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21.
Objective —To describe function and identify factors that affect outcome in dogs undergoing limb salvage surgery for osteosarcoma (OS) of the proximal humerus.
Study Design —A retrospective study of dogs in which OS of the proximal humerus was treated with limb salvage surgery.
Animals —17 client-owned dogs.
Methods: Records were analyzed for functional outcome, recurrence, metastasis, and survival.
Results —Outcome was good to excellent in 12% of dogs. Recurrence, metastasis, and survival were significantly affected by completeness of surgical margins. Double plating of the distal allograft-host junction significantly reduced frequency of biomechanical failure.
Conclusions —Limb salvage surgery for OS of the proximal humerus did not result in acceptable function and was fraught with postoperative complications. Outcome was significantly affected by completeness of surgical margins.
Clinical Relevance —Limb salvage surgery for OS of the proximal humerus in dogs cannot be recommended until improvement in functional outcome and reduction in postoperative complications can be achieved. The dependence of outcome on completeness of surgical margins supports aggressive en bloc resection and marking and evaluating surgical margins.  相似文献   
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Radionuclide ventriculography has been used in humans to evaluate valvular incompetency. The stroke volume ratio, derived from the radionuclide ventriculogram, is used to quantify the severity of mitral regurgitation (MR). Previous studies conducted in humans have shown that left to right stroke volume ratio increases as the severity of MR increases. In this study, we evaluated radionuclide ventriculography as a noninvasive method to detect MR in dogs with surgically created mitral insufficiency. Six male and three female adult, conditioned mongrel dogs were used. Scintigraphic studies were performed prior to and 4 weeks after surgically created MR. Because of the overlap of the left and right ventricles when viewed from a left lateral position, we combined data from a first-pass radionuclide angiocardiogram with the radionuclide ventriculogram to obtain a corrected stroke volume ratio. Blood flow transit parameters were also derived from the first-pass radionuclide angiocardiogram. Standard left ventricular functional indices were also measured from the radionuclide ventriculogram. On the left lateral view of the heart, 25 to 30% of the right ventricular volume overlaps the left ventricle. After correcting for the overlap, the stroke volume ratio of normal dogs was 1.17±0.178 (mean±SD), which increased to 2.06±0.41 (mean±SD) (p<.001) 4 weeks after creation of MR. The was no significant change in left ventricular ejection fraction or peak rate of ejection following MR. The transit times of blood through the left ventricle were measured from the first-pass radionuclide angiocardiogram and were expressed as half-time clearance, peak clearance rate, and time to peak clearance rate. The baseline half-time clearance was 2.07±0.71 s (mean±SD), which increased to 6.70±4.89 s (mean±SD) (p=.02) after creation of MR. The baseline peak clearance rate was 49.75±8.96 cts/s (mean±SD), which decreased to 23.12±6.84 cts/s (mean±SD) (p<.001) after creation of MR. Stroke volume ratios significantly increased following creation of MR. Blood flow transit through the left ventricle slowed following creation of MR. The variability of these parameters were small in the baseline studies, suggesting these techniques may be clinically useful to gauge the severity of MR in dogs.  相似文献   
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The scintigraphically measured percentage dose uptake of 99mTc-DTPA by the kidneys and the plasma clearance of 99mTc-DTPA have been reported to correlate well with inulin clearance. These two parameters were evaluated in seven dogs with known or suspected naturally occurring renal disease and compared to simultaneously measured renal inulin clearance. Correlation between inulin clearance and the 99mTc-DTPA plasma clearance was better ( p =.0016) than the correlation between the percentage DTPA uptake by the kidney. It was concluded that measurement of 99mTc-DTPA plasma clearance is a more accurate method to estimate global glomerular filtration rate (GFR) than the percentage kidney uptake.  相似文献   
24.
Eight synthetic casting materials were evaluated with respect to tensile and fatigue strengths, exothermicity (evolution of heat during polymerization), permeability (porosity), radiolucency, and cost. Strength determination for a five-layer sample included measurement of the ultimate load at which a material failed, the ability to absorb energy, and the stiffness a material possessed after application of a cyclic stress. Results indicated that Vet Cast was superior with respect to tensile and fatigue strengths. The exothermic reaction associated with the "curing" or polymerization process was evaluated and not considered excessive although Ultra Cast attained a temperature of 48.0°C and was uncomfortable to handle during application. Permeability was determined. Delta Lite and Hexcelite NS were the most permeable materials and dried more rapidly and thoroughly after immersion than the other casting materials. Hexcelite NS was considered the least radiolucent material and was the most expensive material studied. Each of the synthetic casting materials demonstrated superiority in one or more of the categories tested. No one product demonstrated consistent superiority in criteria appropriate for clinical application.  相似文献   
25.
Objective — This study evaluates the association between dental procedures and bacteremia in dogs, including a comparison of bacteria isolated from plaque and blood, severity of the bacteremia versus the severity of dental disease, and the longevity of bacteremia.
Study Design — Bacteria cultured from the blood over time were compared with those isolated from the plaque and crevicular fluid and in relation to severity of dental disease.
Animals or Sample Population — Twenty adult greyhounds.
Methods — Blood samples were collected for culture before induction of general anesthesia, immediately after intubation, 20 minutes after initiation of the dental procedure, and at 10-minute intervals until 10 minutes after the dental procedure was completed. Samples of plaque were taken for microbiological culture.
Results — Sixty to ninety percent of the bacterial genera isolated from the plaque were present in the blood. Dogs classified according to severity of dental disease showed no difference in the total number of different species or number of different Gram-negative, Gram-positive, or anaerobic bacteria isolated from plaque or blood (P <.05). Bacteremia was present in all of the dogs studied, within 40 minutes from the initiation of the dental procedure, regardless of the severity of oral disease.
Conclusions — Gram-negative, Gram-positive, and anaerobic bacteria are present in blood during dental procedures; the bacteremia can persist beyond the dental procedure, and is not associated with the severity of dental disease.
Clinical Relevance — The nature and extent of bacteremia occuring during routine dental procedures is important in understanding a potential risk to dogs.  相似文献   
26.
A retrospective survey was carried out at a Florida racetrack in 1984, to determine the prevalence of exercise-induced pulmonary hemorrhage (EIPH) in Appaloosa horses. Of 94 horses examined endoscopically between 30 and 90 minutes after racing, forty-nine (52%) were found to exhibit some degree of EIPH. There was a significantly increased prevalence of EIPH with increasing age in this population. An increased prevalence of EIPH was noted with mares and geldings as compared with stallions, but this was not statistically significant. More horses bled from the right lung than from the left, but the difference was statistically insignificant. An increased prevalence of EIPH with distance run was evident, but this was not significant when animals of the same age were examined.  相似文献   
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