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41.
Ji-tao CHANG De-bin YU Jian-bin LIANG Jia CHEN Jian-fa WANG Fang WANG Zhi-gang JIANG Xi-jun HE Rui WU Li YU 《农业科学学报》2019,18(1):160-168
Twelve quarters of six lactating cows were inoculated with Mycoplasma leachii strain GN407 through intramammary ductal infusion; another 12 quarters were inoculated with heat-inactivated M. leachii culture medium as negative controls. Multidisciplinary procedures, including clinical assessment, etiology assessment, pathology and immunohistochemistry (IHC), were used to elucidate the pathogenicity of M. leachii in bovine mastitis. From post-inoculation days (PIDs) 3 to 9, 12 inoculated quarters developed mild to severe clinical mastitis and mammary tissue histopathological changes, including inflammatory cell infiltration and architectural destruction of mammary gland ducts. The M. leachii antigen was also detected by IHC in the mammary gland epithelial cells of the inoculated quarters as a weak signal on PID 6 and as a strong signal on PID 9. The control quarters also developed mild mastitis and histopathological changes on PID 9, and M. leachii was also detected by IHC. Throughout the experimental period, the quarters of the negative control cow were clinically and pathologically normal, and the M. leachii antigen was not detected. In conclusion, direct histological and immunohistochemical evidence confirmed that M. leachii causes clinical bovine mastitis through histopathological lesions induced by invasion of the pathogen into mammary gland cells and through inflammatory cell infiltration. 相似文献
42.
收集北京地区2015~2016年宠物医院的部分宠物犬肿瘤病例56例,采用组织病理学方法进行病理诊断,并对患病动物的品种、发生部位、年龄和性别与肿瘤发生关系进行了统计分析。结果发现,56个病例中有44例确诊为肿瘤,其中良性肿瘤21例,包括肛周腺瘤、皮脂腺瘤和肥大细胞瘤等;恶性肿瘤23例,包括乳腺癌、鳞状上皮细胞癌和肛周腺癌等。本次采集的病例中,大型犬与小型犬发病率持平,皮肤、肛周与乳腺部位肿瘤的发生率较高;7岁以后是肿瘤高发期;雌性犬皮肤和乳腺肿瘤的患病率高于雄性,雄性宠物犬肛周腺肿瘤的发生率高于雌性,肿瘤总患病率雄性与雌性持平。本研究为今后宠物犬肿瘤的流行病学及诊断提供了新的参考资料。 相似文献
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44.
Marina L. Leis M. Elyse Salpeter Bianca S. Bauer Dale L. Godson Bruce H. Grahn 《Veterinary ophthalmology》2017,20(4):365-371
A 15‐year‐old, neutered male, Shih Tzu cross developed progressive corneal stromal thickening and vascularization of the right eye, and 5 months later, of the left eye. Both eyes became blind due to extensive corneal opacification and were enucleated. Light microscopic examination revealed a diffuse corneal infiltrate of neoplastic mesenchymal cells, and immunohistochemistry revealed diffuse cytoplasmic vimentin immunoreactivity and variable cytoplasmic and nuclear immunoreactivity for S100 in the neoplastic cells. Transmission electron microscopy revealed desmosomes between contiguous cells, thread‐like cytoplasmic processes coated with basement membrane, extracellular bundles of collagen, and axonal degeneration consistent with features of a nerve sheath neoplasm. This is the first report of primary, bilateral corneal nerve sheath sarcoma in a canine. 相似文献
45.
In veterinary oncologic specimens, histopathology is the gold standard for determining adequacy of excision. Despite limitations of this technique, the pathologist's interpretation of margin status significantly impacts patient management, including indications for adjuvant therapy. This article aims to summarize peer‐reviewed literature as it relates to histologic margin evaluation in veterinary cancer patients. The value of histologic tumour‐free margins and technical factors influencing histopathologic margin outcomes are also discussed. We review alternative strategies for determining excisional status, and discuss how an evolving understanding of tumour biology might inform clinical and research perspectives on surgical margins. In doing so, we aim to provide context and a stimulus for future investigations into this important yet incompletely understood topic. 相似文献
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47.
利用美国分析化学家协会(Association of Official Analytical Chemists, AOAC)所推荐的小鼠生物法(mouse bioassay, MBA), 测定了塔玛亚历山大藻(Alexandrium tamarense)(ATHK藻株)毒素粗提液的麻痹性贝毒(paralytic shellfish poisoning, PSP)毒性;采用浸浴方式, 研究了该藻株对中国对虾的急性毒性; 采用HE染色方法, 分别对有毒藻浸浴处理和毒素粗提液注射处理后96 h中国对虾(Fenneropenaeus chinensis)的鳃和肝胰腺石蜡切片进行观察。结果表明, 该藻株麻痹性贝毒毒性为3.9×10–5 MU/cell (相当于7.3 pg STX Equal/cell), 在同种藻株中属低毒藻株; 在96 h急性毒性实验中, 塔玛亚历山大藻对中国对虾的半致死浓度(LC50)为1.0×104 cells/mL, 安全浓度(SC)为1.0×103 cells/mL; 石蜡切片观察发现, 塔玛亚历山大藻与毒素粗提液分别引起了鳃和肝胰腺组织出现细胞肿胀、空泡化等病理变化。以上研究结果提示, 塔玛亚历山大藻对中国对虾有急性致死作用。为了保证中国对虾的健康养殖, 养殖水体中的塔玛亚历山大藻浓度至少应该控制在1.0×103 cells/mL以下; 鳃的病变直接导致对虾窒息死亡可能是塔玛亚历山大藻暴露后对虾急性致死作用的最重要原因;塔玛亚历山大藻所产的PSP毒素可引起虾体代谢和解毒的主要器官—肝胰腺的病变。 相似文献
48.
西伯利亚鲟桑葚心病理组织学和病因的初步研究 总被引:1,自引:1,他引:0
为了对心脏囊肿状病变的西伯利亚鲟进行病理组织学观察和病因初步探讨,使用病理组织学和电镜观察技术,对患病西伯利亚鲟各器官进行组织病理学观察。结果表明,患病西伯利亚鲟心脏表面可观察到米粒大、息肉状、紫褐色的囊状肿物,似桑葚状,心外膜上皮细胞和结缔组织明显增生,形成囊肿。组织病变为心外膜囊肿,呈动态发展过程,主要表现为囊肿上皮由扁平变为立方上皮;囊肿壁逐渐增厚与分化,使囊腔不断增多变大,腔内有大量未分化的圆球形、梭形等不同成熟度的血细胞,形成血管组织,并浸润着大量游离或团状分布细胞,整个病变类似一种肿瘤型的恶性增生,心肌细胞肿胀,断裂,溶解,坏死;肝细胞脂肪变性并浸润炎性细胞;肾间质和脾脏淋巴细胞增多。鳃小片之间观察到大量细菌侵袭上皮细胞;鳃小片上皮细胞严重肿胀增生。电子显微镜观察到心脏、肝脏、脾脏和肾脏中有大量细菌;该病可能与微量元素有关,所观察到的细菌不是直接病因。本实验对西伯利亚鲟桑葚心病的组织病理变化进行了较为系统的研究,为进一步查明病因、临床诊断防治和致病机理等相关研究提供基础资料。 相似文献
49.
During 2005 and 2010, a survey of edwardsiellosis on eight turbot, Scophthalmus maximus (L.), farms was conducted in China. This report presents the detailed results of the study on this disease. Diseased turbot displayed two distinct types of gross signs: black discoloration of the dorsal skin on the posterior portion of the body; and red cutaneous foci on the ventral side. Internally, the most pronounced clinical signs in all fish examined were enlarged kidneys. The causal agent of the disease was finally proved to be one species of bacterium that was identified as Edwardsiella tarda by physiological and biochemical tests, API 32E and 16S ribosomal RNA sequence analysis. It is noteworthy that unlike the commonly described E. tarda strains, the isolates in this study were non‐motile strains without flagella. A histopathological study revealed that E. tarda infection was systemic in turbot and that kidney showed the most significant pathological changes, including acute focal necrosis, an influx of macrophages and formation of granuloma. The most common histopathological characteristics of this disease are the proliferation of macrophage in various organs and formation of granuloma. In addition, this article also gave background information on the disease and presented the results of virulence tests with the E. tarda strain identified in this study. 相似文献
50.
【目的】建立大鼠子宫内膜炎模型,为子宫内膜炎的发病机理及其预防治疗研究提供合适的动物病理模型。【方法】将30只清洁级雌性大鼠随机分为感染组(22只)和对照组(8只),采用手术法给大鼠子宫腔内感染致病性大肠埃希菌、金黄色葡萄球菌、无乳链球菌(菌液体积比为2∶1∶1)的混合菌液,对照组大鼠未感染致病菌的混合菌液。分别于感染后第3,6,9,12天剖杀大鼠,检测其大体剖检病变和组织病理学变化,计算子宫指数,并对子宫内容物病原菌进行分离鉴定。【结果】感染后3~12 d,感染组大鼠子宫指数均较对照组大鼠极显著增加(P0.01),感染大鼠子宫出现急性卡他性炎症(感染后第3天和第6天)、化脓性炎症(感染后第9天)和慢性增生性炎症(感染后第12天);感染前期可见子宫内膜上皮细胞脱落,黏膜层水肿、充血、出血,炎症细胞浸润;感染后期可见肌层增厚等病变。【结论】采用手术法成功建立了大鼠子宫内膜炎模型,且感染后第3天为造模成功的最佳时间。 相似文献