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91.
An 11-year-old thoroughbred gelding was euthanatized because of right nasal cavity tumor. The tumor consisted of round to oval cells with a scanty cytoplasm and hyperchromatic nuclei. Homer-Wright rosettes and pseudorosettes, as well as microcysts were seen. Neoplastic cells were immunoreactive to vimentin, S-100 protein, and neuron-specific enolase, glial fibrillary acidic protein and microtube-associated protein in varying degrees, indicating neurogenic nature. Based on these findings, this tumor was diagnosed as an olfactory neuroblastoma. Since this type is an uncommon tumor showing histological variety, the nature is discussed.  相似文献   
92.
93.
Acetylcholinesterase (AChE) histochemistry and quantitative analysis were used to investigate and compare the projections and densities of cerebral perivascular AChE nerves in five avian species. In the society finch, AChE nerves arising from the cerebral carotid, internal ethmoidal and vertebral arteries generally have no overlap with each other. This is different from AChE neuronal projections via these three vascular routes reported previously for the pigeon, duck, chicken and quail. AChE nerves supplying the pigeon cerebral arterial tree are the highest in density, predominate in the anterior circulation (AC) rather than in the posterior circulation (PC). Similar differential supply of nerves is also found in the duck, with a marked low density in the PC. In contrast, the chicken PC has a substantial amount of AChE nerves that is larger than the fiber amount contained in the AC. The reduction of nerves is far greater in both the AC and PC of the finch. It is not so prominent as that seen in the quail. The significant difference in the distribution and density of cerebral perivascular AChE nerves presented here may indicate that there are some species-specific cholinergic controlling mechanisms responsible for the cerebral circulation of birds.  相似文献   
94.
This experiment was designed to investigate the effects of different concentrations of cellobiose (CB) or a twin strain of Saccharomyces cerevisiae live cells (YST) (20, 40 and 60 mg/60 mL), and CB + YST (60 + 20, 60 + 40, 60 + 60 mg/60 mL) on mixed ruminal microorganism fermentation in vitro. Ruminal fluid was collected from a cow, mixed with phosphate buffer (1:2) and incubated (60 mL) anaerobically at 38°C for 24 h with or without supplement plus 400 mg (dry matter [DM] basis) substrate (hay plus concentrate, 1.5:1). The medium pH numerically decreased with CB and CB + YST, but was unchanged with YST. The total volatile fatty acid and proportion of propionate increased (P < 0.05) in all cases. The proportion of acetate decreased (P < 0.05) with CB and CB + YST, but increased (P < 0.05) with YST and that of butyrate increased (P < 0.05) with CB and CB + YST, but decreased (P < 0.05) with YST. Ammonia‐N decreased (P < 0.05) with CB and CB + YST, but was unchanged with YST. The number of protozoa was unchanged, and that of cellulolytic bacteria increased (P < 0.05) in all cases. Total gas production increased (P < 0.05) in all cases. Methane decreased, hydrogen was unchanged by YST and both gases were unchanged by CB and CB + YST. The in vitro disappearance of DM and neutral detergent fiber increased (P < 0.05) by 11.2% and 8.9%, 9% and 8.5%, and 12.1% and 10.2% in the case of CB, YST and CB + YST, respectively. Therefore, the dietary supplementation of CB and/or YST may improve ruminal fermentation and digestibility.  相似文献   
95.
Rhabdoid tumor is a highly aggressive neoplasm of unknown cellular origin in humans, usually occurring in the kidney and central nervous system of infants or children. In older patients, it occurs rarely in other organs, including the skin and soft tissues. A subcutaneous mass in a 13-year-old male mixed-breed cat was composed of nests or sheets of round to polygonal cells with glassy eosinophilic cytoplasmic inclusions. Immunohistochemically, many neoplastic cells expressed vimentin, localized to the cytoplasmic inclusions, whereas the cytoplasm of some neoplastic cells was diffusely positive for neuron-specific enolase, neurofilament, or S-100 protein. By electron microscopy, the cytoplasmic inclusions were found to be composed of aggregates of intermediate filaments. These findings are quite similar to the histologic, immunohistochemical, and ultrastructural features of human rhabdoid tumors and the few rhabdoid tumors reported in animals.  相似文献   
96.
97.
A neoplastic nodular lesion consisting of an admixture of granular cell tumor and adenocarcinoma was found in the uterus of a 26-month-old Djungarian hamster. Neoplastic cells of the uterine adenocarcinoma showed an epithelial nature in their growth patterns and by cytokeratin-immunopositive reaction, exhibiting nuclear pleomorphism. The granular cells had an abundant amount of fine granular eosinophilic cytoplasm and eccentric or central nuclei with no nuclear atypia; the granular structures were positive for periodic acid-Schiff with diastase resistance and were confirmed as lysosomes/autophagosomes by electron microscopy; immunohistochemically, the cells reacted to desmin, vimentin and α-smooth muscle actin and negatively for neurogenic, histiocyte/macrophage or epithelial markers, indicating smooth muscle origin. Because these tumors were generated from different cell origins, a diagnosis of collision tumor was made.  相似文献   
98.
RPLM对泌乳后期奶牛血液代谢物、产乳量和乳成分的影响   总被引:1,自引:0,他引:1  
选用 8头经产荷斯坦种乳牛 ,分为对照和瘤胃保护赖氨酸 蛋氨酸 (RPLM )组 ,以二乘反转法 ,研究了RPLM对泌乳后期奶牛瘤胃发酵、血液指标、产乳量和乳成分的影响。对照日粮中添加 10 0 g/d保护材料 ,RPLM组日粮中添加 10 0g/d含Lys 11 6g、Met 4 7g的保护制品。RPLM组与对照组比较 ,血浆游离Lys、Met浓度略有增加 (P >0 1) ,血浆葡萄糖浓度有增加趋势 (P <0 1) ,干物质采食量无明显变化 ,乳量和 4%的标准乳量分别增加 0 5kg/d(2 2 %)和 0 8kg/d(3 5 %) ,乳蛋白率、乳脂率和乳糖率均略高于对照组 (0 0 1%0 0 6%) ,乳蛋白质和乳脂肪生产量分别增加 2 0g/d和 40 g/d ,饲料蛋白质转化为乳蛋白质的效率提高5 9%,但均无明显差异 (P >0 1)。以上结果表明 :泌乳后期奶牛日粮中添加瘤胃保护赖氨酸和蛋氨酸 ,没有明显地提高产乳量和改善乳成分的效果。  相似文献   
99.
ABSTRACT:   A C-type lectin (BRA-2) isolated from the acorn barnacle Megabalanus rosa , which was a glycoprotein having an N -linked sugar chain, was deglycosylated by N -glycopeptidase F. The structure of the released sugar chains was determined by a 2-D mapping method after derivatization with a fluorescent reagent, 2-aminopyridine, to be Manα1-6(Manα1-3)Manβ1-4GlcNAcβ1-4(Fucα1-6)GlcNAc and Manα1-6(GlcNAcβ1-2Manα1-3)Manβ1-4GlcNAcβ1-4(Fucα1-6)GlcNAc. The structures were confirmed by matrix-assisted laser desorption ionization mass spectrometry and a comparison with authentic sugar chains by high-pressure liquid chromatography. Various properties of BRA-2 were examined before and after deglycosylation. The susceptibility of BRA-2 to protease digestion was increased by deglycosylation. However, the inhibitory activity toward calcium carbonate crystallization as well as the hemagglutinating activity of deglycosylated BRA-2 was significantly decreased. These results suggest that the sugar chains of BRA-2 are important to both its structural stability and its function.  相似文献   
100.
Antibody against Aeromonas salmonicida was detected in sera from immunised or experimentally infected rainbow trout by enzyme-linked immunosorbent assay (ELISA) using the biotin-avidin system. The ELISA titre correlated well with the agglutinin titres of the sera, but the ELISA was found to be more sensitive than the agglutination test. When the rainbow trout serum was separated by column chromatography, antibody activity (determined by ELISA and agglutination test) was detected in the IgM fractions. Minimum cross reaction was observed in the ELISA system between antigen prepared from A salmonicida and antibodies against Vibrio species and other species of Aeromonas. The specificity of the ELISA was also confirmed by inhibition test. Immunisation of rainbow trout with a virulent strain of A salmonicida provided good protection, though no correlation was observed between the protection and the ELISA titres of sera.  相似文献   
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