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51.
Congenital dyserythropoietic anaemia (CDA) is a heterogeneous group of rare genetic disorders that in humans is characterised by ineffective haematopoiesis with morphological abnormalities in erythroid precursor cells and secondary iron overload. In the 1990s, a syndrome of CDA with dyskeratosis and progressive alopecia was reported in Poll Hereford calves in Canada and the USA. We report the clinical and pathological findings in two Poll Hereford calves with this syndrome from separate properties in South Australia. The animals had a variably severe anaemia, associated with abnormal nucleated red blood cells in peripheral blood, and large numbers of rubricytes and metarubricytes with a characteristic nuclear ultrastructure in the bone marrow. Both calves were born with a wiry hair coat and a progressively ‘dirty‐faced’ appearance associated with hyperkeratosis and dyskeratosis (apoptosis).  相似文献   
52.
《Veterinary dermatology》2000,11(3):211-215
In this brief section only three congenital cutaneous diseases are outlined. They include epitheliogenesis imperfecta, epidermolysis bullosa and hyperelastosis cutis. The first is an absence of epidermal structures, the second is a defect at the epidermal–dermal junction and the third is a disease of a component of the dermis. The clinical and histopathologic findings for each are described herein.  相似文献   
53.
AIM:To study the metabolic pathways of adenosine monophosphate (AMP) in the chronic failing cardiac myocytes of patients with congenital heart disease (CHD). METHODS:RESULTS:There was no significant statistic difference among the contents of AMP in three groups (P≥0. 05). The concentration of Ado was lower in the group C (P≤0. 05) and the concentration of IMP was higher significantly (P≤0. 05). There was a significant increase in the ratio of IMP/Ado in the three groups. Negative relationship was found between pre-operative EF of left ventricle and IMP/Ado (K constant). The higher K constant was, the higher incidence of post-operative heart failure would be. CONCLUSION: The metabolic pathway of AMP in the failing cardiac myocytes of CHD may go along with the way to create more IMP. The lower of pre-operative ejection fraction of left ventricle indicates the abnormal change of AMP catabolism, post-operation heart failure may be an important complication in these patients.  相似文献   
54.
A male Holstein-Friesian calf was born with multiple, cauliflower-like, pale pink cutaneous masses on the head and limbs. On histopathological examination, the cutaneous masses were diagnosed as congenital cutaneous fibropapillomatosis. Those lesions involved focal proliferation of sebaceous gland in the dermis. There were no histological findings to suggest bovine papillomavirus infection, such as the presence of intranuclear inclusion bodies, large keratohyalin granules, and koilocytosis. Furthermore, papillomaviral antigens and DNA were not detected by immunohistochemistry and polymerase chain reaction, respectively. These results suggested that there was no association between these cutaneous lesions and bovine papillomavirus infection, and the lesions were considered as harmartomatous changes.  相似文献   
55.
Hamartoma is defined as a benign tumor-like nodule composed of an overgrowth of mature cells and tissues that normally occur in the affected part but with disorganization. Vascular hamartomas are defined as disorganized and excessive proliferations of vascular tissue. Most vascular hamartomas are present at birth or during early infancy and are considered developmental lesions rather than true neoplasms. Vascular hamartomas are rarely described in horses, and reports have been limited to the dorsal carpal region, the ovary, and the face. In this report, we describe a vascular hamartoma arising from the tongue of a 2-year-old Quarter Horse.  相似文献   
56.
Objective To describe the clinical and histological appearance of persistent fetal intraocular vasculature in a colony of ferrets.
Design Prospective study.
Animals studied Eighty-six European ferrets ( Mustela putorius ).
Procedure Both eyes of 76 genetically related progeny and 10 breeding, adult, colony-raised ferrets were studied using a slit lamp biomicroscope and an indirect ophthalmoscope. Ferret progeny were examined after eyelid opening at 5–6 weeks of age, and at 12 months of age. After euthanasia, globes were enucleated and examined histologically.
Results Persistent fetal intraocular vasculature was evident in 21 progeny ferrets at 5–6 weeks of age and in three mature progenitor ferrets. Clinical appearance of diminutive vasculature was characterized by focal remnants of the posterior tunica vasculosa lentis, muscae volitantes, and an occluded hyaloid artery extending from the optic papilla and terminating in the anterior vitreous body. Extensive persistent vasculature was characterized by a perfused hyaloid artery, vasa hyaloidea propria and posterior tunica vasculosa lentis, posterior cortical and capsular cataract, and proliferation of fibrovascular tissue along the posterior lens capsule. Fetal vasculature persisted in 7 of 21 progeny ferrets at one year of age and in three progenitor ferrets. Results of histologic examination showed persistence of the hyaloid vasculature, proliferation of retrolental fibrovascular tissue with osseous metaplasia, posterior capsular and cortical cataract, and occasional retinal detachment.
Conclusions Persistent fetal intraocular vasculature in ferrets appears similar clinically and histologically to persistent fetal intraocular vasculature reported in humans and dogs. The ferret may be a suitable animal model for vasculogenic mechanisms of persistent fetal intraocular vasculature and for evaluating vasoinhibitory growth factors and angiostatic test compounds.  相似文献   
57.
Abstract Congenital cutaneous papillomas were identified in five foals. Age at diagnosis ranged from 305 days' gestation to 2 days of age. Breeds were thoroughbred (2), standard-bred (1), warmblood (1) and paint (1). Two were female, one was male and the gender of two cases was not specified. Masses were pedunculated with a roughened, wart-like (verrucous) or a smoother, cauliflower-like surface. Masses occurred as single lesions on the forelimb, lip and face, or as multiple lesions on the trunk. Histological features included relatively uniform epidermal papillary hyperplasia with variable melanin pigment within basal layers and vacuolization of keratinocytes in all layers, but with no evidence of nuclear or cytoplasmic changes (koilocytes) characteristic of viral infection. One case showed epidermal proliferation with proliferation of pilosebaceous units. Results of immunohistochemical studies for the detection of papillomavirus antigens were negative in all cases. These results suggest that equine congenital papilloma may be a hamartomatous lesion (epidermal nevus) and not a viral-induced growth.  相似文献   
58.
OBJECTIVE: To assess radiologically the caudal vertebrae of a male alpaca with an abnormal tail, and nine of his offspring. PROCEDURE: Right lateral and ventrodorsal radiographs were taken of the caudal vertebrae. RESULTS: The caudal vertebral abnormalities in these alpacas included vertebral subluxation, hemivertebrae, wedge hemivertebrae and block vertebrae. CONCLUSION: These malformations in offspring of one sire suggest a hereditary basis for congenital caudal vertebral malformations in the alpaca.  相似文献   
59.
Three male Poodles (two Toy, one Miniature) were presented to their veterinarians for evaluation of urolithiasis and varying degrees of hepatic encephalopathy. All three dogs were diagnosed as having intrahepatic shunts and referred for surgical correction. In each case, shunts arose from the right branch of the portal vein and were amenable to perivascular dissection caudal to where the vessel entered the hepatic parenchyma and to placement of perivascular cellophane bands to achieve shunt attenuation. During the same period, a female Miniature Poodle also presented for treatment of a congenital portosystemic shunt discovered during evaluation for generalised motor seizures. This animal had an extrahepatic portoazygous shunt that was completely ligated. Congenital portosystemic shunts have not previously been identified in Toy and Miniature Poodles at the University Veterinary Centre, Sydney and the anatomical types of shunt seen in this breed have not previously been reported in a consecutive series of cases. The three male dogs are noteworthy for a number of reasons: all had intrahepatic shunts, despite being small breed dogs; all three presented in a similar fashion, and all had shunts of an anatomical type amenable to placement of cellophane bands. One male dog died within 12 hours of surgery, the remaining three dogs survived and their liver function was normal at follow-up between 2 and 3 months after surgery. Use of cellophane bands for successful attenuation of intrahepatic shunts has not been previously reported.  相似文献   
60.
A German Shepherd Dog presented with recurrent intermandibular and intralingual swelling. Cytological and microbiological findings on fluid aspirated from the mass were consistent with an infected cyst lined by epithelium. The sinus was explored and an epithelium-lined cystic structure was extirpated from the frenulum and body of the tongue. This structure was diagnosed histologically as a dermoid cyst.  相似文献   
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