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The host defense competence of uterine-derived polymorphonuclear leukocytes (PMN) from mares considered resistant (grade I uteri) and susceptible (grade III uteri) to chronic endometritis was evaluated for phagocytic and killing (bactericidal) capacities, using a fluorochrome assay. Peripheral blood PMN from noncategorized mares and from grade I and grade III mares were used as controls. Uterine-derived PMN from mares with grade I uteri were functionally competent for phagocytosis and killing of Candida albicans, whereas uterine-derived PMN from mares with grade III uteri had significantly less phagocytic and killing capacities (P greater than or equal to 0.0001). Results of the present study, together with data obtained from chemotactic responsiveness and deformability assays of a previous study, indicated an overall deficiency in the host defense mechanism of uterine-derived PMN from mares with grade III uteri obtained 12 hours after induced Streptococcus zooepidemicus infection. This deficiency may account for the susceptibility of mares with grade III uteri to chronic endometritis.  相似文献   
957.
Moderate to severe ulcerative colitis of the right dorsal colon was diagnosed by necropsy or by exploratory celiotomy and biopsy in 13 horses with a primary clinical complaint of either colic, diarrhea, or weight loss. Clinical signs varied from acute fulminating diarrhea (possibly with fever), colic, dehydration, endotoxic shock and death, to a chronic condition manifested by mild intermittent colic up to several months in duration, and weight loss with or without mild diarrhea. In a large percentage of the horses, those affected had been hypovolemic and received nonsteroidal anti-inflammatory drugs (NSAID) or had received inappropriately high doses of phenylbutazone before the onset of illness. Experimental treatment of two horses with high doses of a phenylbutazone oral paste preparation (6 gm once daily for 5 days) and limitation of their water intake to approximately one half of maintenance requirement (for 5 days) resulted in reproduction of ulcerative colitis involving only the right dorsal colon, which was apparent at necropsy examination 11 and 15 days after initiation of drug use. It was concluded that localized ulcerative lesions in the right dorsal colon may be a previously unreported manifestation of toxicity due to the administration of NSAID.  相似文献   
958.
1. Pineal and neurohypophysial arginine vasotocin (AVT) and mesotocin (MT) were measured in White Leghorn hens, cockerels and castrated males treated with either testosterone propionate (TP) or oestradiol benzoate (EB) (n = 10/group). The lighting regimen was 14 h light: 10 h dark, supplied by natural diffused sunlight and incandescent bulbs. 2. Both AVT and MT were detected in the pineal gland of all the chickens. 3. There was no significant effect of either sex or treatments on pineal MT. 4. Females had about 4 times more pineal AVT than males, regardless of their treatment. There was no effect of the treatments on pineal AVT in the males. 5. No sexual difference in neurohypophysial AVT was detected, but the neurohypophysis of the castrated males treated with EB contained less AVT than the neurohypophysis of the intact males. 6. Intact males had about twice as much MT in the neurohypophysis as females. Castrated males treated with either TP or EB had similar concentrations of neurohypophysial MT, which were lower than that of the intact males, but higher than that of the females.  相似文献   
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A highly purified pilus vaccine prepared from cells of Bacteroides nodosus strain 198 provided a high level of protection against homologous challenge and small, not statistically significant, levels of protection against challenge with 4 other strains each from different serogroups. In a second experiment, a partially purified pilus vaccine from strain 198 induced significant immunity to 1 of 4 heterologous strains which were different from those used in the first experiment. In a third experiment a strain 198 whole cell vaccine produced significant immunity against 3 of 6 heterologous strains used in the first 2 experiments. There was no obvious relationship between the colony type, degree of piliation and level of cross-protection obtained against a particular strain. The results provide further evidence that immunogens associated with, but distinct from, the pilus are involved in cross-protection and that cross-protective antigens are common to some, but not all, strains.  相似文献   
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