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1.
A large, firm, multi-cystic mammary gland mass grew slowly over 4 y in a 12-y-old, female Finn–Shetland cross sheep. A diagnosis of epithelial malignancy was suspected following fine-needle aspiration cytology at 30 mo after initial observation. The sheep was euthanized when the flock was downsized 18 mo later. A field postmortem examination revealed a large mammary mass, but an absence of metastases to internal organs. Imprint cytology of the mammary tissue supported a benign proliferative process. Histologically, mammary tissue was obliterated by cystic, tubular, and papillary adenomatous arrangements of mammary epithelium, with an anaplastic component, consistent with mammary carcinoma arising in an adenoma. IHC showed strong nuclear positivity to the antibody against progesterone receptor and minimal positivity to the antibody against estrogen receptor alpha expression. Intrinsic subtyping for basal or luminal epithelial origin was attempted through adaptation of companion animal IHC classification panels; high- and low-molecular-weight cytokeratins (CK5, CK8, CK18) failed to stain, but p63 expression for basal epithelium was positive.  相似文献   
2.
Thymoma is a rare condition in horses. This case of a 24-year-old Warmblood gelding that was presented with oedema and signs of vascular congestion of the left forelimb caused by a thoracic mass is described. The diagnostic work-up included blood chemistry, cytology of pleural effusion, ultrasonography, radiography and the visualisation and collection of a tissue sample by thoracoscopy. Finally, post-mortem findings and histopathology revealed thymic epithelial neoplasia with histomorphologic features previously unreported in horses. The unique mixture of spindle-shaped and epithelioid tumour cells in combination with clear features of malignancy suggested the application of the Moran and Suster histological classification system for thymomas in humans (Moran and Suster, 2008, Curr. Treat. Options Oncol., 9, 288), which has not been reported in an equine case before and fits well to the present case.  相似文献   
3.
ABSTRACT: To clarify the quantitative changes in the transport of orally intubated protein into the blood circulation as macromolecules in development, immunoglobulin Y (IgY) extracted from chicken eggs was administered orally to juvenile Japanese eel, Anguilla japonica . For the first experiment, which was performed before the commencement of artificial feeding, the oral delivery of 2.0 μg/0.1 g bodyweight of IgY resulted in a rapid increase in plasma IgY to a maximum of 2.30 μg/mL. However, the transport of IgY into the blood decreased significantly in the experiments that followed, which were performed after 12, 25 and 42 days. During this period, bodyweight increased approximately by a factor of eight, and rapid growth of the stomach was observed histologically. Possible contributions for the development of the alimentary canal to the diminishment of intestinal protein assimilation are discussed.  相似文献   
4.
The bioavailability of three formulations of ivermectin was determined following oral administration to dogs. The average peak plasma level (C max) of ivermectin administered in the standard tablet formulation at 6 and 100 µg/kg of body weight was 2.97 and 44.31 ng/g, respectively. This suggest dose-dependent pharmacokinetics.C max and total ivermectin bioavailability, as assessed from the area under the plasma curve (AUC), were similar between two tablet formulations of ivermectin administered at 100 µg/kg. Furthermore,C max was similar following administration of radiolabelled ivermectin at 6 µg/kg in either a beef-based chewable formulation or in the standard tablet formulation.  相似文献   
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Diseases caused by lymphoid leukosis virus (LLV), a retrovirus, take a long time after infection to develop and have a wide variety of pathological manifestations. This long latent period is characteristic of persistent virus infections. Disease produced by LLV infection and its underlying mechanisms is compared with persistent infections caused by other retroviruses in birds and mammals of veterinary importance. The diseases considered for comparison are those caused by reticuloendotheliosis, feline leukaemia, bovine leukosis and equine infectious anaemia viruses. There are significant changes in the immunological status in all diseases caused by these viruses. LLV infections follow this trend with, in manifestations of neoplastic disease, a perturbation of the normal switch that occurs from IgM to IgG synthesis. There are also indications of other immunological disturbances.Factors other than immunological disturbances may contribute to the length of time after infection required for the many forms of LLV infection to appear. Such additional factors may include the operation of biological clocks, such as the arrival of sexual maturity, and also the very nature of retroviruses. These factors, like the immunological changes, play major roles in the maintenance and progression of persistent retrovirus infections.Abbreviations ACTH adrenocorticotropic hormone - AEV avian erythroblastosis virus - AMV avian myeloblastosis virus - BLV bovine leukaemia virus - CAV chicken anaemia virus - EBL enzootic bovine leukaemia - EIAV equine infectious anaemia virus - env envelope gene - FeLV feline leukaemia virus - FeSV feline sarcoma virus - FOCMA feline oncovirus membrane-associated antigen; gag, group antigen gene - HTLV human T-cell leukaemia virus - LLV lymphoid leukosis virus - L/S leukosis/sarcoma - LTR long terminal repeat - MAV myeloblastosis-associated virus - MDV Marek disease virus - MuLV mouse leukaemia virus - ORF open reading frame; pol, polymerase gene - REV reticuloendotheliosis virus - RIF resistance-inducing factor - RSV Rous sarcoma virus  相似文献   
7.
A retrospective study was undertaken of dogs presented to the Animal Health Trust for treatment of oral malignant melanoma, without radiographic evidence of pulmonary metastases. Group 1 (n = 13) received radiotherapy of the primary and any lymph node metastases (4 weekly fractions of 9 Gy); and group 2 (n = 15) were treated the same but additionally received between two and six doses carboplatin at 300 mg m?2 every 3 weeks. Median survival times for the two groups were 307 and 286 days, respectively (P > 0.05). In addition, carboplatin therapy did not significantly reduce the proportion of dogs dying due to metastases (three from group 1 and four from group 2). We found no evidence of a beneficial effect of carboplatin therapy over radiotherapy alone.  相似文献   
8.
AIM: To examine the expression and distribution of tumor necrosis factor-α (TNF-α), tumor necrosis factor receptor I (TNFR I) and apoptosis in oral lichen planus, and evaluate their roles and relation in the oral lichen. METHODS: Immunohistochemical technique and TUNEL were employed to study the expression of TNF-α, TNFR I and apoptosis in 50 cases of oral lichen planus and 10 normal oral mucosa specimens. RESULTS: Compared with the normal control group, TNF-α expression was upregulated in mononuclear cells in lamina propria and decreased in keratinocytes in oral lichen planus lesion (P<0.05). On the contrary, TNFR I expression was increased in keratinocytes and decreased in lamina propria in oral lichen planus lesion (P<0.05). The increased apoptosis index in keratinocytes and the decreased apoptosis index in lamina propria were found in oral lichen planus (P<0.05). CONCLUSION: The accelerated apoptosis of keratinocytes and the inhibition of lymphocytes apoptosis may contribute to the formation and progression of oral lichen planus.  相似文献   
9.
中华鳖对温和气单胞菌口服微球缓释疫苗的免疫应答   总被引:3,自引:0,他引:3  
以中华鳖温和气单胞菌 (Aeromonas sobria,As) Z- 1株灭活全菌液 ,采用生物降解性高分子材料制成缓释微球疫苗 ,口服免疫中华鳖 ,测定血清中凝集抗体、血液中白细胞杀菌率以及对活菌攻击的免疫保护率。结果表明 ,中华鳖口服微球疫苗 ,其血清中凝集抗体效价和血液中白细胞杀菌百分率均可达到灭活菌液注射组相当的水平 (P>0 .0 5 ) ,显著高于对照组 (P<0 .0 1) ;微球疫苗口服组和灭活菌液注射组的免疫保护率分别为 94 .7%和 89.5 % ,两者差异不显著 (P>0 .0 5 ) ,而对照组小鼠 95 %死亡。采用可生物降解微球作为中华鳖气单胞菌口服疫苗的载体系统是可行的。  相似文献   
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