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141.
Femoral head and neck excision was performed in 169 dogs over a 7 year period. A written questionnaire completed by 56 owners, evaluating a total of 72 joints, was the basis for retrospective evaluation of the efficacy of the procedures used. There were four surgical groups: femoral head and neck excision (FHNE) in dogs with body weights over 14 kg, the same procedure in dogs with body weights less than 14 kg (SMALL), femoral head and neck excision with muscle interposition (MI), and the wedge resection technique (WRT). Although differences in results were noted, there were no statistically significant differences between any of the groups for the percentage of leg use during normal activity (p greater than 0.05), mean postoperative time until leg use, use of the leg or hopping while running, or lameness with exercise (p greater than 0.10). The results of this study suggest that there is little advantage in performing the more time-consuming and traumatic muscle interposition and wedge resection procedures.  相似文献   
142.
Endothelial seeding of vascular grafts has been shown to decrease graft thrombogenicity and prolong longevity when implanted in vivo. Previous studies have utilized anatomic grafts to study endothelialization and healing. Anatomic thoracoabdominal grafts do not allow for sequential biopsy for evaluation of individual grafts nor do they approximate the environment for long bypass grafts used in limb salvage. This study evaluated the use of an extra-anatomic aortic bypass graft to assess the healing of endothelial cell seeded expanded polytetrafluoroethylene (ePTFE). Radionuclide angiography was used to evaluate graft patency and quantify blood flow through the graft. Dogs underwent placement of an extra-anatomic 60 cm long, 8 mm internal diameter, graft seeded with autologous endothelium. Grafts were biopsied from 2 weeks up to 1 year. Radionuclide studies were performed postimplantation and following each graft biopsy. Graft placement and biopsies were well tolerated in all dogs. Biopsied segments of graft allowed for sequential studies of the healing of implanted grafts by scanning electron and light microscopy. Flow through the implanted graft was close to 50% of the total caudal abdominal aortic flow. No significant difference in graft flow was noted either between animals or overtime.  相似文献   
143.
Résumé— Une dermite pyogranulomateuse provoquée par le protozoaire Neospora caninum a été diagnostiquée chez un Golden Retriever de 12 ans. Le nombreux nodules fistulisés étaient localisés au niveau de la tête et du thorax. De nombreux tachyzoites de N. caninum ont été retrouvés dans les biopsies des nodules et le diagnostic a été confirmé pas immunohistologie et examen en microscopie électronique. Le chien avait un titre de sérologie Neospora caninum de 3200 par immunofluorescence indirecte. Après un traitement à base de clindamycine pendant 45 jours, les lésions cutanées ont disparu. Le chien est probablement mort à cause d'un lymphosarcome. Il existait aussi une infection latente àToxoplasma gondii. les Neospora caninum n'ont pas pu être retrouvés par des techniques biologiques ni en culture ou par inoculation de souris à partir de prélèvements nécropsiques. Seuls des tachyzoites dégenérés ont pu être observés histologiquement. Ces observations montrent que la néosporose peut être envisagée dans le diagnostic différentiel des dermites pyogranulomateuses du chien et que la clindamycine est un médicament efficace pour traiter la néosporoe canine. [Dubey, J. P., Metzger, F. L., Hattel, A. L., Lindsay, D. S., Fritz, D. L. Canine cutaneous neosporosis: clinical improvement with clindamycin (Néosporose cutanée canine: amélioration clinique par la clindamycine). Resumen— Se diagnosticó una dermatitis piogranulomatosa causada por el protozoo parásito Neospora caninum en un perro de raza Golden Retriever de 12 años. El animal presentaba varios nódulos en la piel de la cabeza y tórax. Se observaron numerosos taquizoitos de N. caninum en los cortes histológicos de tejido obtenido mediante biopsia de dichos nódulos y el diagnóstico fue confirmado por tinción inmunohistológica y por microscopia electrónica. El perro mostró un titulo de anticuerpos contra N. caninum de 1:3,200 en la prueba de fluorescencia indirecta. Las lesiones cutáneas se resolvieron tras un tratamiento con hidroclorido de clindamicina durante 45 dias. El perro murió posteriormente a causa de un linfoma y presentaba también una infestación latente por Toxoplasma gondii. No se pudo demostrar la presencia de Neospora caninum mediante bioensayos en cultivos celulares ni en ratones inoculados con tejido canino obtenido en la necrospia. Tan solo se pudieron observar taquizoitos degenerados de N. caninum en tejido cutáneo obtenido en la necrospia. Estos hallazgos indican que se debe incluir neosporosis en el diagnóstico diferencial de dermatitis piogranulomatosas en el perro y que la clindamicina puede ser un fármaco eficaz para el tratamiento de la neosporosis cutánea. [Canine cutaneous neosporosis: clinical improvement with clindamycin (Neosporosis cutánea canina: mejora clinica con clindamicina). Abstract— Pyogranulomatous dermatitis caused by the protozoan parasite Neospora caninum was diagnosed in a 12-year-old Golden Retriever dog. Multiple draining nodules were located in the skin of the head and thorax. Numerous tachyzoites of N. caninum were found in histologic sections of the biopsy tissue from the cutaneous nodules and the diagnosis was confirmed by immunohistochemieal staining and by electron microscopic examination. The dog had a 1:3200 serum antibody titer to N. caninum in the indirect fluorescent antibody test. The cutaneous lesions resolved after a 45-day treatment with clindamycin hydrochloride. The dog eventually died because of lymphosarcoma and also had a latent infection with Toxoplasma gondii. Neospora caninum could not be demonstrated by bioassays in cell culture or mice inoculated with canine tissue obtained at necropsy. Only degenerating N. caninum tachyzoites were seen in skin tissue taken at necropsy. These observations indicate that neosporosis should be considered in the differential diagnosis of pyogranulomatous dermatitis in dogs and that clindamycin may be an effective drug for treating cutaneous neosporosis.  相似文献   
144.
Inherited progressive spinal myelinopathy in Murray Grey cattle   总被引:1,自引:0,他引:1  
In a breeding experiment conducted to determine the mode of inheritance of progressive spinal myelinopathy, semen from a Murray Grey bull which had previously sired affected calves was used to inseminate 120 cows. Female progeny were then inseminated with semen from the same bull. Of the 51 calves born, six (11.8%) had spinal cord lesions consistent with progressive spinal myelinopathy. From analysis of pedigrees and the results of the breeding experiment it was concluded that the condition was inherited as an autosomal recessive condition in Murray Grey cattle.  相似文献   
145.
146.
A continuous, underway fish egg sampler   总被引:2,自引:0,他引:2  
We describe a method to sample the highly contagious distribution of pelagic fish eggs. CUFES, the continuous, underway fish egg sampler, consists of a submersible pump, concentrator, electronics and sample collector. This system operates continuously and under nearly all sea conditions, providing a real-time estimate of the volumetric abundance of pelagic fish eggs at pump depth, usually 3 m. CUFES-derived estimates of volumetric abundance agree well with those from nets towed at pump depth and with areal abundance estimated from vertically integrated plankton tows. CUFES has been used successfully to sample the eggs of menhaden, pinfish, sardine, and anchovy off the coasts of the eastern and western United States and South Africa. Two large patches of eggs of the Atlantic menhaden were sampled off North Carolina in winter 1993–94, had a linear scale of 5–10 km, and were found in waters between the Gulf Stream and mid-shelf front. Spawning location may be related to bathymetry. CUFES is now being used to estimate spawner biomass by the daily egg production method. An optical plankton counter provided accurate estimates of the number of Atlantic menhaden eggs sample by CUFES.  相似文献   
147.
148.
Several published models exist for simulating vertical profiles of pelagic fish eggs, but no one has rigorously assessed their capacity to explain observed variability. In this study, we applied a steady‐state model, with four different formulations for vertical diffusivity, to northern anchovy (Engraulis mordax) and Pacific sardine (Sardinops sagax) eggs in the California Current region. Vertical mixing profiles, based on wind speed and hydrography, were combined with estimated terminal ascent velocities of the eggs based on measurements of egg buoyancy and size, to simulate the vertical profiles of the eggs. We evaluated model performance with two data sets: (1) vertically stratified tows for both species and (2) paired samples for sardine eggs from 3‐m depth and in vertically integrated tows. We used two criteria: whether the model predicted individual observed vertical profiles (1) as well as the observed mean and (2) better than the observed mean. Model predictions made with the formulation producing the most gradual profile of vertical diffusivity provided the best match to observations from both data sets and for both species. Addition of a random error term to the terminal ascent velocity further improved prediction for anchovy eggs, but not sardine. For the paired data, model prediction of integrated abundance from abundance at 3‐m depth had significantly lower mean square error than prediction based on a linear regression of 3 m on integrated abundance. Our results support the feasibility of using data from the Continuous Underway Fish Egg Sampler quantitatively as well as qualitatively in stock assessments.  相似文献   
149.
Abstract  The ability of a commercial fisher to limit red drum, Sciaenops ocellatus (Linnaeus), bycatch was evaluated by comparing the catch of directed sets (net site chosen by the commercial fisher) vs randomly placed gillnets during 70 days of gillnetting ( n  = 691 sets). Catch rate did not differ between directed sets and nets set randomly. Thus, fisher experience did not lead to reduced bycatch; however, this may have been influenced by overall low red drum bycatch (0.41 fish net−1 for 12 h sets and 0.59 fish net−1 for 24 h sets). Catch rates of southern flounder were much higher at 3.97 and 3.37 fish net−1 for 12 h and 24 h sets, respectively. Fishing 10 nets per day, the catch of red drum exceeded the daily bag limit of seven red drum on 23% of the days. Of the 326 red drum retrieved from gillnets, 32.5% were dead at the time of retrieval; but only 15 of the 106 dead red drum had to be discarded due to size limits, and six were discarded dead based on bag limits. Current fisheries management regulations (bag limit and window limit of 457–686 mm) are supported by these findings given the conditions (e.g. red drum densities) at which the study was performed.  相似文献   
150.
Abstract. A bacterium resembling Aeromonas salmonicida and determined to be the aetiologic agent of a cutaneous ulcerative disease in goldfish Carassius auratus (L.) was further characterized in this study.
Forty-five isolates of the bacterium (43 from the United States and one each position (moles % guanine plus cytosine) and DNA homology. The bacteriological atypical A. salmonicida previously described. Several important biochemical characteristics distinguished the goldfish isolates from typical A. salmanicida , but the DNA binding experiments indicated a high degree of relatedness between the goldfish isolates and typical A. salmonicida strains.  相似文献   
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