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271.
Simon R.  Platt  BVM&S  John  Graham  MVB  MSc  Cheryl L.  Chrisman  DVM  MS  Kathleen  Collins  DVM  Sundeep  Chandra  BVSc  PhD  Jeffrey  Sirninger  DVM  Susan M.  Newell  DVM  MS 《Veterinary radiology & ultrasound》1999,40(4):367-371
A 9-year-old male neutered mixed breed dog had a two-month history of progressive left thoracic limb lameness. There was electromyographic evidence of denervation potentials in all muscles of this limb. In magnetic resonance images a multilobulated, hyperintense mass was visible caudal to the middiaphysis of the left humerus on T-2 weighted images. The mass, which was isointense with surrounding tissue on T1 weighted images, extended proximally towards the brachial plexus. The mass was also visible as a fusiform structure of mixed echogenicity sonographically, although fine-needle aspiration performed at this time was nondiagnostic. A malignant peripheral nerve sheath tumor was diagnosed histopathologically.  相似文献   
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Canine hemangiosarcoma (HSA) is an aggressive cancer of endothelial cells with short survival times. Understanding the genomic landscape of HSA may aid in developing therapeutic strategies for dogs and may also inform therapies for the rare and aggressive human cancer angiosarcoma. The objectives of this study were to build a framework for leveraging real-world genomic and clinical data that could provide the foundation for precision medicine in veterinary oncology, and to determine the relationships between genomic and clinical features in canine splenic HSA. One hundred and nine dogs with primary splenic HSA treated by splenectomy that had tumour sequencing via the FidoCure® Precision Medicine Platform targeted sequencing panel were enrolled. Patient signalment, weight, metastasis at diagnosis and overall survival time were retrospectively evaluated. The incidence of genomic alterations in individual genes and their relationship to patient variables including outcome were assessed. Somatic mutations in TP53 (n = 44), NRAS (n = 20) and PIK3CA (n = 19) were most common. Survival was associated with presence of metastases at diagnosis and germline variants in SETD2 and NOTCH1. Age at diagnosis was associated with somatic NRAS mutations and breed. TP53 and PIK3CA somatic mutations were found in larger dogs, while germline SETD2 variants were found in smaller dogs. We identified both somatic mutations and germline variants associated with clinical variables including age, breed and overall survival. These genetic changes may be useful prognostic factors and provide insight into the genomic landscape of hemangiosarcoma.  相似文献   
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Open-ended vasectomies were performed on four male bush dogs (Speothos venaticus), with three having microscopic reversal surgery (vasovasostomy) between 10 and 20 mo post-vasectomy. The key to ease of reversal is leaving the distal (testicular) end open to allow leakage, resulting in a pressure-relieving granuloma. The proximal (abdominal) end is cauterized, providing an effective seal. This technique prevents the buildup of pressure in the epididymis, therefore limiting damage to the male's reproductive capacity. Described here are detailed procedures for both surgeries. One of the three males that underwent vasovasostomy has successfully impregnated his female partner. This study demonstrates that these techniques can be successfully applied to animals. With the two remaining pairs, none of the four individuals were proven breeders prior to the study, so it is not possible to eliminate the possibility of previously existing infertility. This technique may have limited application for carnivores, because vasectomy does not prevent potential adverse effects to females from prolonged, cyclic exposure to endogenous progesterone. In other taxonomic groups (e.g., primates, ungulates, marsupials, and rodents) in which multimale groupings are common, this reversible male sterilization technique could provide managers with the ability to control which males reproduce without eliminating their future reproductive capacity or social interaction.  相似文献   
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