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991.
Ruiqin Ma Feng He Haishen Wen Jifang Li Bao Shi Dan Shi Miao Liu Weijie Mu Yuanqing Zhang Jian Hu Weiguo Han Jianan Zhang Qingqing Wang Yuren Yuan Qun Liu 《中国海洋大学学报(英文版)》2012,11(1):99-104
As a specific gene of fish,cytochrome P450c17-Ⅱ(CYP17-Ⅱ) gene plays a key role in the growth,development and reproduction level of fish.In this study,the single-stranded conformational polymorphism(SSCP) technique was used to characterize polymorphisms within the coding region of CYP17-Ⅱ gene in a population of 75 male Japanese flounder(Paralichthys olivaceus).Three single nucleotide polymorphisms(SNPs) were identified in CYP17-Ⅱ gene of Japanese flounder.They were c.G594A(p.G188R),c.G939A and c.G1502A(p.G490D).SNP1(c.G594A),located in exon 4 of CYP17-Ⅱ gene,was significantly associated with gonadosomatic index(GSI).Individuals with genotype GG of SNP1 had significantly lower GSI(P < 0.05) than those with geno-type AA or AG.SNP2(c.G939A) located at the CpG island of CYP17-Ⅱ gene.The mutation changed the methylation of exon 6.Indi-viduals with genotype AA of SNP2 had significantly lower serum testosterone(T) level and hepatosomatic index(HSI) compared to those with genotype GG.The results suggested that SNP2 could influence the reproductive endocrine of male Japanese flounder.How-ever,the SNP3(c.G1502A) located in exon 9 did not affect the four measured reproductive traits.This study showed that CYP17-Ⅱ gene could be a potentially useful candidate gene for the research of genetic breeding and physiological aspects of Japanese flounder. 相似文献
992.
将罗氏沼虾(Macrobrachium rosenbergii)在0.1、0.2、0.4 mg/L的壬基酚中暴露48 h,检测壬基酚对罗氏沼虾血清中部分免疫酶活力的影响。结果表明:高剂量壬基酚组(0.4 mg/L)的罗氏沼虾血清超氧化物歧化酶(SOD)活力在前期受到明显抑制(p<0.05),24 h后各剂量组血清SOD活力转为促进,中、高剂量组的SOD活力显著高于对照组(p<0.05);中、低剂量组血清中酸性磷酸酶(ACP)活力均受到抑制,其中12 h低剂量组血清ACP活力显著降低(p<0.05),高剂量组则表现为先促进后抑制的效应;各剂量组血清碱性磷酸酶(AKP)活力先受到抑制后转为促进,48 h中、低剂量组血清AKP活力显著高于对照组(p<0.05)。 相似文献
993.
通过对漳州地震台TJ-Ⅱ型体应变资料的映震效应分析,并利用多种方法对形变前兆异常分析,探讨区域地下形变资料对地震短临预报的实际意义。 相似文献
994.
利用辽宁省地震重点监视防御区工程场地地震安全性评价工作中积累的大量实际钻孔和土工试验资料,在50年超越概率为63%、10%、2%三种地震动输入情形下,采用等效线性化方法研究了辽宁省地震重点监视防御区Ⅱ类场地土层的放大效应。研究结果表明辽宁省地震重点监视防御区50年超越概率10%的平均场地效应放大因子为1.37,若使用《中国地震动参数区划图(GB18306-2001)》认定的系数(1.25)将低估研究区域内的场地放大效应。50年超越概率2%情形即"工程结构抗倒塌水准"的平均场地放大效应因子为1.35。这些结果有益于为研究区域提供更为合理的抗震设防标准。研究同时发现,实际工程中使用单一变量或有限的几个变量去控制场地放大效应会有很大的离散,因此重大工程项目的地震安全性评价工作是不可被替代的。 相似文献
995.
Acid sulphate soil(ASS) is a kind of soil which is harmful to the environment.ASS is hard to efficiently assess efficiently in the subsurface,although it is detectable on the surface by remote sensing.This paper aims to explore a new way to rapidly assess ASS in the subsurface by introducing a proximal hyperspectral instrument,namely the HyloggerTM system which can rapidly scan soil cores and provide high resolution hyperspectral data.Some minerals in ASS,which usually act as indicators of the severity of ASS,such as iron oxides,hydroxides,and sulphates,as well as some clay minerals,such as kaolinite,have diagnostic spectral absorption features in the reflectance spectral range(400-2500 nm).Soil cores were collected from a study area and hyperspectral data were acquired by HyloggerTM scanning.The main minerals related to ASS were characterized spectrally,and were subsequently identified and mapped in the soil cores based on their reflectance spectral characteristics.Traditional X-ray diffraction(XRD) and scanning electron microscope(SEM) were also applied to verify the results of the mineral identification.The main results of this study include the spectral characterisation of ASS and its main compositional minerals,as well as the distribution of these relevant minerals in different depth of cores. 相似文献
996.
A new kinetic spectrophotometric method has been developed for the determination of trace Ni (II) in natural water.The method is based on the catalytic effect of Ni (II) on the oxidation of weak acid brilliant blue dye (RAWL) by KIO4 in acid medium.The concentration of nickel (II) can be determined spectrophotometrically by measuring the decrease of absorbance of RAWL at λ= 626 nm using the fix-time method.The influencing factors are investigated by the orthogonal experimental design.The obtained optimum analytical conditions are:pH=2.00,c RAWL=5.00×10-5 mol L-1,cKIO 4= 2.00×10-5 mol L-1,the reaction time t=10 min and the temperature T=25℃..Under the optimum conditions,the developed method allows the measurement of Ni (II) in a range of 0-40.0 ng mL-1.The standard deviation of eleven independent measurements of blank reaction is S=3.08×10-3 and the limit of detection is 2.20 ng mL-1.The relative standard deviations (RSDs) in six replicate determinations of 5 ng mL-1 and 8 ng mL-1 Ni (II) are 2.87% and 1.11%,respectively.Moreover,the experiments show few cations and anions can interfere with the measurement of Ni (II).The recovery efficiencies of this method are in a range of 97.0%-102.5% in freshwater samples.But there is a decreasing effect,which is about 0.2 times the added Ni (II) in seawater medium.After reasonable calibration this processing method is used for the determination of Ni (II) in seawater samples successfully.The results show this developed method has high accuracy and precision,high sensitivity,large range of linearity and high speed.The method can,therefore,be employed at room temperature. 相似文献
997.
998.
999.
数字编码技术在雷达、医学等方面广泛成功应用使得将其引入地震探测中成为可能。本文为将数字编码技术引入地震探测中,进行了岩石物性成像仿真实验。首先讨论了编码超声成像原理,分析了编码技术的规律和特点。其次通过激励Golay码,利用FieldⅡ软件包进行了岩石物性超声成像的仿真,并比较了仿真结果的成像分辨率。结果表明,编码技术是提高超声成像质量的有效方法。结果可用于指导野外编码地震探测。 相似文献
1000.
笔者对内蒙古朱拉扎嘎金矿做了详细的镜下岩(矿)相学研究工作,首次发现火山岩(包括石英角斑岩,粗面流纹岩,团粒状充纹岩,变矿化流纹岩,蚀变霏细岩等)和其他火山活动的痕迹。改变了过去人们对该矿床成因的认识。火山活动不仅带来了大量熔浆热物质,而且带带来了大量的成矿金属元素,为矿床的形成准备了丰富的物质基础和良好的成矿环境。因此,与中元古代朱拉扎嘎毛道组地层沉积同期发生的火山作用对朱拉扎嘎金矿的形成起着重要的作用。 相似文献