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梨火疫细菌实时荧光PCR和诱捕PCR-ELISA检测方法的建立 总被引:8,自引:1,他引:8
根据梨火疫细菌中独特而保守存在的质粒pEA29,设计了1对引物和3条探针,建立了实时荧光PCR检测方法和诱捕PCR-ELISA检测方法。实时荧光PCR采用带荧光标记的核酸杂交探针,边扩增边检测,步骤简单,不需PCR后处理,可避免假阳性和交叉污染;诱捕PCR-ELISA检测方法只需简单处理的样品就能检测,减少了核酸不纯出现的漏检,由于增加了核酸杂交探针,可不需凝胶电泳EB染色检测,不会出现假阳性问题。 相似文献
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水丰水库的渔获量1961-1980年间变化于47-300t,1981-1984年增长到740-1321t,1985-2000年为2270-4926t。渔获物组成中以亚洲公鱼为主,1980-2000年亚洲蚣鱼占总渔获的29.6%-93.0%,平均为65.6%。鲁鲫鱼占6.2%-16.4%,鲢鳙鱼占8.1%-13.3%,鳊鲂占1.8%-11.3%,虾占5.9%-16.1%,其它鱼类占2.4%-9.3%。2000年大银鱼占总渔获的2.8%。1985-2000年水库鱼类资源相对稳定。亚洲公鱼、青虾和大银鱼三种小型经济鱼虾的种间关系表现为互利共生,竞争和残敌关系,可能向种间形成平衡调节方向发展。 相似文献
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1993年5~11月份、1999年4~10月份和2006年的5~11月份,在地处晋西南的隰县阳头升乡竹干村和后堰村,以铗捕率或笼捕率的变化作为衡量种群数量的标准,开展了对社鼠(Rattus confucianus sacer)种群数量季节消长的研究。结果表明,社鼠种群数量存在着明显的季节变化,主要是繁殖和死亡两大因素相互作用的结果。种群每年在9月份出现一次数量高峰,由5、6、7、8月份的繁殖行为形成。10月份以后,由于气候和食物等条件恶化,致使部分鼠体死亡,特别是上一年越冬鼠的大量死亡,使社鼠种群数量随之下降。 相似文献
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Estimates of population size and density are essential for successful management and conservation of any species. Although there are a variety of methods available for estimating abundance and density of populations, most studies rely on only one estimator and very few studies have compared and critically evaluated the adequacy and the cost of these methods. We used the brown bear (Ursus arctos) in south-central Sweden to compare the performance of three different methods of estimating population size, including methods based on conventional field data as well as on non-invasive genetic data. The method based on observations of females with cubs underestimated the true population size, as the estimates were below the number of unique genotypes determined from faecal data inside the study area. The best traditional method was based on observations of bears from a helicopter. The genetic method using the closed population MARK estimator, as recommended in a previous study, seemed to perform the best. We conclude that approximately 223 (188-282) bears were present in our 7328 km2 study area during 2001 and 2002 and suggest that this hunted brown bear population has been relatively stable for about ten years. The non-invasive genetic method was less expensive than the most reliable traditional field method (a CMR method based on observations of bears from a helicopter), and preferable from an ethical point of view. We recommend that future studies using non-invasive genetic methods based on collected faecal samples should aim at collecting 2.5-3 times the number of faecal samples as the “assumed” number of animals. 相似文献
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用PCV2 Cap蛋白单克隆抗体预包被酶标板,将杆状病毒表达系统表达的PCV2 Cap蛋白作为检测用抗原,利用捕获包被法建立了间接ELISA法用于猪圆环病毒2型抗体的检测.通过优化ELISA条件,研制试剂盒并应用于圆环病毒2型疫苗的免疫效果检验.利用研制的试剂盒与IFA、商品化进口和国产同类试剂盒对178份猪血清进行平行检测,总符合率分别为96.63%、97.75%和84.27%,与其他几种常见猪病毒抗体阳性血清无交叉反应.试剂盒批内、批间变异系数分别为2.35% ~4.06%和4.87% ~ 6.54%,2~8℃保存15个月稳定,适合于对不同来源猪圆环病毒2型疫苗人工免疫猪血清抗体进行检测. 相似文献
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Agricultural activities are frequently associated with water contamination. The spreading and storage of fertilizers, for instance, may result in groundwater contamination due to pollutants leaching into an aquifer. Nitrates and fecal bacteria are two important contaminants associated with agriculture. Thus, the development of efficient strategies for groundwater protection in agricultural areas requires an assessment of these two contaminants. Given this perspective, groundwater quality monitoring was carried out over the whole capture zone of a municipal well located in an agricultural area in the St.-Lawrence Lowlands in Québec. Thirty-eight piezometers were installed within the roughly 2 km2 capture area of the well to measure physico-chemical parameters such as major ions, field measured parameters (pH, electrical conductivity, dissolved oxygen, water level, temperature), and isotopic ratios, bacteriological parameters (Heterotrophic Plate Count—HPC, enterococci, total coliforms, Escherichia coli) and their variations in space and time. Groundwater was sampled from the pumping well and the piezometers during 25 field campaigns in 2005, 2006 and 2007. The results demonstrate the impact of agricultural activities on nitrate contamination. They indicate high spatial and temporal variations in nitrate concentrations, from 6 to 125 mgNO3−/L within the capture area, with 40% of the samples exceeding the Québec drinking water limit of 45 mgNO3−/L. Nitrate pollution in the municipal well exceeded 45 mgNO3−/L during 2005, but no bacteriological contamination was observed. The results also show a high variability of nitrate concentration with depth within the capture zone. Electrical conductivity appears as a good indicator of the presence of nitrate and calcium ions in this capture zone. Correlations between nitrate, calcium and chloride suggest that these ions come from the same source of fertilizer. Nitrate isotopic composition suggests that nitrate in groundwater originates from both chemical and organic fertilizers. The bacteriological results show that the extracted volume of water during sampling of a piezometer has a significant impact on the bacteria count. The variability of bacteriological pollution is important in space and time, showing a higher contamination during summer. Only 2% of the raw water samples exhibit contamination exceeding the drinking water standard for treated water. Total coliforms seem to be a good precursor of E. coli or enterococci contamination. Globally, the physico-chemical and bacteriological groundwater quality within the studied capture area and the pumping well shows contamination by nitrates, but low contamination levels by fecal bacteria. 相似文献
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R. C. Holeva D. J. F. Brown R. H. C. Curtis R. Neilson 《European journal of plant pathology / European Foundation for Plant Pathology》2008,120(1):85-89
Lectins and polyclonal antiserum that bind specifically and reproducibly to the overall surface of Paratrichodorus anemones were identified and bound to monodisperse superparamagnetic particles (Dynabeads) to assess their efficiency as probes for
capturing target nematodes from test suspensions. In recovery experiments, while both types of probe isolated nematodes, antibody-coated
beads recovered them more efficiently than beads coated with lectins. When immunomagnetic capture was used to isolate P. anemones from mixtures of naturally occurring populations of nematodes extracted in bulk, from soil samples, 80% of the target nematodes
were recovered. 相似文献
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用石油醚提取样品,电子捕获检测器检测,其回收率高达80%以上,变异系数为2.36。是测定树皮中百菌清残留量的一个快捷方法。 相似文献