方格星虫多糖对5.0Gy ^60Coγ辐射损伤小鼠的保护作用

目的观察方格星虫多糖对亚致死剂量60Coγ射线照射小鼠的保护作用。方法将60只雄性C57BL/6J小鼠随机分为正常对照组、模型组、尼尔雌醇组及低（100 mg/kg·d）、中（200 mg/kg·d）、高（400 mg/kg·d）三个剂量方格星虫多糖组,每天一次灌胃给药,尼尔雌醇组照射前一天给予尼尔雌醇3.3 mg/kg灌胃,照射后0.5 h再次给予1.67 mg/kg尼尔雌醇灌胃。灌胃2 w后,除正常对照组外,各组均以剂量率为0.8 Gy/min的60Coγ射线全身照射一次,照射剂量为5.0 Gy。于辐照后3 d、14 d测定小鼠体重、外周血WBC,辐照后14 d测定小鼠胸腺指数,脾指数,骨髓细胞和脾细胞DNA含量,血清SOD和MDA含量。结果γ射线全身照射后第3天,方格星虫多糖低、中剂量组小鼠外周血WBC数明显升高（P〈0.05）。照后第14天,低剂量组小鼠外周血WBC数显著增高（P〈0.01）,中、高剂量组脾脏重量指数明显升高（P〈0.01和P〈0.05）,中剂量组脾脏DNA含量明显增高（P〈0.01）;低、中剂量组骨髓细胞DNA含量明显增高（P〈0.05）;低、中、高三个剂量组小鼠血清SOD活力明显增强,血清MDA含量明显下降（P〈0.05）。结论方格星虫多糖对亚致死剂量γ辐射损伤小鼠具有一定保护作用。     

西洋参多糖对钴-60辐照小鼠的免疫调节作用

目的探讨西洋参多糖对钴-60γ射线照射致小鼠免疫抑制模型的免疫调节作用,并初步探讨其作用机制。方法将180只6～8周龄、18～22 g的雌性BALB/c小鼠随机分为5组:空白对照组、模型对照组和3个西洋参多糖剂量组(50mg/kg BW、100mg/kg BW和200mg/kg BW)。除空白对照组外,其余4组于d45,一次性接受全身照射(γ射线总剂量为4Gy)。3 d后,测定脾脏T淋巴细胞增殖能力、迟发型变态反应程度和碳粒廓清实验,测定血清丙二醛水平、超氧化物歧化酶活性和谷胱甘肽过氧化物酶活性。结果西洋参多糖在3个剂量组均能明显升高小鼠T淋巴细胞的增殖能力和迟发型变态反应程度,在100mg/kg BW和200mg/kg BW组能明显增高小鼠碳粒廓清指数,在3个剂量组均能明显降低小鼠血清中MDA水平,在50mg/kg BW组能明显增高小鼠血清SOD活性,小鼠血清GSH-Px活性差异无统计学意义。结论西洋参多糖能增强钴-60γ射线照射致免疫抑制小鼠免疫功能,可能通过减轻氧化应激对免疫系统的损害来实现。     

锌对全身照射小鼠骨髓造血细胞辐射损伤的影响

[目的]探讨锌对γ射线诱发小鼠骨髓细胞辐射损伤的影响。[方法]小鼠按随机区组法分为空白对照组、辐射对照组以及3个加锌实验组。加锌组分别按每kg普通饲料加入30mg、60mg、120mgZn^2＋后喂饲两周，两对照组喂饲普通饲料。之后除空白对照组外，其余各组均以6Gy^60Coγ射线进行全身照射，2d后处死动物。分别测定外周血白细胞数、骨髓有核细胞数和DNA含量、骨髓细胞超氧化物歧化酶（SOD）活力和丙二醛（MDA）含量以及微核率。[结果]^60C0γ射线照射小鼠后2d，外周血白细胞数、骨髓有核细胞数和DNA含量均显著下降，细胞SOD活力下降而MDA含量升高，微核率升高；饲料中加入30～120mg／kg的锌，能使以上辐射损伤得到明显缓解。[结论]饲料中加锌对小鼠骨髓细胞具有辐射损伤防护作用。     

牦牛活性蛋白对X射线损伤小鼠的防护作用

目的探讨牦牛活性蛋白对辐射损伤小鼠的防护作用。方法健康昆明小鼠60只,随机分为正常对照组、模型组、阳性组(氨磷汀,150 mg/kg)、牦牛活性蛋白高、中、低剂量(10、5、2.5 mg/kg)6组。辐射前牦牛活性蛋白给药组连续灌胃14 d,正常组和模型组灌胃给予等容生理盐水,阳性组于照射前30min腹腔注射给药。除正常组外,其它实验组用X射线全身一次性照射,照射剂量5Gy,照射后第7 d观察牦牛活性蛋白对小鼠外周血象、抗氧化酶活力、脏器指数、骨髓DNA、白介素2(IL-2)、白介素6(IL-6)含量及B细胞淋巴瘤因子2(Bcl-2)、Bcl-2相关X蛋白(Bax)表达情况。结果牦牛活性蛋白对辐射后小鼠脏器指数有明显升高作用,血象有明显上升现象,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)、总抗氧化力(T-AOC)活力明显增强,丙二醛(MDA)含量显著降低,骨髓DNA、IL-2含量显著升高,Bcl-2表达升高,Bax表达下降。结论研究结果表明,牦牛活性蛋白对X射线所致小鼠辐射损伤有一定的改善和保护作用。     

慢性低剂量辐射小鼠模型的建立与评价

目的比较不同剂量X射线照射后实验小鼠生物学指标的变化,以建立辐射损伤动物模型。方法用三种辐射剂量率(0.04 Gy/h/d、0.08 Gy/h/d、0.12 Gy/h/d)的X射线对三组昆明小鼠(辐射剂量由低到高分为L、M、H组)进行连续7天全身照射,同时设立不接受辐射的对照组(NC),辐射后检测各组小鼠脏器指数、外周血细胞计数、骨髓有核细胞计数、血清MDA含量和SOD活性等指标的变化,同时比较辐射前后各组小鼠体质量和肝脏、脾脏指数的改变。结果照射后7天,L组小鼠体质量明显低于NC组以及M、H组(P0.05); M、H组小鼠脾脏指数显著低于NC组(P0.01)和L组(P0.05);不同剂量辐射组小鼠外周血WBC和骨髓有核细胞数量均较NC组显著降低(P0.05,P0.01);与NC组比较,M组小鼠血清MDA含量显著升高(P0.05)、SOD活性显著降低(P0.05)。结论慢性累积性低剂量辐射小鼠模型的最佳造模方法为辐射剂量率0.08 Gy/h/d、连续辐射7天,累积辐射剂量0.56 Gy。     

灰树花多糖免疫调节及抗辐射损伤作用研究

目的观察灰树花多糖对小鼠免疫功能和辐射损伤的影响。方法将小鼠随机分为溶剂对照组和3个试验剂量组,剂量分别为0.15g/kg、0.30g/kg、0.90g/kg,每天灌胃給予,连续30d后,检测7项免疫指标。另取小鼠,按体重随机分为辐射对照组和3个试验剂量组,剂量设计和给药方式同上,30d后,各组均以~(60)Co-γ射线进行一次全身照射,根据检测指标选择不同的照射剂量。辐照前、辐照后第3和14天进行外周血白细胞计数;辐照后第3天进行骨髓细胞DNA含量检测:辐照后第7天进行血清超氧化物歧化酶(SOD)活力测定。结果灰树花多糖能显著提高小鼠的抗体生成细胞数和血清溶血素水平,ConA诱导的脾淋巴细胞增殖能力和NK细胞活性明显增强,碳廓清指数、腹腔巨噬细胞吞噬指数明显高于对照组。灰树花多糖能显著提高受~(60)Co-γ射线照射小鼠的外周血白细胞数和骨髓细胞DNA含量,明显增强血清超氧化物歧化酶(SOD)活力。结论灰树花多糖能增强小鼠的细胞免疫和体液免疫功能以及单核-巨噬细胞吞噬功能,对辐射损伤具有一定的防护作用。     

Radaway抗辐射胶囊对小鼠辐射损伤的保护作用

目的 观察Radaway抗辐射胶囊对小鼠γ射线辐射损伤的保护作用。方法 将120只雄性昆明小鼠随机分为I(外周血白细胞计数)、Ⅱ(骨髓细胞微核检测)、Ⅲ(骨髓DNA含量测定)3大组,每大组又随机分为高、中、低剂量组和辐射对照组。各组根据不同指标选择不同的照射时间均以同一剂量γ射线全身照射1次。结果 以3Gy剂量照射后第14天各剂量组的外周血白细胞计数均显著高于辐射对照组(P < 0.01);照射后第3天,中、低剂量组的骨髓细胞微核率显著低于辐射对照组(P < 0.01),低剂量组的骨髓DNA含量显著高于辐射对照组(P < 0.01)。结论 Radaway抗辐射胶囊对小鼠γ射线辐射损伤具有显著的保护作用。     

羊栖菜多糖复方对雄性小鼠免疫及生殖器官辐射伤的防护

目的观察羊栖菜多糖复方制剂对γ射线损伤雄性小鼠免疫器官及生殖器官的防护作用。方法将50只雄性小鼠随机分为正常对照组、模型组及低〔0.692 g/(kg.d)〕、中〔2.075 g/(kg.d)〕、高〔4.150 g/(kg.d)〕3个剂量羊栖菜多糖复方制剂组(SFPCP),每天1次灌胃给药,灌胃2周后,除正常对照组外,各组均以剂量率为0.83 Gy/h的60Coγ射线进行1次全身照射6 h,照射剂量为5 Gy。于照前1 d,照后3 d、14 d测定外周血白细胞数,照后14 d测定小鼠胸腺指数、脾指数、骨髓有核细胞数(BMNC)、睾丸质量指数、精子总数及精子畸形率。结果照后14 d,中剂量给药组外周血白细胞数为(1.4±0.2)×109/L,明显高于模型组(1.0±0.5)×109/L(P<0.05);照后14 d,低、中、高3个剂量组小鼠的胸腺指数分别为(2.21±0.63)mg/g、(2.10±0.43)mg/g及(2.03±0.32)mg/g,明显高于模型组的(1.58±0.58)mg/g(P<0.05),中、高剂量组的脾指数和骨髓有核细胞数显著高于模型组的(P<0.05);中、高剂量组睾丸质量指数分别为(3.55±0.30)mg/g和(3.57±0.31)mg/g,明显高于模型组(3.26±0.30)mg/g(P<0.05),低、中、高剂量组精子总数分别为(17.5±6.2)×104,(19.0±7.0)×104和(20.8±11.4)×104,明显高于模型组(12.2±7.4)×104(P<0.05),中、高剂量组的精子畸形率显著低于模型组(P<0.05,P<0.01)。结论羊栖菜多糖复方制剂对小鼠的免疫器官及生殖器官的辐射损伤具有一定的保护作用。     

大豆复合物对γ射线辐射损伤防护作用

目的探讨大豆复合物对γ射线照射小鼠的辐射防护效应。方法清洁级雄性昆明小鼠分3批,每批按体重随机分为假照射组、照射模型组、大豆复合物低剂量组及大豆复合物高剂量组。各受试物组小鼠经口灌胃各组受试物,连续30d后用60Co-γ射线进行1次全身照射,照射后仍然给予受试物。第1批实验除假照射组外,均以3.0Gy照射剂量γ射线全身照射1次,分别于照射后第3d,第14d检测外周血白细胞数。第2批实验除假照射组外,均以5.0Gy剂量全身照射1次,于照射后第3d测定骨髓有核细胞数和骨髓细胞微核率。第3批实验除假照射组外,均以7.0Gy剂量全身照射1次,于照射后第7d,测定红细胞与肝脏超氧化物歧化酶（SOD）活性和丙二醛（MDA）含量。结果（1）照射后第3d和第14d,大豆复合物高剂量组和低剂量组小鼠的外周血白细胞数分别高于照射模型组（P〈0.05）;（2）各受试物组小鼠的骨髓有核细胞数均高于照射模型组（P〈0.05）,骨髓细胞微核率低于照射模型组（P〈0.05）;（3）与照射模型组比较,不同剂量的大豆复合物均可明显提高小鼠红细胞和肝脏SOD活性（P〈0.05）,降低血浆MDA水平（P〈0.05）。结论大豆复合物能在一定程度上阻止由辐射引起的外周血白细胞和骨髓有核细胞数下降,减少微核产生,提高受照射小鼠的抗氧化能力,减轻辐射对机体的损伤。     

葡萄籽提取物抗电离辐射的实验研究

目的研究葡萄籽提取物抗电离辐射的作用。方法将SPF级雄性昆明种小鼠随机分为3个剂量组(0.25、0.50、1.50g/kg Bw)和1个辐射模型对照组,给小鼠连续灌胃受试物21天后用γ射线全身照射一次,照射后继续给受试物至实验结束,观察小鼠的外周血白细胞计数、骨髓有核细胞、骨髓细胞微核率、血清超氧化物歧化酶(SOD)活性及血清半数溶血值(HC50)的变化。结果以3GY的γ射线照射后,第3天1.50g/kg Bw组的外周血白细胞计数和骨髓有核细胞明显高于辐射模型对照组(P0.05),而骨髓细胞微核率明显低于模型对照组(P0.05),第14天1.50、0.50g/kg Bw组的外周血白细胞计数明显高于对照组(P0.05);以6GY的γ射线照射后,第7天1.50g/kg Bw组小鼠的血清SOD活性明显高于对照组(P0.05);以2GY的γ射线照射后,第14天各剂量组小鼠的血清HC50与对照组比较,差异无显著性(P0.05)。结论该葡萄籽提取物对辐射危害具有一定的辅助保护功能。     

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.