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91.
Figueroa-Chávez D Segura-Correa JC García-Márquez LJ Pescador-Rubio A Valdivia-Flores AG 《Tropical animal health and production》2012,44(7):1417-1421
A cross-sectional study was carried out, from November 2007 to March 2008, to estimate the prevalence of and to determine risk factors associated with bovine syncytial respiratory virus (BRSV) and parainfluenza 3 virus (PIV3) in dual-purpose herds in Colima, México. One hundred and seventy-six sera from 33 herds for PIV3 and 232 sera from 44 herds for BRSV were used. Sera were analyzed by indirect ELISA for the detection of antibodies against BRSV and PIV3 in cattle herds to determine the seroprevalence of respiratory diseases. The apparent and true prevalences for PIV3 were 60.8% and 54.4% and for BRSV 52.2% and 50.8%, respectively. The percentage of herds showing at least one positive animal was 78.7% for PIV3, and 93.2% for BRSV. Age (≤12, 13-48, and >48?months old) and respiratory signs (no, yes) showed significant association (P?0.05) with PIV3 and age with BRSV. This study showed that animals were exposed to both viruses and that age was the main risk factor. The need to establish new vaccination plans to effectively protect cattle against those infections in the state of Colima, Mexico is suggested. 相似文献
92.
93.
建立15株分泌抗水稻细菌性条斑病(RBLS)特异性单克隆抗体(McAb)的杂交瘤细胞。对RBLS病菌呈阳性反应,与植物病原细菌5个属的其它检测菌株均无交叉反应。以酶联免疫吸附试验(ELISA)间接法对30份人工接种稻种进行检测,28份呈阳性反应,检出阳性率达93.3%;对46份病田稻种进行检测,36份呈阳性反应,10份呈阴性反应。取检测为阳性反应中的11份病田稻种的浸出液接种稻苗,有7份发病;而10份检测阴性反应的病田稻种浸出液的接种稻苗均无发病。该检测法灵敏度为0.0125-0.00125mg/ml(蛋白浓度)。 相似文献
94.
95.
Defeng Zhang Xiaoli Ke Lihui Liu Maixin Lu Cunbin Shi Zhigang Liu 《Aquaculture International》2018,26(3):885-897
Several outbreaks of Streptococcus agalactiae infection of bighead carp (Aristichthys nobilis) were observed in China. The molecular epidemiology and pathogenicity of S. agalactiae in bighead carp and tilapia (Oreochromis sp.) is poorly understood. In the present study, we identified S. agalactiae strains isolated from diseased bighead carp using the API 20 Strep kit and 16S rDNA sequencing and determined whether these strains came from tilapia. Of the 46 identified S. agalactiae strains, 24 strains were successfully isolated from diseased bighead carps, 20 S. agalactiae strains were isolated from tilapia, and two S. agalactiae strains were isolated from tiger frog (Hoplobatrachus chinensis). The results of molecular typing, including multilocus sequence typing, molecular serotyping, surface protein gene detection, and virulence-related gene detection showed that the 44 strains from bighead carp and tilapia were highly similar, whereas different from tiger frog GBS strains. Remarkably, the bighead carp strain Hn1404 showed high virulence in bighead carp and zebrafish. Moreover, this strain was pathogenic to Nile tilapia (Oreochromis niloticus). In addition, comparative genomic analysis showed that isolate Hn1404 had a close relationship with the bighead carp and tilapia S. agalactiae strains. All the analyses of the genetic characteristics of bighead carp and tilapia strains showed that tilapia S. agalactiae strains could be transmitted to other fish species such as bighead carp. 相似文献
96.
Xiang-Ming Qi E. Liao Lu Wang Hong Lin Chang-Hu Xue 《Journal Of Aquatic Food Product Technology》2013,22(4):597-606
ABSTRACTThe isoelectric solubilization/precipitation (ISP) process was applied to Antarctic krill protein extraction. The solubility of Antarctic krill proteins and their fluoride content were studied between pH 1.00–13.75. The previous krill protein extraction conditions using ISP were improved. Excess fluoride in Antarctic krill was removed using a water-washing method according to its solubility. To save water, a multistage countercurrent system was used to optimize the ISP method. The results showed that the solubility of Antarctic krill proteins reached a minimum at pH 4.5 and a maximum at pH 13.5, while the concentration of dissolved fluoride was relatively unchanged (16.78–20.50 mg/L), with pH 2.00–13.50. Water-washing 4 times could reduce fluoride 98.14 ± 0.01% from krill with about a 5.14 ± 0.21% protein loss. The reduction allows krill protein to meet the Chinese National Standard (GB 2762-2005) for fluoride. Meanwhile, the four-stage countercurrent system achieved almost the same high fluoride removal rate (98.58 ± 0.01%) using only 25% of the water. 相似文献
97.
98.
为评价国产狂犬病病毒ELISA抗体检测试剂盒的性能,选择4种国产品牌ELISA抗体检测试剂盒,分别检测463份已用荧光抗体病毒中和试验(FAVN)测知狂犬病病毒抗体效价的犬血清,用Kappa检验和配对卡方检验评价ELISA试剂盒与FAVN检测结果的一致性和差异性,计算ELISA试剂盒的诊断敏感性、诊断特异性、符合率和重复性等,并比较4种试剂盒的使用范围、样品稀释倍数等参数。结果显示:经Kappa检验,4种试剂盒与FAVN一致性均为弱;经配对卡方检验,A、B试剂盒与FAVN检测结果的差异不显著(P> 0.05),而C、D试剂盒差异显著(P <0.05)。诊断敏感性,D试剂盒最高,B试剂盒最低;4种试剂盒诊断特异性均较低,为29.5%~57.7%;各试剂盒符合率相当,为71.3%~72.8%。综合敏感性、特异性、重复性等考量因素,得出C试剂盒更能满足免疫后抗体检测需求,A试剂盒也较好,两者可作为候选试剂盒。结果表明,4种国产狂犬病病毒ELISA试剂盒的诊断敏感性、诊断特异性、批间稳定性等性能需进一步提高,以满足基层免疫抗体监测需求。 相似文献
99.
基于内蒙古100个气象站点1960-2014年日降水数据,选取气候变化监测与指数专家组(ETCCDI)推荐的9个极端降水指数,采用Sen’s斜率法和Mann-Kendall非参数统计检验方法以及空间地统计方法,研究了极端降水指数时空演变特征。结果表明:研究区区域平均的全部极端降水指数均呈不同程度的下降趋势,且年际波动显著;分区的年际趋势有所差异,即东部地区潮湿日数(NW)呈增加趋势,其余极端降水指数均呈减少趋势,其中持续干燥指数(CDD)呈显著下降趋势(P<0.05);中部地区所有极端降水指数均呈减少趋势,其中年总降水量(PRCPTOT)减少趋势较明显;西部地区持续湿润指数(CWD)、强降水量(R95)、单日最大降水量(Rx1day)、5日最大降水量(Rx5day)呈减少趋势,其余指数均呈增加趋势。从极端降水指数变化趋势的空间分布特征来看,区域差异显著,总体上呈下降趋势的站点主要分布于内蒙古东部和中部地区,而呈上升趋势的站点主要分布于内蒙古东北部和西部地区。 相似文献
100.
贵德黑裘皮羊耳成纤维细胞系的建立和生物学特性的研究 总被引:4,自引:1,他引:4
以贵德黑裘皮羊耳缘组织为材料,采用组织块贴壁培养法和细胞冷冻技术成功构建了成纤维细胞系,并对培养细胞进行了形态学、生长动力学观察、细胞活力测定、核型分析和微生物检测。结果表明:细胞群体倍增时间(PDT)约为36h,冻存前细胞活力为96.2%,以DMEM/F-12+20%FBS中添加10%DMSO冻存成纤维细胞,解冻后细胞活力为93.6%,24h后的贴壁率为85%。在传代10次之前,细胞染色体中二倍体(2n=54)占主体,约为82%~90%,细菌、真菌、病毒、支原体检测为阴性。该细胞系的建立,使贵德黑裘皮羊这一国家重要种质资源在细胞水平上保存下来,也为体细胞克隆等研究提供了理想的生物材料。 相似文献