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261.
A D MacMillan G O Waring W L Spangler A M Roth 《Journal of the American Veterinary Medical Association》1979,175(8):829-832
Bilaterally symmetric opacities were detected in the corneal stroma of 78 (14%) of 560 Siberian Huskies, aged 7 months to 12 years, examined in ophthalmology screening clinics. The opacities were round or horizontally oval and consisted of a diffuse gray homogeneous haze in the anterior stroma or an array of fine polychromatic crystals in the posterior stroma, or both. The corneas were not inflamed. The frequency of occurrence and density of the opacities increased with age. Several affected dogs were closely related, but a specific inheritance pattern could not be established. Light and electron microscopy disclosed clusters of extracellular, thin, needle-shaped, crystalline clefts. Histochemical stains on frozen sections identified neutral fats, phospholipids, and cholesterol as components of the crystals. 相似文献
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Effects of ACTH administration on bovine polymorphonuclear leukocyte function and lymphocyte blastogenesis 总被引:3,自引:0,他引:3
Yearling steers were treated with ACTH to determine the effect of increased plasma cortisol concentration on bovine lymphocyte and polymorphonuclear leukocyte (PMN) function. The administration of ACTH caused a significant (P less than 0.01) increase in serum cortisol concentration and depression of lymphocyte blastogenesis in response to phytohemagglutinin and concanavalin A. The response to pokeweed mitogen was also depressed, but not significantly. Random migration by PMN was significantly enhanced by ACTH treatment, but there was no effect on ingestion of Staphylococcus aureus, nitroblue tetrazolium reduction, or antibody-dependent cell-mediated cytotoxicity by PMN. The iodination reaction, which evaluates the activity of the myeloperoxidase-hydrogen peroxide-halide antibacterial system of the PMN, was significantly impaired after ACTH treatment. These data indicate that specific parameters of lymphocyte and neutrophil function were impaired directly or indirectly by elevated in vivo concentrations of plasma cortisol. 相似文献
266.
Association of increased estradiol and progesterone blood values with altered bovine polymorphonuclear leukocyte function 总被引:4,自引:0,他引:4
J A Roth M L Kaeberle L H Appell R F Nachreiner 《American journal of veterinary research》1983,44(2):247-253
Polymorphonuclear leukocyte (PMN) function and serum concentrations of estradiol, progesterone, and cortisol (hydrocortisone) were monitored concurrently in clinically normal cows during the estrous cycle. Five parameters were used to evaluate PMN function: (i) random migration under agarose, (ii) ingestion of 125I-labeled Staphylococcus aureus, (iii) nitroblue tetrazolium (NBT) reduction, (iv) iodination, and (v) antibody-dependent cell-mediated cytotoxicity. Increased serum estradiol concentrations were associated with enhanced random migration, but had no apparent effect on NBT reduction, iodination, or ingestion of S aureus by bovine PMN. Increased serum estradiol was also associated with increased serum cortisol. Increased serum progesterone values were associated with a depression of NBT reduction and iodination by PMN, but with enhanced random migration and antibody-dependent cell-mediated cytotoxicity. These results indicate that physiologic changes in steroid hormone values during the normal estrous cycle of the cow are associated with alterations in PMN function. 相似文献
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Perioperative Mortality and Long‐Term Survival in 80 Dogs and 32 Cats Undergoing Excision of Thymic Epithelial Tumors 下载免费PDF全文
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Neutrophils isolated from the peripheral blood of pigs free of infection withMycoplasma hyopneumoniae were loaded with a fluorescent indicator (Fura-2) for detection of cytosolic free calcium concentration. The kinetics of the intracellular calcium flux were examined after incubation with or without a pathogenic or a non-pathogenic strain ofM. hyopneumoniae. The basal intracellular calcium concentration was not altered by incubation withM. hyopneumoniae. However, the relative increase in cytoplasmic calcium concentration caused by the addition of opsonized zymosan was significantly (p<0.05) higher in neutrophils incubated withM. hyopneumoniae as compared to neutrophils not incubated withM. hyopneumoniae. Additionally, after zymosan stimulation, the intracellular calcium concentration was greater in neutrophils incubated with a pathogenic strain ofM. hyopneumoniae than in those incubated with a non-pathogenic strain. This suggests thatM. hyopneumoniae alters the signal transduction mechanisms in neutrophils and that this alteration may be related to virulence.Abbreviations [Ca]i
intracellular concentration of calcium
- CCU
colour changing units/ml
- Fura-2/AM
pentaacetoxymethyl ester
- PBS
phosphate-buffered saline, pH 7.2
- TNF
tumour necrosis factor 相似文献
270.
Sserumaga Julius Pyton Kayondo Siraj Ismail Kigozi Abasi Kiggundu Muhammad Namazzi Clementine Walusimbi Kato Bugeza James Molly Allen Mugerwa Swidiq 《Genetic Resources and Crop Evolution》2021,68(7):2997-3010
Genetic Resources and Crop Evolution - Most orphan crops have not been fully sequenced, hence we rely on genome sequences of related species to align markers to different chromosomes. This hinders... 相似文献