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1.
中国对虾一种C型杆状病毒随机扩增多态性DNA分析   总被引:13,自引:1,他引:13  
于1994年和1995两年的7月从青岛崂山上马镇养虾场中染病的中国地虾中分离纯化出一种C型杆状病毒。为建立中国对虾病毒的鉴别和检测技术,利用随机扩增多态性DNA技术对电泳纯化的病毒DNA进行分析和研究。将病虾匀浆、经差速离心和蔗糖密度梯度离心纯化获得完整病毒粒子;从病毒中提取DNA后再进行电泳纯化,收集长度完整,均一的病毒DNA:在其他参数保持不变的情况下,对Operon生产的10碱基随机引物K试  相似文献   

2.
于1991年9月在青岛市沙子口镇对虾养殖场采集中国对虾病虾,采用酒石酸钾-甘油密度梯度离心法从病虾肝胰腺中分离出一种呼肠孤科病毒,并通过电子显微镜观察和提取分析病毒基因组核酸等方法初步鉴定,结果显示,该病毒在酒石酸钾-甘油密度梯度离心纯化时与肝胰腺细小病毒混合存在,病毒颗粒为有包膜的正二十面体立体对称结构;带包膜的完整颗粒直径在64-66nm;裸露核衣壳平均直径为53.2nm,病毒基因组由分成10  相似文献   

3.
中国对虾肝胰腺细小病毒的纯化与鉴定   总被引:4,自引:0,他引:4  
于1991年9月-1993年底,利用在青岛市沙子口对虾养殖场采采的中国对虾病虾肝胰腺样品,采用一种改进的酒石酸钾-甘油密度梯度离心法,对原先称之为肝胰腺细小样病毒的一种对虾病毒进行纯化。通过电子显微镜观察,提取病毒核酸用不同核酸酶处理并结合电泳等方法,对病毒的基本生物物理和生物化学特性作鉴定,结果表明,用酒石酸钾-甘油密度梯度离心法,可获得良好的病毒纯化效果;纯化后的病毒颗粒显示正二十面体立体对称  相似文献   

4.
1993年11月 ̄1994年1月用简单的羟基磷灰石柱层析法从多管藻中分离纯化了R-藻红蛋白和从钝顶螺旋藻中纯化了C-藻蓝蛋白,它们的纯度(指可见光部分的最大吸收与280nm处吸收值之比)可分别达到6(R-藻红蛋白)和5.5(C-藻蓝蛋白)。由于不同藻种的同种藻胆蛋白的摩尔消光系数不同,所以应用凯氏定氮法并结合可见光的吸收值测定了上述两种藻胆蛋白的摩尔消光系数,钝顶螺旋藻C-藻蓝蛋白为1.853×1  相似文献   

5.
1993年11月~1994年1月用简单的羟基磷灰石柱层析法从多管藻中分 离纯化了R-藻红蛋白和从钝顶螺旋藻中纯化了C-藻蓝蛋白,它们的纯度(指可见 光部分的最大吸收与 280nm处吸收值之比)可分别达到 6(R-藻红蛋白)和 5. 5(C- 藻蓝蛋白)。由于不同藻种的同种藻胆蛋白的摩尔消光系数不同,所以应用凯氏定 氮法并结合可见光的吸收值测定了上述两种藻胆蛋白的摩尔消光系数,钝顶螺旋 藻C-藻蓝蛋白为1.853 × 106mol-1cm-1(620nm),多管藻R-藻红蛋白为1.796 × 106mol-1cm-1(498nm),为藻胆蛋白的浓度测定提供了方便。  相似文献   

6.
氨氮对中国对虾抗病力的影响   总被引:91,自引:3,他引:91  
1996年5月24日-6月14日,8月1-19日,分别在青岛的两个养殖场采集海捕产卵后中国对虾亲虾和养殖中国对虾,采用人工添加氨氮并检测对虾和抗菌有关因子的活力的方法,进行氨氮对中国对虾抗病力影响的实验。结果表明,在氨氮浓度较高的实验组,对虾血细胞数目减少,其结构也有变化;酚氧化酶,超氧化物歧化酶和过氧化物酶活力,以及溶菌和抗菌活力都较对照组有明显下降;对病原菌的易感性明显提高。  相似文献   

7.
作者从发生白点综合征的中国对虾中,提取了一株白点综合征病毒,用电镜对纯化的病毒进行了形态学观察,并对病毒纯化过程中蛋白酶抑制剂的使用及离心速度的选择进行了探讨。经蔗糖密度梯度离心,分取各带负染后电镜观察,病毒条带位于40%~50%蔗糖梯度之间,其完整毒粒长225~270nm,直径75~88nm,有的完整毒粒带有很长的尾,病毒衣壳长250~320nm,直径60~80nm。在匀浆使用的缓冲液中加入蛋白酶抑制剂PMSF,可得到完整的带包膜的病毒颗粒,比不使用PMSF的提纯效果要好。经3000r/min离心5min,5000r/min离心25min,去除大部分的组织碎片,经10000r/min离心1h,可使大部分病毒沉淀。并采用传统的方法对病毒核酸进行了提取,其基因组经初步分析为dsDNA。  相似文献   

8.
绿色巴夫藻硒多糖的提取、分离与纯化   总被引:12,自引:5,他引:7  
于1995年3-7月采用本实验室培养的绿色巴夫藻,经沸水提取及去除蛋白,小分子物等杂质后,通过SephadexG-50柱层进行分离,纯化实验。结果表明,分离纯化得到的两种多糖-4P1和4P2,通过醋酸纤维素薄膜电脉及SephadexG-100凝胶过滤检验纯度后,证实其均为单一含硒多糖,且都带负电。两种硒多糖含硒量都较低,分别为77mg/g和220mg/g。  相似文献   

9.
用逆转录聚合酶链反应检测草鱼出血病病毒的研究   总被引:3,自引:1,他引:3  
王铁辉  李军 《海洋与湖沼》1997,28(1):1-6,T001
于1994年5月-1995年7月,根据已克隆的草鱼出现血病病毒GCHV-861株cDNA的部分序列,设计合成了两对PCR引物,采用RT-PCR技术对GCHV-861GCHV-873两病毒株的dsRNA进行扩增,结果表明,两对引物仅能特异地检测了GCHV-861病毒株核素的存在,而不能对GCHV-873病毒株的核酸进行特异扩增,该方法是最小可检测出0.1pg纯化的GCHV-861病毒dsRNA,采用  相似文献   

10.
中药制剂对中国对虾免疫活性物的诱导作用   总被引:60,自引:0,他引:60  
罗日祥 《海洋与湖沼》1997,28(6):573-578
分别于1994年和1995年9-10月以胶州湾海捕中国对虾为材料,取其血淋巴测定血凝素活力,溶菌活力,并以投喂添加VC,VB6,中药制剂1号,中药制剂2号的药饵17d,25d后的免疫性的活力动态变化,  相似文献   

11.
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   

12.
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   

13.
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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16.
A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria ( 〉 99% ), but also between polar marine bacteria and bacteria from other aquatic environments ( ≥ 98.8% ), including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.  相似文献   

17.
Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations.  相似文献   

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19.
《海洋学报(英文版)》2014,(8):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   

20.
This article presents a methodology developed to evaluate the instability of submarine slopes that extend over a large area. Special attention was paid to (1) the complex geometry (bathymetry) and the expanse of the slope, (2) the heterogeneity of the sediment, and (3) the distribution of the pore pressure. The safety factor was considered as a spatially varying quantity. The General Formulation (GLE, Fredlund and Krahn 1977), which fully satisfies equilibrium conditions, was used for evaluating the stability of the marine slope. The submarine slope failure, which occurred on 16 October 1979 during the construction of the new Nice airport, was studied in order to test the developed model. Geotechnical parameters were taken from experimental tests carried out by IFREMER on 19 cores extracted at different depths (from 27 m to 1300 m) (Cochonat, Bourillet, and Savoye, 1993; Mulder et al., 1994). Many scenarios were proposed in order to explain the cause of the Nice slope failure (Habib, 1994). In this article, two of those scenarios were tested. Simulation results are presented and discussed.  相似文献   

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