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81.
A 15-year-old Sports horse gelding was referred for nonweightbearing lameness of the left hindlimb. Septic cellulitis was diagnosed and managed medically. After 14 days, septic tenosynovitis of the digital flexor tendon sheath (DFTS), with septic tendinitis of the superficial (SDFT) and deep (DDFT) digital flexor tendons, became evident. Surgical resection of the intrathecal portion of the septic SDFT was performed. Post-operatively, a half-limb cast was placed on the operated limb for 10 weeks followed by an articulated orthotic support boot during a rehabilitation period of 6 weeks. The horse recovered and regained long-term pasture soundness. Ultrasonography demonstrated the presence of bridging connective tissue in the location of the resected SDFT.  相似文献   
82.
A cerebrospinal fluid sample collected from the cerebellomedullary cistern of a 10-year-old Shetland Sheepdog with a recent history of seizures was submitted for fluid analysis and cytologic examination. Key findings included a total nucleated cell count of 520/microL (reference interval 0-5 cells/microL), with a predominance of mononuclear cells, a protein concentration of 51.8 mg/dL (reference interval 0-35 mg/dL), and a glucose concentration of 44.7 mg/dL (reference interval 52-105 mg/dL). There was marked atypia of the mononuclear cells, with abundant eosinophilic cytoplasm, marked anisocytosis and anisokaryosis, occasional binucleated cells, mitotic figures, and rare erythrophagia. The cytologic interpretation was marked, monocytoid-rich, mixed cell pleocytosis with cellular atypia worrisome for neoplasia. In addition to histiocytic neoplasia, differentials included granulomatous meningoencephalomyelitis, necrotizing meningoencephalitis, and granulomatous inflammation. The dog did not respond to anti-inflammatory and anticonvulsive therapy. At necropsy, a mass involving the meninges and subtending the neuropil of the right temporal lobe of the cerebrum was found. Histologically, the mass was composed of large, bizarre histiocytic cells with multinucleated forms and numerous mitotic figures. Using immunochemistry on cytologic and histologic samples, the pleomorphic histiocytic cells were positive for CD1c, CD11ad, CD45, lysozyme, and vimentin, and were negative for CD3, CD4, CD79a, CD90, and pancytokeratin. These findings supported a diagnosis of primary CNS malignant histiocytosis of dendritic antigen-presenting cell (CD1c+) origin. To our knowledge, this is only the third reported case of primary CNS histiocytic sarcoma in dogs, and the first to demonstrate strong immunochemical evidence for dendritic antigen-presenting cell origin.  相似文献   
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84.
Abstract: An adult castrated male Golden Retriever of unknown age was presented with a history of weight loss and progressive left thoracic limb lameness. On physical examination, a solid mass was palpated on the left scapula that had areas of lysis on radiographs and an area of cortical bone loss on ultrasound. Hepatomegaly, abdominal distension, and numerous intra‐abdominal soft tissue masses were also found. Fine‐needle aspirates of the scapula and several abdominal masses contained numerous free nuclei mixed with fewer individualized, intact cells that were round in shape and rarely formed small sheets. The cells had high nuclear to cytoplasmic ratios, central nuclei, coarsely stippled chromatin, 1–2 prominent nucleoli, and basophilic cytoplasm with indistinct cell borders. The cytopathologic interpretation was neuroendocrine neoplasia, either metastatic or multicentric. The dog was subsequently euthanized and based on gross and histologic findings at necropsy, a diagnosis of pheochromocytoma with multiple metastases was made. The neoplastic cells stained positive with Grimelius stain and were immunoreactive for synaptophysin and chromogranin A. Pheochromocytomas are rare tumors in dogs and uncommonly undergo distant metastasis, especially to bone.  相似文献   
85.
This paper describes a method to provide improved probability estimates that exposure to a specific dose of an airborne infectious pathogen will result in animal infection. Individual animals were exposed to a specific dose of airborne pathogen. Following exposure, animals were individually housed and monitored for evidence of infection. The detection of specific antibodies and/or the pathogen in diagnostic specimens was evidence that the exposure dose resulted in infection. If replicated over a range of doses, the results can be used to derive a dose-response curve for a variety of animal species and infectious pathogens. This information is useful in estimating the likelihood of infection associated with exposure to airborne infectious microorganisms. Applications include predicting the risk of transmission associated with exposure to airborne pathogens, modeling the transmission of airborne pathogens, and determining requirements for effective exposure doses for vaccines delivered in aerosols.  相似文献   
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87.
The μ-opioid receptor (MOR) is expressed in bovine, human, equine and canine oocytes, and in seasonal breeders, it is expressed with higher intensity during the anoestrous phase. Supplementation of in vitro maturation (IVM) medium with opioid agents, agonists or antagonists, was shown to affect oocyte maturation in several species such as rat, bovine and equine. This study reports the effects of supplementing IVM medium with naloxone (Nx), an opioid antagonist, on nuclear and cytoplasmic maturation rate of oocytes recovered from anoestrous bitches. Cytoplasmic maturation was examined in terms of mitochondrial (mt) distribution. In order to confirm the receptor-mediated action of Nx, in oocytes of anoestrous bitches, MOR expression was analyzed by Western blot. Cumulus–oocyte complexes, recovered from the ovaries of bitches in anoestrous, were cultured in vitro and Nx was added at the concentrations of 1 × 10−6, 1 × 10−8 and 1 × 10−10  m . The rate of oocytes resuming meiosis after culture in presence of 1 × 10−6  m Nx (29%) was significantly higher than that of oocytes of control group (12%; p < 0.05). However, treatment with Nx did not affect mt distribution pattern. In denuded oocytes and in corresponding cumulus cells, a doublet of 65 and 50 kDa was observed. We conclude that, in oocytes of anoestrous bitches, MOR is expressed and Nx significantly improves nuclear maturation rate. Further studies should be performed to elucidate the expression of other opioid receptors, such as δ and κ, and possible interactive effects of their antagonists on canine oocyte maturation.  相似文献   
88.
89.
Auto-anti-idiotypic antibodies (Aab-2s) were detected from pigs experimentally infected with porcine reproductive and respiratory syndrome virus (PRRSV). The Aab-2s were specific against the idiotypic antibodies (Ab-1s) to the envelope glycoprotein GP5 of PRRSV and were detected from serum samples collected between 21 and 98 days post-infection (DPI). Serological characterization indicated that the Aab-2s recognized the idiotype located within or near the antigen-combining sites of the anti-GP5 antibodies, which was shared by both mouse MAb anti-GP5 and swine polyclonal antibodies. The fact that the Aab-2 inhibited the anti-GP5 antibodies from binding to PRRSV and that they were detected at different time periods in pigs that cleared the infection prior to 98 DPI versus pigs in which virus was detected at 98 DPI suggests that Aab-2 antibodies may play a role in immunity to PRRSV infection.  相似文献   
90.
A 1-year-old spayed female Persian cat with alopecia and weight loss had numerous variably ulcerated dermal nodules. Cytologic examination of an aspirate of one of the nodules revealed pyogranulomatous inflammation along with septate hyphae and basophilic round bodies, 0.5–1.0 μm in diameter, surrounded by a thin clear halo (arthrospores). The cytologic diagnosis was dermatophytic pseudomycetoma. Histologically, there were dermal granulomas containing poorly staining, septate hyphae with bulbous spores embedded within abundant amorphous eosinophilic material (Splendore-Hoeppli reaction), and the histologic diagnosis was pseudomycetoma-associated chronic multifocal severe granulomatous dermatitis with lymphocytic perifolliculitis and furunculosis. Microsporum canis was cultured from the lesion. Pseudomycetomas are distinguished from fungal mycetomas, or eumycotic mycetomas, by the findings of multiple lesions, lack of a history of skin trauma, an association with dermatophytes, most commonly Microsporum canis , and, histologically, lack of true cement material and a more abundant Splendore-Hoeppli reaction in pseudomycetomas. Additionally, pseudomycetomas differ from dermatophytosis, in which lesions are restricted to epidermal structures. Persian cats have a high incidence of pseudomycetoma formation, suggesting a heritable predisposition. The prognosis is fair with systemic antifungal therapy. When examining cytologic specimens from Persian cats with single or multiple dermal nodules, especially if pyogranulomatous inflammation is present, a diagnosis of pseudomycetoma should be suspected and is warranted if arthrospores and refractile septate hyphae are present.  相似文献   
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