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蒽、菲、芘、■混合液对菲律宾蛤仔抗氧化酶活性的影响 总被引：1，自引：0，他引：1
以菲律宾蛤仔（Ruditapes philippinarum）为研究对象，在实验生态条件下采用不同浓度的蒽（Fluoranthene）、菲（Phenaphthene）、芘（Pyrene）、[艹屈]（chrysene）混合液进行染毒实验，研究菲律宾蛤仔体内超氧化物歧化酶（superoxide dismutase，SOD）、过氧化氢酶（catalase，CAT）和谷胱苷肽过氧化物酶（glutathione peroxidase，GPx）的剂量-效应关系和时间-效应关系。实验的3种混合液浓度为5μg／L（低浓度组），50μg/L（中浓度组），500μg／L（高浓度组）。结果表明，在低浓度混合液下（5μg／L），CAT比SOD和GPx更快受到诱导；4种多环芳烃混合污染物对SOD、CAT和GPx活性的影响均为先诱导后抑制的变化过程。 相似文献
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目的：观察益气养阴明目汤对脾肾两虚型大鼠眼视网膜组织中SOD（超氧化物歧化酶）、CAT（过氧化氢酶）、MDA（丙二醛）、NO（一氧化氮）及ET（内皮素）表达的影响。方法：将Wistar大鼠60只（21～32个月龄）随机分为3组：蒸馏水组、对照组（石斛夜光丸）、治疗组（益气养阴明目汤）,每组20只制备成脾肾两虚型模型,灌胃治疗30d。检测大鼠视网膜组织中SOD、CAT、MDA、NO表达水平及眼眶血中ET的含量。结果：治疗组及对照组SOD、CAT含量明显高于蒸馏水组,MDA含量明显低于蒸馏水组,差异均有统计学意义（P<0.01）;治疗组NO含量明显高于蒸馏水组及对照组,差异有统计学意义（P<0.01）,而对照组与蒸馏水组比较,差异无统计学意义（P>0.05）;3组ET含量比较,差异均无统计学意义（P＞0.05）。结论：益气养阴明目汤可提高脾肾两虚型大鼠眼视网膜组织中SOD、CAT及NO的含量,降低MDA含量,可调节大鼠血管内皮功能,促使内皮细胞释放舒血管物质,从而达到扩张血管,改善微循环的作用。 相似文献
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以灭活的嗜水气单胞菌（Aeromonas hydrophila）脂多糖和绣球菌（Sparasis crispa）多糖作为免疫增强剂,对接种免疫后的泥鳅（Misgurnus anguillicaudatus）进行抗氧化性能、免疫功能及消化功能等指标进行测定。结果表明：嗜水气单胞菌脂多糖和绣球菌多糖不仅可以提高泥鳅的抗氧化性能和免疫功能,而且可以增强泥鳅的消化功能,质量浓度为1g／L的灭活嗜水气单胞菌脂多糖和9g／L的绣球菌多糖对泥鳅的作用效果较明显,能较明显地提高泥鳅抗氧化性能、免疫功能及消化功能,与注射灭活的嗜水气单胞菌脂多糖相比,9g／L绣球菌多糖对泥鳅的作用时间更持久。 相似文献
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随着纳米科技的发展及纳米颗粒在纺织、食品、太阳能及水处理等各行业的应用,进入水生环境的纳米颗粒对其中痕量金属的生物地球化学循环及其生物学效应的影响受到关注。本文研究了水环境中分布最广泛的纳米二氧化钛(n-TiO2)对镉(100μg·L^-1)在海洋双壳类菲律宾蛤仔体内生物利用性及生物效应的影响,通过14d的暴露实验,在环境真实浓度下研究Cd在蛤仔体内的蓄积量及毒性。暴露期间测定了蛤仔消化腺中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽S-转移酶(GST)、丙二醛(MDA)和金属硫蛋白(MT)等生物标志物的活性或含量,同时分析了消化腺中Cd的蓄积。暴露3d后,Cd处理组及n-TiO2+Cd处理组均观测到蛤仔消化腺内Cd含量显著升高(p<0.05),并随时间延长而不断升高。各处理组SOD活性在整个暴露周期内与同期对照组相比均无显著差异。CAT(3d)和GST(7、14d)活性仅在Cd处理组出现显著升高(p<0.05)。Cd处理组在暴露结束时出现MDA含量的显著增加;n-TiO2单独及联合处理组MDA含量显著上升出现在7d后,至暴露结束时与对照组无显著差异。随暴露时间的延长,只有Cd处理组中蛤仔消化腺MT的含量呈现显著升高。结果表明,相同浓度条件下,Cd对蛤仔的亚致死毒性高于n-TiO2,而n-TiO2能够通过抑制Cd的生物积累而减轻后者对蛤仔的毒性,这种影响与n-TiO2对Cd的吸附作用有关。 相似文献
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为探讨低温处理对黄姑鱼幼鱼生理机能的影响,以18℃为对照组,设置8℃、10℃和14℃3个低温胁迫组,测定不同温度急性胁迫对黄姑鱼幼鱼(Nibea albiflora)超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、Na~+/-K~+-ATP酶活力以及热休克蛋白70(Hsp70)蛋白含量的影响。研究结果表明,低温胁迫组(8℃、10℃和14℃)的SOD和CAT酶活力随着胁迫温度的降低及其胁迫时间的延长呈先升高后降低的趋势,在72 h时恢复到对照组水平。肌肉中的Na~+/-K~+-ATP酶活力则随处理时间的延长呈现先降低后升高的趋势,10℃和14℃组能够在72 h时恢复到对照组水平,而8℃组则在72 h仍显著低于对照组。低温胁迫下黄姑鱼肌肉的Hsp70含量随着处理时间的延长呈先升高后降低趋势,10℃和14℃组能够在72 h时恢复到对照组水平,而8℃组则在72 h仍显著高于对照组。由此说明,SOD、CAT、Na~+/-K~+-ATP以及Hsp70蛋白参与了黄姑鱼低温胁迫应答过程,可以作为其低温胁迫应答的标志物。 相似文献
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固定化鲅鱼乙酰胆碱酯酶的制备及部分性质测定 总被引：3，自引：0，他引：3
酶的固定化是酶传感器制备过程中重要的1个环节.研究采用直接共价法固定鲅鱼乙酰胆碱酯酶（AChE）.制备方法为：0.1g CNBr活化的Sepharose 4B凝胶用1mmol/L的HCl充分溶胀后,与活力为10U的AChE溶液混合,于4℃下150r/min振荡8h.所制备的固定化酶活力回收率较高（96%）,对pH值和温度变化的适应能力均优于非固定化酶;在3个月保存期内,前者的活力损失13%,而后者的活力则下降89%.这说明固定过程能够大大提高AChE的抗逆性和保持酶活力的稳定,有利于酶传感器的制备. 相似文献
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温度突变对大海马(Hippocampus kuda)幼体生长、组分及酶活力的影响 总被引：1，自引：0，他引：1
以大海马幼体为实验材料,通过设置不同的温度突变组(温度从23℃突变至15℃、28℃和33℃)的方法,对其生长、生化组分以及酶活力的影响进行了研究。结果表明,实验结束后,28℃温度组的大海马幼体生长指标、蛋白含量、能值显著高于23℃对照组(P<0.05),而15℃、33℃温度组的各项指标则显著低于对照组(P<0.05);此外,温度突变组的大海马幼体的酶活力均有先升后降的趋势,在1d后出现峰值,4—6d各个温度组趋于稳定,到实验第15天时,28℃温度组的SOD、ACP活力和MDA的含量已处于23℃对照组水平(P>0.05),CAT、AKP活力显著高于23℃对照组(P<0.05)。而15℃、33℃温度组的SOD、CAT活力降至低于23℃对照组水平(P<0.05),15℃温度组的ACP、AKP活力则低于23℃对照组水平(P<0.05),MDA的含量在15℃、33℃温度组随时间延长而增加。 相似文献
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芽孢杆菌和溶藻弧菌对凡纳滨对虾消化酶、免疫酶活力及抗病力的影响 总被引：1，自引：0，他引：1
《中国海洋大学学报(自然科学版)》2015,(5)
选取初始体重(3.58±0.32)g的凡纳滨对虾,在饲料中分别添加溶藻弧菌(Vibrio alginolyticus)活菌、溶藻弧菌破碎菌、芽孢杆菌(Bacillus sp.)活菌和芽孢杆菌破碎菌和使其菌含量为108 CFU/g,通过49d的养殖实验研究饲料中添加芽孢杆菌和溶藻弧菌对凡纳滨对虾的消化酶、免疫相关酶和抗病力的影响。结果显示:(1)4个处理组对虾的肠道蛋白酶水平均显著提高。25d时各处理组淀粉酶水平均显著高于对照组,49d时弧菌破碎组和杆菌破碎组对虾的淀粉酶水平高于对照组(P0.05),其中杆菌破碎组对虾肠道的消化酶水平最高,杆菌组对虾肠道消化酶水平低于其他处理组。(2)49d时弧菌组对虾的超氧化物歧化酶(SOD)水平上升(P0.05);弧菌破碎组对虾的SOD、酚氧化酶(PO)和抗菌酶水平上升(P0.05);杆菌组对虾PO水平上升,抗菌酶水平下降(P0.05);杆菌破碎组对虾SOD和PO水平均上升,抗菌酶水平下降(P0.05)。(3)WSSV攻毒的半致死时间为杆菌破碎组弧菌破碎组弧菌组杆菌组对照组。研究表明,饲料中添加芽孢杆菌和溶藻弧菌及其破碎菌体均能在一定程度上提高对虾的消化酶活力和抗病力。其中添加弧菌破碎菌体能更好的提高对虾的免疫酶水平,添加杆菌破碎菌体能促进对虾消化和抗病力。 相似文献
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重金属离子对中华绒螯蟹肝胰脏和鳃丝SOD,CAT活力的影响 总被引：14，自引：3，他引：14
研究了 3种重金属离子 (Cu2 ,Zn2 ,Cd2 )对中华绒螯蟹肝胰脏和鳃丝 SOD,CAT活力的影响。实验结果表明 ,肝胰脏和鳃丝 SOD,CAT活力在 3种重金属离子作用下分别随取样时间变化显著 (P<0 .0 5 ) ,对 2种抗氧化酶活力的抑制均为肝胰脏 <鳃丝。 3种重金属离子在实验时间内对肝胰脏 2种抗氧化酶活力的影响呈峰值变化 ,低浓度组表现为促进作用 ,高浓度组在 96 h时为抑制作用 ;低浓度组在 72 h内能提高鳃丝 2种抗氧化酶活力 ,随后下降 ,至 96 h时表现为抑制作用 ,而高浓度组一直为明显的抑制作用 ,2种抗氧化酶活力表现出明显的时间、剂量效应关系。因此 ,肝胰脏和鳃丝SOD,CAT2种抗氧化酶可作为中华绒螯蟹毒理学的评价指标。 相似文献
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Chandralata Raghukumar G. Sheelu P. A. Loka Bharathi Shanta Nair C. Mohandass 《Marine Georesources & Geotechnology》2001,19(1):1-16
In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance. 相似文献
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Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
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Derek V. Ellis 《Marine Georesources & Geotechnology》2001,19(1):51-63
This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested. 相似文献
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G. Parthiban 《Marine Georesources & Geotechnology》2000,18(3):223-235
Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement. 相似文献
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Geoacoustic Inversion via Genetic Algorithm and Its Application to Manganese Sediment Identification
An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm. 相似文献
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海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。 相似文献
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The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments. 相似文献
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Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
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The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
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