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污染土壤中多环芳烃生物降解的调控研究 总被引:23,自引:6,他引:17
选用温度、湿度、表面活性剂TW80和CNP比4个因素为调控因子,采用正交法进行周期为150天的实验研究.结果表明,30天后,土壤中PAHs的降解率可达44.5~74.6%,60天后,达70.4~93.7%,降解率的不同与调控条件显著相关.在此期间,降解最佳条件为40℃,湿度25%,CNP比为120101,TW80分别为200~500mg·kg-1.实验结束时,土壤中PAHs的降解率达91.2~99.8%.降解的最佳条件是40℃,湿度15%.经R值判别表明,不同时期各因子对PAHs降解影响有所不同.温度对PAHs降解影响较大,表面活性剂对土壤中PAHs的生物降解有调控作用. 相似文献
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植物法生物修复PAHs和矿物油污染土壤的调控研究 总被引:69,自引:7,他引:62
选择苜蓿草为供试植物,以污染物含量水平、专性细菌和真菌及有机肥为调控因子,进行了植物法生物修复多环芳烃(PAHs)和矿物油污染土壤的调控研究.结果表明,PAHs和矿物油的降解率与有机肥含量呈正相关,增加有机肥5%,可提高矿物油降解率17.6%~25.6%,PAHs降解率9%.在植物存在条件下,土壤微生物降解功能增强.多环芳烃总量的平均降解率比无植物对照土壤提高2.0%~4.7%.投加特性降解真菌可不同程度地提高土壤PAHs总量和矿物油的降解率.真菌对萤蒽、芘和苯(a)蒽/艹屈的降解有明显促进作用.而细菌能明显提高苊稀/芴、蒽和苯(a)萤蒽/苯(k)萤蒽的降解率. 相似文献
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高氧预适应对大鼠心肌缺血损伤时抗氧化酶的影响 总被引:1,自引:0,他引:1
抗氧化酶具有减轻心肌缺血再灌注损伤的作用,在抗氧化酶中,比较重要的是超氧化物歧化酶(SOD),谷胱甘肽过氧化物酶(GlutathionePeroxidase,GSHpx)和过氧化氢酶(CAT)。为了解高氧预适应(HyperoxicPreconditioning,HOP)对大鼠心肌缺血损伤时抗氧化酶的影响,本实验将实验组大鼠放入高压氧舱内,每日吸80-85%氧气(1atm,15-20%为氮气)6h,连续7d。利用Langendorf装置做成心肌缺血再灌注模型。实验动物随机分为二个部分。第一部分可逆性心肌缺血(HOPA组与对照A组):缺血10min,再灌注60min。观察冠脉回流液中SOD活力,检测心肌内抗氧化酶活力(SOD,GSHpx,CAT)。第二部分不可逆性心肌缺血(HOPB组与对照B组):缺血60min,再灌注60min。测定冠脉回流液中肌酸磷酸激酶(CPK)含量,SOD及心肌内抗氧化酶活力。结果表明:对于可逆性心肌缺血:SOD,GSHpx活力升高;对于不可逆性心肌缺血损伤:HOP能减少CPK释放,SOD活力升高。 相似文献
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变灰青霉固态发酵降解植酸的初步研究 总被引:7,自引:0,他引:7
从发霉植酸钠溶液中分离到一株产植酸酶的变灰青霉(Penicilliumcanescens)P4。以麸皮:玉米面:黄豆饼粉=7:2:1为主要培养基成份,用优选法确定最适培养基为在上述基本培养基中添加4%(NH4)2SO4,1%葡萄糖,1.5倍水,自然pH。发酵过程的动态分析表明,该菌在上述条件下28℃恒温培养6d后植酸降解率可达90%;无机磷含量由0.13%增至0.57%;可溶性蛋白含量由3.80%增至7.60%。用4%CaCl2·2H2O水溶液抽提 相似文献
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慢性乙醇摄入大鼠肝脏醇脱氢酶和谷胱甘肽硫转移酶活性影响 总被引:1,自引:0,他引:1
为探讨长期摄入乙醇大鼠肝脏ADH和GST活性的动态变化,旨在为酒精中毒的发病机理提供实验依据,进行了下述实验研究。选用体重100~120gSD雄性大鼠48只,随机分成两组:(1)对照组:24只喂普通饲料,饮用自来水,(2)乙醇组:24只白天饮用10%蔗糖水,夜间饮用105乙醇水溶液,平均每只实验动物的乙醇摄入量为8.0g/kg体重/d,饲料同对照组。实验开始后的30d、60d时分批处死动物,第90天时处死全部动物,除肉眼观察肝脏形态学改变外,同时留取病理标本和进行组织中ADH和GST活性测定,结果显示:(1)大鼠肝细胞胞浆中ADH活性,在服用乙醇30d时即可看到明显减低,较对照组有显著差别(P<0.05),至实验90d结束时,其减低的更明显(P<0.01).(2)大鼠肝细胞胞浆中GST活性 在60d和90d时乙醇组较对照组均明显减低,经统计学处理均有显著差别(P<0.01)。上述结果提示肝脏ADH和GST活性表达在酒精性肝病发病机制中起着重要作用。 相似文献
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白浆土-植物系统营养物质转化机制及其有效性研究Ⅱ.白浆土无机磷形态变化 总被引:1,自引:0,他引:1
采用室内培养和微区试验研究表明,施入白浆土中无机磷在短时间内(24h、8d)主要向FeP和AlP转变,较长时间后(80d),AlP向FeP转化,CaP变化较弱,土壤中无机磷形态转化与白浆土本身的土壤属性具有密切关系.施用有机肥改变了土壤中无机磷形态的转化过程,其与土壤中的铁、铝氧化物反应形成的“Al有机质P”和“Fe有机质P”是作物较易利用的有效P源 相似文献
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黑莓叶片对水分处理的生理反应 总被引:11,自引:4,他引:7
黑莓(Rubus spp.)赫尔(Hull)品种扦插苗在土壤相对含水量分别为85%以上、70% ̄80%、50% ̄60%、45% ̄50%和30% ̄35%的条件下处理20d,以土壤相对含水量70% ̄80%的处理为对照,测定其叶片单个复叶的鲜重,单位叶面积鲜重、叶片相对含水量、叶绿素含量及可溶性蛋白质含量的变化。结果表明:当土壤相对含水量达85%以上时,所测各项指标与对照相比均无显著差异,黑莓生长良好, 相似文献
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产二十二碳六烯酸等多不饱和脂肪酸真菌的筛选 总被引:25,自引:1,他引:24
从土壤中筛选出一株产二十二碳六烯酸(DHA)的丝状真菌,菌丝含油21.23%,DHA占总脂肪酸2.51%;同时含二十碳五烯酸(EPA0,占总脂肪酸的0.41%;不饱和脂肪占总脂肪酸的80%。经鉴定为头孢霉属(Cephalosporium sp.)真菌。同时发现两株菌含EPA,经鉴定为小克银汉霉(Cunninghamella sp.)和毛霉(Mucor sp.)。在这几个属中发现DHA和EPA尚属首 相似文献
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Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m−2 s−1 . It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to Pfr . 相似文献
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通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一. 相似文献
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M. V. Kozlov V. V. Urnysheva L. N. Shishkina 《Journal of Evolutionary Biochemistry and Physiology》2008,44(4):470-475
A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids. 相似文献
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Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H2-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H2 with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD+, FMN+, and NAD(P)+ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H2OCO2+2H++2e- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation 相似文献
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Lee JC 《Acta biochimica et biophysica Sinica》2008,40(7):663-669
Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)8 barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)8 structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive ET and active ER . These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive ET and active ER represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery. 相似文献
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(鱼句)亚科花(鱼骨)型鱼类骨骼系统的比较 总被引:2,自引:0,他引:2
对我国花型Hemibarbuspattern鱼类作了骨骼系统比较,结果表明,此类型鱼类脑颅较长,副蝶骨平直或稍弯曲,眶蝶骨腹纵嵴发达(铜鱼Coreius septentrionalis例外),下颞窝和咽突中等大,基枕骨后突发达;脑颅中的上筛骨的后突、侧筛骨的外筛突,蝶耳骨的外突、上耳骨的后突、围眶骨和后颞窝等均有明显的差异;咽颅中的舌颌骨、尾舌骨、鳃盖骨和下咽齿的列数等又有显著的区别;附肢骨骼中的腰带骨、脊椎骨中的复合神经骨和第4椎骨腹侧的悬器等也有不同之处。据此,这些差异和区别可作为属间或种间的分类依据。 相似文献
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真菌类遗传学分析的知识结构教学 总被引:5,自引:2,他引:3
本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。
Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching. 相似文献
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Henry P. Schwarcz Brian S. Chisholm Meghan Burchell 《American journal of physical anthropology》2014,155(3):460-468
In 1982, Chisholm et al. used δ13C data for human burials from shell midden sites widely distributed on the coast of British Columbia (BC) to show the extreme dependence of these individuals on high trophic level marine consumers, principally salmon and marine mammals. Here, we present previously unpublished analyses of δ15N for some of the same individuals as well as δ13C data for additional individuals. Nitrogen isotope data show that the diet was dominated by high trophic level marine fauna including carnivorous fish and marine mammals. Although most burials were found in shell middens, marine mollusks made up of only a minor component of diet. The data for δ13C demonstrate that terrestrial faunal foods are undetectable in the diet of the majority of individuals, and seldom constitute more than 10% of the dietary protein of individuals living on the coast although terrestrial fauna were widely available as a potential source of protein. This dietary pattern of exclusion of land‐based animals from their diet persisted for almost 6,000 years along a wide expanse of coastline. In contrast, people from the BC interior (100 km or more from the coast) consumed a mixed diet of terrestrial and marine foods including spawning salmon. Am J Phys Anthropol 155:460–468, 2014. © 2014 Wiley Periodicals, Inc. 相似文献