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81.
Twenty stifles (10 dogs) were studied for a period of 1 year after various lesions of the cranial cruciate ligament and medial meniscus were produced surgicaoy. Through serial arthroscopic evaluations, degenerative processes In stifles with a "torn" cranial cruciate ligament were documented. Intra-articular changes were minimal after partial meniscectomy and were severe after total meniscectomy. Multiple arthroscopies caused no demonstrable changes. 相似文献
82.
B J Culliton 《Science (New York, N.Y.)》1989,245(4919):697-698
83.
Antiserum to a partially purified neuraminidase fromPasteurella multocida, type A:3, was adsorbed with protease-digestedP. multocida type 3 lipopolysaccharide (LPS) to remove LPS immunoreactivity. The LPS-adsorbed antineuraminidase caused a 77% reduction in the neuraminidase activity of homologousP. multocida in anin vitro enzyme neutralization test. All 14 mice passively immunized with the adsorbed antineuraminidase were protected against challenge infection with homologousP. multocida in a mouse protection test. Ten out of 14 mice in one group that received antisera containing antibodies to both neuraminidase and LPS were protected. In contrast, only 1 out of 14 mice that were immunized with pre-immune serum survived the challenge. These results suggest that antiserum toP. multocida neuraminidase was, at least partly, responsible for the protection observed in this study. Neuraminidase may be one of the immunogenic protective proteins present in aqueous extracts ofPasteurella multocida. 相似文献
84.
J B Herrick 《Journal of the American Veterinary Medical Association》1992,201(12):1854-1855
85.
1. White blood cell responses of broilers, turkeys and ducks were examined at regular intervals after being subjected to various degrees of food restriction. 2. Restricted-fed broilers showed increases in heterophil and basophil numbers, together with a corresponding decrease in lymphocytes. The heterophil/lymphocyte ratio was raised. There were no differences between broiler strains. 3. After only one week of feeding restricted diets, heterophils were significantly raised in selected and unselected 2-week-old ducks. At 21 weeks of age, those ducks receiving 50% of food required to achieve their ad libitum-fed body weight had raised heterophils. 4. Ducks receiving food to achieve 25% of ad libitum-fed birds produced a marked basophilia, but no heterophilia. 5. After two weeks of food restriction, turkeys responded with significant heterophil/lymphocyte ratios following two degrees of restricted feeding. 6. It was concluded that in some poultry, a heterophilia may be the response to mild to moderate stress but a basophilia may result after severely stressing birds. 相似文献
86.
Three-week-old weaned and colostrum-deprived neonatal (less than 1 day old) pigs were inoculated to determine the pathogenicity of 2 enterotoxigenic Escherichia coli isolates that do not express K88, K99, F41, or 987P adhesins (strains 2134 and 2171). Strains 2134 and 2171 were isolated from pigs that had diarrhea after weaning attributable to enterotoxigenic E coli infection. We found that both strains of E coli adhered in the ileum and caused diarrhea in pigs of both age groups. In control experiments, adherent bacteria were not seen in the ileum of pigs less than 1 day old or 3 weeks old that were noninoculated or inoculated with a nonpathogenic strain of E coli. These control pigs did not develop diarrhea. Antisera raised against strains 2134 and 2171 and absorbed with the autologous strain, grown at 18 C, were used for bacterial-agglutination and colony-immunoblot assays. Both absorbed antisera reacted with strains 2134 and 2171, but not with strains that express K99, F41, or 987P adhesins. A cross-reaction was observed with 2 wild-type K88 strains, but not with a K12 strain that expresses K88 pili. Indirect immunofluorescence with these absorbed antisera revealed adherent bacteria in frozen sections of ileum from pigs infected with either strain. We concluded that these strains are pathogenic and express a common surface antigen that may be a novel adhesin in E coli strains that cause diarrhea in weaned pigs. 相似文献
87.
Rostral and caudal rhinoscopy in dogs and cats facilitates the investigation of the nasal cavity and accurate biopsy. Rostral rhinoscopy can be performed by rigid endoscopes; caudal rhinoscopy requires flexible endoscopes. Deep anaesthesia or additional analgesia with local anaesthesia is necessary. The nasal cavity is assessed by its form, colour, surface of the mucous membrane, hyperemia, plaques, lesions, and the secretion is assessed by its quantity, colour and viscosity. Foreign bodies and neoplasia must also be looked for. Case reports with abnormal findings are described. 相似文献
88.
A S Waldvogel G A Anderson D L Phillips B I Osburn 《Comparative immunology, microbiology and infectious diseases》1992,15(1):53-63
Bluetongue virus infection in sheep and cattle during fetal development causes neuropathology. Two strains of bluetongue virus serotype 11 designated as UC-2 and UC-8 have different virulence patterns in newborn mice. These viruses have distinctly different electropherotype patterns on polyacrylamide gel electrophoresis indicating a genetic difference in these two viruses of the same serotype. Four bovine fetuses each were inoculated intramuscularly with either UC-2 or UC-8, and one fetus was inoculated with placebo. The inoculation was made intramuscularly through the uterine wall at 120 days' gestation, and the bovine fetuses were recovered by cesarean section 12 or 20 days after inoculation. Fetal blood was collected for virus isolation and serology. Virus was reisolated from brain, blood, lung and liver. Both strains, UC-2 and UC-8, cause severe lesions in the 120 day fetuses. The encephalomalacic lesions occurred earlier and were more severe in fetuses inoculated with UC-8 as compared to those inoculated with UC-2. The subtle differences observed in the fetuses inoculated with the two different strains suggest that there is a difference in pathogenic potential of the two viruses. These differences do not appear to be completely dependent upon the host species. 相似文献
89.
E Bezirtzoglou M B Romond C Romond 《Comparative immunology, microbiology and infectious diseases》1992,15(1):71-74
Studies were undertaken to determine the regulation of the bacterial intestinal implantation in 19 newborns delivered by caesarean section. Correlation was made with the infant feeding mode. The effect of human milk seemed to be the result of B. bifidum proliferation, in contrast to artificial alimentation that seemed to favour C. perfringens implantation. The question was raised by us as to whether this opposition was only related to alimentation. In fact, B. bifidum itself also had an effect as demonstrated by the lower mean counts of C. perfringens in bottle-fed infants carrying the bifido-bacterial flora (P = 0.05). None of the other faecal bacteria investigated in this study led to the same decrease. 相似文献
90.
To investigate the neuropathogenesis of feline immunodeficiency virus (FIV) infection in vitro, we have utilized three populations of cultured feline neural cells (astrocytes, microglia, brain endothelium) to assess the relative susceptibility to FIV infection, ability to produce viral antigens, and effects of infection on cell survival. Astrocytes appeared to be the most susceptible to infection, followed by microglia, whereas brain endothelial cells were relatively resistant to infection. Astrocyte infection resulted in syncytium formation and cell death, while microglial cells remained persistently and productively infected, without obvious cytopathic effects. These results suggest that FIV entry into the central nervous system probably does not occur via infected endothelium and that both astrocytes and microglia are more likely target cells for the virus. 相似文献