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The cognitive level of short essay questions taken from assessments of two veterinary courses at the Faculty of Veterinary Medicine of Utrecht University (FVMU) was evaluated using a simplified classification tool based on the taxonomy of Bloom. Classifications were made by teaching staff members (subject matter experts, or SME) and by faculty members not involved in teaching the course (non-subject matter experts, or NSME). To compare the cognitive level assigned by raters in the SME group to that assigned by the NSME group, each test item was assigned a modal taxonomic level. The results indicate that the agreement level between a pair of raters within a group (SME or NSME) differed (34% to 77% and linear weighted Cohen's kappa coefficient 0.12 to 0.60). The agreement level on the modal taxonomic level between the SME and NSME groups for the two courses was 65% and 73%, with a linear weighted Cohen's kappa coefficient of 0.43 and 0.63 respectively. The requirement of expertise of a subject for classification is discussed. The introduction of the classification tool had a positive effect on teaching staff members' awareness of the importance of the cognitive level of assessments. Improvements to the classification tool to obtain higher agreement levels are proposed.  相似文献   
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OBJECTIVE: To determine cyclooxygenase-2 (COX-2) selectivity, pharmacokinetic properties, and in vivo efficacy of ML-1,785,713 in dogs. ANIMALS: 21 healthy male and female mixed-breed dogs and 24 healthy male Beagles. PROCEDURE: Selectivity of ML-1,785,713 for inhibiting COX-2 was determined by comparing the potency for inhibiting cyclooxygenase-1 (COX-1) with that of COX-2 in canine blood. Pharmacokinetic properties were determined after i.v. (2 mg/kg) and oral (8 mg/kg) administration in female mixed-breed dogs. In vivo efficacy was evaluated in male mixed-breed dogs with urate crystal-induced synovitis. Prophylactic efficacy was evaluated by administering ML-1,785,713 two hours before induction of synovitis whereas therapeutic efficacy was determined by administering ML-1,785,713 one hour after induction of synovitis. RESULTS: Blood concentrations that resulted in 50% inhibition of COX-1 and COX-2 activity in vitro were 119.1 microM and 0.31 microM, respectively, and selectivity ratio for inhibiting COX-2 relative to COX-1 was 384. ML-1,785,713 had high oral bioavailability (101%), low systemic clearance (77 mL/min/kg), and an elimination half-life of 5.9 hours. ML-1,785,713 was efficacious when administered prophylactically and therapeutically to dogs with urate crystal-induced synovitis. CONCLUSIONS AND CLINICAL RELEVANCE: ML-1,785,713 is a novel, potent COX-2 inhibitor that is the most selective COX-2 inhibitor described for use in dogs to date. ML-1,785,713 has oral bioavailability and low systemic clearance that is comparable to other non-steroidal anti-inflammatory drugs. It is effective after prophylactic and therapeutic administration in attenuating lameness in dogs with urate crystal-induced synovitis. Drugs that specifically inhibit COX-2 and not COX-1 at therapeutic doses may have an improved tolerability profile, compared with nonselective non-steroidal anti-inflammatory drugs.  相似文献   
75.
OBJECTIVE: To determine if endoscopic-assisted foraminotomy significantly increased the area of the L7-S1 intervertebral foramen and if, over 12 weeks, stenosis would occur. STUDY DESIGN: Prospective, experimental study. ANIMAL POPULATION: Six clinically normal, 22-29 kg, adult dogs. METHODS: Using endoscopic assistance, unilateral L7-S1 foraminotomy was performed. Computed tomography of L7-S1 was performed preoperatively, immediately postoperatively, and at 12 weeks. Parasagittal foramen area (PFA) measurements were obtained at the entry, middle, and exit zones of the treated and control foramen for each period. Objective and subjective data were compared among dogs by time period and treatment status. RESULTS: Endoscopic-assisted foraminotomy resulted in a significant increase in the mean PFA of the entry and middle zones immediately postoperatively. The exit zone was not significantly larger at any time. The foramen remained significantly larger at 12 weeks only in the middle zone; however, some decrease in the surgically created foramen enlargement occurred at all 3 levels. The procedure was well tolerated but dogs did have transient, mild delay of functional return postoperatively. CONCLUSIONS: Endoscopic-assisted foraminotomy in dogs can be performed for certain foraminal regions, allowing enhanced visibility of the spinal canal. The foramen can be surgically enlarged at the entry and middle zones using this technique; however, some reduction of the foraminal enlargement occurs by 12 weeks. The clinical implications of this reduction cannot be determined from this study. CLINICAL RELEVANCE: Endoscopic-assisted foraminotomy could be used to improve intraoperative visualization in dogs with foraminal stenosis as a component of degenerative lumbosacral stenosis.  相似文献   
76.
A dog undergoing diagnostic myelography inadvertently received 0.5 ml diatrizoate meglumine (66%) and (10%) diatrizoate sodium via intrathecal injection. This resulted in post-operative seizures requiring extended sedation of the patient. The clinical course and management of this patient are presented. Complications associated with the inappropriate administration of a hyperosmolar contrast agent into the subarachnoid space and the results of similar accidents in humans are also discussed. The dog in the report recovered with no evidence of long trem neurological dam  相似文献   
77.
The catch per unit effort of Oreochromis mossambicus, Clarias gariepinus and Cyprinus carpio at different localities at Hartbeespoort Dam was investigated. Catches of the three species were between three and ten times higher on the southern shore of the lake than on the northern shore. The gradient of each locality was found to be the most important variable determining catch. Gill-net catches of O. mossambicus from littoral and limnetic stations indicated equal abundance of the species in these two habitats. The implications of the results for improved predictions of fish yield from lakes, and for management are discussed.  相似文献   
78.
For most of the year, Meyer’s parrots in the Okavango Delta do not form large feeding flocks, and groups larger than two or three are probably the result of opportunistic aggregation at favoured food items after dispersion from communal roosts. Communal roosting likely does not facilitate flocking unless the food resources are close to the roost site, but may function in anti-predator defence. Meyer’s parrots appear to be dependent on riverine forest, Acacia-Combretum marginal woodland and mopane woodland for roost sites in the Okavango Delta. They aggregated more during the breeding season due to their specialist nutritional requirements, and female dependence on food provisioning by the male parrots. Meyer’s parrots may be sedentary in the Okavango Delta, but the possibility of limited local movements in other areas (especially the Zimbabwean highlands) should be investigated.  相似文献   
79.
OBJECTIVE: To determine the effects of 2 doses of recombinant human bone morphogenetic protein-2 in an absorbable collagen sponge (rhBMP-2/ACS) on bone healing in dogs. ANIMALS: 27 adult dogs. PROCEDURES: Dogs underwent a mid-diaphyseal (1-mm) tibial osteotomy (stabilized with external skeletal fixation) and received an ACS containing 0.28 mg (0.2 mg/mL) or 0.56 mg (0.4 mg/mL) of rhBMP-2 or no treatment (control dogs). All dogs were examined daily; bone healing was assessed via radiography and subjective lameness evaluation every 2 weeks. After euthanasia at 8 weeks, tibiae were evaluated biomechanically and histologically. RESULTS: Control dogs required antimicrobial treatment for pin-site-related complications more frequently than did rhBMP-2/ACS-treated dogs. At 4 and 6 weeks, weight bearing was greater in dogs treated with rhBMP-2/ACS (0.2 mg/mL) than in control dogs, albeit not significantly. Compared with control treatment, both doses of rhBMP-2/ACS accelerated osteotomy healing at 4, 6, and 8 weeks, and the 0.2 mg/mL dose enhanced healing at 2 weeks; healing at 6 weeks was greater for the lower-dose treatment than for the higher-dose treatment. Histologically, healing at 8 weeks was significantly improved for both rhBMP-2/ACS treatments, compared with control treatment. Among groups, biomechanical variables did not differ, although less osteotomy-site failures occurred in rhBMP-2/ACS-treated groups. CONCLUSIONS AND CLINICAL RELEVANCE: In dogs that underwent tibial osteotomy, rhBMP-2/ACS (0.2 mg/mL) appeared to accelerate bone healing and reduce lameness (compared with control treatment) and apparently augmented bone healing more than rhBMP-2/ACS (0.4 mg/mL). Compared with control dogs, rhBMP-2/ACS-treated dogs required antimicrobial treatments less frequently.  相似文献   
80.
OBJECTIVES: To measure serum polymyxin B concentration after single and repeated IV infusions in horses. ANIMALS: 5 healthy horses. PROCEDURES: In study 1, 1 mg (6,000 U) of polymyxin B/kg was given IV and blood samples were collected for 24 hours. In study 2, 1 mg of polymyxin B/kg was given IV every 8 hours for 5 treatments and blood samples were collected until 24 hours after the last dose. Polymyxin B concentration was measured as the ability to suppress nitrite production by murine macrophages stimulated with lipopolysaccharide and interferon-alpha. Urine was collected prior to the first drug infusion and 24 hours after the fifth drug infusion for determination of urinary gamma-glutamyl transferase (GGT)-to-creatinine ratios. RESULTS: In study 1, mean +/- SEM maximal serum polymyxin B concentration was 2.93 +/- 0.38 microg/mL. Polymyxin B was undetectable 18 hours after infusion. In study 2, maximal polymyxin B concentrations after the first and fifth doses were 2.98 +/- 0.81 microg/mL and 1.91 +/- 0.50 microg/mL, respectively. Mean trough concentration for all doses was 0.22 +/- 0.01 microg/mL. A significant effect of repeated administration on peak and trough serum concentration was not detected. Urine GGT-to-creatinine ratios were not affected by polymyxin B administration. CONCLUSIONS AND CLINICAL RELEVANCE: Polymyxin B given as multiple infusions to healthy horses by use of this protocol did not accumulate in the vascular compartment and appeared safe. Results support repeated IV use of 1 mg of polymyxin B/kg at 8-hour intervals as treatment for endotoxemia.  相似文献   
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