组、溶剂对照组、大蒜素低(0.17 g/kg)、中(0.33 g/kg)、高(1.00 g/kg)剂量组,用大蒜素灌胃20 d后,小鼠接受60Co-γ射线一次性全身辐照,观察对小鼠外周血白细胞总数、骨髓细胞微核率、骨髓细胞DNA含量、红细胞超氧化物歧化酶(SOD)活力等损伤指标的影响.结果 大蒜素高剂量组能明显增加经一次60Co-γ射线全身照射后小鼠的外周血白细胞总数,降低骨髓细胞微核发生率,提高骨髓细胞DNA含量,增加红细胞超氧化物歧化酶(SOD)的活力.结论 大蒜素对小鼠辐射损伤有辅助保护作用.     

枸杞多糖对慢性辐射小鼠细胞凋亡及bcl-2基因表达的影响

目的：探讨枸杞多糖(LBP)对辐射小鼠细胞凋亡及凋亡相关基因bcl-2表达的影响。方法：以水提取-乙醇沉淀法制备枸杞多糖，并制成0．8％的饲料，给予受试小鼠(枸杞多糖组)。正常对照组、辐射对照组给予普通饲料。除正常对照组外，另两组均用^60Coγ射线对动物进行全身性照射，每天照射1次，每天照射剂量为0.084Gy，每周照射5d，连续照射6w，照射总剂量为2.52Gy。检测骨髓微核率、睾丸精母细胞染色体畸变、精子畸形率、肝细胞caspase-3 mRNA表达水平、细胞凋亡及凋亡相关基因bcl-2表达等指标。结果：LBP可使辐射引起的微核率、染色体畸变、及精子畸形率显降低，骨髓细胞增殖活性提高，凋亡率降低，使辐射小鼠bcl-2基因表达提高、caspase-3 mRNA表达水平降低。结论：枸杞多糖的抗辐射作用与其调控细胞bcl-2基因表达，影响细胞凋亡有关。     

莲房原花青素对~(60)Co-γ射线致亚急性辐射损伤防护的研究

目的:研究莲房原花青素(LSPC)的抗辐射作用。方法:80只小鼠分4组,实验组分别连续灌胃不同剂量(50、100、200mg/kgbw)的LSPC15d后,接受60Co-γ射线8.0Gy照射后,一半动物观察平均存活时间和30d存活率。另一半动物于照射后不同时间检测外周血白细胞、红细胞、血小板、血红蛋白含量。结果:小鼠经8.0Gy60Co-γ一次全身辐照后,100、200mg/kgbwLSPC组能使小鼠平均存活时间分别提高49.2%和58.3%,存活率明显高于对照组,且各组小鼠的保护指数均大于1.0;外周血像于照后21d基本恢复正常,且以200mg/kgbwLSPC组效果最佳。结论:LSPC对8.0Gy60Co-γ射线亚急性辐射损伤有一定的保护作用。     

银杏叶黄酮抗辐射效应研究

目的:研究银杏叶中黄酮的抗辐射作用。方法:以碱性水提取法从银杏叶中分离出总黄酮(GBF),调配成低剂量(10 mg/100 ml)、中剂量(20 mg/100 ml)、高剂量(100 mg/100 ml)水溶液,分别给小鼠灌胃,10 d后,以总剂量8.5 Gy 60Co-γ射线整体辐射,再灌胃10 d,观察30 d存活率。另取小鼠,分六组(低、中、高GBF剂量组,辐射对照组,正常对照组,及环磷酰胺组),分别灌胃低、中、高剂量GBF水溶液,另三组灌胃蒸馏水,连续11 d后,低、中、高剂量GBF组及辐射对照组以总剂量1.0 Gy γ射线照射,再灌胃7 d,灌胃停止后D21 测小鼠骨髓微核率及精子畸变率及淋巴细胞测转化率。结果:低、中、高剂量GBF水溶液可分别提高辐射小鼠存活率31.7 %,25.3 %和26.5 %( P<0.05),低剂量GBF使淋巴细胞转化率显著提高(P<0.01),骨髓微核率及精子畸变率有一定程度降低。结论:低剂量银杏叶黄酮具有较强的抗辐射作用,其作用机制与提高小鼠免疫力有关。     

枸杞多糖对慢性辐射小鼠细胞凋亡及bc1-2基因表达的影响

目的:探讨枸杞多糖(LBP)对辐射小鼠细胞凋亡及凋亡相关基因bcl-2表达的影响。方法:以水提取-乙醇沉淀法制备枸杞多糖,并制成0.8%的饲料,给予受试小鼠(枸杞多糖组)。正常对照组、辐射对照组给予普通饲料。除正常对照组外,另两组均用60Coγ射线对动物进行全身性照射,每天照射1次,每天照射剂量为0.084Gy,每周照射5d,连续照射6w,照射总剂量为2.52Gy。检测骨髓微核率、睾丸精母细胞染色体畸变、精子畸形率、肝细胞caspase-3mRNA表达水平、细胞凋亡及凋亡相关基因bc1-2表达等指标。结果:LBP可使辐射引起的微核率、染色体畸变、及精子畸形率显著降低,骨髓细胞增殖活性提高,凋亡率降低,使辐射小鼠bc1-2基因表达提高、caspase-3mRNA表达水平降低。结论:枸杞多糖的抗辐射作用与其调控细胞bc1-2基因表达,影响细胞凋亡有关。     

苹果提取物抗辐射效应的研究

目的 :　研究苹果提取物的组成成分及其抗辐射效应。方法 :　利用分光光度法及HPLC法分析苹果提取物中酚类物质 ,并采用灌胃方式给予实验小鼠 ,连续灌胃 30 d后接受 7Gy60 Co-γ射线一次性辐照 ,照射后一半动物取血进行白细胞计数 ,另一半动物观察平均存活时间和 30d存活率。结果 :　 (1 )苹果提取物中主要的酚类成分为原花青素低聚体 ,儿茶素单体 ,酚酸 ,黄酮等酚类物质。 (2 )灌胃高剂量苹果提取物 30 d的小鼠经 7Gy一次性辐射后 ,第 7d小鼠白细胞数量比辐射对照组提高了 1 1 2 % (P<0 .0 1 ) ,第 1 4 d小鼠白细胞数量提高了 52 % (P<0 .0 5) ;且苹果提取物高剂量组小鼠的 30 d存活率明显高于辐射对照组 (P<0 .0 5)。 (3)服用中、高剂量的小鼠比辐射对照组平均存活天数分别提高了 72 % (P<0 .0 1 )和 69% (P<0 .0 1 )。结论 :　苹果提取物对 7Gy剂量一次性照射具有拮抗作用。其主要成分可能为原花青素低聚体 ,儿茶素等酚类物质。     

灵芝黄芪口服液的抗辐射功能研究

目的研究灵芝黄芪口服液的抗辐射功能,为其应用提供相应的指导。方法共选取SPF级ICR雌性小鼠180只,分为3组。以3.3、6.7、20.0ml/kg·bw的灵芝黄芪口服液连续灌胃小鼠30d后,第Ⅰ组以4Gy剂量的60 Co-γ射线照射1次,3d后测定骨髓细胞DNA含量;第Ⅱ组以7Gy剂量的60 Co-γ射线照射1次,7d后测定血清中超氧化物歧化酶(SOD)活性;第Ⅲ组以2Gy剂量的60 Co-γ射线照射1次,7d后检测血清溶血素水平。结果灵芝多糖口服液能增加小鼠骨髓细胞DNA含量、提高血清中超氧化物歧化酶(SOD)活性。结论灵芝多糖口服液具有抗辐射损伤的作用。     

油菜花粉酶解肽抗辐射损伤的研究

目的研究油菜花粉酶解肽(CPRP)的抗辐射损伤作用,为开发安全低毒的抗辐射药物和提高花粉的其它效应提供理论依据。方法将昆明种小鼠随机分为正常对照组、辐射对照组、维生素C(VC)对照组、CPRP低、中、高剂量组。正常对照组与辐射对照组以生理盐水灌胃,VC组以100mg/kgbwVC水溶液灌胃,低、中、高剂量CPRP组分别以50、100、150mg/kgbw的CPRP溶液灌胃,1次/d,连续灌胃35d。在14d时进行4Gy60Co-γ射线一次性辐射。灌胃结束后杀死动物,检测小鼠外周血白细胞数、肝脏组织中超氧化物歧化酶(SOD)活性、骨髓细胞DNA含量和脏器指数。结果CPRP能在规定实验条件下阻止由辐射引起的小鼠外周血白细胞数下降,SOD活性增强,并使小鼠骨髓细胞DNA含量和胸腺脾脏指数升高。在三个剂量组中以高剂量组效果最好。结论CPRP具有良好的抗辐射作用。     

灵芝抗辐射功能的研究

目的 探讨灵芝的抗辐射作用。方法 以0．25，0．50，1．50g/kg体重的灵芝精粉混悬液连续给小鼠灌胃60天，在第30天以射线照射小鼠，观察小鼠的白细胞总数、30天存活率、平均存活时间。结果 灵芝精粉能使辐射后小鼠30天存活率明显增高、平均存活时间延长、白细胞总数明显增加。结论 灵芝具有抗辐射损伤作用。     

六珍双抗胶囊抗辐射实验研究

目的 实验研究六珍双抗胶囊的抗辐射作用。方法 选取昆明种雄性小鼠,随机分成辐射对照组及高、中、低、三个用药剂量组,按照38 mGy/d的剂量连续照射92 d,观察小鼠骨髓嗜多染红细胞的微核率,以及小鼠染色体畸变率。结果 实验组与对照组比较,小鼠微核率与睾丸染色体畸变率均显著低。结论 六珍双抗胶囊具有抗辐射作用。     

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.     

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.     

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.     

Investigating clusters in the workplace and beyond

Clusters of disease are common and occur in the workplace and in the general community. They often arouse considerable concern among the population. Investigations have sometimes lead to exciting new knowledge, but in general the investigation of clusters is difficult and often unrewarding, especially for community clusters. In the workplace, investigations are more likely to find associations and even new causes, but still many clusters remain enigmatic. Despite this, there are many reasons for investigating clusters, including allaying community concern and identifying uncontrolled exposures. A structure for investigating clusters in the workplace is suggested.