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981.
After intranasal instillation two freshly isolated English strains of Haemophilus taxon 'minor group' produced persistent infection in the tonsil but failed to elicit macroscopic or histological changes in the lower respiratory tract of two pairs of 14-day-old gnotobiotic piglets whereas a freshly isolated English strain of Haemophilus pleuropneumoniae caused a lethal pleuropneumonia in a third pair.  相似文献   
982.
Actinomycotic mycetoma, a chronic, progressive infection of the subcutaneous tissue characterized by tumefaction, draining sinuses, and grains, was diagnosed in the right hindlimb of a young adult, male cat. The organisms that cause actinomycetoma are soil or plant saprophytes that gain entrance to the skin through abrasion or traumatic implantation. Streptomyces griseus, an organism generally considered to be a saprophyte, was cultured bacteriologically. Despite extensive surgery and long-term antibiotic therapy, the infection persisted, and the cat was euthanatized.  相似文献   
983.
The authors examined 585 samples from 92 mares of 2 studs and 346 nasal swabs taken from their foals for the presence of mycoplasmas. The positive rates of mares and foals were 81.5% and 71.7%, respectively, with positivity of samples being variable. Clinical symptoms developed in 2-4 waves and lasted 3-7 days, with intervals of 7-12 days. The disease started in April among foals born in February, at an average age of 88 days. Later on, the average age of the affected foals decreased. There was a correlation between presence of mycoplasmas in nasal cavity and disease of foals.  相似文献   
984.
This study describes the capillary supply of individual regenerating muscle fiber during three stages of its development. Regeneration was induced by the injection of mepivacaine in the anterior tibial muscle of rats. Muscle fiber capillarization during regeneration was analysed in semithin sections, employing the following parameters: the number of capillaries around a fiber and the number of capillaries per fiber cross-sectional area. The results revealed that during development of regenerating fibers, the fiber cross-sectional area increased, the number of capillaries around each fiber increased and the number of capillaries per fiber cross-sectional area decreased. These data indicated a greater capillary supply of the individual regenerating muscle fiber during its early stage of maturation.  相似文献   
985.
986.
An enzyme-linked immunosorbent assay has been shown to detect antibodies in the circulation of sheep infected with Psoroptes ovis. Strong positive reactions were obtained from 19 sheep with four-month-old infections. No cross reaction was observed with sera obtained from sheep infected with either Fasciola hepatica, Nematodirus battus, Ostertagia circumcincta or Damalinia ovis.  相似文献   
987.
Five monoclonal antibodies were obtained after immunising mice with superficial antigens of three strains representing serovars 1 to 3 of Actinobacillus (Haemophilus) pleuro-pneumoniae. When tested in ELISA against the standard strains representing serovars 1 to 10, the monoclonal antibody raised against the standard strain of serovar 1 reacted only with that strain. Of the three monoclonal antibodies raised against the standard strain of serovar 3, one reacted with serovars 3 and 8 only, another with serovar 7 only and the third with the strains representing serovars 7, 9 and 10. The monoclonal antibodies produced with the serovar 2 strain also reacted with a wide spectrum of strains, representing serovars 7 to 10.  相似文献   
988.
989.
990.
A serogroup-specific polymerase chain reaction (PCR) assay and isolate identification strategies (restriction endonuclease analysis (REA) and nucleotide sequencing) were developed for the detection of North American isolates of epizootic haemorrhagic disease virus (EHDV). PCR primers (EHDV-pr4, EHDV-pr5) were designed to hybridize to the L3 gene of a North American isolate of EHDV serotype 1. Total nucleic acid was extracted from preparations of infected tissue culture and PCR was performed using a cDNA-PCR kit, according to the manufacturer's specifications. The PCR assay generated a 459 base pair product from North American isolates of EHDV serotypes 1 and 2, while bluetongue virus (BTV) serotypes 10, 11, 13, and 17, and cell controls, failed to demonstrate PCR products. Slight modifications allowed for the PCR detection of EHDV-1 and -2 in white-tailed deer blood (Odocoileus virginiatus); PCR fragments were not amplified from uninfected deer blood. A number of restriction endonucleases and sequencing primers were evaluated for their utility in isolate identification experiments. Specifically, REA employing HincII and cycle sequencing with an internal primer (EHDV-1-pr3) proved most successful for identifying isolate-specific genome markers. The techniques presented are expected to prove valuable for rapid and specific detection of possible future EHDV incursions in wild and domestic animal species.  相似文献   
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