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71.
肝脂肪变性病是虹鳟常见的营养缺乏疾病,可使养殖产量罹致重大损失。取虹鳟(Salmo gairdneri)的肝脏和血液进行光学显微镜和电子显微镜观察;血液经常规和生化检验(分析)。石蜡切片病鱼肝细胞大量坏死,结缔组织增生,使肝组织变性破坏,已无法辨认。冰冻切片P.A.S.阴性,空泡中没有脂肪和糖元。电镜扫描与透射观察,病鱼肝细胞坏死,可见大量脂肪滴和空泡。血液常规红血球比数下降,淋巴球数下降,中性白血球和单核球增多。生化指标麝香草酚浊度(TTT)均在2单位以下,麝香草酚絮状(TFT)阴性,谷丙转氨酶(GPT)明显增高;胆固醇下降,血清总蛋白含量下降,白蛋白与球蛋白的比例倒置。  相似文献   
72.
73.
Gross pathological assessment of amoebic gill disease (AGD) is the only non-destructive, financially viable method for rapid and broad-scale disease management of farmed Atlantic salmon, Salmo salar L., in Tasmania. However, given the presumptive nature of this diagnosis, the technique has been considered questionable. This study investigated the degree of conformity between clinical signs and histological lesions observed in a commercial setting. Three groups of Atlantic salmon (n = 42, 100 and 100, respectively) were collected from various farm sites in southern Tasmania between December 2001 and April 2003. Micro-stereoscopic analysis showed that grossly affected tissue regions correspond to areas of hyperplastic lamellar fusion, generally in association with attached Neoparamoeba sp. Agreement between gross signs of AGD and histopathological diagnosis was compared. Kappa analysis indicated moderate to good agreement between methods (kappa = 0.52-0.74). Individual cases of disagreement were further scrutinized and several factors were found to influence the level of agreement between the two methods. Stage of disease development, lesions derived from other pathogens, assessor interpretation/experience, sampling methods, histological technique and/or experience were potential confounding factors. It was concluded that clinical diagnosis is acceptable as a farm-monitoring tool only. Removal of grossly affected tissue and subsequent histological examination is recommended to improve diagnostic accuracy.  相似文献   
74.
Weanling male, Wistar rats (40 per diet) were maintained on 15 diets which provided 4 graded trypsin inhibitor (TI) levels (93, 215, 337, and 577 mg/100g diet) repeated at 3 levels of protein (10%, 20%, and 30%). Raw and heated (toasted) soy flour provided 10% protein in the diet, while casein was added to increase the protein level to 20% and 30%. Three diets containing only casein as the protein source, at 10%, 20%, and 30% were included. Histologic changes occurring in the pancreas were evaluated in approximately 5 rats from each diet at 3 month intervals, beginning at 6 months, for 22 months. Criteria for the diagnosis of the observed histologic changes in the pancreas are discussed. Ultrastructure of the endocrine cells in the gastrointestinal mucosa was also examined.Pancreatic acinar cell density, as determined morphometrically, was reduced throughout the study in rats fed the 577 mg TI/100 g diet, indicating hypertrophy at the cellular level. Nodular hyperplasia was observed in the first sacrifice group at 6 months. Incidence of the lesion was positively related to both time of exposure and level of dietary TI. Acinar adenoma was first observed at 18 months and was most prevalent in rats fed the highest concentration of TI.Endocrine cells of the duodenal mucosa which contain cholecystokinin (so-called I cells) contained a denser population of secretory granules in animals fed the high TI diet compared with I cells from control animals, leading to the speculation that production and secretion of cytoplasmic hormones was increased in TI treated rats.Reference to a company and/or product named by the Department is only for purposes of information and does not imply approval or recommendation of the product to the exclusion of others which may also be suitable.  相似文献   
75.
A dwarf rabbit presented with unilateral aberrant conjunctival growth. Allgoewer’s U-suture therapy was initially used to correct the overgrowth. Centrifugal incisions extending up to the limbus were made on the hypertrophic conjunctiva. Transpalpebral limbal fixation was performed next. When the symptoms recurred 3 weeks later, a second operation was performed using the Lembert suture method instead. The overgrowing membrane was excised radically just posterior to the limbus. The conjunctiva was then sutured using the Lembert pattern. The rabbit recovered with no further complications.  相似文献   
76.
The objective of this study was to investigate muscle fiber growth‐related attributes, especially fiber hyperplasia and hypertrophy, and their relation to growth characteristics in olive flounder. After a conditioning period, juvenile olive flounder (214 g of initial body weight) were weighed after 0, 4, 8, 12, and 24 weeks of a feeding trial and were selected based on mean body weight at each period (G1, G2, G3, G4, and G5, respectively). During the 3.0‐fold increase in body weight (363.1–1,071 g, p < 0.001), the fiber area was increased approximately 2.2 times (p < 0.05), and the median area increased from the G1 to G5 groups (p < 0.05). The G3 group exhibited a greater fiber number than the G2 group (p < 0.05) as the G3 group exhibited a higher percentage of smaller fiber and mosaic hyperplasia. In addition, a higher percentage of centered nuclei and deoxyribonucleic acid amount in the G2 group were accompanied by an increase in fiber number in the G3 group. Therefore, the muscle growth of olive flounder was influenced by continued fiber area growth and a significant number increase by mosaic hyperplasia during a specific period (G2 to G3 groups; from 512.7 to 670.3 g).  相似文献   
77.
2012年山东省青岛市某蛋鸡养殖场中出现病鸡消瘦,产蛋量下降,剖检以肝脏、肺脏、肾脏、胰腺等多处内脏器官出现灰白色肿瘤病灶为特征的病例,经病理组织学检查,瘤组织呈灶性或多中心性,细胞形态较一致,通过内脏型马立克氏病的病理变化鉴别观察,并结合该病例的临床症状,初步诊断为鸡淋巴细胞性白血病,并对本病的防控措施提出了建议。  相似文献   
78.
Morphological and immunohistochemical examinations were carried out on the pancreas of a hyperglycemic 5-year-old male cynomolgus monkey. Body weight gradually decreased from 6 months before termination, accompanying a slight reduction in food consumption and anorexia for the last 2 days. The blood glucose level was markedly elevated when examined at termination. Histopathologically, in the exocrine pancreas, diffuse hyperplasia of centroacinar and intercalated duct cells and diffuse atrophy of acinar cells with sporadic apoptosis were observed, although most centroacinar and intercalated duct cells were proliferating cell nuclear antigen (PCNA)-positive in both the present case and age-matched control animals. In the endocrine pancreas, the islets tended to be hypertrophic, with an increase in insulin-positive cells in comparison with the age-matched control animals. PCNA-positive cells also tended to increase in the islets, although positive cells for phospho-histone H3, a marker for mitotic cells, were not detected in the endocrine and exocrine pancreas. Moreover, neither inflammation nor amyloidosis was noted in the islets. In conclusion, the present case probably suffered from early-stage type 2 diabetes mellitus, and it provides fundamental information concerning pancreatic histopathology under insulin-related derangement in monkeys.  相似文献   
79.
Richter's syndrome (RS) is the development of an aggressive lymphoma in patients with chronic lymphocytic leukaemia (CLL). In humans, RS occurs in 2–20% of CLL, which transform into diffuse large B‐cell lymphoma but reports in dogs are scarce. This study retrospectively describes eight dogs with CLL progressing into RS. A database including 153 dogs with CLL (93T CD8+ and 55 B‐CLL) was interrogated and RS was demonstrated in eight cases (representing 5.2% of total CLL): two with T‐cell (2.2% of T CLL) and six with a B‐cell immunophenotype (10.9% of B‐CLL). When RS occurred, lymphocytes were decreased compared to CLL. Five dogs had anaemia and two dogs thrombocytopenia. Frequent clinical signs included lymph node swelling, coughing, vomiting, neurological signs and weight loss. Independently from the therapy, RS was associated with a short survival (median 41 days). RS should be considered as an unfavourable evolution in canine CLL.  相似文献   
80.
棉铃虫世代种群的发展变化   总被引:3,自引:0,他引:3  
对棉铃虫种群动态的多年研究证明 ,棉铃虫年发生世代从 3.3代增加到 4.5代 ,年平均百株累计卵量增加了 4倍。主害代明显后延多发 ,完全 5代出现率已达 2 2 % ,大发生频率巨增。  相似文献   
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