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881.
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883.
Ramos JR Howard RD Pleasant RS Moll HD Blodgett DJ Magnin G Inzana TJ 《Veterinary surgery : VS》2003,32(3):251-261
OBJECTIVE: To characterize the elution and bioactivity of metronidazole and gentamicin sulfate polymerized, individually and in combination, with polymethylmethacrylate (PMMA). STUDY DESIGN: In vitro experimental study. METHODS: PMMA beads containing metronidazole (3 concentrations), gentamicin sulfate, or metronidazole and gentamicin sulfate were immersed in 5 mL of phosphate-buffered saline in triplicate. Eluent was replaced at specified time intervals for 1 or 21 days, and antibiotic concentrations were measured by high-performance liquid chromatography. Changes in antibiotic bioactivity attributable to polymerization or copolymerization of the antibiotics with PMMA, ethylene oxide sterilization, and storage of AIPMMA beads containing metronidazole were evaluated. RESULTS: Antibiotic elution patterns were similar for all groups. Day 1 elution for groups containing metronidazole or gentamicin individually represented a mean 63%-66% and 79%, respectively, of the 21-day total. Approximately 50% of the day 1 elution occurred during the first hour. The elution of metronidazole was dose dependent. The elution of metronidazole (day 3-21) and gentamicin (all days) was significantly greater when metronidazole and gentamicin were combined (P <.05). The addition of metronidazole delayed polymerization of PMMA. Neither polymerization nor copolymerization of metronidazole and gentamicin with PMMA, gas sterilization, or 2-month storage of beads containing metronidazole significantly affected antimicrobial bioactivity. CONCLUSIONS: Metronidazole elution from PMMA was dose dependent. Copolymerization of metronidazole and gentamicin sulfate in PMMA resulted in increased rates of elution. Intraoperative preparation of metronidazole-impregnated PMMA beads is not practical, but sterilization and storage for 2 months should not affect efficacy. CLINICAL RELEVANCE: The local delivery of biologically active metronidazole and gentamicin by elution from PMMA is feasible. 相似文献
884.
Intermittent bolus injection versus continuous infusion of furosemide in normal adult greyhound dogs 总被引:5,自引:0,他引:5
Adin DB Taylor AW Hill RC Scott KC Martin FG 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(5):632-636
Several studies in human subjects have demonstrated greater diuresis with constant rate infusion (CRI) furosemide than intermittent bolus (IB) furosemide. This study was conducted to compare the diuretic efficacy of the same total dose of IB furosemide and CRI furosemide in 6 healthy, adult Greyhound dogs in a randomized crossover design with a 2-week washout period between treatments. For IB administration, dogs received 3 mg/kg at 0 and 4 hours. For CRI administration, dogs received a 0.66 mg/kg loading dose followed by 0.66 mg/kg/h over 8 hours. The same volume of fluid was administered for both methods. Urine output was quantified hourly. Urine electrolyte concentrations, urine specific gravity (USG), packed cell volume (PCV), total protein (TP), serum electrolyte concentrations, total carbon dioxide (TCO2), serum creatinine (sCr), and blood urea nitrogen (BUN) were determined every 2 hours. Urine production and water intake were greater (P < or = 0.05) for CRI than IB. Urine sodium and calcium losses were greater (P < 0.05) and urine potassium loss was less (P = 0.03) for CRI than IB, but there was no evidence of a difference between methods for urine magnesium and chloride losses. Serum chloride concentration was less (P < 0.001), sCr concentration greater (P = 0.04). TP greater (P = 0.01), and PCV greater (P = 0.003) for CRI than IB. No differences in USG, TCO2, BUN, or serum potassium, sodium, and magnesium concentrations were detected between methods. The same total dose of CRI furosemide resulted in more diuresis, natriuresis, and calciuresis and less kaliuresis than IB furosemide in these normal Greyhound dogs over 8 hours, suggesting that furosemide is a more effective diuretic when administered by CRI than by IB. 相似文献
885.
Evans J Levesque D Knowles K Longshore R Plummer S 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(3):304-310
The currently recommended treatment for metronidazole toxicosis is drug discontinuation and supportive therapy. Reported recovery times are 1-2 weeks. The records of 21 dogs with metronidazole toxicosis were retrospectively analyzed to determine whether diazepam improved recovery. The dosage and duration of metronidazole therapy and the response and recovery times of 13 dogs treated with diazepam were compared to those of 8 dogs receiving only supportive care. Response time was defined as the time to resolution of the debilitating clinical signs. Recovery time was the time to resolution of all residual clinical signs. The average dosage and duration of metronidazole administration for the diazepam-treated and untreated groups were 60.3 mg/kg/d for 44.9 days and 65.1 mg/kg/d for 37.25 days. The protocol for diazepam administration consisted of an initial i.v. bolus and then diazepam PO q8h for 3 days. The average dosage of both the i.v. and PO diazepam was 0.43 mg/kg. The average response time for the diazepam-treated dogs was 13.4 hours compared to 4.25 days for the untreated group. Recovery time also was markedly shorter for the diazepam-treated dogs (38.8 hours) compared to the untreated group (11 days). Results of this study showed that dogs with metronidazole toxicosis recover faster when treated with diazepam. Although the mechanism of metronidazole toxicosis or how diazepam exerts its favorable effect is not known, it is likely related to modulation of the gamma-aminobutyric acid (GABA) receptor within the cerebellar and vestibular systems. 相似文献
886.
Scott HM Soskolne CL Wayne Martin S Ellehoj EA Coppock RW Guidotti TL Lissemore KD 《Preventive veterinary medicine》2003,57(1-2):15-34
We describe two approaches for exposure assessment that we used in a large-scale retrospective cattle study conducted in Alberta, Canada. Sulfur dioxide (SO(2)) was the surrogate measure of exposure to a complex mixture of combusted sour-gas emissions. Monthly air pollution dispersion modeling (1985-1994) (based on individual industrial source processing-plant engineering specifications, emission volumes, and meteorologic information) provided exposure isopleths of sulfur dioxide concentration from each of 231 sour-gas processing-plants across the province. In contrast, a simpler measure of proximity to source(s) of varying emission rates was applied in a geographical information system based on simplified pollution decay at increasing distances from each point source. Province-wide (663,000 km(2)) surface analysis (by exposure-level classification) produced a contingency coefficient of 0.68 between the two exposure estimates. Annual exposure estimates at the 1382 dairy and 5726 beef cow-calf farms studied were highly correlated over the 10-years period (r(spearman)=0.82 and 0.83, respectively), while monthly exposure estimates were somewhat less correlated (r(spearman)=0.80 and 0.82, respectively) for the two exposure assessment methods. Crude exposure estimates from each method were similar in both direction and magnitude. 相似文献
887.
Stear MJ Bishop SC Henderson NG Scott I 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2003,4(1):45-52
Infection of sheep with the abomasal nematode Teladorsagia circumcincta can cause a relative protein deficiency and reduce growth rate in growing lambs. A key event appears to be the destruction of junctions between epithelial cells. If the infection is heavy or prolonged, this leads to increased mucus production, hyperplasia, decreased acid production, gastrinemia, inappetance and pepsinogenemia. The severity of the infection depends upon the extent of concurrent infection, the nutritional status of the host and genetically controlled variation in the ability to mount protective immune responses. 相似文献
888.
Downy mildew, caused by Peronospora arborescens, has become the major disease affecting oilseed poppy (Papaver somniferum) since its first record in Tasmania in 1996. Two field trials conducted in 2000 and 2001 studied the progression and spatial distribution of downy mildew epiphytotics. The logistic and exponential models best described the progression of disease incidence and severity, respectively. Incidence and severity increased rapidly following canopy closure. In 2001, incidence increased from 0.16%, prior to canopy closure, to 100% at late flowering (40 days). Spatial analyses of epiphytotics were conducted by fitting the beta-binomial and binomial distributions, median runs analysis, and the spatial analysis by distance indices. All analyses demonstrated that the distribution of incidence and severity was strongly spatially aggregated from canopy closure until at least late flowering. These results suggest that secondary spread from a few primary infections is the major factor in epiphytotics. 相似文献
889.
890.
Antimicrobial susceptibility of hazard analysis critical control point Escherichia coli isolates from federally inspected beef processing plants in Alberta, Saskatchewan, and Ontario
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Van Donkersgoed J Manninen K Potter A McEwen S Bohaychuk V Klashinsky S Deckert A Irwin R 《The Canadian veterinary journal. La revue veterinaire canadienne》2003,44(9):723-728
A survey to estimate the prevalence of antimicrobial resistance in Escherichia coli was conducted in 7 Canadian federally inspected processing plants during 2001. Escherichia coli isolates were recovered during routine hazard analysis critical control point sampling from beef carcasses and trim and subsequently tested for their antimicrobial susceptibility by using susceptibility panels. Of the 2653 isolates analyzed, 68% were sensitive to all 18 antimicrobials tested. For 14 of the 18 antimicrobials evaluated, the percentage of resistant isolates was < or = 1. Twenty-five percent of the isolates were resistant to tetracycline, 9% to sulfamethoxazole, 7% to streptomycin, and 3% to ampicillin. Multiple resistance was found in 12% of the isolates, with 7% showing resistance to 2 antimicrobials, 2% to 3 antimicrobials, 2% to 4 antimicrobials, and 1% to 5 or more antimicrobials. Forty-five different antimicrobial resistance patterns were observed. The reasons for the development of the antimicrobial resistance were not investigated in this study. This study was useful as a pilot to help to develop a national antimicrobial resistance surveillance program in Canada. This study indicates that laboratory standardization is possible for consistent results across the country and that the indicator organism, E. coli, is fairly easy to obtain for surveillance but Salmonella are not, due to their low prevalence in beef. 相似文献