排序方式： 共有16条查询结果，搜索用时 31 毫秒
1.
物源问题一度成为制约歧口凹陷歧南低斜坡沙三段油气勘探的焦点。在综合分析沉积期古地貌及沟谷展布特征、地震属性特征、碎屑颗粒组分、重矿物组合特征、砂体展布特征等资料基础上,探讨歧南低斜坡沙三段沉积时期物源体系特征及分布。结果表明:歧南低斜坡沙三段存在3大物源体系,其中,西部歧南水道物源体系延伸距离远,波及范围大,控制了歧南低斜坡沙三段沉积时期砂体的形成与分布。进一步研究表明,古物源与沉积体系具良好的空间配置关系。受歧南水道主物源体系控制,低斜坡发育辫状河三角洲前缘沉积,砂体分布具"埕宁隆起物源供砂,歧南水道沟槽输砂,物源体系-坡折带联合控砂"的内在机制。物源方向的确定对研究沉积体系展布、砂体分布及有利勘探区预测具重要意义。 相似文献
2.
Journal of Oceanology and Limnology - Little is known about the roles of dynorphin and Kappa opioid receptor (KOR) in mollusks. In this study, we aim to determine the distribution of dynorphin A... 相似文献
3.
The effects of Bacillus subtilis 2-1 from the intestine of healthy sea cucumber on the growth, digestive enzyme activities and intestinal microbiota of juvenile sea cucumber (Apostichopus japonicus) were determined in the present study. Sea cucumber was fed with Sargassum thunbergii powder supplemented with B. subtilis 2-1 at different concentrations varying among 0 (control), 105, 107, and 109 CFU g?1 for 8 weeks. Results showed that the growth performance and intestinal amylase and trypsin activities were significantly increased by dietary B. subtilis 2-1 at 109 CFU g?1 (P < 0.05). However, dietary B. subtilis 2-1 had no significant influence on the lipase activity in sea cucumber (P > 0.05). The polymerase chain reaction denaturing gradient gel electrophoresis and 16S rRNA gene sequencing analysis indicated that dietary B. subtilis 2-1 at 105 and 107 CFU g?1 inhibited most of the Proteobacteria including those in genus Vibrio. Dietary B. subtilis 2-1 at 109 CFU g?1 not only decreased the abundance and species of genus Vibrio, but also increased the intensity of genera Psychrobacter and Bacillus. A specific dosage of dietary B. subtilis 2-1 could increase the growth and modulate the intestinal microbiota of sea cucumber; thus it might be a novel probiotic for keeping the health of sea cucumber. 相似文献
4.
With the development of aquaculture, there is an urgent demand for an alternative antibacterial agent to reduce the drug resistance and environmental pollution caused by the abuse of antibiotics. Recently, silver nanoparticles(Ag NPs) have been viewed as a novel type of antimicrobial agents due to their unique advantages. In this study,Ag NPs were biosynthesized with the ginger rhizomes extract. The biosynthesized Ag NPs were characterised by UV–visible spectroscopy, transmission electron microscopy, X-ray diffraction and fourier transform infrared spectroscopy. Furthermore, the antimicrobial activities of the Ag NPs were fully analyzed against six typical aquatic pathogens. The results indicated that the components in ginger extract could function as the chemical reductant to synthesize Ag NPs. Moreover, compared with the Ag NPs synthesized by chemical methods, the biosynthesized Ag NPs were smaller, and had higher stability and antibacterial activity. Therefore, the biosynthesized Ag NPs using ginger extract may have prospective applications in aquaculture. 相似文献
5.
We investigated the distribution of four enzymes involved in the immune response of Apostichopus japonicus. We collected samples of the tentacles, papillate podium, integument, respiratory tree, and digestive tract and stained them for acid phosphatase (ACP), alkaline phosphatase (AKP), non-specific esterase (NSE) and peroxidase (POD) activity. The distribution and content of ACP, AKP, NSE, and POD differed among the tissues. The coelomic epithelium of the tentacle, papillate podium, and integument and the mucous layer of respiratory tree were positive for ACP activity. The coelomic epithelium and cuticular layer of the tentacle, papillate podium, and integument and the mucous layer and tunica externa of the respiratory tree and digestive tract stained positive or weakly positive for AKP activity. Almost all the epithelial tissues stained positive, strongly positive, or very strongly positive for NSE activity. The cuticular layer of the tentacle and integument and the mucous layer, tunica submucosa, and tunica externa of the respiratory tree and digestive tract stained positive for POD activity. We hypothesize that these enzymes play a role in the immune response in A. japonicus. 相似文献
6.
断陷湖盆深水重力流水道的识别标志及沉积模式——以歧口凹陷歧南斜坡沙一段为例 总被引：1，自引：0，他引：1
以歧口凹陷歧南斜坡沙一段的深水厚层砂岩为研究对象,运用地震沉积学基本理论和方法,通过古地貌分析约束物源方向,结合岩心观测描述确定沉积相类型,应用地层切片、反演与三维可视化技术确定空间形态。结果表明:该区广泛发育的深水厚层砂岩为重力流水道沉积,包括滑塌岩、砂质碎屑流砂体与浊积岩3种类型重力流沉积的组合;顺北东向展布的断槽内呈大型条带状展布,可划分为水道中心微相、水道边缘微相和水下漫溢微相;岩心中可识别出7种岩相类型。在沉积特征分析的基础上,建立了发育于斜坡且由顺源断层控制的重力流沉积模式,分析了歧南斜坡重力流水道的成因及其油气成藏特征。研究认为重力流水道是该区一类重要的储集体,具有良好的成藏条件,该成果扩大了歧口凹陷油气勘探领域。 相似文献
7.
In this study,a cytochemical method and transmission electron microscopy was used to examine acid phosphatase activities of yolk granules throughout the early developmental stages of the Pacific oyster Crassostrea gigas. This study aimed to investigate the dynamic change of yolk granule acid phosphatase,and the mechanisms underlying its involvement in yolk degradation during the early developmental stages of molluscs. Three types of yolk granules(YGI,YGII,and YGIII) that differed in electron density and acid phosphatase reaction were identified in early cleavage,morula,blastula,gastrula,trochophore,and veliger stages. The morphological heterogeneities of the yolk granules were related to acid phosphatase activity and degrees of yolk degradation,indicating the association of acid phosphatase with yolk degradation in embryos and larvae of molluscs. Fusion of yolk granules was observed during embryogenesis and larval development of C. gigas. The fusion of YGI(free of acid phosphatase reaction) with YGII(rich in acid phosphatase reaction) could be the way by which yolk degradation is triggered. 相似文献
8.
取人工养殖栉孔扇贝(Chlamys farreri)的血淋巴,体外加入不同浓度的硒化壳聚糖,作用1h后采用生化方法分别测定栉孔扇贝血细胞中的髓性过氧化物酶(MPO)和非特异性酯酶(NSE)的活力,以及过氧化氢(H2O2)和活性氧的含量。结果表明:加入硒化壳聚糖后,栉孔扇贝血细胞中依赖卤素的MPO、不依赖卤素的MPO、α-醋酸萘酯酶和α-丁酸萘酯酶的活力均为实验组显著高于对照组,过氧化氢和活性氧的含量也为实验组显著高于对照组。说明硒化壳聚糖对栉孔扇贝血淋巴中多种参与免疫防御的酶的活力和具有杀菌作用的免疫因子的含量均具有明显的提高作用,因而硒化壳聚糖对栉孔扇贝的免疫功能具有明显的增强作用。 相似文献
9.
The effects of Bacillus subtilis 2-1 from the intestine of healthy sea cucumber on the growth, digestive enzyme activities and intestinal microbiota of juvenile sea cucumber(Apostichopus japonicus) were determined in the present study. Sea cucumber was fed with Sargassum thunbergii powder supplemented with B. subtilis 2-1 at different concentrations varying among 0(control), 10~5, 10~7, and 10~9 CFU g~(-1) for 8 weeks. Results showed that the growth performance and intestinal amylase and trypsin activities were significantly increased by dietary B. subtilis 2-1 at 10~9 CFU g~(-1)(P 0.05). However, dietary B. subtilis 2-1 had no significant influence on the lipase activity in sea cucumber(P 0.05). The polymerase chain reaction denaturing gradient gel electrophoresis and 16S rRNA gene sequencing analysis indicated that dietary B. subtilis 2-1 at 105 and 107 CFU g~(-1) inhibited most of the Proteobacteria including those in genus Vibrio. Dietary B. subtilis 2-1 at 10~9 CFU g~(-1) not only decreased the abundance and species of genus Vibrio, but also increased the intensity of genera Psychrobacter and Bacillus. A specific dosage of dietary B. subtilis 2-1 could increase the growth and modulate the intestinal microbiota of sea cucumber; thus it might be a novel probiotic for keeping the health of sea cucumber. 相似文献
10.
芝罘湾长竹蛏肥满度的研究 总被引：5，自引：0，他引：5
本文以１９９０－１９９３年烟台芝罘湾自然生长的长竹蛏为材料，对其肥满度进行了研究。研究结果表明：长竹蛏一年有一个肥满期，一个消瘦期。５月至１１月较肥，肥满指数（１）为５７．３－９３．７。１２月至翌年４月较瘦，肥满指数（１）为４７．２－５６．６。二龄蛏肥满度最高。由肥满指数推断，长竹蛏一年有一个繁殖期，为６月中旬至８月中旬。 相似文献