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361.
针对北方某采用升级A/O工艺的生活污水处理厂,使用实时荧光定量PCR技术,探究污水厂中ARGs的分布及各处理工艺段对ARGs的去除效果.结果表明:四环素抗性基因(tetA、tetC和tetM)、磺胺抗性基因(sul1和sul2)、大环内酯抗性基因(ermA和ermF)和喹诺酮抗性基因(parC和gyrA)在污水和污泥中均被检出.污水厂进水中ARGs的绝对丰度为2.65×103~1.01×106 copies·mL-1,升级A/O工艺未能有效削减ARGs,出水中ARGs的绝对丰度为9.22×103~1.15×106 copies·mL-1,污泥中ARGs的绝对丰度为8.07×107~2.65×1011 copies·g-1.深度处理工艺对ARGs的去除效率对比结果显示,生物活性炭工艺对ARGs的削减效果优于紫外消毒.  相似文献   
362.
To correctly assess and properly manage the public health risks associated with exposure to contaminated water,it is necessary to identify the source of fecal pollution in a watershed.In this study,we evaluated the efficacy of our two previously developed real time-quantitative PCR(qPCR) assays for the detection of swine-associated Bacteroidales genetic markers(gene 1-38,gene 3-53) in the Yangtze Delta watershed of southeastern China.The results indicated that the gene 1-38 and 3-53 markers exhi...  相似文献   
363.
基于LabVIEW软件平台,利用虚拟仪器优势,自主研发了一套用于矿山的微震实时监测系统.介绍了该系统的功能和用途.一段时间现场监测的结果表明,该系统能很好地完成微震实时监测,分析并精确定位微震事件的时间与空间.  相似文献   
364.
SRDAAR-QNPP:acomputercodesystemforthereal-timedoseassessmentofanaccidentreleaseforQinshanNuclearPowerPlantHuErbang;WangHan(Ch...  相似文献   
365.
Direct detection of the fragile X mutation by DNA analysis has greatly simplified prenatal diagnosis of this disease. However, women carrying a fragile X premutation may pass their expanded trinucleotide repeat to sons without expansion to a full mutation. Such sons are predicted to be intellectually normal. In this situation, the accuracy with which the fetal status can be inferred from analysis of chorionic villus sample (CVS) DNA is unclear. We describe such a case, in which it was felt necessary to proceed to fetal blood sampling despite technically unambiguous DNA results from the CVS. The lack of prospective data means that this dilemma may be expected to recur over the next few years when performing prenatal diagnosis on fragile X premutation carriers.  相似文献   
366.
367.
An Erratum has been published for this article in Prenatal Diagnosis 22 (5) 2002, 451. Preimplantation genetic diagnosis (PGD) requires the combined efforts of geneticists and workers in the field of reproductive medicine. This was studied on the basis of a questionnaire, sent to 35 members of the PGD Consortium of the European Society of Human Reproduction and Embryology (ESHRE). A reply was obtained from 20 centres. They represent the majority of activities in the field of PGD in the world. It is obvious that many of the activities (in vitro fertilisation, embryo culture and biopsy) take place in IVF units while others (counselling and diagnosis) are the responsibility of genetic diagnostic centres. The distances between both units vary considerably. In all but one centre sex determination is offered. Aneuploidy screening is offered in 13 out of 20 centres. PGD of translocations and other structural chromosome abnormalities is offered in all but one centre. The number of monogenic diseases offered varies considerably. In comparison to prenatal diagnosis PGD is more expensive. The majority of these costs are due to the IVF or ICSI procedure. The charges for PGD vary between about € 600 and € 4000. In 16 out of 20 centres the parents to be must sign an informed consent form. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
368.
The present study was undertaken to evaluate a nested polymerase chain reaction (PCR) for detection of Y chromosome-specific fetal DNA in maternal plasma and urine of pregnant women during different gestational stages. DNA isolated from plasma and urine samples of 80 pregnant women (between 7 and 40 weeks' gestation) underwent amplification for Y chromosome-specific 198 bp DNA by nested PCR. The postpartum analysis of fetal gender showed that 55 women carried male and 25 female fetuses. Among the 55 women bearing male fetuses, Y chromosome-specific signals were detected in 53 (96%) plasma and 21 (38%) urine samples. Moreover, out of 25 women bearing female fetuses, 3 (12%) and 1 (4%) women had Y chromosome-specific signal in plasma and urine, respectively. Analysis of results with respect to gestational age revealed that there was no significant difference in the detection of Y chromosome-specific DNA between different trimesters in maternal plasma of women bearing male fetuses. These results showed that fetus-specific DNA was detected with high sensitivity (96%) and specificity (88%) in the maternal plasma by nested PCR, and therefore the method could be useful as a non-invasive procedure for fetal sex determination and prenatal diagnosis. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
369.
食品企业污水中含有各种无机污物和有机污物.其中夹带的致病菌将导致多种疾病的爆发和流行.严重威胁着人类的健康。传统的细菌分离、培养和鉴定技术操作繁琐且耗时长(一般需4~7d)。为了快速.准确地检测食品企业污水中存在的细菌,建立了一种采用基因芯片技术对食品企业污水中常见细菌检测和鉴定的实验方法(需时4h)。实验中设计了8对特异引物并成功分成2组混合引物进行多重PCR反应:BI物Ⅰ为Kp+HlyA+InvA+ipaH,引物Ⅱ为Cadc+Oprl+Ent+23SrRNA。效果良好。实验确定了适宜的PCR反应循环数为35个循环,适宜的杂交温度为48℃。用实验制备的基因芯片对模拟水样检测结果的准确率达100%,说明该基因芯片对目的细菌特征基因的检测结果是可靠的。用该方法对食品企业污水水样进行检测具有高准确率,为今后更大规模的检测研究奠定了基础。  相似文献   
370.
Maternal contamination of fetal DNA represents a major problem when highly sensitive molecular techniques are used in the prenatal diagnosis of genetic diseases. For this reason, we have studied the possibility of using DNA isolated from syncytiotrophoblast vesicles as a target of gene amplification (PCR). Three PCR systems were selected which included a repetitive 149 bp fragment of the Y chromosome, the VNTR locus D1S80, and a portion of the β-globin gene. The results of these experiments indicate that DNA isolated from syncytiotrophoblast vesicles is free of maternal contamination and is suitable for gene amplification and DNA analysis.  相似文献   
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