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1.
利用血凝试验及糖抑制试验测定脊条褶虾蛄的血清及肌肉提取液的凝血活性及糖抑制专一性，同时进行热稳定性、pH及Ca^2 影响试验。结果显示：其血清能凝集12种红细胞，且其凝集效价高于肌肉提取液（兔、蛇、鲫鱼除外）。血清对鹌鹑红细胞的凝集可被D－果糖、D－半乳糖和蔗糖所抑制，最小抑制浓度均为200mmol/dm^3，其凝集活性均依赖于Ca^2 ，在pH值为5.0-9.0范围内较稳定，经40℃保温10min后活性完全消失；肌肉提取液不被7种糖抑制，在pH值为4.0-10.0、温度为40－90℃范围内均具活性，说明有很强的耐热性，其凝集性不依赖于Ca^2 。以上结果表明：脊条褶虾蛄血清与肌肉提取液均含有凝集素，且凝集素的种类不同。 相似文献
2.
毛蚶血清凝集素的凝集活性 总被引：2，自引：1，他引：2
以毛蚶为实验材料,对其血清中的凝集素进行研究.毛蚶血清凝集素对人的A,B,O血型红细胞、鸡和小鼠的红细胞均有凝集作用,凝集效价分别为256,256,8,16,64,同时它还能对白色念珠菌、啤酒酵母、溶藻胶弧菌等微生物具有凝集作用.毛蚶血清凝集素具有一定的pH值稳定性和热稳定性.在选用的12种单糖和寡糖中,L-鼠李糖、L-树胶醛糖、麦芽糖、D-半乳糖、蔗糖对毛蚶血清的凝集活性有明显的抑制作用.用弧菌对毛蚶进行免疫刺激时,其血清对鸡红细胞的凝集效价明显增加. 相似文献
3.
甲壳动物血清中凝集素对微生物细胞的凝集性能 总被引：7，自引：1，他引：7
用12种甲壳动物血清凝集素提取液，对10种微生物细胞进行凝集试验，发现每种甲壳动物血清至少能凝集3种微生物细胞，酿酒酵母(Saccharomyces cerevisiae)细胞对凝集素反应最为敏感。7种甲壳动物血清凝集素对酿酒酵母细胞的凝集可被2种以上的糖所抑制，12种甲壳动物血清凝集素的温度和pH适应范围表现不一，但它们的凝集活性都被EDTA所抑制。 相似文献
4.
草鱼血清中一种新的凝集素免疫因子 总被引：2，自引：0，他引：2
于1998年5月－2000年3月，在浙江省杭州市采集草鱼，采用硫酸铵盐析和梯度聚丙烯酰胺凝胶电泳技术，从血清中分离出一种自然凝集素，对其理化和生物学性质进行研究。结果表明，该凝集素能够识别和凝集多种不同的红细胞、细菌和酵母，具有100000g离心不沉降，不被透析，耐热、耐酸、耐碱，抗DNase、RNase、SDS和乙醚，对胰蛋白酶、糖苷酶、糖氧化剂NaIO4和β－巯基乙醇敏感等特性，是一种分子量为67kD、等电点为6．2的糖蛋白分子。其活性能被半乳糖、乳糖、甘露糖和N－乙酰葡糖胺所抑制，其抗原特异性不同于草鱼凝集集抗IgM，表明两者是不同的物质。草鱼凝集素显著地促进巨噬细胞的吞噬、杀菌能力，说明是一种重要的免疫活性因子。 相似文献
5.
斑纹鲟凝集素(CFL)的初步研究 Ⅱ.CFL的分子组成及性质鉴定 总被引：3，自引：0，他引：3
采用生化方法对斑纹鲟(Charybdis feriatus)凝集素进行了初步研究.结果表明,斑纹鲟的血清中有动物红细胞和微生物细胞凝集活性的凝集素(Charybdis feriatuslectin,CFL),其活力表现依赖于Ca2+,并为多种糖所抑制;CFL对40℃以上的温度敏感,其活力在pH6.0~8.0内稳定.经巯基乙醇处理和未经巯基乙醇处理的CFL在SDS-PAGE上均为一条蛋白带,说明斑纹鲟凝集素不含二硫键,且只有一种亚基,分子量为40.8 kDa,CFL氨基酸组成分析表明其富含酸性氨基酸. 相似文献
6.
凡纳滨对虾血清凝集素、溶血素的特性研究 总被引：3，自引：0，他引：3
对凡纳滨对虾(Litopenaeus vannamei)的血清凝集素和溶血素部分特性的研究结果表明,凡纳滨对虾血清凝集素热稳定性较差,温度高于50℃时,活性呈明显减弱至无活性,其最适温度为25~45℃;最适pH为8~9;盐度为24~48时,凝集活性最强,当盐度超过48或者低于6时,凝集活性较差;凝集素活性能被浓度高于16 mmol/L(包括16 mmol/L)EDTA-Na2,D-葡萄糖,D-果糖及D-半乳糖完全抑制。Cu2 使凝集素的活性完全丧失,而Ca2 和Mg2 能使凝集活性明显增强。45~60℃时,溶血素活性逐渐增强,60℃时达到最高;当pH 6~9时,溶血素的活性较强;盐度为18~36时,能增强溶血素的活性;EDTA-Na2对溶血素的活性几乎无影响;Cu2 使溶血素丧失活性,Mg2 能增强溶血活性,Mn2 对溶血素的活性没有影响,而Ca2 和Ba2 对溶血素有轻微的抑制作用。 相似文献
7.
双壳贝类血清中凝集素凝集性能初步研究——对脊椎动物血细胞的凝集作用 总被引：6，自引：0，他引：6
在多种贝类血清中发现有可凝集脊椎动物血细胞的因子——凝集素。栉孔扇贝（Ｃｈｌａｍｙｓｆａｒｅｒｉ）血清中的凝集素可凝集鸡、鹌鹑、小鼠等多种动物血细胞,但对鳝鱼血细胞不发生作用。该凝集素具有较强的热稳定性,１００℃处理４５ｍｉｎ仍具活性;并具有广泛的ｐＨ范围,可在ｐＨ３～１１进行凝集作用。但其活性可被ＥＤＴＡ强烈抑制,Ｄ－甘露糖和Ｌ－鼠李糖对其活性有明显抑制作用,Ｄ－木糖和蕈糖也有轻微抑制作用。在栉孔扇贝血细胞的细胞膜上未发现有凝集鸡血细胞的活性物质。另外,用大肠杆菌和副溶血弧菌刺激栉孔扇贝后,血清的凝集作用不变。 相似文献
8.
本研究利用阳离子交换和分子筛的方法成功分离鉴定出分子量为105kDa，以多聚体形式存在七鳃鳗凝集素。实验结果表明，首先运用阳离子交换色谱方法能够将七鳃鳗血清混合组分进行初步分离，结合凝集活性鉴定方法，鉴定凝集活性最强组分存在于第二峰中。其次；利用分子筛方法将具有凝集活性组分进一步分离，最终得到分子量为105kDa左右具有凝集活性组分。结合Native-PAGE和SDS-PAGE结果表明，凝集活性组分以三聚体形式存在。同时，飞行时间质谱方法鉴定结果为凝集素（gi:13094239）。最终，体外鉴定结果表明七鳃鳗凝集素对兔红细胞和山羊红细胞均具有较强的凝集活性。七鳃鳗凝集素的分离纯化对研究七鳃鳗先天免疫防御机制和可变淋巴受体介导的适应性免疫防御机制均具有重要意义。 相似文献
9.
C型凝集素是一类依赖于钙离子的糖识别蛋白超家族,该家族蛋白在海洋无脊椎动物先天免疫系统中的非己识别和对病原微生物的清除过程中起重要作用。本文以三疣梭子蟹(Portunus trituberculatus)含单个糖识别域(CRD)的C型凝集素PtCTL-6为研究对象展开研究。研究表明PtCTL-6的开放阅读框(ORF)编码一条由信号肽、LDLa和CRD组成的多肽链。该C型凝集素的识别关键基序为DPY/WTD(Asp-Pro-Tyr/Trp-Thr-Asp),未见于前人研究。病原相关分子模式(PAMPs)结合活性检测结果表明:PtCTL-6重组蛋白(rPtCTL-6)能结合脂多糖(LPS)、肽聚糖(PGN)和β-葡聚糖(β-glucan),并能结合7种微生物,包括革兰氏阴性菌、革兰氏阳性菌和真菌。凝菌活性实验证明, PtCTL-6能选择性地凝集真菌毕赤酵母(Pichiapastoris)与酿酒酵母(Saccharomycescerevisiae)。以上结果证实PtCTL-6能作为模式识别受体参与机体对微生物的识别,并且该分子具备较广泛的免疫识别谱。最后,本文初步探索了该分子对"非己"物质的识别机制,发现PtCTL-6通过特异性的结合D-甘露糖和D-岩藻糖对"非己"物质进行识别,是一种具备新型糖结合模式的C型凝集素。 相似文献
10.
温度、pH对日本沼虾血清酚氧化酶活力及稳定性的影响 总被引：9，自引：0，他引：9
以日本沼虾（Macrobrachium mipponense)为材料，研究温度，pH对其血清酚氧化酶活力及稳定性的影响。试验以L－多巴为作用底物，测得酚氧化酶的最适温度为40℃，大于或低于该值，酶活力均迅速下降，同时该酶在40℃以下表现出较高的热稳定性；该酶的最适pH值为7．0；在pH6－8范围内具有较高的活性，最稳定的pH为8．0。 相似文献
11.
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
12.
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
13.
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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15.
《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
16.
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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18.
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
19.
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
20.
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