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11.
Vibrio anguillarum is an important bacterial pathogen of aquatic organisms and a significant problem in aquatic farming. The rapid detection
and identification of V. anguillarum, and other pathogens that infect marine organisms, is crucial to effective disease management. In this study, we developed
a loop-mediated amplification (LAMP) assay to detect V. anguillarum in an hour in a single tube without the need for thermal cycling. Conserved regions of the metalloproteinase (empA) gene of V. anguillarum served as the targets for primer design. A fragment of the empA gene was amplified at 65°C in the presence of the primer mixture and Bst DNA polymerase. In the optimized LAMP assay, 6.7 pg of V. anguillarum DNA could be detected. Six strains of V. anguillarum and 17 strains of non-V. anguillarum bacteria were used in this study to evaluate the species specificity of the primers. The six V. anguillarum strains gave a positive result in the LAMP assay. This method was also validated in V. anguillarum-infected fish. This LAMP method is more sensitive than PCR in the detection of V. anguillarum and shows good species specificity. The LAMP assay is therefore an effective method for the quick detection of V. anguillarum both in the laboratory and in the field. 相似文献
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本文总结MVT铅-锌矿床的最新地球化学研究方法及研究成果,包括δ18O、87Sr/86Sr、δ34S、206Pb/204Pb、Cl/Br、δ44Ca、同位素定年,以及利用地球化学参数所进行的数值模拟等。以这些方法的研究成果为依据,结合对白云石化作用和有机质在成矿系统中作用的分析,深入探讨了MVT铅-锌矿床的成矿系统,总结出一个与有机质密切相关的流体混合成矿假说。另外,强调了最新研究成果——金属硫化物和脉石矿物相异的流体包裹体成分,将在今后成矿系统的研究中发挥重要作用。 相似文献
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Nengping Shen Zhengwei Zhang Fuhua You Jiantang Peng Xiaoqing Zhu Jiafei Xiao 《中国地球化学学报》2012,31(4):362-375
The polymetallic(Pb,Zn,Cu,etc) ore belt on the southwestern margin of Tarim is one of the major regions with the greatest prospecting potential in Xinjiang.Reported in this paper are the lead isotope data for 66 sulfide samples(including 50 galena samples,15 chalcopyrite samples and 1 pyrite sample) collected from such representative deposits as Tamu,Tiekelike,Kalangu,Abalieke,etc.in this ore belt.The Pb isotopic ratios of 206 Pb/204 Pb,207 Pb/204 Pb and 208 Pb/204 Pb in the galena samples range from 17.931 to 18.176,15.609 to 15.818 and 38.197 to 38.944,with the average values of 18.017,15.684 and 38.462,respectively.Those in the chalcopyrite samples range from 17.926 to 18.144,15.598 to 15.628 and 38.171 to 38.583,with the average values of 18.020,15.606 and 38.262,respectively.The pyrite sample has the Pb isotopic ratios of 206 Pb/204 Pb,207 Pb/204 Pb and 208 Pb/204 Pb to be 17.980,15.604 and 38.145,respectively.In combination with the previous Pb isotope data for sulfides,it is found that there is only a slight variation in the Pb isotopic composition of galena,chalcopyrite,sphalerite and pyrite in the ore belt.However,there is some difference in Pb isotopic characteristics between galena and chalcopyrite,especially the Pb isotopic composition of galena shows an obvious linear correlation with some other relevant parameters(e.g.β and γ).The comprehensive analysis suggested that lead in galena(maybe including sphalerite and pyrite) was derived principally from wall rocks and underlying basement,and that in chalcopyrite only originated from the basement.The single-stage model ages of these sulfides couldn’t indicate the time limit of metallogenesis(Pb,Zn,Cu,etc.),and the positive linear correlations for the Pb isotopic composition of galena are of no single-stage and two-stage Pb-Pb isochron significance.Furthermore,there are significant differences in Pb isotopic composition characteristics between the genetic type of deposits in this polymetallic ore belt and the Mississippi Valley type(MVT).In addition,the authors also pointed out that there is a phenomenon of differentiation(not paragenesis) for lead and copper elements during the process of metallogenesis in this ore belt. 相似文献
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为了建立鲁中地区土壤水分精细化预报模型,利用2010—2013年农田土壤水分自动站逐日资料进行土壤水分年、月变化特征研究,并结合附近自动气象站资料,以土壤水分平衡方程、农田蒸散模型为基础,采用逐步回归和曲线估计等方法建立4—6月无降水条件下平原水浇田与山旱田土壤水分1 d、7 d降幅的经验预报模型。结果表明:鲁中地区0~100 cm土壤水分贮存量年变化趋势和0~50 cm基本一致,年最高出现在8月,最低出现在6月,年降幅最大出现在3—6月,易出现干旱。对预报模型进行回代和预报检验结果显示,回代平均相对误差为0.07%,7 d模型和1 d模型滚动预报第7天0~50 cm土壤水分贮存量,绝对误差分别为-0.15和-2.17 mm,平均相对误差分别为-0.07%和-1.56%,模型具有较强的理论基础和实用性,预报精度较高,为鲁中地区土壤墒情监测和精细化预报提供支持。 相似文献
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通过对成都地磁台的仪器配置、误差来源、资料质量等方面进行综合分析,结果表明.成都地磁台的观测质量稳定,资料连续可靠。成都地磁台的观测能够正确反映成都地区地磁场的变化特征。 相似文献
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锯缘青蟹(Scylla serrata)幼体胃磨发育的比较研究 总被引:6,自引:1,他引:6
在青蟹幼体发育过程中,胃磨呈现出明显的变化。Z1缺乏胃磨的结构,ZⅡ开始出现中齿和侧齿的雏形,明显的可以识别的中齿和侧齿出现在ZⅢ,.从ZV开始胃磨已臻完善,除具有中齿和侧齿外,还出现了4个附属齿,包括两个附属的中齿和两个附属的侧齿。大眼幼体期,中齿和侧齿比ZV更加尖锐,附属齿也更加锋利。在仔蟹前,中齿齿尖发生特化,形成垫状角质化区域,侧齿、附属齿更加锋利。这表明青蟹幼体发育过程中胃磨结构的变化与 相似文献
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