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91.
M E Kehrli K A Weigel A E Freeman J R Thurston D H Kelley 《Veterinary immunology and immunopathology》1991,27(4):303-319
Blood neutrophil functions, lymphocyte blastogenic responses, serum complement, and serum conglutinin activity of 98 lactating Holstein cows from two genetic lines were evaluated. The genetic lines were produced in a selection experiment that created and perpetuated genetic differences in milk production for up to seven generations. No significant differences between the two genetic lines of cows were found for neutrophil function, lymphocyte blastogenic responses, serum complement levels, or serum conglutinin levels. Significant differences between sire progeny groups within lines were found for unstimulated and mitogen-stimulated lymphocyte blastogenesis (P less than 0.0001), and almost all neutrophil functions (antibody independent neutrophil cytotoxicity, antibody dependent neutrophil cytotoxicity, ingestion of bacteria, iodination, chemiluminescence, chemokinesis, and chemotaxis (P less than or equal to 0.05)). Sire progeny group differences (P less than or equal to 0.0001) within lines for serum complement and conglutinin activity were also found. Neutrophil chemiluminescence activity (positive relationship; P less than or equal to 0.001), concanavalin A-stimulated lymphocyte blastogenesis (positive relationship; P less than or equal to 0.004), and serum conglutinin activity levels (negative relationship; P less than or equal to 0.01) each had small but significant associations with the total milk somatic cell count. Cows seropositive for bovine leukosis virus had increased resting and mitogen-stimulated lymphocyte blastogenic activity and were associated with increased in vitro neutrophil random migration and production of superoxide anion. Estimates of genetic parameters of various immune cell functions, of serum complement and of conglutinin levels for daughters of 11 sires with 4-6 daughters in the data set were determined. In this report, genetic variation was demonstrated for nonspecific humoral and cellular immunity. 相似文献
92.
93.
Tim J Evans 《Veterinary Clinics of North America: Equine Practice》2002,18(2):371-8, viii
Ergopeptine alkaloid exposure is common in pregnant mares. Many mares live in geographic areas where Neotyphodium coenophialum-infected tall fescue is the dominant grass in pastures and hay. A variety of grasses and cereal grains can be infected by Claviceps purpurea, and fungal sclerotia can contaminate forage and especially ground and pelleted feed. An understanding of the endocrine alterations associated with ergopeptine alkaloid exposure during pregnancy is necessary for the diagnosis of potential exposure to these compounds and for eective prophylaxis and therapy. 相似文献
94.
Y Maruyama Y Suzuki A Kazusaka S Fujita 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(5):493-497
The intracellular dynamics of norsalsolinol, a neurotoxin candidate causing parkinsonism-like symptoms, in PC12 cells was studied. We found that dopamine and norsalsolinol are co-localized to secretory granule layer by sucrose density gradient in norsalsolinol-treated PC12 cells. The norsalsolinol was actively taken up into isolated secretory vesicle fraction from PC12 cells with a Km value of 41.5+/-6.8 microM. The uptake of 10 microM of norsalsolinol was sensitive to reserpine (1 microM), an inhibitor of vesicular dopamine transporter, and dopamine, an endogenous substrate, but insensitive to GBR-12909, an inhibitor of dopamine transporter on plasma membrane. In norsalsolinol-treated PC12 cells, exposure to high K+ or ATP resulted in simultaneous release of norsalsolinol and dopamine. Time course of a release of dopamine and that of norsalsolinol evoked by 50 mM KCl or 100 microM ATP corresponded to each other. These releases were dependent on the concentrations of secretagogues. These data suggest that norsalsolinol is taken up with dopamine into secretory vesicle via vesicular catecholamine transporter. 相似文献
95.
I.-S. Park G. C. Choi D. S. Kim Y. K. Nam 《Journal of the World Aquaculture Society》2002,33(4):494-500
For the evaluation of hormonal control of spermiation in fish, a method to quanify the spermiation response of mature Rhynchocypris oxycephalus (Sauvage and Dabry) to hormonal therapy is described. Spermatocrit was determined after 7 min centrifugation at 18,000 ± g and sperm density was estimated by a standard hemocytomer method. Sperm density can be predicted from spermatocrit since their relationship is linear as described by the regression equation, Y = 3.68X - 27.18 ( R 2 = 0.82, N = 50). where Y is spermatocrit and × is sperm density. Milt production by mature R. oxycephalus was highest at 24 h after injection of 1,000 IU human chorionic gonadotropin (HCG) and 50 μg luteinizing hormone-releasing hormone analogue (LHRHa) per kg body weight. Increased milt production coincided with low spermatocrit and sperm density levels. These results demonstrate that spermiation in mature R. oxycephalus can be reliably evaluated by a spermatocrit method and that HCG and LHRHa are effective in stimulating of spermiation in this species. 相似文献
96.
Seven cases of cutaneous hemangioma and nine of cutaneous hemangiosarcoma were diagnosed from biopsy specimens of 15 Domestic Shorthairs of 5,091 cats that were examined by necropsy or biopsy during the 5-year period from 1 January 1986 through 31 December 1990. All but three cats were male. Tumor cells of both hemangiomas and hemangiosarcomas were immunoreactive for factor VIII-related antigen and for vimentin by the avidin biotin peroxidase complex method. In cats with a median age of 10 years, hemangiomas occurred in skin with pigmented hair in six of seven cases without apparent site predilection. These solitary tumors did not recur after excision although one cat (No. 3) subsequently developed cutaneous hemangiosarcoma at another site. Seven of nine hemangiosarcomas occurred in dermis and subcutis of the head, usually on the pinna. All five hemangiosarcomas of the head, for which cutaneous pigmentation could be determined, occurred in unpigmented skin. Cats with hemangiosarcoma had a median age of 12.5 years at the time of diagnosis. Metastasis has not been documented, but hemangiosarcoma has recurred, from 1 month to 2 years after excision, in 6/7 cats that were studied. 相似文献
97.
J Kimura A Tsukise M Okano 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(5):1035-1037
The dependency of the secretory function of the feline major vestibular gland (Bartholin's gland) on the ovarian steroid hormones was studied histochemically. After estrogen (estradiol-17 beta or diethylstilbestrol), progesterone or a combination of these was administered to cats which were previously ovariohysterectomized, the major vestibular glands were removed, embedded in paraffin, sectioned, and stained by alcian blue, periodic acid-Schiff or peroxidase-labeled lectin (peanut agglutinin and wheat germ agglutinin). The vividly positive reactions to the stainings applied were observed in the secretory epithelial cells of the major vestibular glands in the estrogen treated animals. The dependency of the secretory function of the major vestibular glands on the estrogen was demonstrated in this study. 相似文献
98.
S Agungpriyono Y Yamamoto N Kitamura J Yamada K Sigit T Yamashita 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(6):1063-1069
The stomach of the lesser mouse deer (Tragulus javanicus) was observed macroscopically. It consisted of only three compartments, rumen, reticulum and abomasum without omasum. The rumen was S-shaped with large ventral and caudoventral blind sacs and the reticulum was larger than the abomasum. Internally, the rumen was covered with numerous ruminal papillae even on the pillars and the ruminoreticular fold. These papillae were leaf- or tongue-like shaped and varied in size and density. The reticulum had honey-combed crests and the secondary crests were found rarely. The lips of the reticular groove were prominent and more developed in the aboral part than in the oral one. A sac-like transition zone, which had more prominent mucosal folds than had the floor of the reticular groove, was observed between the caudal end of the reticular groove and the abomasum. Mucosal folds of the abomasum were spiral, low but rather thick. These findings were discussed in view of comparison with other ruminants and of possible functional implications. 相似文献
99.
A field experiment was conducted with different nitrogen regimes to assess the growth and yield performance of wheat genotypes which differ in nitrate assimilation potential. Genotypic differences in biomass accumulation were observed at different growth stages. The nitrogen treatment had little effect on biomass accumulation at early stages of growth, while at later stages of growth there was enhanced biomass accumulation when N was applied in more than two splits. On an average, genotypes with high nitrate reductase activity (the 'HNR' genotypes) accumulated 14.2 % more biomass than the genotypes with low nitrate reductase activity ('LNR' genotypes) when an extra dose (40 kg N ha−1 ) of nitrogen was given at the time of anthesis. The application of nitrogen in more than two splits increased grain yield of both 'HNR' and 'LNR' genotypes mainly by increasing grain weight per ear. The application of an extra dose of nitrogen (40 kg N ha−1 ) at the time of anthesis increased grain yield of 'HNR' genotypes by 38.5 % as compared to 'LNR' genotypes. 相似文献
100.
This study describes the epidemiological features of bovine spongiform encephalopathy (BSE) in Northern Ireland where the first case occurred in November 1988. They were very similar to those observed in Great Britain except that the annual incidence of BSE in 1990 in Northern Ireland, 2.3 confirmed cases per 10,000 adult cows, was approximately one 10th of that in Great Britain. The findings were also consistent with the current hypothesis that affected cattle had been exposed to a scrapie-like agent via cattle feedstuffs containing ruminant-derived protein. However, a preliminary investigation of the potential sources of infection for cattle in Northern Ireland did not provide any conclusive evidence. 相似文献