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31.
Hagemoser WA 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1989,18(1):17-20
An intravenous bile acid loading test was performed on 16 goats using various dosages and sampling protocols. A recently developed enzymatic bile acid assay provided an economical and technologically simple method for bile acid analysis. Intravenous injection of bile salts into goats was well tolerated. Clearance times were rapid. A protocol for performance of the test was suggested and a practical reference range for T 1/2 clearance of 4+/-1 minute was determined. Further investigations of this test in the assessment of liver function in the ruminant appear warranted. 相似文献
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V Bitsch 《Acta veterinaria Scandinavica》1978,19(1):110-128
A study of the basic reaction in neutralization of virus (V) by virus-neutralizing antibody (VNA) was performed with infectious bovine rhinotracheitis virus and serum collected from naturally and experimentally infected cattle after the primary immunization phase. In constant-virus/varying-serum neutralization tests a direct proportionality between VNA titer and length of preincubation was observed and found to be in accordance with basic laws of neutralization. A deviation from this direct proportionality, which was partly attributed to the presence of a dissociable V-VNA complex, was seen with relatively short preincubation. Expressing a relationship between VNA titer, length of preincubation, and virus dose under conditions where a dissociable V-VNA complex can be ignored, a log. VNA/log. V equivalence factor of neutralization was introduced. A linear relationship was found between VNA titer, taken logarithmically, and preincubation temperature. A rise in temperature by 10°C gave an increase in VNA titer of approx. 1.2 in log2. Formulae are presented for the neutralization rate factor corrected for a demonstrated invalidity of the percentage law, and for the relation between the neutralization rate factor and VNA titer. It is concluded that the results presented have elucidated the possibilities of improving the sensitivity of neutralization tests. 相似文献
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Bérénice Agnola Stéphane Boury Claudie Monot Anne Quillévéré Yves Hervé Drissa Silué 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(5):471-478
A rapid resistance/susceptibility test for Peronospora parasitica (downy mildew) was established by inoculating leaf-disks of four Brassica oleracea accessions. Several conditions were tested: disk disinfection or not, agar medium with or without nutrients and with 50 or 100 ppm of benzimidazole. Using disinfected disks placed on agar (no nutrient and benzimidazole at 50 or 100 ppm), the responses of leaf-disks to four isolates were similar to those obtained using the classical cotyledon test, whereas undesired contaminations occurred in all other conditions. The possible effect of the particular leaf used for obtaining the disks was also studied. In each incompatible interaction tested, disks were resistant whatever the leaf used. In compatible interactions, susceptible phenotypes were observed on disks derived from the six lowest leaves, but disks from upper leaves were resistant. The genetic basis of resistance in a F1 hybrid broccoli was assessed, by testing six isolates on an F2 population derived from this hybrid. The cotyledon test only allows inoculation of two isolates per seedling, whereas many isolates can be tested on each plant by using leaf-disks. The segregation of the resistance to each of the six isolates was analysed: two dominant genes (tightly linked) control resistance to all isolates (one to five isolates; the other to only one isolate). 相似文献
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规模化猪场大肠杆菌的耐药性监测及血清流行病学调查 总被引:40,自引:0,他引:40
为了调查猪致病性大肠杆菌的耐药性及流行血清型 ,从湖北、河南、江西、安徽、浙江等省的 33个猪场采集 32 1份仔猪黄、白痢病料进行细菌的分离和生化鉴定 ,结果分离到大肠杆菌 30 2株 ,其中致病性大肠杆菌 2 76株。对 112株致病性大肠杆菌进行了 15种抗生素敏感性试验 ,发现分离菌株对 15种药物均有不同程度的耐药性 :青霉素 G对其完全没有抑制作用 ;先锋霉素 抑制作用最强 (97.3% ) ,其次为呋喃妥因 (78.6 % )、痢特灵 (71.4 % )、环丙沙星(6 8.8% )、诺氟沙星 (6 5 .1% )。 112株菌中 ,有 4 7种耐药谱型 ,多数为 6耐以上的菌株 (80株 ) ,占供试菌株的 71.4 %。应用微量平板凝集试验 ,对分离的 2 76株致病菌进行了血清型鉴定 ,鉴定共有 72种血清型 ,其中优势血清型 10种 ,占能定型分离致病菌株的 5 3.7%。 相似文献
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