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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
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
52.
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
53.
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
54.
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
55.
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
56.
We compared the results of the ACTH stimulation tests with measurements of alkaline phosphatase and serum cholesterol during Lysodren therapy in 23 dogs with pituitary-dependent hyperadrenocorticism. The ACTH stimulation test proved to be a very sensitive parameter, by which the extent of Lysodren under- or overdosage could be reliably estimated. On the other hand, regulation of the individual Lysodren requirement was not possible by measuring AP and serum cholesterol only. However, it is highly probable that those two parameters can be used to evaluate the general state of metabolism, and they appear to be of prognostic value when greatly elevated. 相似文献
57.
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
58.
This paper reviews the radiological features of 50 canine incisive or maxillary tumours and discusses the value of radiological assessment in the diagnosis and staging of these tumours. The 50 tumours examined included 21 sarcomas, 15 carcinomas, three melanomas and an assortment of benign tumours of the oral cavity. There was not any site specificity for the different histological tumour types within the upper dental arcade, although fibrosarcomas had a tendency to be maxillary whereas the squamous cell carcinomas were equally distributed between the incisive and maxillary regions. Seventy-eight per cent of fibrosarcomas, 82 per cent of squamous cell carcinoma and all three melanomas examined showed radiological evidence of bone involvement. Radiographic changes were also seen in the benign tumours. The pattern of growth of tumours correlated with the radiological changes observed. Malignant tumours showed a tendency to irregular or aggressive bone loss whereas bone production predominated in the benign tumours. 相似文献
59.
Antibody responses to avian encephalomyelitis virus vaccines when administered by different routes 总被引:1,自引:0,他引:1
Antibody responses to a commercial avian encephalomyelitis virus (AEV) vaccine administered by different routes were measured by an enzyme-linked immunosorbent assay (ELISA). Responses to single doses of vaccine administered by the ocular route to 10% of a flock were comparable with those obtained when all birds received a single dose in the drinking water. However, ocular vaccination of 5% of the flock resulted in significantly lower responses than those obtained when 10% were vaccinated. Maternal antibody was shown by the ELISA to persist in chickens from vaccinated flocks for up to 21 days after hatching. Day-old chickens with serum absorbances of < 0.3 at 492 nm, as determined by the ELISA, were shown to be susceptible to intracerebral challenge with the neurotropic Van Roekel strain of AEV. 相似文献
60.