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1.
采用生物急性毒性实验的方法，对一株不产PSP毒素的相关亚历山大藻（Alexandrium affine株AC-1）的毒性及其毒素（AFT）成分进行研究。结果表明，相关亚历山大藻（AC-1）对卤虫、轮虫、糠虾均有毒性效应，其96hLC50分别为：90cells／ml，1500cells／ml，5000cells／ml。相关亚历山大藻（AC-1）各组分：藻液、细胞重悬液、藻细胞培养过滤液、内容物对卤虫存活率均有显著影响，表明AFT毒素可能来源于细胞内，能分泌到细胞培养液中。通过对该藻过滤液的热稳定性、酸碱稳定性、去蛋白组分毒性、分子量范围、极性、多糖组分鉴定，表明AFT毒素为极性较强的多糖类物质，对热和酸碱稳定．其分子量范围为5-50kDa。 相似文献
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亚历山大藻溶血毒性的初步研究 总被引：1，自引：0，他引：1
研究了11株亚历山大藻（Alexandrium spp．）的溶血毒性，其中7株亚历山大藻具有显著的溶血毒性，说明溶血毒性在亚历山大藻中具有一定的普遍性，但各亚历山大藻藻株溶血毒性的大小与其所产麻痹性贝类毒素（Paralytic Shellfish Poisoning，PSP）的能力无直接关系；针对性地研究了一株典型PSP产毒甲藻——塔玛亚历山大藻（A．tamarense，ATHK株）的溶血毒性特点，该株亚历山大藻具有较强的溶血毒性，指数期单个藻细胞的溶血毒性大小约相当于4pg皂素的溶血能力，而且其溶血毒性的大小与藻的生长阶段和细胞密度都有一定关系：指数期的溶血毒性最大；藻细胞、细胞碎片、细胞内容物都有一定的溶血毒性，其中细胞碎片的毒性最大；研究还表明一种PSP标准品STX毒素并没有溶血毒性，进一步说明亚历山大藻产生的溶血毒性是其他非PSP物质造成的，这类溶血毒素对人类健康和生态环境的影响值得关注。 相似文献
3.
塔玛亚历山大藻和赤潮异弯藻对黑褐新糠虾和卤虫的急性毒性作用 总被引：9，自引：3，他引：9
以黑褐新糠虾和卤虫为实验材料,研究了两种典型有毒有害赤潮藻,塔玛亚历山大藻和赤潮异弯藻的毒性.结果表明塔玛亚历山大藻和赤潮异弯藻都能影响糠虾的存活,在9 h内塔玛亚历山大藻和赤湖异弯藻对糠虾的半致死浓度分别约为7000和450 000个/cm3;在24 h内塔玛亚历山大藻和赤潮异弯藻对卤虫存活没有显著影响,而赤潮异弯藻能对卤虫的活力产生强烈的抑制作用,0.1,1.5,5和24 h的半抑制浓度分别为15 000,7500,4500,3000个/cm3,但在赤潮异弯藻较低浓度为3000个/cm3时,经过48 h卤虫的运动能力能够恢复到正常水平.结果表明,这两种有害藻对同一种生物的毒性大小存在差异,而这两种甲壳类生物对同一种有害藻的反应也不相同. 相似文献
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塔玛亚历山大藻对海产双壳类生命活动的影响 总被引：4，自引：1，他引：4
通过一种重要有毒赤潮藻——产麻痹性贝毒毒素PSP的塔玛亚历山大藻对几种海产双壳类主要发育阶段:受精卵、D形幼虫、眼点幼虫、稚贝、仔贝和成贝生命活动的影响研究,发现该藻对双壳类孵化率、存活率、运动能力、滤食率和生长都有影响,毒性效应与藻密度有明显的相关关系.该藻对受精卵的抑制作用在100个/cm3的密度下最显著,36h后孵化率仅为对照组的30%.进一步的逐项毒性筛选实验表明此毒性来源于藻液、藻细胞和细胞碎片,而与去藻过滤液、藻细胞内容物、标准毒素STX无关,由此可以证实塔玛亚历山大藻确能产生一类非PSP毒素,并与细胞表面的未知毒素相关. 相似文献
6.
赤潮毒藻塔玛亚历山大藻研究进展 总被引：1，自引：0，他引：1
塔玛亚历山大藻(Alexandrium tamarense)是一种可产生麻痹性贝毒素(PSP)的海洋甲藻,其适应能力强、生存范围广,在中国北至胶州湾、南至厦门海域[1]和大鹏湾[2]都有发现,并有发生赤潮的记录,是重要的赤潮原因生物之一。其所产生的麻痹性贝毒素在一定条件下可通过食物链在鱼类、贝类等生物体内蓄积,对生物甚至人类产生危害,成为影响水产品食用安全的重要因素。同时,海洋生物毒素的高特异性、高活性特征,成为现代研究海洋药物的开发热点。因此,对塔玛亚历山大藻的研究有着重要的现实意义。作者主要综述塔玛亚历山大藻近年来的研究进展。1塔玛… 相似文献
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中国沿海亚历山大藻(Alexandrium)核糖体rDNA部分序列分析及该藻属分子系统进化研究 总被引：4，自引：1，他引：4
分析了几株自南海及东海分离的亚历山大藻的rDNA部分序列信息,其中包括核糖体大亚基(LSU)rDNA的5′端D1-D2区序列,以及5.8SrDNA和ITS区序列;同时也对实验室保种的部分来自其它国家和地区的亚历山大藻相关序列进行了测序和分析,并以此作为序列分析中的参考。采用ClustalX及MEGA2软件对所得到的序列信息进行了综合分析与对比。结果表明,分离自南海的塔玛亚历山大藻(Alexandriumtamarense)和分离自东海的链状亚历山大藻(A.catenella),即便是在ITS区和LSUrDNA等高变区,其序列信息也完全一致。与基因库中搜索到的其它亚历山大藻rDNA序列信息相比较,中国沿海的塔玛/链状亚历山大藻序列更接近于塔玛复合种的“亚洲温带”基因型。对于分离自南海的另外两株未定种的亚历山大藻,通过对比序列信息,发现它们与相关亚历山大藻(A.affine)非常接近。分离于我国台湾地区的微小亚历山大藻(A.minutum)在序列上与分离自新西兰的藻株相似,而与分离自欧洲的微小亚历山大藻藻株相差较大。中国沿海亚历山大藻rDNA序列信息的获得为针对有毒藻种设计特异性核酸探针,发展灵敏快速的生物检测技术奠定了基础。 相似文献
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塔玛亚历山大藻对两种单细胞藻生长的影响 总被引：7，自引：0，他引：7
本文研究了塔玛亚历山大藻(ATCI01品系)细胞再悬浮液、细胞破碎液、上清液、藻壳液、过滤液对亚心形扁藻悬浮性的影响,以及塔玛亚历山大藻与亚心形扁藻和小球藻之间的相互作用.结果发现,含有塔玛亚历山大藻成分的实验溶液均能在短时间内造成亚心形扁藻失去鞭毛形成胞囊而下沉,其中再悬浮液的影响最大.但亚心形扁藻受到的这种不利影响,一般在一周后即开始恢复.小球藻生长几乎不受塔玛亚历山大藻的影响,混合培养水体中的小球藻生长曲线与单种培养的几乎一致,其悬浮性也无明显改变.与亚心形扁藻进行混合培养的塔玛亚历山大藻(ATCI01品系和ATHK品系)均表现出培养前期增殖曲线与单种培养类似,但在一周后混合培养的塔玛亚历山大藻的增殖曲线开始下降,这一时间恰好与扁藻细胞密度开始增加的时间相一致.而与小球藻的混合培养的塔玛亚历山大藻在培养前期与单种培养一致,后期则种群数量有所下降. 相似文献
9.
麻痹性贝毒PSP在紫贻贝体内的累积、转化与排出 总被引：13，自引：2，他引：13
于1998年9月在青岛鲁迅公园附近礁石区采集紫贻贝（Mytilus edulis)，采用实验室培养的方法，初步研究了塔玛亚历山大藻（Alexandrium tamarense,ATHK)产生的麻痹性贝毒（Paralytic Shellfish Poison,PSP)在其体内累积、转化与排出的规律。结果表明，在累积实验阶段，紫贻贝内脏的和肌肉中的PSP毒素含量均随实验时间的延长而逐渐增加，累积实验结束时，平均每只贝体内的PSP毒素含量为13.40nmol，毒性水平为12.24ugSTXEq/100g，紫贻贝内脏中的毒素含量远远高于肌肉，内脏中PSP毒素占贝体内PSP毒素总量的97.5%。在8天的排出实验阶段，贝体内的PSP毒素总量呈下降趋势，实验结束时，PSP毒素共排除了约50%，每天排除率约为9%。 相似文献
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渤海裸甲藻和链状亚历山大藻的麻痹性贝毒毒素分析 总被引：1，自引：0，他引：1
目的:分析渤海裸甲藻(Gymnodinium sp.)和链状亚历山大藻(Alexandrium catenella)的麻痹性贝毒毒素,为渤海天津海域的赤潮研究积累基础数据。方法:通过实验室培养裸甲藻和链状亚历山大藻,选取对数生长期、平台生长期的裸甲藻以及平台生长期的链状亚历山大藻,利用高效液相色谱法(HPLC)对这两种微藻进行麻痹性贝毒(PSP)毒素分析。结果:裸甲藻细胞内不含有麻痹性贝毒(PSP);链状亚历山大藻细胞内含有C毒素和GTX1-4毒素,该微藻每个细胞毒素含量约为10.81 fmol/cell。结论:裸甲藻细胞内虽不含有麻痹性贝毒(PSP),但不能排除其含有其它毒素的可能。链状亚历山大藻细胞内含有麻痹性贝毒(PSP),属于有毒微藻,需要对其进行密切监测。 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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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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《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献
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The relationship between the flux of exotic benthic foraminiferal tests (i.e. tests which are supplied from open-sea sources alone) in a tidal inlet and that of bulk sediment was analysed, which can be expressed as two first-order linear equations. According to this relationship, in order to determine net sediment transport directions in the entrance, the test concentration in surficial sediments of the tidal basin can be compared against a ‘ critical level ’. The critical level is determined for the conditions that no net transport of bulk sediment is present within the entrance. If the observed concentration (averaged over the tidal basin) is higher than the simulated critical level, then the net sediment transport is directed to landward. This method is applied to the analysis of net sand transport at Christchurch Harbour, a tidal inlet system located in southern England. In this investigation, concentrations of exotic foraminiferal tests in the surficial sediments of the tidal basin and ebb tidal delta area were obtained from the analysis of sea-bed sediment samples. A series of probable critical levels were calculated based upon the data sets with regard to: (1) sediment discharge from the rivers; (2) magnitude of sediment discharge within the entrance during the ebb; (3) the test concentration outside the harbour; (4) the thickness of the moving layer; and (5) two parameters associated with dispersive processes. The results show that the concentration in the tidal basin sediment is higher than a number of simulated critical concentrations for representative cases. Consequently, the high level of the concentration of exotic benthic foraminiferal tests within the harbour should be explained as a result of landward net transport of sands within the entrance. 相似文献
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The behaviour of an axially pre-loaded cylindrical member of an offshore structure, hit by a supply ship, has been investigated. The effects of axial pre-loading on the dynamic properties of members, the extent of damage and propagation of dynamic instability in the tubular members have also been investigated. Numerical models have been validated using available experimental data from the literature although these are mostly static with no pre-loading. Axial pre-loading was found to change the dynamic characteristics of some cylindrical members quite dramatically while it had no significant effect on others. The study examined whether there was any change in the behaviour between local and global modes when the loading was dynamic rather than static. The effect of damping on the dynamic instability of axially pre-loaded tubes under lateral dynamic loads was also studied. It was observed that for some geometries the quasi-static response can be used to define the boundary between bounded and unbounded dynamic responses. The main contribution of this study, compared with previous investigations reported in the literature, is that both pre-loading and dynamic effects have been included. 相似文献
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Rahul Sharma 《Marine Georesources & Geotechnology》2000,18(3):237-250
Observations on seafloor features from subbottom profiling and seabed photography data show that the undisturbed and natural conditions before the benthic disturbance undergo a substantial change after operation of the disturber. The effects can be seen in the form of deep trenches and grooves, formed by the action of the sleds and the pumping of the sediment along its path, as well as sediment piles on either side of the track. Biological traces such as fecal coils, casts, tubes, burrows, and trails get obliterated in the areas of disturbance and resedimentation. The smooth, uniform nature of the seafloor observed in predisturbance phase shows microtopographic changes in and around the disturbed area as a result of sediment excavation and resettlement. Vertical mixing as well as lateral transport of sediment alter the geological, biological, physical, and chemical conditions on the seafloor, which need to be monitored over time to assess the process and the time taken for restoration of environmental conditions. 相似文献
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Vance P. Vicente 《Marine Ecology》1989,10(2):179-191
Abstract. Long-term changes in the distributional patterns of commercial sponges ( Spongia spp. and Hippospongia spp.) within the West Indian Region indicates that: 1) commercial sponges had a widespread distribution throughout the whole West Indian Region and were ubiquitous in very shallow water until about the first half of the present century; 2) they were fished commercially not only in the traditional northern Caribbean sites (Florida, Gulf of Mexico, Bahamas) but also in the Greater ( e. g. , Hispaniola, Jamaica) and Lesser Antilles; and 3) they became extinct throughout most of the Lesser Antilles ( e. g. , Puerto Rico, Vieques, St. Thomas) sometime during the first half of this century. Mortalities of spongiids within the Antilles were found to differ from other marine mortalities in that: 1) species disappeared from a large region; 2) species vanished from different habitats and depths; and 3) natural populations never recovered. Species richness patterns suggest that commercial sponge genera ( Spongia and Hippospongia ) evolved under slightly cooler elimatic conditions than those found at present, and that these extinctions occurred as a direct or indirect effect of positive thermal anomalies in sea surface and atmospheric temperatures between 1900–1950. The concept that species diversity is stable on a regional scale is questioned. 相似文献