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71.
泥蚶34个EST-SSR标记的开发及在格粗饰蚶中的通用性检测   总被引:1,自引:0,他引:1  
利用泥蚶转录组高通量测序、拼接获得的大量EST序列开发SSR标记,在1123条EST序列里筛查到73条含有SSR位点的EST序列,其中54个位点适合设计引物,在位点两侧设计引物并进行PCR扩增.结果显示,46对引物获得稳定扩增的位点,引物在泥蚶奉化群体的多态性检测中发现,有34对引物表现出多态性,共扩增出122个等位基因,各位点的等位基因数Na为2~7个,平均每个位点产生3.59个等位基因,观测杂合度Ho、期望杂合度He、多态信息含量PIC范围分别为0.000 ~ 0.600、0.078 ~0.771、0.106~0.718;Hardy-Weinberg平衡检测显示,13个位点偏离了平衡状态;用Nr和Swiss-Prot蛋白质数据库对含有多态性SSR的EST进行了基因注释,25个SSR位点来自注释基因序列.将34对泥蚶多态性SSR引物在格粗饰蚶中进行了通用性检测,结果有1 1对成功扩增,8对表现为多态,通用率为23.53%,这些通用引物可用于两种蚶的遗传多样性评价、系统进化分析、比较作图和基因发掘等研究.  相似文献   
72.
健康和患病凡纳滨对虾幼虾消化道菌群结构的比较   总被引:2,自引:1,他引:1  
凡纳滨对虾养殖过程中,早期阶段是病害易感阶段,而消化道菌群结构与对虾健康关系密切。因此,探讨幼虾的消化道菌群尤其是弧菌类细菌与对虾发病的关系对病害有效防治具有重要意义。本实验采用Illumina测序研究了凡纳滨对虾健康和患病幼虾的消化道细菌群落结构,并基于纯培养和16S r DNA,rec A和pyr H基因序列比对,分析了幼虾消化道中弧菌的主要种类组成。结果发现,健康幼虾消化道中α-变形菌纲和厚壁菌门丰度较高,而患病幼虾中γ-变形菌纲、拟杆菌门、放线菌门和β-变形菌纲较高,其中放线菌门丰度差异显著。基于科水平的响应比分析,发现患病幼虾消化道中动性球菌科和噬菌弧菌科的丰度显著降低,而弧菌科的丰度显著升高。相似度分析发现,驱动群落变异的OTU主要来源于弧菌属、海洋杆状菌属、冷杆菌属、假交替单胞菌属以及未分类至属的红杆菌科和微杆菌科。健康幼虾消化道弧菌组成以锡那罗亚州弧菌为主,而患病幼虾消化道弧菌组成以坎氏弧菌为主。尽管健康和患病幼虾消化道内细菌群落结构整体差异不显著,但一些重要类群丰度变化显著,其特征与已知的生态功能一致。  相似文献   
73.
培养基对微生物被膜形成和厚壳贻贝附着的影响   总被引:2,自引:2,他引:0  
为探讨微生物被膜生物学特性、培养基以及大型生物附着三者之间的相互关系,本实验通过微生物分子生态学和海洋贝类生态学等方法调查了不同培养基对海洋细菌所形成微生物被膜的影响及其对厚壳贻贝幼虫附着的影响。结果显示,厚壳贻贝稚贝率与培养基类型和细菌初始密度显著相关,进一步分析表明,Zo Bell 2216E和Seawater Luriabertani(SWLB)条件下分别有6株和9株细菌形成的微生物被膜密度与稚贝率显著相关。扫描电镜结果显示,Staphylococcus sp.3在Zo Bell 2216E培养基条件下形成微生物被膜的细菌分布较为紧密,Pseudoalteromonas sp.8则在SWLB培养基条件下微生物被膜细菌分布较为紧密,且形态变为短杆状。SDS-PAGE结果显示,相比Zo Bell 2216E培养基,Staphylococcus sp.3在SWLB培养基条件下9条条带蛋白显著下降,其中2个条带完全消失;Pseudoalteromonas sp.8则在SWLB培养基条件下明显增加5条蛋白条带。研究表明,微生物被膜的形成受到培养基的影响,培养基的不同导致微生物被膜的形态结构、分布和蛋白有所差异,最终导致微生物被膜诱导厚壳贻贝幼虫附着变态的活性差异,本研究为后续开展厚壳贻贝附着的分子机制奠定良好基础。  相似文献   
74.
Uranium is a radiotoxic and chemotoxic heavy metal. Uptake and accumulation of U has been studied in plants native to uranium mine sites, but not in cultivated plants which are commonly consumed by humans. The objective of this study was better understanding of U uptake and accumulation in cultivated plants and whether different contents of uranium (U) in the substrate affect its concentration in plants and their dry matter mass. Two substrate variants for growing plants, which differed in the uranium content: solid wastes (tailings) and tailings mixed with sand (w/w 1:1). Large amounts of solid wastes (tailings) resulting from the exploitation and treatment of uranium ore from the closed uranium mine Gabrovnica–Kalna, on southeast of Serbia, contained generally 15.33 mg U/kg. In the experiment, three plant species (corn NSSC 231, sunflower N.S. Dukat, and green peas Smederevska Palanka) were grown in pots on the four substrate variants during 40 days. Substrate was suffused by drinking water (DW) and “uranium water” (UW), which issue out from the mine, contained 0,053 mg U/ dm3. Obtained results show that when UW was added to tailing concentration of U in plants increased. When the content of U in the substrate was lowered by adding sand, the concentration of U in plants decreased, though was significantly higher in comparison to the variants to which DW was added. Dry matter mass was higher in variants where UW was used. Concentration of U was significantly higher in root than in above-ground parts.  相似文献   
75.
The content of As and heavy metals (Pb, Cd, Ni, and Cu) in total suspended particulate (TSP) and PM10 at 3 locations (Park, Institute, and Jugopetrol) near the copper smelter in Bor (Serbia) has been analyzed within the period 2004 to 2015 with the aim of investigating the seasonal and spatial changes of those pollutants in the suspended particles. The content of As in TSP and PM10 was over the annual EU limit value at all measuring points during the entire period of observation, while contents of Cd and Pb were periodically above the annual EU limits. There were no statistically significant seasonal changes between mean levels of the observed elements in the cold (October–March) and warm (April–September) periods during the year. A strong and moderate positive correlation was detected between the concentrations of each particular element (except Ni) at all measuring points. Additionally, Cd was the most enriched element followed by Pb, As, and Cu, while Ni was low-enriched. The constant air pollution with As particles, sometimes in concentrations even 20 times higher than the permitted annual value, requires urgent undertaking of concrete actions in order to reduce anthropogenic emission of suspended particles in Bor.  相似文献   
76.
公共选修课是我国高校课程体系的重要组成部分,其开设数量和质量直接影响到高等教育人才培养的质量.通过对南京森林警察学院公共选修课学生满意程度进行的问卷调查,分析学生对于选课方式、授课教师、结课方式、课程种类及教学模式等方面的满意程度,发现公共选修课开设过程中存在着课程体系缺乏系统性,学生选课比较随机;高水平选修课程不足,教学质量有待提高等问题.建议:加强学生选课的系统指导,减少学生选课的随机性;提高教师的教学热情,重视教学质量的提高;提高课程设置的质量,丰富公共选修课的数量;完善选修课程教学制度,加强教学的监管力度.  相似文献   
77.
It is common knowledge that humic substances extracted from different sources are characterized by high biological activity (BA), though the nature of this phenomenon is not quite clear up to now. To expand our understanding of the BA of humic substances, we studied the effect of humates prepared from humic acids of different origin on the germination of seeds. The efficiencies of seed treatment by humate solutions obtained from preliminary purified humic acids extracted from peat, coal, and soil differed insignificantly. At the same time, the solutions of salts of humic substances obtained via alkaline extraction from peat without subsequent purification did not lead to statistically significant biological effects. The analysis of literature and our own data allowed us to conclude that the biological activity of humic acids could be related to their capacity to regulate the growth processes via binding growth inhibitors released into the solution upon seed swelling into the supramolecular complexes.  相似文献   
78.
The total content of phenolic compounds (TAP) in 29 different monocultivar olive oil samples from France (Aglandau and Tanche) and Spain (Cornicabra, Picual, and Verdial) was assessed by the colorimetric Folin-Ciocalteu method. Also, individual phenolic compounds were determined and quantified by liquid chromatography coupled to mass spectrometry (LC-MS). The French olive oil samples had a lower TAP compared to Spanish samples. The quantity of individual phenolics was similar except for pinoresinol, which was lower in the French olive oil samples. TAP moderately correlated to the sum of quantified compounds (r = 0.64 and p < 0.01) Partial least-squares (PLS) regression analysis emphasized the importance of hydroxytyrosol and the total amount of quantified phenolic compounds by LC-MS in the prediction of the total amount of phenolic compounds as determined by the Folin-Ciocalteu method. The amount of alpha-tocopherol was generally different among the cultivars (Tanche > Picual > Verdial > Aglandau > Cornicabra). Of all quantified phenolic compounds in French olive oil samples, only luteolin correlated well to the altitude of the olive orchards (r = 0.76, p < 0.01).  相似文献   
79.
Plant Foods for Human Nutrition - A simple and efficient ultrasonic-assisted extraction (UAE) technique was developed in order to find optimal conditions for the extraction of total phenolic...  相似文献   
80.
The phosphoinositide phosphatase PTEN is mutated in many human cancers. Although the role of PTEN has been studied extensively, the relative contributions of its numerous potential downstream effectors to deregulated growth and tumorigenesis remain uncertain. We provide genetic evidence in Drosophila melanogaster for the paramount importance of the protein kinase Akt [also called protein kinase B (PKB)] in mediating the effects of increased phosphatidylinositol 3,4,5-trisphosphate (PIP3) concentrations that are caused by the loss of PTEN function. A mutation in the pleckstrin homology (PH) domain of Akt that reduces its affinity for PIP3 sufficed to rescue the lethality of flies devoid of PTEN activity. Thus, Akt appears to be the only critical target activated by increased PIP3 concentrations in Drosophila.  相似文献   
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