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91.
本实验针对两次突发的饲养海月水母(Aureliaaurita)大规模烂洞解体状况,通过对病灶处进行细菌培养,从其中每次发病水母中均各分离到2种优势病原菌菌株,利用PCR扩增和DNA测序技术,获得优势菌株16SrRNA基因序列,通过生物信息比对分析显示,导致两次海月水母发病的病原菌菌株分别为2种嗜冷杆菌(Psychrobacter sp.)和2种弧菌(Vibrio splendidusVibrio neptunius)。通过利用福林酚法进行此四种优势菌株的细菌发酵培养液蛋白酶活性的测定,结果显示,此4种细菌均具有较强的蛋白酶活性。根据实验结果推测,分离所得的2种嗜冷杆菌菌株(Paa1Paa2)和2种弧菌菌株(Vaa1Vaa2)作为此次发病海月水母的病原菌,有可能均是通过分泌胞外蛋白酶侵蚀水母伞体,从而导致伞体烂洞解体。通过本次实验分析,推测自然条件下水母暴发后的快速消亡是由水母自身免疫下降与细菌侵染的共同作用导致。 相似文献
92.
通过野外海区挂板的方法,探讨高密度聚乙烯(HDPE)、低密度聚乙烯(LDPE)、聚氯乙烯(PVC)、聚苯乙烯(PS)、聚对苯二甲酸乙二酯(PET)和聚氨酯(PUR)6种不同材料的塑料挂板对海月水母(Aurelia sp.1)附着的影响,分析不同塑料挂板表面粗糙度和海月水母附着的关系.研究结果表明:海月水母浮浪幼虫在夏末秋初可以附着在人工投放的塑料挂板附着基上,表明海岸带工程造成的人工附着基增多可能为海月水母的附着提供便利条件;海月水母螅状幼体在不同材料塑料挂板上的附着率有明显差异,PET、PUR和PVC塑料挂板海月水母螅状幼体附着率显著大于其他3种塑料挂板,其中PUR塑料挂板海月水母螅状幼体附着率最大,附着率为3.21±0.74 ind./cm2,HDPE塑料挂板海月水母螅状幼体附着率最低为0.26±0.08 ind./cm2;海月水母浮浪幼虫附着率与不同材料表面的粗糙度并不显著相关,表明塑料挂板材料的表面粗糙度并不是影响海月水母螅状幼体附着率的关键因子,而不同材料塑料挂板上形成的生物膜可能也对海月水母浮浪幼虫的附着产生影响.研究结果可为我国近岸海域有害水母海月水母暴发和防控研究提供一定的重要参考数据. 相似文献
93.
黄渤海沿岸海参养殖池为海月水母(Aurelia aurita)幼体的重要栖息地,海参养殖池盐度波动范围极大,因此,研究不同盐度对海月水母早期生活史的影响对于理解其环境适应机制具有重要科学意义.本研究以海月水母为研究对象,探讨了不同盐度梯度(18、22、26、30、34和38)对海月水母浮浪幼虫行为、附着以及螅状幼体无性生殖的影响.结果表明,盐度对海月水母浮浪幼虫的运动行为存在显著影响,较高盐度环境(30、34和38)海月水母浮浪幼虫运动速度明显高于较低盐度环境(18、22和26);盐度对海月水母浮浪幼虫的附着有显著影响,相对较高盐度促进海月水母浮浪幼虫的附着,盐度为34时,海月水母浮浪幼虫附着率最高;海月水母螅状幼体无性生殖能适应较广的盐度范围,42d无性生殖实验周期后,18~34盐度环境下海月水母每个螅状幼体平均新繁殖螅状幼体个体数为2.8~3.7个,不同盐度处理组间无显著差异,而极高盐度(38)显著降低海月水母的出芽生殖率(1.2个).本研究表明盐度对海月水母早期生活史不同阶段幼体具有不同影响,研究结果为黄渤海沿岸海月水母环境适应机制研究提供了重要参考. 相似文献
94.
95.
The morphology of seven specimens of Chrysaora chinensis (Scyphomedusae, Semaestomae) obtained from four sites off the coast of Peninsular Malaysia was examined. Morphological characteristics of C. chinensis that encompasses structures such as the bell, tentacles, oral arms, stomach, manubrium, radial canals and gonads were described in detail. A total of 107 specimens that represented C. chinensis populations of four coastal areas of Peninsular Malaysia (East-Central, East-North, West-Central, and West-North) were also analysed for shape variation using geometric morphometric analysis. Procrustes superimposition, Principal Component Analysis (PCA) and Canonical Variate Analysis (CVA) were applied to the images of gastrovascular pouches of C. chinensis to extract the shape information. Independent contrasts were used for comparisons between shapes. There were no significant differences in shape variation between all the specimens based on the PCA results. However, CVA results showed shape variations between specimens taken from the four areas of Peninsular Malaysia, especially with higher magnitudes of Mahalanobis distances between the east and west coast areas, including between East-Central and East-North, but lower magnitudes were detected between the West-Central and West-North. 相似文献
96.
The present work is the first report of the biochemical characterization of the venom from nematocysts of the jellyfish Rhopilema esculentum Kishinouye. The nematocysts were isolated by autolysis and centrifugation and separated by flow cytometry. Four types of
nematocysts were identified: mastigophores, euryteles, and atrichous and holotrichous isorhiza. SDS-PAGE and amino acid analyses
demonstrated that most of the proteins in the nematocyst extract were between 10 kDa and 40 kDa, and that glutamic acid was
the main amino acid. A hemolytic activity assay showed that the activity of the nematocyst venom (RNV) was strongest in Tris-HCl
buffer (50 mmol/L, pH 7.8, 5% glycerol, 0.5 mmol/L EDTA, 0.1 mol/L NaCl). The hemolytic activity was related to protein concentration
and the HU50 against chicken erythrocytes was 0.91 μg/mL. 相似文献
97.
Huan-huan Yang Qin Wang Yan-bo Li Bin Lin Yang Song Yi-yun Wang Wen He Hong-wei Li She Li Jian-li Li Chang-cheng Liu Shi-bin Feng Tang Xin Xue-lian Fu Xin-juan Liang Qi Zhang Bei-qi Wang Yang Li 《China Geology》2022,5(1):136-159
The Tiegelongnan Cu(Au,Ag)deposit in central Tibet contains more than 10 Mt of copper ranking 29 th in the world.It is characterized by typical porphyry-epithermal alteration and mineralization.In order to improve the understanding of porphyry-epithermal copper deposit in Tibet,new zircon U-Pb age and sulfur isotope data along with published data in the Tiegelongnan are presented to investigate the formation and preservation mechanism.Ore-related intrusive rocks in the Tiegelongnan including Early Cretaceous(about 120 Ma)granodiorite porphyry and diorite porphyry are closely related to the northward subduction of Bangongco-Nujiang ocean.Sulfur mainly comes from deep magma,and ore-forming fluid is affected by both magmatic and meteoric water.The metallogenic setting of Tiegelongnan is consistent with those of Andean porphyry copper deposits in South America.The cover of the Meiriqiecuo Formation volcanic rocks,Lhasa-Qiangtang collision and India-Eurasian collision have significance in the preservation and uplift of the deposit.The formation,preservation and discovery of Tiegelongnan play an important role in exploration of ancient porphyry-epithermal deposits in Tibet. 相似文献
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