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611.
David A Fagan James E Oosterhuis Kurt Benirschke 《Journal of zoo and wildlife medicine》2005,36(1):36-43
"Lumpy jaw" of artiodactyls and macropods, although often considered a manifestation of actinomycosis, is actually an osteomyelitis, perhaps commencing with a dental root abscess or trauma to the jaw. Anaerobes may be cultured from the lesions, and vegetable matter may be impacted in them. It is a chronic disease and difficult to treat. Successful treatment may include draining the abscess, cleaning the cavity with saline and antibiotics, flushing with a combination of hydrogen peroxide-sodium hypochlorite and Betadine, and apicoectomy and endodontic filling when active inflammation has subsided. 相似文献
612.
James?D.?WickhamEmail author Kurt?H.?Riitters Timothy?G.?Wade K.?Bruce?Jones 《Landscape Ecology》2005,20(7):791-798
The continuing degradation of United States surface waters by excessive nutrient loads has motivated the establishment of
nutrient criteria for streams, lakes, and estuaries as a means to protect aquatic resources. Nutrient criteria have been established
based on ecoregional differences, recognizing that geographic variation in climate, topography, geology, and land use require
use of different criteria values for different regions of the continental United States. Several studies have demonstrated
that land-cover composition also strongly influences nutrient concentrations and yields. We examined the relative importance
of ecoregions and watershed land-cover composition in explaining variability in nitrogen (N) and phosphorus (P) concentrations
by re-analyzing the National Eutrophication Survey (NES) data reported by Omernik (1977). The variance of N concentrations
among land-cover composition classes within ecoregions was six times larger than the variance among ecoregions. For P concentrations,
land-cover composition within ecoregions accounted for three times more variance than ecoregions themselves. Variance across
ecoregions was only weakly significant after accounting for variance in land-cover composition within ecoregions. The results
suggest that the relationship between land-cover composition and nutrient concentrations in aquatic systems should also be
used to help guide establishment of nutrient criteria. 相似文献
613.
Schurrer JA Dee SA Moon RD Rossow KD Mahlum C Mondaca E Otake S Fano E Collins JE Pijoan C 《American journal of veterinary research》2004,65(9):1284-1292
OBJECTIVE: To determine whether flies can acquire porcine reproductive and respiratory syndrome virus (PRRSV) and disperse the virus throughout a designated area. ANIMALS: 60 four-month-old pigs. PROCEDURE: On day 0, 28 of 60 pigs were inoculated with PRRSV MN 30-100 (index variant). On the same day, 100,000 pupae of ochre-eyed houseflies and 100,000 pupae of red-eyed (wild-type) houseflies were placed in the swine facility for a release-recapture study. Flies were recaptured at 2 locations within the swine facility, 6 locations immediately outside the facility, and 30 locations 0.4, 0.8, 1.3, 1.7, 1.9, and 2.3 km from the facility. Traps were emptied on days 2, 7, 8, 10, and 14. Samples derived from flies were tested by use of a polymerase chain reaction assay, virus DNA was sequenced, and viruses were tested for infectivity by means of a swine bioassay. RESULTS: PRRSV RNA homologous to the index PRRSV was detected in trapped flies collected inside and immediately outside the facility and from 9 of 48 samples collected at 0.4 km, 8 of 24 samples collected at 0.8 km, 5 of 24 samples collected at 1.3 km, and 3 of 84 samples collected at > 1.7 km from the facility. Two samples collected at 0.8 km contained genetically diverse variants of PRRSV. Swine bioassays revealed the virus in flies was infectious. CONCLUSIONS AND CLINICAL RELEVANCE: Flies appeared to become contaminated with PRRSV from infected pigs and transported the virus > or = 1.7 km. Fly-born transmission may explain how PRRSV is seasonally transported between farms. 相似文献
614.
OBJECTIVE: To report the use of dorsal acetabular augmentation (DAA) in canine total hip arthroplasty (THA) and to evaluate the clinical and radiographic outcome after a minimum of 1 year follow-up. STUDY DESIGN: Clinical study. ANIMALS: Nine dogs that had THA. METHODS: Ten hips requiring acetabular augmentation for optimum acetabular cup implantation for THA were evaluated retrospectively. The excised femoral head and neck was used as the corticocancellous bone graft for index THA surgeries, and the dorsal crest of the ipsilateral ilial wing was used as the bone graft in 1 dog that had a revision surgery. Clinical and radiographic follow-up examinations were performed at approximately 8 weeks and 1 year postoperatively. Long-term radiographic examinations included use of a standing dorsal acetabular rim (DAR) projection for assessment of graft-recipient boundary. Functional clinical outcome was assessed using direct patient evaluation and telephone interview. RESULTS: One dog failed to regain limb function after surgery. Suspected aseptic loosening of the acetabular cup was observed on radiographs approximately 12 weeks postoperatively. Excluding this single explantation, follow-up physical and radiographic examinations indicated good implant and graft positioning and normal function for all dogs. CONCLUSIONS: Acetabular augmentation permitted implantation of an appropriately sized acetabular cup while maintaining complete DAR coverage of the prosthesis. Nine out of 10 hips had a successful outcome with minimal radiographic and no functional abnormalities. Further follow-up is necessary to determine the long-term outcome of DAR augmentation in canine THA. CLINICAL RELEVANCE: Acetabular augmentation with an autogenous corticocancellous bone graft constructed from the femoral head and neck can provide complete DAR coverage to permit use of an appropriately sized acetabular cup in THA. 相似文献
615.
616.
Long-term degeneration and regeneration of the rabbit facial nerve blocked with conventional lidocaine and bupivacaine solutions 总被引:2,自引:0,他引:2
Gözil R Kurt I Erdoğan D Calgüner E Keskil S Kurt MN Elmas C 《Anatomia, histologia, embryologia》2002,31(5):293-299
The alterations due to the long-term degeneration and regeneration of the rabbit facial nerve were investigated. The facial nerve was blocked with conventional lidocaine and bupivacaine solutions. The rabbits were sacrificed and facial nerves were removed 2, 4, 6 and 8 weeks after the administration of normal saline, lidocaine and bupivacaine. The samples were then processed for electron microscopic observation. Degenerations were seen 2-4 weeks after the injection of normal saline, lidocaine and bupivacaine. In the normal saline group the regeneration process was observed after 6 weeks, whereas in the lidocaine and bupivacaine groups this process was first noticed after 8 weeks. In the lidocaine and bupivacaine groups, regeneration was not completed at the end of 8 weeks; however, it was faster in the bupivacaine group. Bupivacaine is therefore suggested as the drug of choice for neural blockade as it caused less damage and a faster regeneration. 相似文献
617.
Mechanism-based diagnostic reasoning: thoughts on teaching introductory clinical pathology 总被引:1,自引:0,他引:1
Bender HS Lockee BB Danielson JA Mills EM Boon GD Burton JK Vermeer PJ Zimmerman KL Hilmer KM 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2000,29(3):77-83
Abstract: Teaching introductory clinical pathology to veterinary students is a challenging endeavor that requires a shift in learning strategies from rote memorization to diagnostic reasoning. Educational research has identified discrete cognitive stages required to achieve the automated, unconscious thinking process used by experts. Building on this knowledge, we developed a case-based approach to clinical pathology instruction that actively engages students in the learning process and links performance with positive reward. Simulated cases provide context and create a structure, or "schema", which enhances the learning process by enabling students to synthesize facts and link them with their causal mechanism to reach a defensible diagnostic conclusion. Web-based tools, including the "Problem List Generator" and tutorials, have been developed to facilitate this process. Through the collaborative Biomedical Informatics Research Group, we are working to further develop and evaluate Web-based instructional tools and new educational methods, to clarify the diagnostic reasoning processes used by experienced clinical pathologists, and, ultimately, to better educate our future students to be effective diagnosticians. 相似文献
618.
George Holan Wynona M. P. Johnson Kurt Rihs Christopher T. Virgona 《Pest management science》1984,15(6):637-641
A novel group of oxime O-ether insecticides was tested on the labellar taste receptors of the blowfly Lucilia cuprina. Some of the compounds failed to elicit any response at the receptor, while the neurophysiologically active compounds generated multiple nerve spikes similar to DDT. The insect toxicities of all the oxime O-ethers were tested by topical application on the same strain of blowfly. The relationships between structure, index of multiplicity and LD50 values are discussed. 相似文献
619.
620.