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1.
甲壳动物化学感觉研究进展   总被引:6,自引:0,他引:6  
本文从甲壳动物化学受体的形态、动物个体的行为反应以及化学感觉神经元的电生理三方面综述了甲壳动物化学感觉研究近20年的进展。水生动物,如甲壳动物特别是底栖甲壳动物,主要依赖化学感受器获得其生存环境的信息,从而表现出摄食、逃避捕食者、觅偶、交配、洄游等各种不同的行为反应。早期的研究主要是直观的行为观察和化学感受器的形态描述,内容偏重于动物的摄食习性和化学感受器的结构及其分布。随后电生理方法和电镜技术的引入,使化学感觉生理学的研究深入到细胞水平,发现了受体细胞的一些特性,如低自发放电频率、低阈值、调制、适应和去适应、范围分级等。另外,还提出了甲壳动物化学受体对化学信号的两种基本编码方式,即单线编码模式和交叉神经元模式。  相似文献   
2.
Deep-sea red crabs Chaceon ramosae and Chaceon notialis are commercially and ecologically important crustaceans in South Atlantic waters. With some overlapping occurring at the edge of the crabs’ distribution, the fisheries are managed separately in Brazil and Uruguay, with some differences in the regulations, although the stock is supposedly shared between the two countries. To assess genetic information on these two species, we examined the nucleotide sequence of the mitochondrial 16S rDNA and CO1 mtDNA genes in samples from the southern region. We also compared these data to sequences from other congeners. The genetic analysis revealed a clear separation between C. notialis and C. ramosae. In addition, we detected the existence of at least two different groups within the species that is currently recognized as C. notialis. This might indicate the existence of cryptic species, leading us to speculate about the presence of two different taxonomic entities, although further research is needed to resolve this issue.  相似文献   
3.
甲壳动物中的酚氧化酶原激活系统研究评价   总被引:56,自引:3,他引:53  
依据80-90年代国际关于甲壳动物免疫机制的资料,对甲壳动物中的酚氧化酶原激活系统的研究进展予以综合评价,目的在于为中国科技工作者防治虾蟹类疾病提供参考。现有的研究表明,甲壳动物中的酚氧化酶原激活系统可被微生物多糖激尖,在激活过程中产生一系列活性物质,通过多种形式参与宿主防御反应。在甲壳动物中,与proPO系统有关的因子正在被逐步纯化出来;proPO可由内源蛋白酶转化成活性形式,存在调节因子调节p  相似文献   
4.
Currently, nanotechnology has gained much interest due to the unique properties of nanomaterials in science and technology. Different types of metallic nanoparticles are routinely synthesized. However, their release into the aquatic environments is a major ecotoxicological concern. In this scenario, it is important to study the potential impact of engineered nanoparticle in aquatic organisms especially freshwater microcrustaceans, such as Ceriodaphnia cornuta. In this study, ZnO NPs were synthesized using the aqueous leaf extracts of Musa paradisiaca and physico-chemically characterized by UV–Vis spectroscopy, X-ray diffraction (XRD), Fourier transform infra red (FTIR), scanning electron microscopy (SEM) and atomic force microscopy (AFM). UV–Vis spectroscopy recorded the absorbance peak of ZnO NPs at 338 nm. XRD analysis showed the various Bragg’s reflection peaks at 100, 002, 101, 102, 110, 103, 200, 112, 201, 004 and 202 lattice planes. FTIR spectroscopy outlined sharp intense peaks at 3416 cm−1, 1388 and 1416 cm−1. SEM showed the spherical shape of ZnO NPs with mean particle size of 23.3 nm. AFM confirmed the spherical shape, nanosize and 3D topography of NPs. The ecotoxicity of ZnO NPs was tested on the freshwater crustacean C. cornuta. ZnO NPs were comparatively less toxic than zinc acetate. ZnO NPs caused 42% mortality of C. cornuta at 50 μg mL−1. However, 80% mortality was observed at 50 μg mL−1 of zinc acetate after 24 h. Light and confocal laser scanning microscopic images evidenced the uptake and accumulation of ZnO NPs in the gut of C. cornuta at 50 μg mL−1 after 24 h. Structural deformities were observed on C. cornuta after treatment with 50 μg mL−1 of ZnO NPs. Overall, this study describes the potential impact of the biologically synthesized ZnO NPs in comparison with zinc acetate in the freshwater crustacean C. cornuta.  相似文献   
5.
Early Cretaceous development of the Mecsek Mts. (South Hungary) is characterized by continental rifting that produced mixed volcano-sedimentary rocks in the Tihonian/Berriasian and built up a volcanic edifice in the earliest Cretaceous of ankaramite-alkaline basalts. During the Valanginian, marl sedimentation occurred in the basinal part containing rich pelagic fauna dominated by ammonites. Beside phylloceratids, lytoceratids and haploceratids, Kilianella roubaudiana, K. lucensis, Sarasinella eucyrta, Thurmanniceras pertransiens, Th. (Clavithurmannia) foraticostata, Busnardoites campylotoxus, Olcostephanus drumensis, O. densicostatus, and Sabbaiceras stefanescui are indicating the Early and Late Valanginian Thurmanniceras pertransiens, Busnardoites campylotoxus and Saynoceras verrucosum zones. The Early Valanginian is also supported by Calpionellites darderi indicating the calpionellid “E” zone. The marl sequence contains a turbidite bed with rich fauna of shallow marine origin from the volcanic slope of lagoonal, reef, and tidal environs, however it contains metasomatized limestone olistoliths of different origin. Source of these olistoliths is the near iron-ore deposit, which is considered an embryonic shallow water hydrothermal vent. It includes a remarkable fauna of rich crustacean coprolite ichnospecies of Favreina dispentochetarius, F. hexaochetarius, F. octoochetarius, Palaxius decaochetarius, P. tetraochetarius, P. triochetarius. In the neighbourhood of the embryonic vent, a remarkable megafauna occurs, which is an almost monospecific brachiopod fauna dominated by Lacunosella hoheneggeri. Other brachiopods as Nucleata veronica, Moutonithyris moutoniana, Karadagithyris sp., and Zittelina pinguicula also occur as stray individuals. Together with benthic megafauna, nektonic elements as Nautiloidea gen. et sp. ind, phylloceratid- and lytoceratid ammonites and echinoid spines of Balanocidaris rysacantha occur.  相似文献   
6.
鱼饲料着色剂-甲壳类下脚料类胡萝卜素的提取技术   总被引:6,自引:0,他引:6  
本文对近40年来甲壳类下脚料中类胡萝卜素的提取技术进行了综述,其提取技术流程主要包括:1.下脚料预处理。下脚料研磨后经2mm筛网去除几丁质残渣,或研磨后直接提取;2.热醋酸、盐酸的直接去钙化或酸青贮(有机酸及无机酸)去钙化;3.添加蛋白酶进行水解;4.类胡萝卜素的油提取及化学提取。三个阶段批逆流加工法及有机溶剂(丙酮、己烷、石油醚)提取类胡萝卜素5.类胡萝卜素稳定性控制。在整个处理工艺的某阶段添加  相似文献   
7.
The new crustacean microcoprolite Sulcusina iberica n. ichnogen., n. ichnosp., is described from the Upper Cretaceous Alarcón Formation (?uppermost Cenomanian to ?lower Coniacian) of the Southern Iberian range. The new ichnogenus is characterized by rod-shaped bodies with parallel-running longitudinal canals (without interconnecting lines) of rounded transverse sections within the symmetry plane. Characteristic is the presence of a central longitudinal furrow (or canal) that extends to the middle of the microcoprolite, without any connection to the laterally grouped canals of usually lower diameter. The latter display a circular outline in transverse sections. Sulcusina n. ichnogen. can be compared to some extant with both Helicerina Brönnimann & Masse and Lercarina Senowbari-Daryan. The new microcoprolite occurs in monotypic grainstones together with some thin-walled miliolids and ostracods ascribed to a peritidal facies.  相似文献   
8.
南京玄武湖浮游甲壳动物的水平分布及其与环境的关系   总被引:1,自引:1,他引:0  
于2010年7月对玄武湖三个区域(荷花区、湖岸区、敞水区)的浮游甲壳动物水平分布进行了分析,并探讨了浮游甲壳动物种类、丰度分布与环境因子的关系.结果显示:荷花区、湖岸区、敞水区的氮磷营养盐浓度无显著差异,三个区域pH逐渐变高.相比其他区域,荷花区叶绿素a浓度最高而总悬浮质浓度最低.荷花区浮游甲壳动物丰度显著高于敞水区和湖岸区.全湖枝角类优势种为模糊秀体溞、微型裸腹溞、尖额溞以及壳纹船卵溞.桡足类的优势种为北碚中剑水蚤和台湾温剑水蚤.与其他湖区相比,荷花区浮游甲壳动物种类最多,且检出缺刺新秀体溞等稀有枝角类.冗余分析(RDA)表明与玄武湖浮游甲壳动物优势种分布相关的重要环境因子为总悬浮质、叶绿素a和总溶解磷浓度.结合浮游甲壳动物种类、丰度分布及环境因子分析得出,模糊秀体溞更倾向于分布在敞水区,而荷花区为其余大部分浮游甲壳动物种类提供了合适的生存条件.  相似文献   
9.
采用RT-PCR及RACE技术,从拟穴青蟹眼柄组织中克隆了两种Ⅰ型高血糖激素CHH基因(分别命名为C1与C2)cDNA全序列。序列分析结果表明:C1基因全长1859bp,开放阅读框长420bp,编码139个氨基酸,分子量为15.326kDa,等电点为5.540;C2基因全长1739bp,开放阅读框长426bp,编码141个氨基酸,分子量为15.621kDa,等电点为7.618。与其它物种CHH氨基酸序列进行同源性比较分析显示,拟穴青蟹CHH基因与榄绿青蟹CHH基因同源性最高(92%),依次为日本鲟(80%)、三疣梭子蟹(78%)。聚类分析表明,拟穴青蟹CHH氨基酸序列与榄绿青蟹和日本鲟紧密聚为一支。经荧光定量检测,拟穴青蟹CHH基因在眼柄、肝胰腺、心脏、肠中表达量较高,鳃、胃中表达量很少,肌肉中表达极少。盐度骤变试验结果表明:盐度胁迫24h后,C2的表达量是C1的30倍以上;C2基因盐度5时与对照组的表达量差异不显著(P>0.05),盐度15时差异显著(P<0.05),盐度22、25、30时差异极显著(P<0.01);盐度变化越大,C2的表达量越大。上述结果为进一步深入研究CHH基因的功能及调控机理奠定基础。  相似文献   
10.
This is the first study describing the crustacean fauna associated to Asparagopsis armata, a non-native, red seaweed widely distributed along western Mediterranean coasts. First found in Australia and New Zealand, it was introduced naturally through the Strait of Gibraltar and rapidly spread out. A one-year spatio-temporal study (Feb 08-Feb 09) was carried out in the Strait of Gibraltar to characterize the spatio-temporal patterns of the associated crustacean fauna. Maximum biomass of A. armata was measured during April-June, whereas the maximum crustacean abundances were registered from June-October. In total 41 crustacean species were identified. The caprellid Caprella penantis, traditionally associated to non-polluted areas, was more abundant on Tarifa Island (higher values of dissolved oxygen and pH) than in Algeciras (lower oxygen and pH). The gammarid Podocerus variegatus was dominant in Algeciras Bay while Hyale schmidti and Apherusa mediterranea were the most abundant on Tarifa Island. Among isopods, Synisoma nadejda was only found on Tarifa Island. When compared with literature of native algae of the intertidal and shallow sublittoral, the species richness of associated crustaceans was similar in A. armata and the natives. Very little is known about the influence of this algae on altering marine communities, so complete faunistic studies dealing with other groups such as polychaetes or molluscs are necessary to properly address biogeographical, ecological and management programmes dealing with this non-native species.  相似文献   
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