背景与目的中国云南省宣威地区是世界非吸烟女性肺癌发病率最高的地区之一,其发病率是中国其他地方的20倍,前期研究认为,这种高肺癌发病率可能与当地出产和使用的烟煤燃烧产物中含有的二氧化硅颗粒物有关。本研究将从宣威地区出产的烟煤...背景与目的中国云南省宣威地区是世界非吸烟女性肺癌发病率最高的地区之一,其发病率是中国其他地方的20倍,前期研究认为,这种高肺癌发病率可能与当地出产和使用的烟煤燃烧产物中含有的二氧化硅颗粒物有关。本研究将从宣威地区出产的烟煤(C1烟煤)燃烧产物中分离二氧化硅颗粒物并进行表征,同时研究这种自然产出的二氧化硅颗粒物对正常人支气管上皮细胞(BEAS-2B)的体外毒性。方法①物理法从C1烟煤燃烧后的底灰中分离二氧化硅颗粒物,扫描电镜(scanning electron microscope,SEM)观察分离出的颗粒物形态,能谱分析显微组分的依存关系,透射电镜(transmission electron microscope,TEM)观察单颗粒形貌,激光粒度分析仪分析其颗粒物粒径分布,BET氮吸附比表面积仪测定颗粒物表面积;②应用3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)比色法检测分离出的二氧化硅处理组(实验组)、工业生产的纳米二氧化硅处理组和结晶型二氧化硅处理组(对照组)的细胞成活率变化,测定经刺激24h-72h后细胞内活性氧化酶(ROS)和乳酸脱氢酶(LDH)含量变化。结果①我们从C1烟煤燃烧后的底灰中分离出二氧化硅颗粒物,这些颗粒物粒径大小不一,30nm到120nm的颗粒物占86.8%,形态各异,表面不光滑,赋存有铝、钙和铁等元素;②相同浓度下,与工业生产的纳米二氧化硅和结晶型二氧化硅相比,自然产出的纳米二氧化硅对BEAS-2B有更高的体外毒性。结论①物理法能从C1烟煤底灰中分离出天然的纳米二氧化硅颗粒物,且不改变原有的形貌特征和显微组分的依存关系;②天然产出的纳米二氧化硅因形貌不规则、高比表面积和复杂的化学组分可能比工业生产的纳米二氧化硅和结晶型二氧化硅具有更高的细胞毒性。展开更多
The influence of human security components on Sexual Reproductive Health and Rights （SRHR） of individuals was explored in four sub-Saharan Africa countries of Angola, the Democratic Republic of Congo, Liberia and Ug...The influence of human security components on Sexual Reproductive Health and Rights （SRHR） of individuals was explored in four sub-Saharan Africa countries of Angola, the Democratic Republic of Congo, Liberia and Uganda from November 2008 to April 2009. The present results suggest that the major threat to human security is the competing economic demands that make it difficult for the population to prioritize reproductive health services in their household budgets. This study concludes that there are potential benefits of human security approaches for furthering the goals of SRHR initiatives, in line with the principles and guidelines expressed in the Maputo Plan of Action and the Millennium Development Goals （MDGs）. The results of this study suggest that IPPF Africa Region can start to prioritize economic security, community security and health security which have greatest impact on the reproductive health of the sub-Saharan African population. The key lesson learnt is that the effective use of family planning services mitigates the effects of other human insecurities, including economic, food, and health insecurities as its application in the families will reduce family size and demand on available resources.展开更多
悉尼皇家植物园(The Royal Botanic Garden,Sydney)创建于1816年,经过200年的发展,从最早的仅具植物收集、科研功能的机构逐渐演变成集公众休闲、娱乐,城市历史、文化、艺术展示为一体的综合性城市植物园。本文通过对悉尼皇家植物园历...悉尼皇家植物园(The Royal Botanic Garden,Sydney)创建于1816年,经过200年的发展,从最早的仅具植物收集、科研功能的机构逐渐演变成集公众休闲、娱乐,城市历史、文化、艺术展示为一体的综合性城市植物园。本文通过对悉尼皇家植物园历史资料收集和规划设计的研究,总结其发展历程并探讨其地域性特色。展开更多
文摘背景与目的中国云南省宣威地区是世界非吸烟女性肺癌发病率最高的地区之一,其发病率是中国其他地方的20倍,前期研究认为,这种高肺癌发病率可能与当地出产和使用的烟煤燃烧产物中含有的二氧化硅颗粒物有关。本研究将从宣威地区出产的烟煤(C1烟煤)燃烧产物中分离二氧化硅颗粒物并进行表征,同时研究这种自然产出的二氧化硅颗粒物对正常人支气管上皮细胞(BEAS-2B)的体外毒性。方法①物理法从C1烟煤燃烧后的底灰中分离二氧化硅颗粒物,扫描电镜(scanning electron microscope,SEM)观察分离出的颗粒物形态,能谱分析显微组分的依存关系,透射电镜(transmission electron microscope,TEM)观察单颗粒形貌,激光粒度分析仪分析其颗粒物粒径分布,BET氮吸附比表面积仪测定颗粒物表面积;②应用3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)比色法检测分离出的二氧化硅处理组(实验组)、工业生产的纳米二氧化硅处理组和结晶型二氧化硅处理组(对照组)的细胞成活率变化,测定经刺激24h-72h后细胞内活性氧化酶(ROS)和乳酸脱氢酶(LDH)含量变化。结果①我们从C1烟煤燃烧后的底灰中分离出二氧化硅颗粒物,这些颗粒物粒径大小不一,30nm到120nm的颗粒物占86.8%,形态各异,表面不光滑,赋存有铝、钙和铁等元素;②相同浓度下,与工业生产的纳米二氧化硅和结晶型二氧化硅相比,自然产出的纳米二氧化硅对BEAS-2B有更高的体外毒性。结论①物理法能从C1烟煤底灰中分离出天然的纳米二氧化硅颗粒物,且不改变原有的形貌特征和显微组分的依存关系;②天然产出的纳米二氧化硅因形貌不规则、高比表面积和复杂的化学组分可能比工业生产的纳米二氧化硅和结晶型二氧化硅具有更高的细胞毒性。
文摘The influence of human security components on Sexual Reproductive Health and Rights （SRHR） of individuals was explored in four sub-Saharan Africa countries of Angola, the Democratic Republic of Congo, Liberia and Uganda from November 2008 to April 2009. The present results suggest that the major threat to human security is the competing economic demands that make it difficult for the population to prioritize reproductive health services in their household budgets. This study concludes that there are potential benefits of human security approaches for furthering the goals of SRHR initiatives, in line with the principles and guidelines expressed in the Maputo Plan of Action and the Millennium Development Goals （MDGs）. The results of this study suggest that IPPF Africa Region can start to prioritize economic security, community security and health security which have greatest impact on the reproductive health of the sub-Saharan African population. The key lesson learnt is that the effective use of family planning services mitigates the effects of other human insecurities, including economic, food, and health insecurities as its application in the families will reduce family size and demand on available resources.
文摘悉尼皇家植物园(The Royal Botanic Garden,Sydney)创建于1816年,经过200年的发展,从最早的仅具植物收集、科研功能的机构逐渐演变成集公众休闲、娱乐,城市历史、文化、艺术展示为一体的综合性城市植物园。本文通过对悉尼皇家植物园历史资料收集和规划设计的研究,总结其发展历程并探讨其地域性特色。
