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931.
酚类物质在棉花对枯萎病抗性中的作用 总被引:6,自引:0,他引:6
分析了枯萎病菌侵染及氟乐灵诱发处理后,棉苗叶片和根茎部组织中可溶性酚和黄酮醇以及不溶性细胞结合酚(胞壁结合简单酚、胞壁结合复杂酚聚合物及胞壁结合黄酮醇)含量的变化.结果表明:抗病品种棉苗组织中酚类物质的含量高于感病品种棉苗中的含量,氟乐灵诱发处理促进了棉苗组织中酚类物质的积累;枯萎病菌侵染可明显提高棉苗体内的酚含量,但抗病品种棉苗及经氟乐灵诱发处理并产生诱导抗性的棉苗受侵后其组织中酚含量的增加幅度更大.由此认为,棉花体内的酚类物质与棉花对枯萎病的抗病性以及由氟乐灵诱发的诱导抗性有关. 相似文献
932.
新型多孔高分子载体厌氧流化床启动实验研究 总被引:6,自引:0,他引:6
制备了两种不同孔径(d>0.5μm)分率的聚丙烯酸酯类多孔载体,与多孔颗粒活性炭(GAC)在完全相同的启动条件下,作厌氧流化床固定化微生物对比实验.结果表明:新型高分子载体能有效促进厌氧菌固定化速度,可比GAC缩短反应器启动时间15d左右;扫描电镜观察发现,多孔高分子生物颗粒球形度高,表面生物膜致密坚实,内孔微生物聚集丰富,而GAC生物颗粒形状不规则,表面生物膜疏松呈鳞片状,内孔不易驻留微生物.另外,根据高分子载体内孔产甲烷丝菌的形态和分布特征,获取了当生物膜持续增厚后(δ>100μm),基质扩散阻力影响内孔微生物活性的证据. 相似文献
933.
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
934.
935.
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
936.
937.
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
938.
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
939.
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
940.
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