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101.
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
102.
103.
J L López-Rivero E Agüera J G Monterde J Vivo M V Rodríguez-Barbudo 《American journal of veterinary research》1992,53(5):847-850
The mean area and minimal diameter of 3 histochemically determined myofiber types (1, 2A, and 2B; myosin ATPase in acid buffer) were calculated in middle gluteal muscle biopsy specimens from 62 stallions, 47 Andalusians and 15 Arabians, ranging in age from 6 to 12 years. Fourteen Andalusians and 7 Arabians were untrained, and the remainder were actively endurance-trained. The 6-month training schedules involved walking, slow trotting, and cantering. Fourteen Andalusians were moderately endurance-trained, whereas the other 19 Andalusians and 8 Arabians were strongly endurance-trained. Significant differences were not recorded between untrained and endurance-trained Arabians with respect to the area (type 1, 3,194 +/- 869 microns 2 and 3,150 +/- 370 microns 2; type 2A, 3,819 +/- 890 microns 2 and 3,380 +/- 356 microns 2; and type 2B, 4,872 +/- 962 microns 2 and 4,417 +/- 646 microns 2) or minimal diameter (type 1, 52.2 +/- 7.4 microns and 52.8 +/- 3.1 microns; type 2A, 58.1 +/- 6.7 microns and 55.0 +/- 2.8 microns; and type 2B, 65.3 +/- 6.4 microns and 63.4 +/- 4.3 microns) of the 3 fiber types, nor between untrained and endurance-trained Andalusians with respect to the area (untrained, 3,990 +/- 690 microns 2; moderately endurance-trained, 3,882 +/- 347 microns 2; and strongly endurance-trained, 3,758 +/- 510 microns 2) and minimal diameter (untrained, 58.1 +/- 4.7 microns; moderately endurance-trained, 59.7 +/- 2.7 microns; and strongly endurance-trained, 58.7 +/- 4.5 microns) of 2A fibers.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
104.
T. D. G. Watson † D. Gaffhey C. T. Mooney† H. Thompson‡ C. J. Packard J. Shepherd 《The Journal of small animal practice》1992,33(5):207-212
Hyperchylomicronaemia was identified in a four-week-old Siamese kitten with lethargy, in-appetence, hindlimb ataxia and profound anaemia. The kitten was euthanased and at necropsy a thrombus was found occluding the caudal aorta. Two littermates later presented with lethargy, inappetence and hypertriglyceri-daemia which resolved after being weaned on to a low fat diet. A similar condition was subsequently diagnosed in a kitten born to the same sire but a different queen. The expression of hyperchylomicronaemia in two related litters was suggestive of an inherited, familial defect in the function of lipoprotein lipase (LPL). The activity of this enzyme was reduced in all three parents, the two recovered cases and two related, but apparently unaffected kittens, compared with a control group of unrelated cats belonging to the breeder. This reduction in activity was not attributable to defective activation of LPL by its serum cofactor apolipoprotein C-II or the presence in plasma of a factor that inhibited LPL. The gene that codes for LPL was examined by restriction fragment length polymorphism analysis using a human LPL cDNA probe. The results showed that the cat has a similar, but not identical, LPL gene to man. However, there were no differences in the restriction fragment patterns obtained from affected, unaffected and control animals. 相似文献
105.
106.
Estrogen and progesterone receptor status of mammary carcinomas and correlation with clinical outcome in dogs. 总被引:3,自引:0,他引:3
E A Sartin S Barnes R P Kwapien L G Wolfe 《American journal of veterinary research》1992,53(11):2196-2200
Estrogen and progesterone receptors (ER, PR) were measured in cytosol fractions from 18 primary canine mammary carcinomas by use of biochemical assays. One or both receptors were detected (> 10 fmol/mg of cytosol protein) in 11 tumors: 5 ER and PR; 2 ER only; 4 PR only. Mean cytoplasmic receptor concentrations (fmol/mg of cytosol protein) were 22.8 +/- 2.9 (SEM) for ER and 51.0 +/- 10.3 for PR in tumors containing ER and PR, 28.8 +/- 12.1 for ER in tumors containing only ER and 13.2 +/- 1.5 for PR in tumors containing only PR. Estrogen or progesterone receptors or both were identified in 6 of 9 tubular adenocarcinomas, 4 of 5 papillary adenocarcinomas, and 1 of 1 squamous cell carcinoma. These receptors were not identified in solid carcinomas (n = 2) or a single spindle cell carcinoma. Although the number of cases was limited, survival times of dogs tended to be longest in those with tumors containing ER alone or in combination with PR, intermediate in those with tumors containing only PR, and shortest in those with tumors without ER or PR. A correlation was not apparent between receptor status and age, presence of ovaries, tumor size, or histologic classification of the tumor. In the analysis of this series, the extent of surgery (mastectomy of the involved gland vs unilateral or bilateral mastectomy) did not appear to influence the outcome of the disease, and metastasis to regional lymph nodes did not appear to be a reliable prognostic indicator. 相似文献
107.
F C Battaglia 《Journal of animal science》1992,70(10):3258-3263
Fetal amino acid nutrition and metabolism have been studied primarily in pregnant sheep. The umbilical uptake of amino acids changes during gestation, but at both mid- and late gestation the total supply exceeds that required for growth. Weight-specific protein synthetic rate decreases with increasing gestational age, and these changes are proportional to the changes in metabolic rate. The use of multiple tracer methodology coupled with measurement of net tracer fluxes into and out of fetal and placental tissues can be used to delineate amino acid metabolism in considerable detail. Such studies demonstrate that even essential amino acids can be oxidized extensively by the fetus. The oxidation rate of leucine exceeds its rate of accretion in tissue proteins. Glycine metabolism is unique in several ways; there is a large umbilical uptake of glycine without a measurable uterine uptake. In late gestation there is no significant umbilical uptake of serine, although there is a significant uterine uptake, suggesting net uteroplacental utilization. Glycine is oxidized within the fetal liver and used for serum production. The interorgan exchange of amino acids between the fetal liver and placenta is clearly of major importance for serine and glycine metabolism and is likely to be of major importance for most nonessential amino acids. 相似文献
108.
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
109.
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
110.
Characterization of phosphate species in urban sewage sludges by high-resolution solid-state 31 P NMR
The mineral forms of phosphorus in three urban sewage sludges were characterized using high-resolution solid-state phosphorus-31 nuclear magnetic resonance (NMR) coupled to a sequential extraction. The sludges studied were an anaerobically-digested and heat-treated sludge (Paris-Achères), an activated sludge (Briare) and an anaerobically-digested sludge (Nancy). NMR observations were conducted using both single-pulse and cross-polarization sequences in order to distinguish between 31P nuclei far from 1H nuclei, and 31P located within a fraction of a nanometre of 1H. This approach showed that a complex mixture of P species was present in these sludges. A mixture of hydrogenated octocalcium phosphates and apatites was observed in the three samples. Monetite was present in the anaerobically-digested sludge and brushite in the activated sludge. Dehydrogenated condensed calcium phosphates (compounds with a Ca:P ratio higher than 1.0 such as fluorapatite or tricalcium phosphate) and dehydrogenated pyrophosphates were also probably present in the anaerobically-digested sludge. A poorly-ordered wavellite was observed in the three sludges after the HCl extraction. However, results were inconclusive as to whether this mineral was present in the three sludges, or had been precipitated during the sequential extraction. 相似文献