转基因蓝藻地不同龄期淡色库蚊幼虫杀灭作用的实验研究

目的：观察３各基因工程杀蚊幼蓝藻对不同龄期淡色库蚊幼虫的杀灭效果。方法：利用不同基因工程藻，分别作用于不同龄期淡色库蚊幼虫，计算死亡率，结果：３种基因工程藻对不同龄期淡以库蚊幼虫杀灭作用相似；在藻细胞浓度低于１０＾４ｃｅｌｌｓ／ｍｌ时，杀灭作用由强到弱依次为Ｉ龄、Ⅱ龄、Ⅲ龄末Ⅳ龄初幼虫；而当藻细胞浓度高于１０＾５ｃｅｌｌｓ／ｍｌ时，对该蚊不同龄期幼虫的杀灭作用均高效。结论：应用基因工程藻现场控制蚊     

转基因蓝藻对不同龄期淡色库蚊幼虫杀灭作用的实验研究

目的：观察３种基因工程杀蚊幼蓝藻对不同龄期淡色库蚊幼虫的杀灭效果。方法：利用不同浓度基因工程藻，分别作用于不同龄期淡色库蚊幼虫，计算死亡率。结果：３种基因工程藻对不同龄期淡色库蚊幼虫杀灭作用相似；在藻细胞浓度低于１０４ｃｅｌｓ／ｍｌ时，杀灭作用由强到弱依次为Ⅰ龄、Ⅱ龄、Ⅲ龄末Ⅳ龄初幼虫；而当藻细胞浓度高于１０５ｃｅｌｓ／ｍｌ时，对该蚊不同龄期幼虫的杀灭作用均高效。结论：应用基因工程藻现场控制蚊幼虫宜尽早喷施，可提高杀灭效果。     

3种杀蚊幼剂防治白纹伊蚊幼虫的效果观察

目的观察3种杀蚊幼剂现场杀灭白纹伊蚊幼虫的效果,为防控登革热媒介伊蚊提供技术支持。方法1%双硫磷颗粒缓释剂、600 ITU/mg苏云金杆菌悬浮剂、100 ITU/mg球形芽孢杆菌悬浮剂按使用说明剂量施于白纹伊蚊幼虫孳生的中小型水体中。结果双硫磷颗粒缓释剂、苏云金杆菌生物悬浮剂、球形芽孢杆菌悬浮剂施药后1～3 d对白纹伊蚊幼虫防治效果达100%,大于80%持效期分别为60、30、20 d。结论 3种杀蚊幼剂均可有效控制白纹伊蚊幼虫孳生。     

基因工程杀蚊幼蓝藻的研究

应用基因工程手段研制杀蚊幼蓝藻,是解决苏云金杆菌和球形芽孢杆菌等短持效问题的途径之一。但国际上基因工程蓝藻的毒效一直限于较低水平,甚至需要破碎细胞才能检测到对蚊幼虫的毒杀作用。本文将球形芽孢杆菌毒素基因装配鱼腥藻启动子后,转移入鱼腥藻进行表达,所得基因工程株对蚊幼虫具有十分显著的毒效,对淡色库蚊幼虫24h半致死浓度为2.31×10~4细胞/ml;其对淡色库蚊、中华按蚊、白纹伊蚊幼虫的毒效依次递减,这与球形芽孢杆菌相似。由于鱼腥藻易培养、生态适应性广等,可望成为蚊虫特效控制的新型武器。     

基因工程杀蚊幼蓝藻稳定性的实验研究

目的：探讨基因工程藻高效杀蚊幼活性，以确定其质粒表达情况。方法：抗性筛选及蚊虫毒效测试。结果：随机筛选出的基因工程单藻落无一抗性丢失，且３种基因工程藻对淡色库蚊仍具较高毒效，ＬＣ５０（２４小时）Ａ．７１２０ｐＤＣ２６为８．２６×１０３ｃｅｌｓ／ｍｌ；Ａ．ｓｕｂｔｒｏｐｉｃｐＤＣ２６为２．６２×１０４ｃｅｌｓ／ｍｌ；Ａ．ｃｙｌｉｎｄｒｉｃａｔｏｘ为４．２１×１０３ｃｅｌｓ／ｍｌ。结论：穿梭质粒在基因工程藻细胞内稳定遗传，并持续高效表达。     

球形芽孢杆菌C_（3－41）地方株制剂控制城市致乏库蚊的现场效果评价

笔者从１９９３年５月始在武汉市水果湖地区应用球形芽孢杆菌Ｃ（３－４１）地方株制剂，进行大面积控制致乏库蚊的现场研究。结果表明，用３ｍｌ／ｍ２球形芽孢杆菌Ｃ（３－４１）乳剂，对大型致乏库蚊孳生地每１０天处理１次，包括水塘、水沟、水槽及水坑；另用３ｇ／ｍ２块剂每月处理１次水缸和小容器等，可使幼虫密度下降３８～９９％，并能有效地控制成蚊密度和削平致乏库蚊成蚊的季节高峰。     

干燥贮存的基因工程藻杀灭淡色库蚊幼虫的实验研究

目的 :观察干燥贮存的基因工程藻对淡色库蚊幼虫的杀灭效果。方法 :干燥、贮存和毒性测试。结果 :3种转基因工程藻经干燥贮存后仍具有较高杀蚊毒效 ;但随着贮存时间的延长 ,其杀灭作用有所下降。 3种转基因工程藻之间杀蚊幼效果无明显差异。结论 :蓝藻质粒在干燥贮存的工程藻内仍能稳定遗传 ,因而利于现场推广应用     

苏云金杆菌悬浮剂杀灭白纹伊蚊不同龄期幼虫实验及其影响因素分析

目的：研究苏云金杆菌悬浮剂对不同龄期白纹伊蚊幼虫杀灭效果及其影响因素分析；方法：实验室，现场实验；结果：苏云金杆菌悬浮剂对白纹伊蚊I—Ⅳ龄初幼虫能得到100％的杀灭效果，对蛹和即将化蛹的Ⅳ龄末幼虫完全无杀灭效果，积水中的沉积物可影响苏云金杆菌悬浮剂对白纹伊蚊幼虫的杀灭效果，沉积物越多(1／2—2／3)，幼虫的杀灭率就越低，最高为66％，苏云金杆菌悬浮剂对南方地区白纹伊蚊阳性小容器积水幼虫有良好的控制效果，持效可达10d；结论：苏云金杆菌悬浮剂对白纹伊蚊幼虫有良好的杀灭效果，沉积物较多的积水则用高剂量药，为提高持效，用药后7d要重施药。     

大肠埃希菌表达苏云金杆菌cryIVD基因杀蚊幼活性观察

目的 :观察表达B .t.icryIVD基因的大肠埃希菌对蚊幼虫的毒效。 方法 :细菌的诱导表达及蚊虫毒效测试。结果 :加入工程菌 48h对淡色库蚊和白纹伊蚊均具有明显的杀灭作用 ,LC50 分别为 2 .3 8× 10 6 、1.6× 10 7个 ml细胞 ,其中对淡色库蚊的杀灭作用要好于对白纹伊蚊幼虫的杀灭效果。结论 :单独表达B .t .icryIVD基因具有杀蚊作用     

苏云金杆菌CryIVD转基因工程藻不同贮存时间对淡色库蚊不同龄期幼虫的杀灭效果

目的观察苏云金杆菌CryIVD转基因贮存藻对不同龄期淡色库蚊幼虫的杀灭效果。方法大量培养工程藻,干燥后保存,应用不同时间的贮存藻作用于不同龄期淡色库蚊幼虫。结果干燥贮存的工程藻数年后仍有较高的杀蚊毒效,尽管杀蚊毒效较新鲜工程藻有所下降,但在105个/ml数量级不同龄期的幼虫仍有50%以上死亡。对不同龄期淡色库蚊幼虫杀灭效果比较表明,1~3年贮存藻3组比较,在106个/ml数量级浓度的蚊幼虫死亡率差异无统计学意义（F=9.32,P〉0.01）,而贮存1年组和3年组在105个/ml数量级浓度及以下,死亡率差异有统计学意义（F=101.21,P〈0.01）。结论转基因蓝藻在干燥贮存情况下仍能保持毒蛋白的稳定遗传和杀幼虫作用,为今后的现场应用提供更方便的选择。     

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.     

The risk of heat exhaustion at a deep underground metalliferous mine in relation to surface temperatures

The risk of heat exhaustion at a deep underground metalliferous mine was assessed in relation to thermal conditions prevailing on the surface. For each day of a 1-year prospective case series of heat exhaustion, surface 24-h mean wet and dry bulb temperatures were recorded. From this data, 24-h mean wet bulb globe temperatures were derived using certain assumptions. The three surface temperature variables were significantly higher on those days on which heat exhaustion occurred, compared to those days on which it did not occur (P < 0.001). The relative risk of heat exhaustion on days when the 24-h mean wet bulb globe temperature was in the range 26.0-28.0 degrees C was 4.82 (95% confidence interval 2.12-10.96). Surface temperature data could be used at this mine to warn miners about the risk of heat exhaustion.