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1.
活性污泥微型动物种群动态与水质净化效能的关系   总被引:12,自引:0,他引:12  
2001~2002年,系统地研究了高碑店污水厂四系列曝气池活性污泥中的微型动物种群动态与水质变化的相互关系。在该污水处理系统的四系列曝气池内所发现的122种原生动物中,褶累枝虫(Epistylis plicatilis)、沟钟虫(Vorticella convallaria)、有肋檐纤虫(Aspidisca costata)和半圆表壳虫(Arcella hemisphaerica)是经常大量出现的原生动物种类。冬季褶累枝虫占绝对优势。5月和6月,有肋檐纤虫为活性污泥动物群落的优势种群。纤毛虫和后口动物总数越多,污水净化效能越强,污泥的沉降性越好。游泳类纤毛虫总数与出水BOD5值呈正相关,固着类纤毛虫的多样性值与出水的总氮呈正相关,爬行类纤毛虫的多样性值与出水的硝态氮和出水总磷都呈正相关,与厌氧段总磷呈负相关。研究结果表明,微型动物种群动态规律与污水处理效果关系密切,该厂污水处理系统中四系列的硝化和反硝化显著,活性污泥的运转效能良好,各种主要污染物得到有效净化[动物学报49(6):775~786,2003]。  相似文献   

2.
对顺德区五种人工林群落物种多样性与立地条件、胸径关系进行了定量研究.结果表明,(1)郁闭度与乔木物种多样性呈显著正相关;(2)土壤因子中代换性Ca2+、pH、NO3-、代换性Mg2+对物种多样性与均匀度有显著影响,并建立了回归方程;(3)树高与乔木层物种多样性呈显著相关,与其它各层相关性不显著;(4)胸径变化趋势较复杂,乔木层S指数与胸径有显著相关,灌木层与胸径相关性不显著,草本层SP、PIE指数与胸径有显著相关性.  相似文献   

3.
采用方差比率法(VR)、X^2检验、无中心指数等方法对缙云卫矛(Euonymus chloranthoides)3个群落进行了群落物种间关联性分析。结果表明,3个群落内物种的总体关联均表现为不显著的负关联性;北温泉群落6个主要物种的15个种对中有7个正关联,8个负关联;鸡公山群落8个主要物种的28个种对中有11个正关联,16个负关联,1个相对独立的关系;东温泉群落4个主要物种的6个种对中2个正关联,4个负关联。这反映了整个群落处于不稳定状态,这与生境片断化是密切相关的。种对间的关联性表明缙云卫矛与慈竹间显示出较强的正关联性,这表明缙云卫矛的生长需要慈竹为其提供适宜的生境。  相似文献   

4.
An agglutinin activity which was sensitive to lactose and heparin was estimated during prenatal brain development. The agglutinin showed higher specific activities in cerebral cortex and midbrain. There was an increase in lectin specific activity in all the brain regions with development. In addition to brain, other fetal organs also showed the presence of developmentally regulated agglutinin. Cerebral cortical agglutinin was purified by Sepharose CL-6B gel filtration and asialofetuin- and heparin-Sepharose affinity chromatography. Purified agglutinin was strongly inhibited by lactose, asialofetuin, and heparin. It showed no requirement for divalent cations and was maximally active at pH 8.0. Electrophoretic characterization showed the aggregate nature of the agglutinin, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis gave subunit molecular weights of 58,000, 45,000, and 24,000.  相似文献   

5.
Mango sap (latex), a by-product in mango industry, was separated into upper non-aqueous phase and lower aqueous phase. Aqueous phase contains very low protein (4.3 mg/ml) but contains high specific activities for peroxidase and polyphenol oxidase. The aqueous phase of sap was subjected to ion-exchange chromatography on DEAE-Sephacel. The bound protein was separated into three enzyme peaks: peak I showed peroxidase activity, peak II showed polyphenol oxidase activity and peak III showed activities against substrates of peroxidase as well as polyphenol oxidase. On native PAGE and SDS-PAGE, each peak showed a single band. Based on the substrate specificity and inhibitor studies peak III was identified as laccase. Although they showed variations in their mobility on native PAGE, these enzymes showed similar molecular weight of 100,000 ± 5000. These enzymes exhibited maximum activity at pH 6 however, polyphenol oxidase showed good activity even in basic pH. Peroxidase and polyphenol oxidase showed stability up to 70 °C while laccase was found to be stable up to 60 °C. Syringaldazine was the best substrate for laccase while catechol was the best for polyphenol oxidase. Thus, mango sap a by-product in mango industry is a good source of these phenol oxidases.  相似文献   

6.
实验研究了三疣梭子蟹(Portunus trituberculatus)卵巢发育过程中(Ⅰ—V期)组织色泽、类胡萝卜素组成与含量、抗氧化和非特异性免疫指标的变化规律,进一步探讨了肝胰腺中类胡萝卜素含量变化与抗氧化指标的关系。结果表明:(1)卵巢发育期间,卵巢指数(GSI)显著增加(P<0.05),肝胰腺指数(HSI)整体呈先升后降的趋势;卵巢的红度(a*)值和黄度(b*)值、肝胰腺的亮度(L*)值和b*值均呈显著上升趋势,但卵巢中L*值呈下降趋势。(2)在卵巢发育过程中,卵巢中的总类胡萝卜素、虾青素、叶黄素和β-胡萝卜素含量均为先升后降的趋势,虾青素含量在Ⅳ期最高;肝胰腺中的虾青素含量呈上升趋势,而β-胡萝卜素含量为显著下降趋势;内表皮中的总类胡萝卜素、虾青素、叶黄素、海胆烯酮和β-胡萝卜素含量均呈现下降趋势;就不同组织中类胡萝卜素含量而言,内表皮中虾青素含量最高。卵巢和肝胰腺的L*值与总类胡萝卜素含量呈显著负相关,卵巢的a*值和b*值均与总类胡萝卜素、虾青素、叶黄素、海胆烯酮和β-胡萝卜素含量呈显著正相关。肝胰腺的a*值与各类胡萝卜素含量无显著相关性, b*值仅与虾青素含量呈显...  相似文献   

7.
摘要:为了验证IPT基因在新麦草中的功能,研究以DT型和ST型的新麦草分蘖节为材料,通过RNA-seq分析和qRT-PCR试验验证IPT的相对表达量并进行GO富集分析,采用PCR法克隆IPT基因,构建1300-cYFP-IPT过表达载体,并进行生物信息学分析;通过烟草瞬时转染法和蛋白质印迹法鉴定IPT蛋白的亚细胞定位及表达情况。结果显示:IPT与tRNA二甲基烯丙基转移酶活性相关,在新麦草分蘖中起上调作用;克隆得到新麦草IPT基因全长,并构建了1300-cYFP-IPT过表达载体,其开放阅读框(ORF)为1362bp;多序列比对与保守结构域分析表明,新麦草IPT蛋白存在PLN02840蛋白保守结构域,与二粒小麦、小麦及硬粒小麦IPT蛋白的亲缘关系较近;蛋白质二级结构预测显示新麦草IPT蛋白二级结构由α-螺旋、延伸链、β-折叠和不规则卷曲组成;分析显示丝氨酸的磷酸化位点最有可能是蛋白发挥功能的潜在磷酸化位点;烟草瞬时转染显示IPT蛋白正常表达,定位于叶绿体中;Western blot结果显示连接载体的目的蛋白IPT正常表达,大小为76.8kDa。研究表明IPT基因在新麦草分蘖过程中上调分蘖数,1300-cYFP-IPT载体可在植株叶绿体中正常表达;该研究为后续新麦草IPT基因进一步功能验证提供试验材料和理论依据。  相似文献   

8.
对不同浓度乙二醇水溶液影响木瓜蛋白酶水解酪蛋白的催化活性及构象的改变进行研究。结果表明,木瓜蛋白酶在乙二醇水溶液中水解酪蛋白的活性显著下降。动力学测定表明,木瓜蛋白酶在乙二醇水溶液中最大反应速度明显下降;差示光谱显示,在乙二醇水溶液中木瓜蛋白酶的二级结构发生了变化;荧光发射光谱显示,木瓜蛋白酶在乙二醇水溶液中发射峰位几乎没移动,但发射强度明显增高。  相似文献   

9.
甘肃敦煌西湖湿地芦苇群落种间关联性研究   总被引:1,自引:0,他引:1  
为了探明甘肃敦煌西湖湿地芦苇群落的物种组成和种间关系,在对其植物群落进行样方调查的基础上,通过2×2列联表,采用方差分析、χ2检验、Ochiai指数、Dice指数和Jaccard指数对甘肃敦煌西湖湿地芦苇群落8个主要物种组成的28个种对间的关联性和相关关系进行了深入分析研究。结果表明:(1)芦苇群落总体间的关联性表现为显著正关联。(2)在28对种对中,有20对显示为正关联,占总关联对数的71.4%;有8对显示负关联,占总关联对数的28.6%。(3)芦苇群落种对间多呈正关联,正负关联的对数比为2.5,正关联占优势,但关联性较弱,负关联数较少,但关联性较强;28种物种对之间关联程度及共同出现概率不高,多数表现为无关联。  相似文献   

10.
The paper aims to study the serological and genetic characteristics of a case of para-Bombay Amh. The serological method was applied to identify the proband's ABO phenotype and PCR-SSP assay was used to analyze the genotype of the para-Bombay blood. DNA sequencing of the PCR products of the first exon of FUT1 gene was used to analyze the genotype and nucleic acid sequence mutation. The serological results showed that the ABO phenotype of the proband was O-type. However, while after absorption-elution test, the ABO phenotype showed weak A-type. The serological test also showed that the irregular antibody anti-H was positive. PCR-SSP assay showed that the proband was h4 para-Bombay type and sequence analysis showed a point mutation c.35C > T of FUT1 gene. The study suggests that genetic analysis is necessary for blood typing in those who have elusive immunological typing results.  相似文献   

11.
Abstract— —The gross distribution of LDH and MAO was studied in a caudo-cranial series of 50 μ thick sections through the medulla oblongata and cerebellum. In general, LDH exhibited a stronger reaction in the neuropil and in the perikarya, whereas MAO showed moderate activity in the neurons and mild to moderate activity in the neuropil. The axonal processes and nerve fibres showed comparatively stronger MAO activity. The nuclei gracilis, cuneatus medialis and lateralis, cranial nerve nuclei, olivaris inferior, vestibularis and cochlearis nuclei showed particularly strong LDH and equally weak MAO activities. The lateral part of the formato reticularis myelencephali showed much more MAO than did the medial part, whereas the LDH reaction was uniformly strong. The reticularis lateralis showed uniformly strong LDH and very mild MAO activities.
In the cerebellar cortex, the MAO activity was concentrated in the molecular layer and nerve fibre layer, whereas LDH activity was particularly strong in the Purkinje cells and their processes in the molecular layer. The cerebellar nuclei showed strong LDH and weak MAO in the neutrons and stronger MAO and moderate LDH in the neuropil.  相似文献   

12.
利用光镜组织化学反应对中华鳖肾单位的结构和组织化学特性进行了详细的观察和分析。结果表明,中华鳖肾脏为分叶形的实质器官,肾小叶由被膜和实质组成,实质无髓质和皮质之分,但可以区分为外侧区和内侧区。外侧区嗜酸性,主要分布有近端小管和集合管。内侧区呈弱嗜酸性,肾小体、颈段、中间段和远端小管主要分布在内侧区。肾小球PAS反应呈阳性,但其琥珀酸脱氢酶(SDH)弱阳性,碱性磷酸酶(ALPase)、Na+/K+-ATPase和阿利新兰(AB)反应为阴性。足细胞酸性磷酸酶(ACPase)反应呈阳性。近端小管刷状缘嗜伊红,PAS反应以及ALPase、ACPase和Na+/K+-ATPase酶反应呈阳性,而SDH弱阳性。中间段、远端小管、集合管弱嗜酸性,SDH阳性。中间段Na+/K+-ATPase弱阳性。远端小管细胞侧面呈PAS阳性,腔面显示AB阳性。集合管胞质含有许多ACPase阳性颗粒,腔面呈PAS强阳性,AB阳性。甲苯胺兰(TB)染色可见集合管腔面有阳性颗粒,肾小管上皮含有亮、暗两种细胞。上述组化反应和分布结果表明,鳖的肾小管细胞类型较多,近端小管在原尿的重吸收中起主要作用,远端小管和集合管具有分泌黏液作用。中华鳖肾单位的结构与组化特性不仅与哺乳类和鸟类有一定差异,也与其他爬行动物不完全相同。    相似文献   

13.
灰霉病是月季采后和运输过程中危害最严重的真菌病害.MPK3基因参与植物对逆境的响应.基于古老月季品种'月月粉'(Rosa chinensis'Old Blush'Jacq.)全基因组数据,利用RT-PCR技术获得了包含完整ORF区的RcMPK3基因,并对其进行生物信息学分析和功能检测.结果显示:RcMPK3基因ORF序...  相似文献   

14.
过表达Dbtnbt基因提高中国红豆杉细胞的紫杉醇含量   总被引:1,自引:0,他引:1  
本文通过克隆3′-N-去苯甲酰紫杉醇N-苯甲酰转移酶(3′-N-debenzoyltaxol-N-benzoyltransferase,DBTNBT)基因Dbtnbt,构建其表达载体p1303-SDbtnbtN,转化中国红豆杉细胞,经潮霉素抗性筛选获得转基因细胞系. 转基因细胞分析结果表明,T-DNA及其包含的基因与宿主细胞染色体成功整合;转基因细胞中报告基因GusA-mgfp5正常表达;转基因细胞的Dbtnbt mRNA表达量是未转化细胞的1.33 倍;转基因细胞的紫杉醇产量约为27.3 μg/g,是未转化细胞的1.37倍. 本研究结果表明,过表达Dbtnbt基因将中国红豆杉细胞的紫杉醇产量提高约37%.  相似文献   

15.
对丹参EST数据库进行BLAST同源性比对发现,登录号为CV165156的EST序列与硫氧还蛋白基因(Trx)有很高的同源性。进一步用PCR方法从丹参基因组水平上克隆到长1806bp的DNA序列(登录号为FJ217699),与cDNA序列比对发现,该基因(SmTrxh)含有2个内含子。生物信息学分析表明,SmTrxh所编码蛋白的分子质量为13.4kDa,理论等电点为5.53,无信号肽,属于定位于细胞质中的稳定类蛋白。该蛋白与其他7种植物中的Trx高度同源,同源性介于68%-74%之间。实时定量PCR检测的结果显示,SmTrxh在丹参中为组成型表达基因,在根、茎和叶中都有表达,主要在根部表达,茎中的表达量最低。  相似文献   

16.
MAX1(MORE AXILLARY GROWTH1)是独脚金内酯(Strigolactones,SLs)合成途径中的关键基因,为了研究MAX1在苹果分枝调控中的功能,以苹果‘长富2号’(Malus domestica‘Nagafu 2’)腋芽为材料,采用PCR方法,克隆MdMAX1基因,进行生物信息学和表达水平分析;采用瞬时表达转化烟草,进行GUS染色,分析MdMAX1启动子活性。结果表明:(1)成功克隆得到苹果MAX1,其开放阅读框(ORF)1620 bp,编码539个氨基酸;系统进化和基序分析表明,MdMAX1和已知的A1型MAX1相似。(2)qRT-PCR分析表明,MAX1基因在‘长富2号’嫁接苗茎中高表达,并在腋芽本身有表达;RNA-seq分析表明,细胞分裂素(6-BA)处理苹果腋芽96 h后MAX1基因的表达水平显著降低。(3)成功克隆获得‘长富2号’MAX1启动子序列片段(1500 bp),顺式作用元件预测显示MdMAX1启动子序列中存在光响应元件,GUS活性分析表明光照处理能够减弱MAX1启动子的活性。该研究为进一步研究苹果MAX1参与SLs合成、调控苹果分枝的功能奠定了基础。  相似文献   

17.
A carboxylesterase activity (E.C.3.1.1) was found in all four strains of Acinetobacter calcoaceticus tested. The activity was present in both 2 X 10(4) gav h-1 supernatant and bacterial wall-membrane fractions. The activity in the supernatant was in two molecular weight forms, the predominant form with a Mr of about 10(3) K and a minor form Mr approximately 600 K. The activity was inhibited by phenylmethylsulfonyl fluoride. SDS-PAGE showed that in A. calcoaceticus NCIB 8250 the activity was composed of three components of Mr 43, 40 and 38 K. The individual components showed different activities with 1- or 2-naphthyl esters. Of the other strains used, one showed a nearly identical pattern of component activities, while the other two showed only two component activities.  相似文献   

18.
During a survey conducted in Colombia a new isolate of Bacillus thuringiensis that showed toxicity toward Culex quinquefasciatus, Cx. pipiens, Aedes aegypti, and Anopheles stephensi larvae was isolated. Parasporal crystals were spherical in shape and showed a great degree of similarity with those produced by the reference strain of Bacillus thuringiensis subsp. israelensis. Supernatant fraction of the whole culture was not toxic, and heat-stable exotoxin production was negative. Catalase, urease, arginine dihydrolase, amylase, lecithinase, acetyl-methyl-carbinol, and gelatinase production were positive. Hemolysis on sheep blood agar was alpha-type. The isolate 163-131 showed natural resistance to azolocillin and was sensible to cephoperazone, cephalotin, nalidixic acid, and trimetoprin sulfametoxazole. Flagellar agglutination showed a specific H 30 antigen which allows individualization of this strain as a new serotype and the subspecies name of medellin is proposed.  相似文献   

19.
Adipose tissue-derived stem cells (ADSC) are isolated from the stromal vascular fraction (SVF) of adipose tissue and considered an excellent cell source for regenerative medicine. During the isolation and propagation of several human ADSC cell lines, we observed the emergence of an unusual cell line designated HADSC-6. Although initially fibroblast-like as typical ADSC are, HADSC-6 cells became homogeneously cuboid in shape, had very little cytoplasm, and formed aggregates with capsule-like boundary. Proliferation assay showed that HADSC-6 grew much faster than typical HADSC cell lines, such as HADSC-20. Immunocytochemistry showed that HADSC-6 did not express endothelial markers CD31 and vWF, and matrigel tube formation assay showed that it was unable to form endothelial-like tube structures. However, LDL uptake, a reliable endothelial marker, was positively identified. Chromosomal analysis showed that HADSC-6 cells were hypertriploid, and soft agar colony formation assay showed that they were able to proliferate and form large colonies in an anchorage-independent manner. However, tumorigenicity test showed that HADSC-6 was unable to form tumors in athymic mice. RT-PCR analysis showed that both HADSC-6 and HADSC-20 expressed VEGF-A, VEGF-B, VEGF-D, and VEGFR1 but not VEGFR2 or VEGFR3. VEGF-C, however, was expressed at a high level in HADSC-20 but undetectable in HADSC-6. In the IGF system, IGF-1 was abundantly expressed in HADSC-20 but marginally detectable in HADSC-6, and IGF-1R was abundantly expressed in HADSC-6 but not detectable in HADSC-20. In the FGF system, bFGF was abundantly expressed in HADSC-20 but marginally detectable in HADSC-6, and FGFR1 was abundantly expressed in both. Taken together, these results suggested that HADSC-6 cells were spontaneously transformed from the endothelium; therefore, they were further compared to previously published data of four naturally occurring human angiosarcoma cell lines. The results showed that the established angiosarcoma cell lines exhibit considerable variations among themselves and HADSC-6 displayed most of these variable characteristics.  相似文献   

20.
The paper aims to study the serological and genetic characteristics of a case of para-Bombay Amh . The serological method was applied to identify the proband''s ABO phenotype and PCR-SSP assay was used to analyze the genotype of the para-Bombay blood. DNA sequencing of the PCR products of the first exon of FUT1 gene was used to analyze the genotype and nucleic acid sequence mutation. The serological results showed that the ABO phenotype of the proband was O-type. However, while after absorption-elution test, the ABO phenotype showed weak A-type. The serological test also showed that the irregular antibody anti-H was positive. PCR-SSP assay showed that the proband was h4 para-Bombay type and sequence analysis showed a point mutation c.35C>T of FUT1 gene. The study suggests that genetic analysis is necessary for blood typing in those who have elusive immunological typing results.  相似文献   

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