有机硒对大鼠胸部γ射线照射所致肺损伤的防护效应

目的研究有机硒对大鼠放射性肺损伤的防护作用。方法取2月龄雌性Wistar大鼠45只,随机分为正常对照组(C)、单纯照射组(I)和硒防护组(S),每组15只。S组动物在60Coγ(20 Gy)照射前7 d灌胃给富硒麦芽,用量为每只每天4 000 mg.kg-1。C组和I组动物灌胃同体积的蒸馏水,于照射当天停止给药。在不同时间点处死动物称鼠重、鲜肺湿重,测肺组织MDA含量及SOD、GSH-PX活力。结果照射后15 d3、0 d、60 d时,S组体重增长百分率都明显高于I组,如60 d时两组分别为(43.9±0.3)%和(18.5±0.2)%(P<0.05);照射后15 d3、0 d时,S组肺湿重有低于I组的趋势;照射后15 d,S组MDA含量〔(16.64±0.65)nmol.mg pro-1〕明显低于I组〔(24.24±2.61)nmol.mg pro-1,P<0.05〕,S组SOD活力〔(75.69±3.72)NU.mg pro-1〕明显高于I组〔(52.03±6.43)NU.mg pro-1,P<0.05〕;S组GSH-Px活力有高于I组的趋势。结论补硒对放射性引起的肺损伤有一定的防护作用。     

富硒米喂养的大鼠全血硒水平

目的 :探讨富硒米喂养的大鼠全血硒水平与免疫功能的关系 ,为富硒米用于防癌保健提供科学根据。方法 :30天喂养试验 :2、3-二氨基萘荧光分析法测全血硒水平 ;3 H- Td R掺入液闪法检测淋巴细胞转化。结果 :低、中、高剂量组及对照组的大鼠全血硒水平分别为 0 .575± 0 .1 54,0 .686± 0 .2 0 6,0 .894± 0 .1 80 ,0 .479± 0 .0 88μg/ml,且中、高剂量组显著性地高于对照组( P<0 .0 5,P<0 .0 1 ) ;低、中、高剂量组的淋巴细胞转化分别为 0 .762± 0 .461 ,0 .887± 0 .474,0 .791± 0 .539,0 .42 4± 0 .2 2 1 cpm万 /1 0 6细胞 ,且中剂量组显著性地高于对照组 ( P<0 .0 5) ;受试动物进食、活动等正常 ,动物体重、血常规亦正常 ,未见动物中毒和死亡情况。结论 :富硒米可提高受试动物的全血硒水平 ,血硒水平的提高有利于增强机体的免疫功能。富硒米不引起动物中毒和死亡 ,提示富硒米为无毒食品 ,可用于防癌保健。     

长波脉冲电磁场对作业人员血流动力学参数的影响

目的 :　研究长波脉冲电磁场对作业人员健康的影响 ,为制订防护措施提供依据。方法 :受试者为 71名海军指战员 ,分为暴露组 (4 1人 )和对照组 (30人 )。以脉图法研究了某导航台长波脉冲电磁场对两组人员血流动力学参数的影响。结果 :暴露组的脉率 (P)为 (71.4±12 .4 )b·min- 1、微循环半更新率 (ALK)为 0 .0 4 6± 0 .0 11、心肌氧耗指数 (HOI)为 1683± 4 75 ,均分别较对照组的 (81.6± 10 .5 )b·min- 1、0 .0 5 4± 0 .0 0 7、195 9± 368非常显著降低 (P <0 .0 1)。此外 ,暴露组的平均收缩压为 (13.5 3± 1.5 9)kPa、平均舒张压为 (10 .5 9± 1.36)kPa、平均动脉压为(12 .0 8± 1.4 5 )kPa、主动脉排空系数 (BK)为 (0 .2 0 8± 0 .0 63)、左心有效泵力指数 (VPeI)为 (799±192 )N·min- 1·m- 2 也分别较对照组的 (14.99± 1.4 5 )kPa、(11.36± 1.39)kPa、(12 .92± 1.4 4 )kPa、(0 .2 4 8± 0 .0 81)kPa、(90 5± 12 5 )N·min- 1·m- 2 显著降低 (P <0 .0 5 )。结论 :长波脉冲电磁场对作业人员血流动力学参数有一定影响 ,呈现心血管功能减弱状态。     

长波紫外线对大鼠皮肤脂质过氧化和胶原的影响及防晒剂的防护

[目的 ]　探讨长波紫外线 (UVA )对大鼠皮肤脂质过氧化和胶原合成的影响及防晒化妆品的防护效果。　[方法 ]　UVA照射组和涂抹防晒化妆品组大鼠经UVA照射 8周后 (总计量为 30 6 1.8J/cm2 ) ,测定皮肤丙二醛 (MDA)、超氧化物歧化酶 (SOD)、总胶原和可溶性胶原的含量。　 [结果 ]　UVA照射组大鼠皮肤MDA(11.36± 1.92nmol/mL)高于对照组 (7.0 3± 1.11nmol/mL) (P <0 .0 1) ,高于防晒化妆品组 (8.0 5± 1.2 8nmol/mL) (P <0 .0 1)。UVA照射组总胶原(2 5 .98± 3.0 6mg/g)低于对照组 (31.36± 3.99mg/ g) (P <0 .0 5 ) ,与防晒化妆品组 (2 8.71± 3.72mg/ g)差异无显著性 (P>0 .0 5 )。UVA照射组可溶性胶原 (4.2 5± 0 .83mg/ g)低于对照组 (6 .33± 1.19mg/g) (P <0 .0 1) ,低于防晒化妆品组(5 .70± 1.14mg/g) (P <0 .0 5 )。对照组、UVA照射组和防晒化妆品组的SOD分别为 18.6 9± 2 .82 U/mL、16 .40± 2 .14U /mL、17.86± 2 .95U/mL ,三者差异没有显著性 (P >0 .0 5 )。　 [结论 ]　UVA能使皮肤脂质发生过氧化和降低皮肤可溶性胶原的含量 ,防晒化妆品有一定的防护效果。     

低温海水淹溺濒临死亡大鼠动物模型的研究

目的建立低温海水淹溺濒临死亡动物模型,为开展相关研究奠定理论基础.方法将大鼠置于16℃～18℃低温海水中,自由游动,直至沉入水底;迅速取出动物,置室温下于不同时间(1、5、15、30及60min)观察生命指征,快速自左心室取血1ml行血气分析,处死动物,取左肺计算干湿重比值,透射电镜观察右肺超微结构.结果动物入海水后约15min呼吸暂停;出海水后肛温、肺干湿重比值、呼吸频率和心率明显降低,1min组呼吸频率达最低点(47±7)次/min,心率(70±14)次/min;5min组肛温降至最低点(20.25±0.52)℃,上述指标除肺干湿重比值外均呈上升趋势,60min组呼吸频率达(111±26)次/min、心率达(177±28)次/min,接近正常对照组水平,差异无显著性(P＞0.05),而肛温(23.82±0.72)℃和肺干湿重比值(0.08±0.03)仍未达正常对照组水平,差异有显著性(P＜0.01).血pH、动脉氧分压(PaO2)及血氧饱和度(SaO2)明显降低,5min组降至最低点[6.67±0.11、(5.91±2.98)kPa、43.30%±15.03%],随后呈上升趋势;60min组血PaO2(11.81±1.45)kPa及SaO2(88.63%±14.39%)接近正常对照组水平,差异无显著性(P＞0.05),而血pH(7.10±0.14)仍未达正常对照组水平,差异有显著性(P＜0.01).5min及15min组二氧化碳分压(PaCO2)明显升高,5min组升至最高点(13.18±1.88)kPa,差异有显著性(P＜0.01),随后呈恢复趋势,30min组[(8.72±2.72)kPa]及60min组[(8.91±1.54)kPa]接近正常对照组水平,差异无显著性(P＞0.05).肺脏呈"湿肺”改变;12只动物出海水约15min死亡.结论成功建立大鼠低温海水淹溺濒临死亡动物模型;动物死亡多发生在出海水15min左右,主要死于低氧血症和酸中毒.     

经肠道补充精氨酸对严重烧伤家兔免疫功能的影响

目的 :研究精氨酸对烧伤家兔免疫功能的影响及其机制。　方法 :采用 30 %体表面积三度烧伤家兔模型。将 2 6只日本长耳白兔随机分成三组 :即正常对照组 (n =8)、烧伤对照组 (n =9)和精氨酸喂养组 (n =9)。精氨酸组给予醋酸精氨酸 1.2g/ (kg·d) (精氨酸净重 0 .89g) ,烧伤对照组给予等量的酪氨酸 ,观察给药 7天后精氨酸对烧伤家兔免疫功能的影响。　结果 :烧伤 7天后两组动物免疫功能均明显下降 ,两组相比 ,精氨酸组家兔免疫功能明显优于烧伤对照组 ,各项免疫指标的变化均有显著意义 ,淋巴细胞转化率为 (5 8.4 4± 5 .2 0 ) %vs.(48.0 0± 3.2 8) % ,P<0 .0 1;白细胞吞噬率为 (30 .5 6± 3.13) %vs.(2 2 .33± 3.71) % ,P <0 .0 1;白细胞趋化指数为 1.92± 0 .35vs.1.6 1± 0 .16 ,P <0 .0 1;CD4 /CD8比值为 :1.4 2± 0 .10vs.1.0 2± 0 .12 ,P <0 .0 1;血浆IgG含量为 8.10± 1.2 2 )g/Lvs.(5 .5 1± 1.6 2 )g/L ,P <0 .0 1;IgM为 (1.2 2± 0 .2 2 )g/Lvs.(0 .6 1± 0 .15 )g/L ,P <0 .0 1;动物病死率也明显降低 ,为 10 .0 0 %vs.35 .71% ,P <0 .0 1。　结论 :严重烧伤家兔机体免疫功能下降 ,经肠道补充精氨酸能有效提高烧伤后免疫功能 ,降低动物死亡率     

甘氨酸对热暴露大鼠的保护作用研究

目的观察抗内毒素药物甘氨酸在中暑内毒素血症发病过程中所起到的作用.方法将24只受试大鼠随机分为3组,每组8只,两个热暴露组分别于受热前给予甘氨酸(G)和生理盐水(NS),常温对照组(NC)暴露于室温.结果(1)热休克发生时间G组88.3±3.5min,NS组79.5±4.2min;存活时间(热休克发生至死亡时间)G组35.5±4.4min,NS组为18.0±4.5min.组间比较有显著差异(P＜0.01).(2)动物受试80min后肛温、心率,平均动脉压分别为G组42.5±0.4℃、459±9.9beats/min、11.5±0.8kPa;NS组43.1±0.4℃、483.3±9.4beats/min、9.3±0.8kPa;NC组37.1±0.3℃、360.8±10.6beats/nin、13.5±1.3kPa.不同组别对比差异显著(P＜0.05).结论G在抗动物热暴露所致的内毒素血症中起到了相当明显的作用.     

急性CO中毒后迟发性脑病患者脑脊液和血清可溶性白细胞介素-2受体水平

目的　探讨急性一氧化碳中毒后迟发性脑病 (DEACMP)患者血清和脑脊液可溶性白细胞介素 2受体 (sIL 2R)的变化。方法　采用双抗体夹心ELISA法测定 31例DEACMP患者入院时、出院前的sIL 2R含量 ,并与 32例其他脑病组和 31例对照组作比较。结果　DEACMP组血清sIL 2R水平[(32 9.2 1± 16 0 .99)U/ml]明显高于对照组 [(115 .6 7± 89.5 8)U/ml],差异有显著性 (P <0 .0 5 ) ;与其他脑病组 [(36 7.5 0± 12 3.14 )U/ml]比较 ,差异无显著性 (P >0 .0 5 ) ;DEACMP组脑脊液sIL 2R水平[(5 4 .4 8± 4 3.0 4 )U/ml]略高于对照组 [(34.96± 2 2 .70 )U/ml],但明显低于其他脑病组 [(110 .2 4±76 .5 6 )U/ml],差异有显著性 (P <0 .0 5 )。DEACMP组血清sIL 2R水平入院时 [(338.34± 16 1.5 3)U/ml]与出院前 [(35 1.31± 175 .93)U/ml]比较 ,差异无显著性 (P >0 .0 5 ) ,而脑脊液sIL 2R水平出院前[(10 0 .2 6± 93.6 5 )U/ml]较入院时 [(5 2 .2 8± 4 3.31)U/ml]明显增高 ,差异有显著性 (P <0 .0 5 )。结论　本病的发生与免疫病理损伤有关 ,血清和脑脊液sIL 2R水平可以反映DEACMP患者机体的免疫状态 ,对判断病情程度及预后有一定的价值。     

减压病小鼠血小板膜糖蛋白的表达

目的　探讨血小板膜糖蛋白CD31、CD61和CD62p表达在减压病发病机制中的作用。方法　 1 4只雌性昆明种小鼠随机分为减压病组和正常对照组。减压病组经 60 0kPa压缩空气暴露后 ,用 1min快速减压至常压。在减压后 60min时 ,用流式细胞术检测小鼠血小板膜糖蛋白CD31、CD61和CD62p表达。结果　减压病组小鼠血小板膜糖蛋白CD31的平均荧光强度 (1 8.64± 1 .0 1 )高于正常对照组 (1 6 .89± 1 .69) ,差异有显著性 (P <0 .0 5) ;减压病组小鼠血小板膜糖蛋白CD61的平均荧光强度 (2 71 .0 6± 2 4 .2 5)和CD62p的阳性百分数 (4.48%± 0 .43 % )均高于正常对照组 (分别为 2 34 .0 9± 1 5 .96、3 .0 0 %± 0 .66 % ) ,差异有非常显著性 (P <0 .0 1 )。结论　不适宜的快速减压可增强血小板膜糖蛋白CD31、CD61和CD62p的表达 ,促使血栓形成     

苦瓜皂甙对老年荷瘤小鼠免疫功能的影响

目的 :探讨苦瓜皂甙对老年荷瘤小鼠免疫功能的调节作用。方法 :15月龄雌性昆明小鼠 ,随机分为老年对照组、实验对照组、实验 1组和实验 2组。均喂以普通饲料 ,其中两对照组饮用自来水 ,两个实验组饮用分别为 10 0mg·L- 1和 2 0 0mg·L- 1苦瓜皂甙水。饲养 5周后 ,对后三组动物腹腔均接种 0 .1ml浓度为 10 6 ·ml 1的S180肿瘤细胞 ,1周后处死动物取标本待测。结果 :两个使用苦瓜皂甙组小鼠胸腺和脾脏组织中CD8+T细胞数有增高趋势 ,胸腺中CD4 +CD8+双阳性T细胞数显著降低〔老年对照组 :(6 8.0 9± 5 .2 6 ) % ,实验对照组 :(5 8.82± 6 .5 2 ) % ,实验 1组 :(5 0 .5 8± 3.74 ) % ,实验 2组 :(45 .85± 5 .75 ) %〕 ;血清IL - 2水平回升明显 ,血清TNFα含量显著增高 ;老年对照组、实验对照组、实验 1组和实验 2组 ,血清IL - 2分别为 (2 8.5 7± 4 .90 )、(17.14± 3.2 7)、(2 2 .86± 3.2 7)、(2 7.76± 4 .2 0 )ng·L- 1,血清TNFα分别为 (185 .5 3± 35 .34)、(2 4 5 .83±2 7.39)、(2 92 .2 1± 2 4 .74 )、(2 89.12± 2 5 .18)ng·L- 1。但是两个使用苦瓜皂甙组之间 ,所有指标均没有统计学差异。结论 :苦瓜皂甙可改善老年荷瘤小鼠免疫功能 ,增强机体抗肿瘤能力     

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 occurrence of antimicrobial substances in toilet,sink and shower drainpipes of clinical units: A neglected source of antibiotic residues

Antibiotics represent one of the most important drug groups used in the management of bacterial infections in humans and animals. Due to the increasing problem of antibiotic resistance, assurance of the antibacterial effectiveness of these substances has moved into the focus of public health. The reduction in antibiotic residues in wastewater and the environment may play a decisive role in the development of increasing rates of antibiotic resistance. The present study examines the wastewater of 31 patient rooms of various German clinics for possible residues of antibiotics, as well as the wastewater of five private households as a reference.To the best of our knowledge, this study shows for the first time that in hospitals with high antibiotic consumption rates, residues of these drugs can be regularly detected in toilets, sink siphons and shower drains at concentrations ranging from 0.02?μg·L^?1 to a maximum of 79?mg·L^?1. After complete flushing of the wastewater siphons, antibiotics are no longer detectable, but after temporal stagnation, the concentration of the active substances in the water phases of respective siphons increases again, suggesting that antibiotics persist through the washing process in biofilms. This study demonstrates that clinical wastewater systems offer further possibilities for the optimization of antibiotic resistance surveillance.     

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.