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室内PM_(10)对DNA氧化性损伤及其与微量元素组成关系 被引量:9
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作者 邵龙义 赵厚银 +2 位作者 T.P.Jones 吕森林 L.Merolla 《自然科学进展》 北大核心 2005年第4期417-422,共6页
使用质粒DNA评价法(plasmid DNA assay)和电感偶合等离子体质谱(ICP-MS)研究了北 京市室内外PM10(可吸入颗粒物)的生物活性及与微量元素的关系.选择了4组样品分别代表吸烟 室内(1),非吸烟室内(2)和相应室外(1)进行质粒DNA评价研究.结果... 使用质粒DNA评价法(plasmid DNA assay)和电感偶合等离子体质谱(ICP-MS)研究了北 京市室内外PM10(可吸入颗粒物)的生物活性及与微量元素的关系.选择了4组样品分别代表吸烟 室内(1),非吸烟室内(2)和相应室外(1)进行质粒DNA评价研究.结果表明,室内PM10对超螺旋 DNA的氧化性损伤高于室外;吸烟室内PM10的TD50(引起50%DNA损伤所需的颗粒物剂量)低 达100 μg·mL-1,对DNA氧化性损伤最大,说明吸烟室内PM10的生物活性最大.结合微量元素 分析发现,吸烟室内PM10的水溶性Zn与TD50负相关性较其他元素强,说明水溶性Zn可能对 DNA的氧化性损伤起重要作用.Fe元素虽然被认为是最具生物活性的元素之一,但是在所分析样 品中Fe元素多是以不可溶状态存在,因此对DNA损伤较弱. 展开更多
关键词 氧化性损伤 PM10 组成关系 质粒DNA DNA损伤 生物活性 可吸入颗粒物 等离子体质谱 超螺旋DNA 微量元素分析 电感偶合 负相关性 分析样品 水溶性 吸烟 评价法 室内外 北京市 室外 Zn Fe 起重
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Quaternary: status, rank, definition, survival 被引量:3
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作者 Marie-PierreAubry WilliamA.Berggren +3 位作者 JohnVanCouvering BrianMcGowran BradPillans FritsHilgen 《Episodes》 SCIE 2005年第2期118-120,共3页
The long controversy over the term ‘Quaternary' as a chronostratigraphic unit may be reaching an apotheosis, judging from recent papers (Pillans and Naish, 2004; Gibbard et al., 2005; and referencest herein). The... The long controversy over the term ‘Quaternary' as a chronostratigraphic unit may be reaching an apotheosis, judging from recent papers (Pillans and Naish, 2004; Gibbard et al., 2005; and referencest herein). The debate is no longer centered on whether there should be a place in the geological time scale for a unit termed ‘Quaternary'-despite its dubious past, it cannot be denied that a large body of earth-historical research is strongly identified with this term. The challenge now concerns an appropriate rank and definition of Quaternary with regard to other chronostratigraphic units. Several options have been proposed (Pillans and Naish, 2004), and Gibbard et al. (2005) encourage a debate on these before decision is reached. In this brief note, we describe an arrangement not previously considered that seems advantageous. It is instructive, however, to first review the Pleistocene Series and Neogene System, the two units that are directly affected by introduction of the Quaternary into the chronostratigraphic hierarchy. 展开更多
关键词 第四纪冰川 地形特征 沉积作用 识别方法
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A geological survey in transition
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作者 PeterM.Allen BernardELeake 《Episodes》 SCIE 2004年第3期223-224,共2页
This is an account of the changes in funding, administration, and management of the British Geological Survey (BGS), the oldest government-funded geological survey in the world, from the early 1980s to 2000. It will i... This is an account of the changes in funding, administration, and management of the British Geological Survey (BGS), the oldest government-funded geological survey in the world, from the early 1980s to 2000. It will interest students of public administration, historians of science and geological surveys, and those who have followed the convoluted recent history of BGS. Peter Allen has rendered a most valuable service in documenting and describing as an insider (he only recently retired from a position as Assistant Director) the struggles to maintain the Survey and its prime role of discovering, 展开更多
关键词 地质勘测 资源浪费 效益评估 地图测绘
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