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排序方式: 共有3984条查询结果,搜索用时 140 毫秒
1.
Hege Kippenes DVM Patrick R. Gavin DVM PhD Susan L. Kraft DVM PhD Ronald D. Sande DVM MS PhD Russell L. Tucker DVM 《Veterinary radiology & ultrasound》2001,42(2):130-133
The pituitary gland was measured from transverse magnetic resonance T1-weighted images after Gadolinium administration in 96 dogs weighing from 13 to 45 kg. The measurements were done by hand with calipers. The mean (+/- standard deviation) pituitary gland height was 5.1 mm (+/-0.9 mm). The mean width was 6.4 mm (+/- 1.1 mm). The correlation coefficient between pituitary and brain measurements, between pituitary measurement and body weight, and brain measurements and body weight was 0.0 to 0.3. A hyperintense region was present on T1-weighted images in the center of the pituitary gland in 64% of the dogs. At necropsy the pituitary glands were grossly and histologically normal. No pituitary gland measurements were performed at necropsy. 相似文献
2.
Jeffrey R. Crass MD Ronald L. Genovese VMD James A. Render DVM Errol M. Bellon MD 《Veterinary radiology & ultrasound》1992,33(4):206-216
Ultrasonography and MRI have become valuable tools for imaging of tendon injuries. The current study examines the histopathologic basis for the imaging abnormalities. Five injured equine forelimbs and two normal contralateral limbs were studied with high resolution real time ultrasound and MRI. Histologic sections were made and correlated with the diagnostic images. All lesions were readily seen by both modalities. Lesions characterized by hemorrhage, edma, and cellular infiltration were sonolucent on ultrasound and bright on MRI images. MRI returned to normal as fibrogenesis ensued. Ultrasound images remained abnormal until fibrillar reallgnment occured with completion of the healing process. High resolution real time ultrasound and MRI both accurately reflect the tissue abnormalities in acute tendon injuries. The injured horse does appear to be an effective model for correlative imaging studies of tendon injuries. 相似文献
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Jørgen Lauritzen Jensen 《Journal of Wood Science》2005,51(6):577-582
A quasi-non-linear fracture mechanics model based on beam on elastic foundation theory is applied for analysis of the splitting
failure of dowel joints loaded perpendicular to grain. Simply supported beams symmetrically loaded by two dowels are considered,
and the effects of edge distance, dowel spacing, and distance between dowels and supports are accounted for. The foundation
modulus used in the beam on elastic foundation model is chosen so that the perpendicular-to-grain tensile strength and fracture
energy properties of the wood are correctly represented. This ensures that a conventional stress analysis and failure criterion
lead to the same solution as the compliance method of fracture mechanics. A semiempirical efficiency factor is proposed to
account for the influence of the total beam depth, which does not enter the beam on elastic foundation model, but the effect
of which is evident from tests. It is shown that the so-called Van der Put/Leijten model, which recently has been adopted
in Eurocode 5, appears as a special case of the model presented. Tests on simply supported beams with a single dowel joint
at midspan are compared with the theoretical predictions. Various edge distances, beam depths, and spans were tested. 相似文献
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Ronald D. Hodges DVM Russell L. Tucker DVM James J. Brace DVM 《Veterinary radiology & ultrasound》1993,34(4):249-252
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Biofilm bacteria: formation and comparative susceptibility to antibiotics 总被引:17,自引:0,他引:17
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Merle E. Olson Howard Ceri Douglas W. Morck Andre G. Buret Ronald R. Read 《Canadian journal of veterinary research》2002,66(2):86-92
The Calgary Biofilm Device (CBD) was used to form bacterial biofilms of selected veterinary gram-negative and gram-positive pathogenic bacteria from cattle, sheep, pigs, chicken, and turkeys. The minimum inhibitory concentration (MIC) and minimum biofilm eradication concentration (MBEC) of ampicillin, ceftiofur, cloxacillin, oxytetracycline, penicillin G, streptomycin, tetracycline, enrofloxacin, erythromycin, gentamicin, tilmicosin, and trimethoprim-sulfadoxine for gram-positive and -negative bacteria were determined. Bacterial biofilms were readily formed on the CBD under selected conditions. The biofilms consisted of microcolonies encased in extracellular polysaccharide material. Biofilms composed of Arcanobacterium (Actinomyces) pyogenes, Staphylococcus aureus, Staphylococcus hyicus, Streptococcus agalactiae, Corynebacterium renale, or Corynebacterium pseudotuberculosis were not killed by the antibiotics tested but as planktonic bacteria they were sensitive at low concentrations. Biofilm and planktonic Streptococcus dysgalactiae and Streptococcus suis were sensitive to penicillin, ceftiofur, cloxacillin, ampicillin, and oxytetracycline. Planktonic Escherichia coli were sensitive to enrofloxacin, gentamicin, oxytetracycline and trimethoprim/ sulfadoxine. Enrofloxacin and gentamicin were the most effective antibiotics against E. coli growing as a biofilm. Salmonella spp. and Pseudomonas aeruginosa isolates growing as planktonic populations were sensitive to enrofloxacin, gentamicin, ampicillin, oxytetracycline, and trimethoprim/sulfadoxine, but as a biofilm, these bacteria were only sensitive to enrofloxacin. Planktonic and biofilm Pasteurella multocida and Mannheimia haemolytica had similar antibiotic sensitivity profiles and were sensitive to most of the antibiotics tested. The CBD provides a valuable new technology that can be used to select antibiotics that are able to kill bacteria growing as biofilms. 相似文献
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H. Kruse M. Hofshagen S. I. Thoresen W. P. Bredal I. Vollset N. E. Søli 《Veterinary research communications》1996,20(3):205-214
In a retrospective study, 1538 strains of -haemolysin-producing Staphylococcus species isolated from dermatitis in dogs at three veterinary clinical microbiology laboratories in Norway during 1986–87 and 1993–94 were investigated for their antimicrobial susceptibility. None of the strains was resistant to cloxacillin, cephalexin or the quinolones enrofloxacin and ciprofloxacin. More than 96% of the strains were susceptible to trimethoprim-sulphonamide, bacitracin and fucidic acid. Between 67% and 89% of the strains were susceptible to erythromycin, lincosamides, tetracycline, neomycin and chloramphenicol. Only 37.9% of the strains were susceptible to penicillin. The frequency of penicillin resistance increased significantly between the first and second periods, from 46.0% to 58.6%. The frequency of resistance to lincomycin, clindamycin and erythromycin also increased significantly between the first and second periods, from 3.0%, 2.1% and 3.3% to 25.5%, 19.5% and 24.8%, respectively. A moderate increase in resistance to tetracycline was also noted, from 20.4% in the first to 27.6% in the second period. On the other hand, the frequency of resistance to trimethoprim-sulphonamide decreased significantly from 4.1% in the first to 0.9% in the second period. Many different resistance patterns were observed in each period. However, the proportion of multiresistant strains increased from 2.1% in the first to 10.2% in the second period. There was a decrease in resistance to the combination of trimethoprim-sulphonamide and penicillin from the first to the second period. Resistance to the combination of lincosamides and pencillin increased. For the combinations penicillin-tetracycline-lincosamides, pencillin-lincosamides-erythromycin, and pencillin-tetracycline-lincosamides-erythromycin, there was a striking increase in resistance between the first and the second periods.Abbreviations CVL
Central Veterinary Laboratory
- NCVM
Norwegian College of Veterinary Medicine
- NVL
Norwegian Veterinary Laboratory 相似文献