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1.
近年对肉鸡腹水综合征的研究已取得进一步的认识 ,在研究肺动脉高压的同时更注意具有潜在作用的心脏病变的研究。家禽的心脏传导系统比较特殊 ,它含有一个返回分支束 ,使右房室瓣受传导神经的支配。当右房室瓣不受传导神经的支配时 ,瓣膜功能不全而引起右心室容量过大 ,可介导右心室肥大。心电图描记是研究肉鸡腹水综合征发病机理的有效手段之一。文章系统地阐述了肉鸡心脏的形态结构和传导系统的特点以及几种肉鸡腹水综合征试验模型的心电图学特征、肉鸡的心脏病理变化与心电图学特征之间的关系 相似文献
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A 7-year-old male Giant Schnauzer was referred with a history of severe vomiting, lethargy, weight loss, polydipsia and polyuria. Detailed investigations revealed leucocytosis with a marked lymphocytosis, mild non-regenerative anaemia, thrombocytopenia, hypercalcaemia and azotaemia. Circulating lymphocytes were small and well-differentiated, and the same lymphoid population was present in bone marrow. Chronic lymphocyctic leukaemia with associated paraneoplastic hypercalcaemia was diagnosed. Immunohistochemical staining of a bone marrow biopsy revealed a neoplastic B-cell line expressing CD79. The dog responded to therapy with prednisolone and chlorambucil for a period of 8 months. 相似文献
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将一日龄艾维因肉仔鸡(雌雄各半)180只在同一舍内饲养,14日龄时将其随机分成4组,其中Ⅰ、Ⅱ组饲料按1%分别添加我们研制的方剂一和方剂二,连续用药15d,为药物预防组;Ⅲ组在饲料中按0.05%添加肾肿腹水消,连用7d(药品要求的预防剂量),为药物对照组;Ⅳ组饲料中不添加任何药物,为空白对照组。Ⅰ-Ⅳ组发病率分别为0、10%、3%和20%,42d时Ⅰ、Ⅳ组体重高于其它组,Ⅰ平均体重为1972.92g,Ⅳ组平均体重为1989.91g。试验表明方剂一为该试验条件下预防肉鸡腹水综合征最有效的方剂,其保护率可达100%,且不影响出栏重。对方剂一预防肉鸡腹水综合征的机理进行探讨。 相似文献
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对虾白斑综合征病毒研究概况 总被引:2,自引:0,他引:2
对虾白斑综合征病毒(WSSV)引起世界范围内养殖对虾的急性、致死性传染病,造成对虾养殖业的巨大损失,在我国这种情况尤为严重。WSSV是同一类紧密相关的无包埋体类杆状病毒,与杆状病毒并无同源性。2001年,中国和荷兰科学家分别报道了WSSV的全基因组DNA序列,启动了WSSV后基因组研究。已有多种检测方法用于WSSV的检测和致病机理的研究。WSSV感染宿主谱广,以多种传播途径感染宿主,目前还没有用于病毒增殖的细胞系,但已有成熟的动物模型,从而方便了对WSSV的研究。本文就该病毒的命名、病毒特性、检测方法、病毒感染增殖、感染宿主、传播途径及感染动物模型等方面的研究现状和进展作一综述。 相似文献
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PULMONARY MINERALIZATION IN FOUR DOGS WITH CUSHING'S SYNDROME 总被引:1,自引:0,他引:1
Clifford R. Berry DVM Norman Ackerman DVM Kevin Monce DVM 《Veterinary radiology & ultrasound》1994,35(1):10-16
The clinical and imaging features of four dogs with Cushing's syndrome and pulmonary mineralization are reviewed. Three dogs presented with a primary complaint of respiratory distress/dyspnea. Three dogs had pituitary dependent Cushing's syndrome, while the remaining one dog had iatrogenic Cushing's syndrome. Each dog had clinical features typical for Cushing's syndrome. Two of the dogs were euthanized due to progressive hypoxemia. In each dog, the serum calcium, phosphorous, blood urea nitrogen and creatinine were normal.
A generalized increase in unstructured interstitial pulmonary opacity with diffuse mineralization was noted on thoracic radiographs of all dogs. In one dog, an ill-defined nodular interstitial pattern of mineralization was present. Delayed bone phase scintigraphy using99m Technetium methylene diphosphonate documented generalized pulmonary uptake in two dogs. 99m Technetium labeled microaggregated albumin lung perfusion scans were normal in these two dogs. 99m Tc-MDP scintigraphy can provide useful information in diagnosing pulmonary mineralization in Cushingoid dogs. 相似文献
A generalized increase in unstructured interstitial pulmonary opacity with diffuse mineralization was noted on thoracic radiographs of all dogs. In one dog, an ill-defined nodular interstitial pattern of mineralization was present. Delayed bone phase scintigraphy using
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To develop an appropriate cryopreservation protocol for spermatophores of black tiger shrimp, Penaeus monodon, three cryoprotectants (dimethyl sulphoxide (DMSO), methanol (MeOH) and ethylene glycol (EG)) at two concentrations (5% and 10%) were examined. Artificial implantation of spermatophores was also carried out to assess the fertilizing ability of fresh and post‐thaw spermatophores. Spermatophores were collected during consecutive regenerations (15‐day intervals) and assessed for qualitative and quantitative changes and also for fertilizing ability by implantation. The mean fertilization rate for artificial insemination using post‐thaw spermatophore was 79.9±3.7%, lower than the fertilization rates observed for artificial implantation using fresh spermatophore and natural mating. Mean hatch rates for fresh spermatophore, frozen‐thawed spermatophore and natural mating were 88.8±0.6%, 87.8±0.4% and 88.3±0.5%, respectively; and there was no difference among the three groups. The mean fertilization rate of spermatophores collected during the first stripping was higher (90.6±0.6) than during the second stripping (85.7±2.6), but the mean hatch rate was not different between the two strippings. The highest mean sperm viability (79.7±0.4%) was obtained from DMSO (5%), with no survival observed in the 10% MeOH treatment. Spermatophore weight, total sperm count and percentage of abnormal sperm were not different between spermatophores collected at the first and second stripping. This is the first study to report high fertilization and hatch rates from cryopreserved spermatophore using artificial implantation of spermatophore before spawning. 相似文献
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Agerholm, J.S., A. Basse and K. Christensen: Investigations on the occurrence of hereditary diseases in the Danish cattle population 1989-1991. Acta vet. scand. 1993, 34, 245-253.– The methods of the Danish Bovine Genetic Disease Programme are outlined, and the results obtained during the first 3 years in function are described. The most common disease reported was spinal muscular atrophy in calves of the Red Danish Dairy breed with 312 reports. Necropsy was performed on 162 cases, and spinal muscular atrophy was diagnosed in 82 of these. Bovine progressive degenerative mye-loencephalopathy, rectovaginal constriction, syndrome of arthrogryposis and palatoschisis, hereditary chondrodysplasia (2 different types), syndactylism, epitheliogenesis imperfecta, and osteogenesis imperfecta was diagnosed with 1 case each. Lethal trait A46 was diagnosed in 4 calves. Some of these diseases have not previously been described in Denmark, and epitheliogenesis imperfecta was for the first time diagnosed in the Hereford breed. Chromosome translocation 1/29 was detected in the Blonde d’Aquitaine (BAQ), Limousine, and Red Danish Dairy breed. The aberration occurred frequently in BAQ. Furthermore, a complex chromosome translocation t(l;8;9)(q45;ql3;q26) was detected in the Red Danish Dairy breed. 相似文献