Variation de la plombemie en fonction de la contamination par le plomb de l'eau livree a la consommation: Variation of the blood lead level as a result of lead contamination of the subjects drinking water

The combination of the chemical aggressivity of water and lead piping, as is well known, can cause severe cases of lead poisoning in those who consume such water. After a great number of observations and epidemiological studies which have strongly incriminated this metal in a wide range of pathologic conditions, other materials have been gradually substituted for lead; however, the problem remains.In compliance with a European Directive to survey the risk of lead poisoning (Council Directive, 1977), a random sample of 321 residents was selected from the Vosgian Mountains of France. This region is noted for its high incidence of cases of lead poisoning: 150 reported during 8 months in 1983 (Barbier et al., 1983).During the course of a health evaluation, a blood sample was taken from each subject for lead analysis. At the same time, a sample of tap-water (after running for 5 s) was taken from each subject home. Both lead analyses (blood and water) were performed by electrothermal atomization-atomic absorption spectrophotometry. Because of the log-normality of the distributions of the blood lead levels and the concentrations of lead in the drinking water, a logarithmic transformation was performed so that the results are expressed as the geometric mean, which for the amount of lead in the drinking water of our sample was found to be 0.16 mg l^?1.Among the subjects of this study, 28% are served by water containing more than 0.10 mg l^?1 of lead (the standard for France) and 48% by water containing more than 0.05 mg l^?1 (the European and WHO standard). In concurrence with numerous authors, our study indicates that, among our subjects, the blood lead level is much higher in men than in women (geometric means 22.9 and 15.0 μg dl^?1 respectively); this difference is highly significant (t-test:P < 0.001). Table 1 summarizes the results, by sex, obtained in this region compared with those from a study (Huel, 1982) concerning an urban French population whose geometric mean blood lead levels were 15.9 μg dl^?1 for men and 11.4 μg dl^?1 for women. The irrespective of sex, is highly significant (P < 0.001). Table 2 shows the significance of the relation between these subjects, high blood lead levels and the concentration of lead in their drinking water, while Fig. 1 shows that for contamination levels up to 0.02 mg l^?1 of lead in water, the blood lead level remains relatively stable, while above this apparent “threshold” value, the blood lead level begins to increase finally reaching quite high values in response to high contamination levels, suggesting a direct translation of increases in the water above the 0.02 mg l^?1 level to increases in the blood.     

“菜鸟“小议

近年来,"菜鸟"作为一个新兴词语在网络上广为流传,甚至波及到社会生活的方方面面.通过语素分析和近义比较,可以来考察此词的读音和意义.     

基于PSR模型的水电工程生态效应评价指标体系构想

从水电工程生态效应评价指标体系研究的意义出发,通过分析水电工程生态效应评价的内涵,确立了评价指标的选取原则,基于压力(Pressure)-状态(State)-响应(Response)概念模型,构建了以科学、实用和可操作为目标的评价指标体系的框架。     

Effect of oxygen vacancies on transformation of zirconia at low temperatures

The effect of oxygen vacancy on the stability of phase structures and phase transformation of zirconia at low temperatures was studied using an electrochemical technique. It is suggested that the decrease of oxygen vacancies decreases the stability of metastable tetragonal zirconia and promotes its transformation to the monoclinic phase. This revised version was published online in November 2006 with corrections to the Cover Date.     

β″－Al_2O_3陶瓷的强化和韧化

研究了稳定ＺｒＯ＿２和部份稳定ＺｒＯ＿２对β″－Ａｌ＿２Ｏ＿３陶瓷的强化和韧化作用，观察了不同种类、不同含量的ＺｒＯ＿２对β″－Ａｌ＿２Ｏ＿３陶瓷的显微结构、力学性能和电导率的影响，探讨了β″－Ａｌ＿２Ｏ＿３的韧化机理。     

电子束、离子束与蓝宝石相互作用的研究

研究了电子束、离子束作用于Al2O3表面时成分的变化，表明无论电子束或离子束都能使Al2O3发生分解，产生导电的元素Al。实验在PHI610·SAM上进行，电子束轰击下（3keV，O．5μA，入射角60°）10s就有元素Al分解出来，2min以后就达到饱和，分解析出量随时间成a（1－e－bt）的关系。离子束轰击下同样发生元素Al的分解，但当Ei＞3keV时，由于剥离速率加大，溅射5min时表面Al峰反而比1min时要弱。这时表面Al含量处于分解析出与溅射剥离的动态平衡中。实验还发现了Al2O3的解析与表面成分有关（如碳的含量）。最后讨论电子束与离子束的解析机理。     

Apoptosis in the early stage of compensatory renal growth following uninephrectomy in the young and old rats

Myostatin (GDF-8) is a member of the transforming growth factor-beta superfamily and plays a role in muscle growth and development. Mice having targeted disruption of this gene display marked increases in muscle mass, a phenotype similar to the muscular hypertrophy (mh) in several cattle breeds. Physical mapping data developed from YAC clones indicate the bovine myostatin gene lies close to the centromere of bovine Chromosome (Chr) 2 (BTA2) at 2q11, indistinguishable from the cytogenetic location of the mh locus. In addition, a polymorphism in the second intron of the gene was used to show that myostatin maps within the interval previously shown to contain mh. These data suggest myostatin may be the gene causing muscular hypertrophy in cattle.     

基于Native Mode ATM API的应用系统模型及关键技术

ＡＴＭ技术作为Ｂ－ＩＳＤ的基础，在传输包括话音、图像、数据的综合业务环境中具有现有其它网络技术所不具备的技术优势，然而目前真正基于ＡＴＭＮａｔｉｖｅＭｏｄｅ的应用还很少，而大量基于Ｏｖｅｒｌａｙ Ｍｏｄｅ的ＡＴＭ应用不能充分发挥ＡＴＭ技术的优势。随着信息技术的发展，将会有大量的综合业务应用出现，它具有和传统数据通信安全不同的业务特性，必须通过一种灵活，高效的应用程序接口给予支持，本文提出基于Ｎａｔ     

替代进口梳棉机测厚传感器集成电路芯片分立元件的电路设计

介绍了替代进口梳棉机测厚传感器集成电路分立元件的电路图，工作原理及特点。一年多的实际运行证明，电路参数达到了设计要求。     

络合沉淀法制备BaTiO_3超细粉末

在分析ＢａＴｉＯ_３前驱体形成机理的基础上，提出了以草酸作为络合剂，用络合沉淀法制备超细ＢａＴｉＯ_３新工艺。用化学分析法测定产物Ｂａ／Ｔｉ比，用ＸＲＤ、ＴＥＭ、ＢＩ－９０激光散射粒度仪对产物的晶型、粒度及形貌进行表征。结果表明：采用该法合成的前驱体，微观组分确定，粒径小，粒度分布窄，近似球形，煅烧后为高纯超细ＢａＴｉＯ_３粉末。