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941.
应用ICP-MS直接测定近岸高盐排污口水样中重金属方法研究 总被引:2,自引:1,他引:2
利用带八极杆碰撞/反应池(ORS)和屏蔽炬技术的电感耦合等离子体质谱(ICP-MS)直接测定近岸高盐排污口样品中的V、Cr、Mn、As、Mo、Ag、Cd、Pb、Th和U等多种重金属元素.通过向碰撞池中引入He气,消除高盐基体可能带来的多原子离子干扰.样品用1%HNO3稀释后直接测定,用标准物质进行方法验证,连续分析样品4h,以检验仪器的长期稳定性.测定绝大多数元素的相对标准偏差在5%以内,加标回收率为88.32%~118.5%. 相似文献
942.
943.
Presumptive maternal cell contamination (MCC) was monitored in identified male cases during cytogenetic comparison of direct techniques and three different culture regimes from 140 thoroughly dissected chorionic villus samples. Of the 66 identified male cases, 11(16·7 per cent) showed MCC, the mean number of cells examined per case being 8·2 (direct) and 14·5 (cultures); in the direct preparations only one of a total of 457 cells examined was female, while preparations from cultures revealed MCC in 11 cases. Four of these had MCC in more than one culture regime and four had only a single female cell. The results showed that (1) dependence on the culture system alone would have given a diagnosis based on maternal cells in one (1·5 per cent) male case, thus underlining the danger of this approach (a similar undetected rate of misdiagnosis being expected in the female cases) and (2) MCC was significantly lower in cultures grown in Chang medium as compared with the other two regimes, McCoy's 5A + 15 per cent fetal calf serum and 1 per cent Ultroser G, and McCoy's 5A + 25 per cent fetal calf serum, the latter expressing the highest level of MCC. 相似文献
944.
945.
微核技术在环境监测中的应用概况 总被引:7,自引:0,他引:7
本文根据近年来我国利用微核技术监测环境污染的研究,对微核技术的基本原理及其生物学意义进行了简要的概述;并介绍了两种常用的植物微核技术-紫露草四分体微核技术和蚕豆根尖细胞微核技术;对目前我国微核技术的发展状况及存在问题进行了初浅的探讨。 相似文献
946.
Maria Lombardo Rita M. Melati Santino Orecchio 《Atmospheric environment (Oxford, England : 1994)》2001,35(36)
The influence of air pollution on the chemical composition of Pinus sp. needles was examined in polluted and control sites in and around the city of Palermo (Sicily). The chemical composition of needles indicated the extent of contamination of the trees, which were cytologically examined. Cell analysis was carried out on pine samples, including needles and pollens, from 15 different locations. Biostructural and spectrophotometric tests were performed. In particular, concentrations of toxic (Cd, Pb) and non-toxic metals (Fe,Cu, Zn) were determined, as well as injury caused by their accumulation in the needles. The more highly urbanised areas showed higher concentrations of metals (Pb, Cu. Zn, Fe); only the concentrations of Cd and Mn turned out to be constant in all the sites. Cell analysis revealed displasic cells and secondary metabolite accumulations in trees from polluted sites. These changes observed were most likely caused by the toxic effect of pollutants. 相似文献
947.
A. Kolialexi C. Vrettou J. Traeger-Synodinos R. Burgemeister N. Papantoniou E. Kanavakis A. Antsaklis A. Mavrou 《黑龙江环境通报》2007,27(13):1228-1232
Single nucleated red blood cells (NRBCs) isolated from maternal circulation were used for prenatal diagnosis of β-thalassaemia. The study included 22 pregnant women in the first trimester, 6 carriers at risk for β-thalassaemia and 16 noncarriers. Methodology involved enrichment of NRBCs by magnetic cell sorting (MACS) and microdissection of single NRBCs with a laser micromanipulation system. Single-cell genotyping based on nested real-time PCR for genotyping β-globin gene mutations was performed followed by a multiplexed minifingerprinting to confirm the origin of the isolated cells and possible contamination. Two polymorphic markers (D13S314 and GABRB3) facilitated the identification of fetal NRBCs through comparison of allele sizes found in the respective parents. In this study, 224 single NRBCs were detached and transferred into individual PCR tubes. Allele amplification in at least one microsatellite marker was achieved in 128/224 cells. Minifingerprinting analysis showed that 22 cells were fetal, 26 maternal and 80 were noninformative due to ADO or homozygosity. In 6 NRBCs the β-globin gene was amplified and in 2, coming from the same pregnancy, only the paternal mutation was detected. The low PCR success when genotyping isolated NRBCs was possibly due to the poor quality of fetal NRBCs and the relatively large size of the β-globin gene product. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
948.
邻苯二甲酸丁基苄酯致小鼠肥大细胞DNA损伤的初步研究 总被引:2,自引:0,他引:2
为探讨邻苯二甲酸丁基苄酯(BBP)对小鼠肥大细胞DNA的损伤作用,采用不同浓度BBP(0、4、20、100μmol·L-1)对体外培养的小鼠肥大细胞染毒60min,应用单细胞凝胶电泳法和KCl-SDS沉淀法检测细胞DNA断裂和DNA-蛋白质交联.结果表明,低、中、高浓度(4、20、100μmol·L-1)的BBP均可引起小鼠肥大细胞DNA损伤,低浓度BBP引起的DNA损伤主要以DNA断裂为主,而中、高浓度BBP引起的DNA损伤主要以DNA-蛋白质交联为主。 相似文献
949.
微囊藻毒素对束丝藻细胞生长和抗氧化系统的影响 总被引:1,自引:0,他引:1
为从活性氧(ROS)角度探讨微囊藻毒素(MC)导致藻类细胞死亡的机理及揭示藻细胞对MC诱发的氧化胁迫的响应机制,采用50和500μg·L-1的微囊藻毒素LR(MC-LR)处理束丝藻(Aphanizomenon sp. DC01)细胞,测定了细胞生长、细胞内活性氧(ROS)含量及抗氧化系统的变化.结果表明,50μg·L-1的MC-LR处理对藻细胞的生长无显著影响,而500μg·L-1的MC-LR处理可诱导藻细胞死亡.50μg·L-1的MC-LR处理的藻细胞ROS含量在处理第2d显著高于对照;但藻细胞能通过还原型谷胱甘肽(GSH)含量,超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GPX)活性改变修复氧化损伤,使ROS水平在处理第3d恢复到对照水平.500μg·L-1的MC-LR处理可显著降低藻细胞GSH含量和SOD与GPX活性,刺激藻细胞生成过量的ROS;ROS在毒素处理4d后突然暴发,过量的ROS引起膜质过氧化,并最终导致藻细胞死亡。 相似文献
950.
有机氯类农药为已确定的环境雌激素,易在体内蓄积产生慢性毒性危害人体健康。选择单一存在时无明显雌激素效应的残留剂量进行联合试验,观察联合作用后雌激素效应的增减。选取乳腺癌MCF-7细胞作为研究对象,对残留剂量下六氯苯(HCB)、β-六六六(β-BHC)和p,p’-滴滴涕(p,p’-DDT)联合后的雌激素效应机制进行了研究。首先,运用MTT法观察3种有机氯类农药残留剂量下单独和联合作用对MCF-7细胞生长的影响;然后,运用流式细胞仪测定有机氯类农药联合对MCF-7细胞周期的影响;之后,采用Western Blot法测定有机氯类农药联合后ERα、ERβ、ERK1/2、p-ERK1/2、Ki67、c-Myc和Cyclin D1蛋白表达的变化。结果显示,β-BHC+p,p’-DDT组、HCB+β-BHC+p,p’-DDT组作用24 h后细胞增殖率为115.0%、120.1%,作用48 h后增殖率为121.2%、126.3%,其他联合组与对照相比未发生明显变化;β-BHC+p,p’-DDT组、HCB+β-BHC+p,p’-DDT组中MCF-7细胞的G1期细胞比例下降,S期细胞比例上升,细胞呈高增殖状态;β-BHC+p,p’-DDT组、HCB+β-BHC+p,p’-DDT组和雌二醇(E2)组作用48 h后,均降低ERα的蛋白表达,升高ERβ的蛋白表达,促进p-ERK1/2、Ki67、Cyclin D1和c-Myc的蛋白表达。研究表明,在单一作用时不具有雌激素效应的残留剂量下,仅β-BHC+p,p’-DDT联合组和HCB+β-BHC+p,p’-DDT联合组具有明显雌激素效应,其效应机制为经雌激素受体途径,激活ERβ蛋白表达,抑制ERα蛋白表达,促进p-ERK1/2、Ki67、c-Myc和Cyclin D1等相关蛋白的表达。 相似文献