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81.
动物病理学的研究现状与展望   总被引:1,自引:1,他引:0  
动物病理学是基础兽医学和临床兽医学的桥梁。免疫学和分子生物学等学科的快速发展为动物病理学的发展提供了良好的契机。根据目前动物病理学的现状 ,提出了学科的细化和综合的观点 ,并对该学科的可持续性发展进行了展望  相似文献   
82.
Oral malignant melanoma (OMM) in the dog is often locally aggressive with a high metastatic potential and there are few treatment options that have been demonstrated to improve outcome of this disease. The purpose of this study was to determine whether adjunctive treatment with the Oncept melanoma vaccine affected the outcome of dogs with OMM that had achieved loco‐regional cancer control. Medical records from 45 dogs that presented to the Animal Cancer and Imaging Center were reviewed, including 30 dogs with stage II and III disease. Dogs that received the vaccine did not achieve a greater progression‐free survival, disease‐free interval or median survival time than dogs that did not receive the vaccine.  相似文献   
83.
《African Zoology》2013,48(2):169-178
Lamproglena clariae attaches to gill filaments of Clarias gariepinus, penetrates the gill tissue and consumes blood. Hence, the purpose of this study was to investigate the mechanical damage caused by this parasite on gill filaments of the host. Infestation intensity and haematocrit values of fish blood were determined and correlated. Fish were killed, gills dissected out and observed with a dissection microscope. Gill filaments with adult females in situ were fixed in a solution of alcohol, formaldehyde and acetic acid and preserved in 70% ethanol. Fixed specimens were studied by histological examination following staining with Heidenhein’s azan solution. Gross morphology revealed varying degrees of swelling of gill filaments near the attached specimens of L. clariae. Epithelial hyperplasia, resulting in fusion of gill lamellae and necrosis of the host tissue in the vicinity of the parasite were revealed through histological examination. No correlation was evident between the infestation intensity and fish haematocrit values. Although results showed that L. clariae causes localized infestation, high intensity of infestation may be detrimental to the fish. Hyperplasia of epithelial tissue resulting in fusion of lamellae would result in restriction of air passages and thus hinder the process of respiration of the host.  相似文献   
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85.
A fungus forming black stromata with several immersed ascomata was found associated with living branches of Protium warmingianum (Burseraceae) in the Mata da Biologia, city of Viçosa, Minas Gerais, Brazil. The new species differs from all five species found on literature and is fully described, illustrated and compared with the other species described in the genus. This is the first species of Rosenscheldia found on burseraceae hosts in Brazil and the first species on the host genus Protium.  相似文献   
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87.
【目的】探究两起斑点叉尾鮰Ietalurus punetaus暴发性体表出血溃疡症的发病病因和病理特征。【方法】利用湿片法对鳃组织和体表黏液进行压片,观察寄生虫寄生情况。从发病鱼的肝脏、脾脏和肾脏中分离病原菌,检测细菌感染情况;利用PCR法检测患病斑点叉尾鮰的肝、脾、肾混合组织匀浆中斑点叉尾鮰病毒(Channel catfish virus,CCV)的携带情况。运用组织病理学方法观察病鱼的病理损伤特点,综合分析并推测该病的致病原因。【结果】该出血溃疡症的靶器官主要为脾脏、肾脏、肝胰脏、肠道以及皮肤肌肉。主要表现为严重的血管反应,实质细胞可见肿胀、变性、坏死;而胃、脑和心脏病变较轻,仅有轻微的炎症;鳃丝、眼球和鳔等未见明显病变。所有的患病个体均出现中度至重度出血性坏死性脾炎、中度肾炎、轻度至中度坏死性肝胰腺炎和肠炎。患病斑点叉尾鮰体内未检测到寄生虫、细菌以及CCV。【结论】综合病理学、细菌学和病毒学检测结果,推测此次斑点叉尾鮰暴发性疾病由某种非CCV的病毒感染所致,温度应激可能是引发该病的条件诱因。  相似文献   
88.
Examination of 41 extracted, apically infected mandibular cheek teeth (CT) without obvious causes of infection included radiography, computerised axial tomography and decalcified and undecalcified histology. In CT with recent infections, some pulps remained viable, with proliferative soft and calcified tissue changes confined to the apex. With more advanced CT infections, occlusal pulpar exposure was sometimes present (in 34% of the 41 CT), some infected pulp chambers were filled with necrotic pulp or food, and extensive destructive or proliferative changes were present in the calcified apical tissues.No physical route of infection to the apex was found in 24 CT (59%) that consequently were believed to have anachoretic infections. Fractures involving pulps, including fissure fractures between the clinical crown and infected pulps, were found in eight (20%) CT. Some CT had vertical, full length periodontal destruction between the infected apex and the gingival margin that were believed to be the route of infection in four (19%) CT and dysplastic changes were believed to have caused one (2%) infections.  相似文献   
89.
Osteosarcoma is the most commonly reported bone tumor in dogs, typically affecting the axial and appendicular skeleton. Involvement of the paranasal sinuses and the nasal cavity is extremely rare. This report describes a 6-year-old, female, cross-breed dog presented with signs of 90 days duration and diagnosed with a mass located in the right nasal cavity. Radiography, rhinoscopy, and computed tomography findings suggested the presence of an intranasal tumor. Osteosarcoma in the nasal cavity was diagnosed based on histopathological examination and clinical and imaging findings. Survival time was 12 months from diagnosis.  相似文献   
90.
There is growing evidence that dilated cardiomyopathy may be a major cause of death in captive Livingstone's fruit bats (Pteropus livingstonii). Therefore, the primary aim of this prospective, exploratory study was to examine whether a systematic cardiac ultrasound protocol is feasible in this critically endangered species and to report basic measures of cardiac structure and function from a cohort of apparently healthy bats. A secondary aim was to test the effect posture (dorsal recumbency vs. roosting) has upon cardiac function in this species. Transthoracic echocardiograms, including 2D, Doppler, and tissue Doppler measures of cardiac structure and function were completed as part of routine health examinations for bats at a single center (n = 19). Bats were then grouped by age and disease status and the mean and range data reported for each group. In healthy adult bats, with the exception of a reduction in heart rate (P ≤ 0.05), right atrial systolic area (P ≤ 0.05), and right ventricular velocity during atrial contraction, there were no significant changes in cardiac structure or function in response to the roosting position. However, in the bats presenting with dilated cardiomyopathy the current data suggest that left ventricular ejection fraction is improved while roosting. Further work is required to confirm our initial findings, generate diagnostic reference intervals, and explore the causes of dilated cardiomyopathy in this species.  相似文献   
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