Problems in prenatal diagnosis of β-thalassaemia by fetal blood analysis: β-chain variant comigrating with gamma chains

This report describes a couple at risk for β thalassaemia in which one spouse was heterozygous for classical high Hb A2 β-thalassaemia while the other had the compound heterozygous state for β⁺-thalassaemia and a β-chain variant. This variant comigrates on carboxymethyl-cellulose columns (CMC) with γ-chains, indicating that globin separation on CMC columns could not have been used for fetal diagnosis. The β-chain variant migrates separately from the other globin chains on HPLC and the respective abnormal haemoglobin can be separated by isoelectrofocusing. Oligonucleotide hybridization showed that both parents were carriers of the β⁺ IVS-1, nt 6 mutation. Prenatal diagnosis was successfully accomplished by oligo-nucleotide analysis on trophoblast DNA. This case indicates that an Antenatal Service should have alternative methods to CMC columns so as to carry out prenatal diagnosis of β-thalassaemia in uncommon cases.     

TiO2/beads as a photocatalyst for the degradation of X3B azo dye

The feasibility of photocatalytic degradation of X3B azo dye by TiO2/beads photocatalyst was studied.The effects of parameters such as the amount of TiO2/beads,airflow ,as well as the concentrations of H2O2,Fe^3 ,Mg^2 and Na^ on the photocatalytic degradation of X3B azo dye were also studied.The results showed that 25mg/dm^3 X3B azo dye can be photocatalytically degraded completely by 30 min illumination with a 375W medium pressure mercury lamp.Adding a small amount of H2O2 or Fe^3 ,the efficiencies of photocatalytic degradation of X3B azo dye were increased rapidly.The mechanisms of the reaction and the role of the additives were also investigated.After 120 hours TiO2/beads showed no significant loss of the photocatalytic activity.     

First trimester diagnosis of β-thalassaemia in a twin pregnancy

This paper reports the results of first trimester prenatal diagnosis in a twin pregnancy at risk for homozygous β°−thalassaemia (β°−39 mutant). Trophoblast samples from both twins were obtained at 10 weeks gestation with a forceps guided by ultrasound. Trophoblast DNA analysis, carried out with the oligonucleotide technique, revealed that one fetus was homozygous and the other heterozygous for the β−39 mutant. This diagnosis was confirmed at 17 weeks gestation by amniocyte DNA analysis. DNA polymorphism analysis within the α-globin gene provided useful genetic markers for twin differentiation.     

浅谈火电厂烟气连续监测系统（CEM）

近几年，随着我国环境保护意识的不断提高，环境保护工作也日益加强，为了做到环境和经济持续协调发展，必须要求建设项目加强污染防治对策，加强环保管理部门的有效监督。火电厂装设烟气连续监测系统（CEM）就是对其大气污染物的排放进行连续监测，为生产运行和环保管理部门提供基础数据，本文介绍了电厂CEM系统的分析系统。     

人工快速渗滤系统处理糖蜜酒精废水的研究

本实验研究应用人工快速渗滤系统处理糖蜜酒精废水,实验结果表明,当湿干比为1∶1,配水时间4 h,处理效果最佳,负荷可达到2.13～2.94 m3/(m2·d).在进水CODCr浓度＜800 mg/L时,CODCr的去除率达到80%以上,但随着进水CODCr浓度的升高,CODCr的去除率缓慢下降,当CODCr浓度超出2 500 mg/L时,系统的生物膜降解不再发生作用,只存在简单的机械过滤作用.     

膨胀石墨吸附材料在环境保护中的应用

介绍了膨胀石墨吸附材料的特点、结合国内外研究资料和我们对膨胀石墨吸附性能的研究，重点分析了这种新型吸附材料在环境保护中的各种用途     

用增量网格法对空心复合挤压的实验研究

用增量网格法对带内孔坯复合挤压的载荷、上下通道流出量、金属内部应力应变分布情况进行实验分析,并分析内孔直径和凹模锥角等参数的影响,对设计模具与选择成形设备有指导意义.文中还阐述这种实验方法的实施过程和功能,指出这是一种研究成形问题的有效手段.     

环境空气影响评价保证率法浓度预测技术

通过小时、日均污染物浓度预测多种现行方法的分析比较,对保证率法进行了技术改进,100%保证率法才能够满足当前环境空气质量标准和环评导则的相关要求。在此基础上开发“环境空气影响评价保证率法浓度预测系统”,建立了一套准确、系统的实用技术方案。     

Chorionic villus sampling and acceptance rate of prenatal diagnosis

In this paper, we compared the acceptance rate of fetal diagnosis for β-thalassemia in three group of couples of Sardinian descent; the first counselled before DNA analysis was available, the second presenting after DNA analysis was introduced but too late for chorionic villus sampling and thus monitored by amniocyte DNA analysis and the third presenting within the first trimester after DNA analysis was introduced and thus in time for trophoblast DNA analysis. A higher proportion of couples from the latter group opted for fetal testing as compared to the 1st and 2nd group. These results indicate that in this population, introduction of 1st trimester diagnosis made prenatal testing acceptable to practically all counselled couples at risk.     

珠江三角洲一些城市水体中微量有机污染物的初步研究

对珠江三角洲流经城市的７条河流和３条干流水道（东、西、北江）以及广州，深圳、肇庆的城市污水中的半挥发性微量有机污染物进行了分析，并对其污染状况以及污染来源进行了初步评价。研究表明，珠江三角洲内流经城市的７条河流受到的有机物污染比３条干流水道严重得多。氯代芳烃，正烷烃，酞酸酯和多环芳烃是珠江三角洲水体中最普遍存在的微量有机物污染物，其中属于ＥＰＡ优先控制的污染物有１２种。“ＥＰＡ协议法令”规定的污染