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1.
Three monoclonal antibodies (MAbs) against trophoblast (GB17, GB21, and GB25) and flow cytometry were used to sort trophoblast-like cells (TLCs) from peripheral blood of pregnant women. Sorted TLCs were processed for electron microscopy and fetal DNA amplification of the Y-specific sequences from mothers carrying male fetuses. At the ultra-structural level, most of the nucleated cells had the morphology of leucocytes, suggesting maternal contaminants, and we did not find the characteristic features of the free inter-villous trophoblast cells. Nevertheless, polymerase chain reaction (PCR) analysis showed an amplification of Y-specific sequences in two out of three samples of sorted TLCs. These results suggest that besides the maternal leucocytes, sufficient trophoblast nucleated fetal cells can be obtained using cell enrichment by sorting. This sensitive method holds promise for non-invasive prenatal diagnosis of fetal sex and if sufficient Y(positive) nuclei are found, for the diagnosis of selected numerical chromosome abnormalities.  相似文献   
2.
Few studies have been carried out to connect nutrient recovery as struvite from wastewater and sustainable utilization of the recovered struvite for copper and zinc immobilization in contaminated soil. This study revealed the effect of struvite on Cu and Zn immobilization in contaminated bio-retention soil in the presence of commonly exuded plant organic acids. The research hypothesis was that the presence of both struvite and organic acids may influence the immobilization of Cu and Zn in soil. The outcome of this research confirmed that more than 99% of Cu and Zn was immobilized in bio-retention filter media by struvite application. Water-soluble Cu and Zn concentrations of struvite treated soil were less than 1.83 and 0.86 mg/kg respectively, and these concentrations were significantly lower compared to the total Cu and Zn content of 747.05 mg/kg in the contaminated soil. Application of struvite to Cu- and Zn-contaminated soil resulted in formation of compounds similar to zinc phosphate tetrahydrate (Zn3(PO4)2?4H2O) and amorphous Cu and Zn phases. Struvite was effective in heavy metal remediation in acidic soil regardless of the presence of Ca impurities in struvite and the presence of plant organic acids in soil. Overall, this study revealed that struvite recovered from wastewater treatment plants has potential for use as an amendment for heavy metal remediation in contaminated bio-retention soil.  相似文献   
3.
为揭示升流式厌氧污泥床(UASB)反应器启动运行效能与互营丙酸降解菌群数量之间的关系,以稀释的玉米淀粉生产废水为底物,考察了UASB启动期的运行特征,并采用实时荧光定量PCR技术(qPCR)分析了互营丙酸降解菌群(丙酸氧化菌和产甲烷菌)的演替规律.结果表明,在进水COD 2000mg/L和水力停留时间(HRT)24h条件下,经过38d的连续运行,COD去除率达到了91.9%.当HRT分阶段缩短至8h时,比产甲烷速率达到了315LCH4/(kg COD·d),且形成了沉降性能良好的颗粒污泥.qPCR检测结果表明,至少有5种已鉴定的丙酸氧化菌存在于UASB反应器中.Pelotomaculum propionicum为接种污泥中的主要丙酸氧化菌,约占检测到丙酸氧化菌总数的45.7%.它的数量随着HRT缩短不断减少.而Syntrophobacter sulfatireducens和S.wolinii的数量随着HRT缩短不断增加,并在启动完成时达到最大值,分别为1.3×103,5.5×103个16S rRNA基因拷贝数/ng DNA,演替成为成熟颗粒污泥中的优势丙酸氧化菌群.Methanobacterium和Methanosarcina为接种污泥中的主要氢营养型产甲烷菌和乙酸营养型产甲烷菌,其数量随着HRT的缩短而逐渐减少,而Methanospirillum和Methanosaeta的数量随HRT的缩短逐渐增加,成为成熟颗粒污泥中的优势产甲烷菌群.  相似文献   
4.
Wastewater treatment center(WTC) workers may be vulnerable to diseases caused by viruses, such as the common cold, influenza and gastro-intestinal infections. Although there is a substantial body of literature characterizing the microbial community found in wastewater, only a few studies have characterized the viral component of WTC aerosols,despite the fact that most diseases affecting WTC workers are of viral origin and that some of these viruses are transmitted through the air. In this study, we evaluated in four WTCs the presence of 11 viral pathogens of particular concern in this milieu and used a metagenomic approach to characterize the total viral community in the air of one of those WTCs. The presence of viruses in aerosols in different locations of individual WTCs was evaluated and the results obtained with four commonly used air samplers were compared.We detected four of the eleven viruses tested, including human adenovirus(h Ad V),rotavirus, hepatitis A virus(HAV) and Herpes Simplex virus type 1(HSV1). The results of the metagenomic assay uncovered very few viral RNA sequences in WTC aerosols, however sequences from human DNA viruses were in much greater relative abundance.  相似文献   
5.
王刚  李东峰 《干旱环境监测》2003,17(3):180-183,F003
利用EXCEL强大的数据处理功能,可以方便地对精密度—偏性分析质控数据进行处理,具有较高的推广价值。  相似文献   
6.
乌鲁木齐市餐饮业油烟污染的调查及防治初探   总被引:1,自引:0,他引:1  
通过对乌鲁木齐市20家餐饮业油烟污染的调查分析,结果表明,乌鲁木齐市餐饮业油烟污染严重,并提出了防治措施。  相似文献   
7.
研究了乌鲁木剂铁路局系统污水治理污染控制方法及途径,提出了主要污染物为石油类,其最佳治理对策是:确定重点污染单位、污染源、用最低的治理投入,选择斜板隔油气浮工艺治理重点污染和次重点污染部门,得到较好的治理效果,否定盲目追求“零排放”的高投入方案。  相似文献   
8.
建立了过氧化聚吡咯(OPPy)和聚乙烯吡咯烷酮(PVP)修饰碳糊电极测定废水中苯酚的方法.优化了试验条件,苯酚的氧化峰电流在1.0×10-5 mol/L~1.0×10-3 mol/L之间线性关系良好,检出限为1.0×10-6 mol/L.该电极制作简单,选择性好,测定灵敏度高,精密度与准确度均符合要求.  相似文献   
9.
提高污水汽提装置液氨质量的研究   总被引:1,自引:0,他引:1  
介绍了含硫污水汽提装置为提高净化水合格率及液氨质量对工艺和设备采取的一系列改造措施  相似文献   
10.
Sulphate leaching losses may reduce the long-term possibility of maintaining the S supply of crops in low input farming systems. The ability of catch crops (Italian ryegrass (Lolium multiflorum Lam), winter rape (Brassica napus L.) and fodder radish (Raphanus sativus L.)) to reduce soil sulphate concentrations in autumn and make it available to a succeeding crop was investigated in 1996–1998 on sandy loam soil in Denmark. All catch crops reduced soil sulphate concentrations in the autumn compared to bare soil. Especially, the cruciferous catch crops had the ability to deplete efficiently soil sulphate levels and thus, reduce the sulphate leaching potential. The S uptake in aboveground catch crop was 8, 22 and 36 kg S per ha for ryegrass, winter rape and fodder radish, respectively. In the following spring, sulphate levels of the autumn bare soil were low in the top 0.5 m and a peak of sulphate was found at 0.75–1 m depth. In contrast, where a fodder radish catch crop had been grown, high sulphate levels were present in the top 0.5 m, but only small amounts of sulphate were found at 0.5–1.5 m depth. In spring barley (Hordeum vulgare L.), that followed catch crops, S concentrations at heading and maturity revealed that the availability of soil S increased following winter rape and fodder radish, whereas there were indications that following ryegrass, the S availability was reduced compared to bare soil. This initial study showed that catch crops have a high potential for reducing sulphate leaching and may be used to synchronise S availability with plant demand in a crop rotation.  相似文献   
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