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51.
A 9-year-old German Shepherd cross was presented with a history of dyspnoea, decreased activity, episodic collapse and abdominal distention. Cytological examination of thoracic and abdominal fluid demonstrated neoplastic cells, either round or mesenchymal in nature. The dog was found to have a mass in the heart-base region. Exploratory thoracotomy was performed to identify the exact nature of the mass histologically, and to determine if it was the source of neoplastic cells seen in the effusions. Histological diagnosis of the mass was mesothelioma. Postoperatively the dog developed thrombocytopenia, probably immune-mediated, which was treated with prednisone therapy. The dog developed signs of respiratory distress shortly before discharge and, due to its deteriorating condition, was euthanased. A necropsy was performed and tissues were collected for histological examination. The histological diagnosis was angiotropic intravascular lymphosarcoma. Diagnosis of mesothelioma was not confirmed. 相似文献
52.
Kraft A 《The Veterinary record》2004,155(20):620-624
In 1904, Liverpool veterinary school became the first UK veterinary school to be incorporated into a university. This weekend, it marks its centenary with a symposium celebrating veterinary science and its contribution to animal and human health and welfare. Here, Alison Kraft traces the history of the school and argues that its foundation was a turning point for veterinary education in the UK. 相似文献
53.
OBJECTIVE: To compare mechanical properties and failure characteristics of 2 methods of fixation for repair of a transverse, midbody fracture of the proximal sesamoid bone (PSB): 4.5-mm AO cortical bone screw (AO) placed in lag fashion and 4/5-mm Acutrak (AT) self-compressing screw. STUDY DESIGN: An in vitro biomechanical evaluation of intact forelimb preparations and forelimb preparations with a simulated midbody PSB fracture stabilized by a bone screw. SAMPLE POPULATION: Sixteen paired and 8 unilateral cadaveric equine forelimbs. METHODS: A midbody transverse osteotomy was created in the medial PSB of bilateral forelimbs of 8 equine cadavers. The osteotomized PSB in 1 forelimb from each cadaver was repaired with an AO screw. The osteotomized PSB in each contralateral limb was repaired with an AT screw. Eight unilateral intact control limbs were also studied. Mechanical properties were determined from axial compression, single cycle to failure, load-deformation curves. Failure characteristics were determined by evaluation of video images and radiographs. RESULTS: No statistically significant differences were found between repair groups. Both AO and AT groups had significantly lower mechanical properties than intact limbs except for stiffness. CONCLUSION: AO and AT constructs were mechanically comparable when used to stabilize a simulated midbody fracture of the medial PSB. Both constructs were mechanically inferior to intact limbs. Clinical Relevance- The AT screw should be considered for clinical use because of the potential for less soft tissue impingement and superior biocompatibility compared with the stainless-steel AO screw. However, postoperative external coaptation is necessary to augment initial fracture stability for either fixation method, and to maintain a standing metacarpophalangeal joint dorsiflexion angle between 150 degrees and 155 degrees. 相似文献
54.
Forster WA Zabkiewicz JA Riederer M 《Journal of agricultural and food chemistry》2006,54(8):3025-3032
The objective of this study was to determine whether a logistic-kinetic penetration model could be applied to whole plant uptake. Uptake over 24 h was determined for three model compounds, applied in the presence and absence of surfactants, into the leaves of two plant species. Data for two time intervals were used in the model to predict uptake at intermediate intervals and compared with experimental results. Overall, the model fit the whole plant uptake data well. The study confirmed that an increase (or decrease) in active ingredient (ai) concentration or an increase in contact area will have no effect on the penetration rate factor, q, within the normal working concentration range. This enabled uptake to be predicted at different times for concentrations of ai not already studied, having first derived q for one concentration of the formulation of interest and having 24 h (maximum) uptake results for all formulations and concentrations of interest. The advantages of the models and equations described are that few variables are required, and they are simple to measure. 相似文献
55.
Mehl ML Kyles AE Reimer SB Flynn AK Pollard RE Nyland T Kass PH Griffey SM Gregory CR 《Veterinary surgery : VS》2006,35(4):341-346
OBJECTIVE: To determine the relative importance of ischemic injury to delayed graft function (DGF) in cats. STUDY DESIGN: Experimental study. ANIMALS: Six intact female cats. METHODS: Cats had renal autograft transplantation without ureteral transection and reimplantation and a contralateral nephrectomy. Serum creatinine and blood urea nitrogen (BUN) concentrations were measured regularly and abdominal ultrasound was performed before surgery, the day after surgery and twice weekly thereafter. Ultrasound-guided renal biopsy was performed on day 7. Cats were euthanatized on day 21. Histology of the autograft, ureter, bladder, vascular anastomoses sites, and contralateral kidney were performed. Observations were compared with those from an historic group of research cats that had extravesicular ureteroneocystostomy and contralateral nephrectomy. RESULTS: Five cats completed the study. Serum creatinine and BUN concentrations increased after surgery, peaking at 3.2+/-0.8 and 77.6+/-15.9 mg/dL, respectively, 1-2 days after surgery. Serum creatinine concentration returned to the reference interval by 6 days after surgery. BUN gradually decreased in all cats but did not return to the reference interval by study end. Serum creatinine and BUN concentrations were consistently lower but not significantly so (P=.29 and .56, respectively) compared with the historic ureteroneocystostomy group. No ultrasonographic abnormalities or renal biopsy histologic abnormalities were observed. At necropsy, 1 autograft had generalized interstitial fibrosis. CONCLUSION: Harvesting the renal graft and the ischemia before revascularization causes impaired renal function after engraftment. CLINICAL RELEVANCE: The process of harvesting and reimplanting the renal graft can contribute to DGF in cats, independent of ureteral obstruction. 相似文献
56.
Oremus G Guerrero FD Alison MW Kimball MM Kim JH Foil LD 《Veterinary parasitology》2006,141(1-2):156-164
Between 1999 and 2002, the effect of mid-season doramectin treatments on the level of resistance in pyrethroid-resistant horn fly populations was examined at three separate Louisiana State University Agricultural Center research stations. The cattle were treated with pyrethroid ear tags in all years at all farms, and each farm received a mid-season doramectin treatment in 1 year. The number of weeks of control at Red River was 11 weeks higher in the year following the mid-season treatment of doramectin. At Macon Ridge, the number of weeks of control was 2 weeks higher in the year following the doramectin treatment. No change was observed at St. Joseph. The LC50s for fly populations tested at Macon Ridge and St. Joseph were found to increase for pyrethroids from the spring populations to the fall populations between 2000 and 2002. The LC50s for fly populations at Red River followed the same trends except in 2000, the year when the doramectin treatment was administered. Flies collected pre and post-treatment each year from St. Joseph and Red River were assayed for two alleles (kdr and skdr) associated with target site resistance to pyrethroids. Flies collected pretreatment at Macon Ridge in 1999 also were assayed for the kdr and skdr, and this population of flies had a frequency of 85.6% R-kdr alleles. At St. Joseph and Red River there was a general decline in the frequency of homozygous susceptible skdr (SS-skdr) and homozygous susceptible kdr (SS-kdr) individuals, as well as a general increase in homozygous resistant skdr (RR-skdr) and homozygous resistant kdr (RR-kdr) individuals, during the 4-year study. At both sites, the frequency of R-kdr alleles increased significantly in flies collected in the fall compared to flies collected in the spring with the exception of Red River in 2000, when dormacetin was applied. The frequency of the R-kdr alleles was significantly higher in flies collected in the fall compared to flies collected in the spring in the following year at both sites in two out of three comparisons. The frequency of R-skdr alleles was significantly lower in fly populations tested in the spring compared to fly populations tested in the fall at both farms in years when doramectin was not applied but there were no differences in the years when doramectin was applied. The frequency of R-skdr alleles was significantly higher in fly populations tested in the fall compared to in the spring the following year during all three comparisons at Red River and in one of three comparisons at St. Joseph. 相似文献
57.
Ko JC Payton ME White AG Galloway DS Inoue T 《Journal of the American Animal Hospital Association》2006,42(1):18-27
This crossover study tested the hypothesis that both diazepam and microdose medetomidine would comparably reduce the amount of propofol required to induce sedation. Four different medications, namely high-dose diazepam (0.4 mg/kg intravenously [IV]), low-dose diazepam (0.2 mg/kg IV), medetomidine (1 mug/kg IV), and placebo (0.5 mL physiological saline IV) were followed by propofol (8 mg/kg IV) titrated to a point where intubation could be performed. The effects of medetomidine were comparable to the effects of high-dose diazepam and significantly better than the effects of low-dose diazepam or placebo. Dogs in all treatment groups had transient hypoxemia, and induction and recovery qualities were similar. 相似文献
58.
The responses of 15 cats with histologically (n=14) or cytologically (n=1) confirmed nasal squamous cell carcinoma treated with (90)Strontium plesiotherapy were reviewed retrospectively. Cats were treated such that a total dose of 50Gy was delivered at a depth of 2mm, administered in five fractions over a 10-day period. Of the cats, 11 were stage T(2), three were T(is) and one had only a cytological diagnosis precluding staging. Eleven of the cats achieved complete response (no visible lesion after 6-8 weeks) following the first cycle of therapy, and two cats with partial response achieved complete response with a second cycle of therapy. The remaining two cats achieved partial response following therapy, but further intervention was declined. Euthanasia was performed in these two cats because of progressive disease after 81 and 142 days. Of the 85% of cats that achieved a complete response, there was no recurrence of disease during a follow-up period of 134-2,043 days (median 652 days). In addition to prolonged disease-free survivals, (90)Strontium therapy produced excellent cosmetic results from the owners' perspective. These results demonstrate that superficial squamous cell carcinoma of the feline nasal planum responds excellently to (90)Strontium plesiotherapy, and this form of therapy may offer advantages over other alternatives currently available. 相似文献
59.
Evaluation of concentration of voriconazole in aqueous humor after topical and oral administration in horses 总被引:2,自引:0,他引:2
Clode AB Davis JL Salmon J Michau TM Gilger BC 《American journal of veterinary research》2006,67(2):296-301
OBJECTIVE: To determine penetration of topically and orally administered voriconazole into ocular tissues and evaluate concentrations of the drug in blood and signs of toxicosis after topical application in horses. ANIMALS: 11 healthy adult horses. PROCEDURE: Each eye in 6 horses was treated with a single concentration (0.5%, 1.0%, or 3.0%) of a topically administered voriconazole solution every 4 hours for 7 doses. Anterior chamber paracentesis was performed and plasma samples were collected after application of the final dose. Voriconazole concentrations in aqueous humor (AH) and plasma were measured via high-performance liquid chromatography. Five horses received a single orally administered dose of voriconazole (4 mg/kg); anterior chamber paracentesis was performed, and voriconazole concentrations in AH were measured. RESULTS: Mean +/- SD voriconazole concentrations in AH after topical administration of 0.5%, 1.0%, and 3.0% solutions (n = 4 eyes for each concentration) were 1.43 +/- 0.37 microg/mL, 2.35 +/- 0.78 microg/mL, and 2.40 +/- 0.29 microg/mL, respectively. The 1.0% and 3.0% solutions resulted in significantly higher AH concentrations than the 0.5% solution, and only the 3.0% solution induced signs of ocular toxicosis. Voriconazole was detected in the plasma for 1 hour after the final topically administered dose of all solutions. Mean +/- SD voriconazole concentration in AH after a single orally administered dose was 0.86 +/- 0.22 microg/mL. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that voriconazole effectively penetrated the cornea in clinically normal eyes and reached detectable concentrations in the AH after topical administration. The drug also penetrated noninflamed equine eyes after oral administration. Low plasma concentrations of voriconazole were detected after topical administration. 相似文献
60.
Although the concept of food sovereignty is rooted in International Peasant Movements across the global south, activists have recently called for the adoption of this framework among low-income communities of color in the urban United States. This paper investigates on-the-ground processes through which food sovereignty articulates with the work of food justice and community food security activists in Oakland, California, and Seattle, Washington. In Oakland, we analyze a farmers market that seeks to connect black farmers to low-income consumers. In Seattle, we attend to the experiences of displaced immigrant farmers from Latin America and their efforts to address their food needs following migration. In both cases, we find that US based projects were constrained by broader forces of neoliberalism that remained unrecognized by local activists. In Oakland, despite a desire to create a local food system led by marginalized African Americans, emphasis on providing green jobs in agriculture led activists to take a market-based approach that kept local food out of the economic grasp of food-insecure neighborhood residents. In Seattle, the marginalization of the immense agroecological knowledge of Latino/an immigrant farmers rendered local food projects less inclusive and capable of transformative change. Taken together, these very different cases suggest that a shift towards food sovereignty necessitates a broad acknowledgement of and resistance to neoliberalism. 相似文献