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821.
Rebecca K Muilenburg Thomas R Fry 《Veterinary Clinics of North America: Small Animal Practice》2002,32(4):839-849
In summary, an ideal diagnostic plan for cats with suspected FNPs should include a thorough anesthetized oropharyngeal examination, otoscopic examination, and imaging studies, which may consist of a bulla radiographic series or specialized imaging studies such as CT or MR scans. In general, if signs indicative of otitis media are present, ventral bulla osteotomy should be advised. As a result of the distinct appearance of FNPs, a preoperative biopsy is not indicated in all instances but should be considered if there are atypical features to the history or presentation. Traction-avulsion of polyps through the external ear canal or auditory tube from the oropharynx may have a lower success rate than traction-avulsion combined with ventral bulla osteotomy. If the veterinarian opts to treat FNPs by traction-avulsion alone as a result of financial constraints imposed by the client, the client should be strongly cautioned regarding potential recurrence. Postoperative complications are possible with any treatment option, but neurologic impairment, including Horner's syndrome, facial neuropathy, and hypoglossal neuropathy, is significantly more likely after surgical intervention by ventral bulla osteotomy than after traction-avulsion alone. A high percentage of these complications are self-limiting. In all instances, appropriate culture and sensitivity and biopsy specimens should be collected so as to enable provision of appropriate postoperative care. Antibiotic therapy should be provided based on culture and sensitivity test results. The use of postoperative steroids to prevent recurrence is controversial. 相似文献
822.
Sorensen KC Newman RG Kitchell BE Schaeffer DJ Siegel AM 《American journal of veterinary research》2005,66(9):1526-1535
OBJECTIVE: To isolate and characterize the cDNA sequence of canine stromelysin-1 (matrix metalloproteinase [MMPI-3), screen various naturally developing primary tumors of dogs, and assess the effect of stromelysin-1 on survival of dogs with cancer. SAMPLE POPULATION: 3 canine cell lines and biopsy specimens of primary tumors collected from 54 dogs. PROCEDURE: 3 canine cell lines and biopsy specimens of primary tumors collected from 54 dogs at the University of Illinois Veterinary Teaching Hospital were used in the study. Primer sets based on human stromelysin-1 and consensus sequences were designed for expression, screening, and isolation. Two additional primer sets were designed for screening. Samples were assayed at least in duplicate. Data were analyzed for differences in expression of stromelysin-1 on the basis of sex, age, metastasis, malignant versus nonmalignant tissue origin, and duration of patient survival. RESULTS: A 1,479-bp cDNA nucleotide sequence was amplified from established canine cell lines. The open reading frame encoded a protein consisting of 478 amino acids. This sequence was 70% to 88% homologous with stromelysin-1 of other species at the amino acid level. Fifty-four samples were screened for stromelysin-1. Of these, 34 (63%) had positive results and 20 (37%) had negative results for expression. Stromelysin-1 and metastasis were associated with a poor prognosis for survival. CONCLUSIONS AND CLINICAL RELEVANCE: Stromelysin-1 is a potential activator of other members of the MMP family. Additional studies are needed to investigate the relationship between stromelysin-1 production and aggressive biological behavior of tumors in dogs. 相似文献
823.
Adamo PF Crawford JT Stepien RL 《Journal of the American Animal Hospital Association》2005,41(6):400-405
An 8-year-old, spayed female Dalmatian with a history of seizures was evaluated for cervical pain and bilateral scleral hemorrhages. Diagnostic evaluations revealed a mass displacing the ventral brainstem on magnetic resonance imaging (MRI). The mass was surgically removed and histologically confirmed to be a hematoma. The dog's neurological signs resolved completely after surgery. Although extradural, subdural, subarachnoid, and intraparenchymal hemorrhages have been reported in dogs and cats, this is the first known report of a subdural hematoma of the ventral brainstem in a dog. On the basis of the history and the appearance of the subdural hematoma on MRI, a traumatic event during the seizure episodes was considered the most likely cause of the subdural hematoma in this case. 相似文献
824.
Modeling spatial and temporal transmission of foot-and-mouth disease in France: identification of high-risk areas 总被引:1,自引:0,他引:1
Le Menach A Legrand J Grais RF Viboud C Valleron AJ Flahault A 《Veterinary research》2005,36(5-6):699-712
Foot-and-mouth disease is one of the most contagious diseases of animal livestock. We used statistical tools to explore the dynamics of epidemics and to evaluate the consequences of virus reintroduction in France. We developed a stochastic farm-based model adapted to the French farm structure from previous modeling works following the 2001 epidemic in the United Kingdom. This model depends upon the distance between the 280,000 French farms and on species type (e.g. cows and sheep) and it tracks each animal's farm status at any given day. Since data were only available at the town scale, the farm location and the number of animals in each farm were simulated over the surface area of each French town, as well as the number of mixed farms. Based on 200 simulations of the model, our results allowed for the study of local disease transmission, since it begins simulations once limitation of movement is put into place. On average, the same 50 randomly chosen initially infected farms would lead to 1,110 infected farms (610; 1,590) when two control strategies (culling within 0.5 km from an infected farm and vaccination within 3 km) are put into place. Regions with high densities of cows and sheep (e.g. Pays-de-la-Loire) are high-risk zones, confirming that the epidemic process depends upon the location and the type of initially infected farms (size, species type). The results of this model highlight the importance of Geographical Information Systems (GIS) to obtain more precise data concerning herds. 相似文献
825.
PURPOSE: To investigate the role of pigment dispersion and inflammation in the pathogenesis of goniodysgenesis-related glaucoma (GDRG). PROCEDURES: Cases of GDRG were selected when the duration of the disease was specified and there was not any confounding pathology. Cases were grouped into < or = 7-day (acute), and > 7-day (chronic) durations, based on the time required to effect end-stage retinal damage. Acute cases were further divided into < 4-day and 4-7-day groups to assess peracute changes. Slides were evaluated for four individual signs of pigment dispersion: segmental loss of posterior iris pigment epithelium, clumping of posterior iris pigment epithelium, pigmented cells in the trabecular meshwork or anterior chamber and preferential settling of pigmented cells in the ventral aspect of the iridocorneal angle. Slides were also evaluated for the presence of neutrophils and/or lymphoplasmacytic cells in the trabecular meshwork (TM). Differences between groups were analyzed statistically. RESULTS: Of 100 cases evaluated, 34 were < or = 7-days (acute) (14 < 4-day and 20 4-7-day) and 66 were > 7-days (chronic) in duration. Of all globes examined, 96% had at least one sign of pigment dispersion, with no significant difference between groups. Two or more signs of pigment dispersion were present in 76% of all globes. The 4-7-day group was significantly more likely than the < 4-day group to have at least two signs. The difference was not significant between < or = 7- and > 7-day groups. Neutrophils were present in the TM of 86% of < 4-day and 50% of 4-7-day cases. Cases in the < or = 7-day group were significantly more [corrected] likely than > 7-day cases to have neutrophils in the TM, with 65% and 17% [corrected] positive cases, respectively. Lymphoplasmacytic inflammation was present in 53% of all cases, with no significant difference between groups. Cases in the < or = 7-day group were significantly more likely than > 7-day cases to have both types of inflammation. CONCLUSIONS: Our results indicate that both acute inflammation and pigment dispersion may be key factors in the pathogenesis of GDRG. Pigment dispersion is prevalent at all time points and increases during the first 7 days. The finding of iris pigment epithelial loss supports the theory that pupillary block associated with iris-lens touching may be important in the pathogenesis of GDRG. 相似文献
826.
Gilmour MA Clarke CR Macallister CG Dedeo JM Caudell DL Morton RJ Pugh M 《Veterinary ophthalmology》2005,8(5):331-335
OBJECTIVE: To investigate intraocular penetration of orally administered doxycycline in the normal equine eye and to compare intraocular and serum doxycycline concentrations. Procedures Six mares were administered doxycycline at 10 mg/kg every 12 h by nasogastric tube for 5 days. Blood, aqueous, and vitreous samples were collected on days 1 and 5. All samples were assayed for doxycycline concentrations. Aqueous and vitreous samples were also assayed for protein quantitation. RESULTS: Doxycycline was rapidly absorbed after the first dose (T(max) value of 1.42 +/- 1.28 h); and elimination of doxycycline occurred slowly (median t(1/2) = 10.88 h). Doxycycline could not be detected in the aqueous on days 1 and 5, nor could it be detected in the vitreous on day 1. On day 5, the mean vitreous doxycycline concentration was 0.17 +/- 0.04 microg/mL at 2 h after drug administration. CONCLUSIONS: Repeated oral administration of doxycycline in the horse resulted in steady state serum concentrations of < 1 microg/mL; however, it did not result in appreciable concentrations of drug in the aqueous and vitreous in normal eyes. 相似文献
827.
William W.?HargroveEmail author Forrest M.?Hoffman Rebecca A.?Efroymson 《Landscape Ecology》2005,20(4):361-373
We describe the Pathway Analysis Through Habitat (PATH) tool, which can predict the location of potential corridors of animal
movement between patches of habitat within any map. The algorithm works by launching virtual entities that we call `walkers'
from each patch of habitat in the map, simulating their travel as they journey through land cover types in the intervening
matrix, and finally arrive at a different habitat `island.' Each walker is imbued with a set of user-specified habitat preferences
that make its walking behavior resemble a particular animal species. Because the tool operates in parallel on a supercomputer,
large numbers of walkers can be efficiently simulated. The importance of each habitat patch as a source or a sink for a species
is calculated, consistent with existing concepts in the metapopulation literature. The manipulation of a series of contrived
artificial landscapes demonstrates that the location of potential dispersal corridors and relative source and sink importance
among patches can be purposefully altered in expected ways. Finally, potential dispersal corridors are predicted among remnant
woodlots within three actual landscape maps.
The U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged. 相似文献
828.
Cebra CK Tornquist SJ Jester RM Stelletta C 《American journal of veterinary research》2004,65(7):996-1001
OBJECTIVE: To assess the effects of prolonged feed deprivation on glucose tolerance, insulin secretion, and lipid homeostasis in llamas. ANIMALS: 9 adult female llamas. PROCEDURE: On each of 2 consecutive days, food was withheld from the llamas for 8 hours. Blood samples were collected before and 5, 15, 30, 45, 60, 120, and 240 minutes after IV injection of dextrose (0.5 g/kg) for determination of plasma insulin and serum glucose, triglyceride, and nonesterified fatty acid concentrations. Between experimental periods, the llamas received supplemental amino acids IV (185 mg/kg in solution). The llamas were then fed a limited diet (grass hay, 0.25% of body weight daily) for 23 days, after which the experimental procedures were repeated. RESULTS: Feed restriction decreased glucose tolerance and had slight effects on insulin secretion in llamas. Basal lipid fractions were higher after feed restriction, but dextrose administration resulted in similar reductions in serum lipid concentrations with and without feed restriction. Insulin secretion was decreased on the second day of each study period, which lessened reduction of serum lipid concentrations but did not affect glucose tolerance. CONCLUSIONS AND CLINICAL RELEVANCE: Despite having a comparatively competent pancreatic response, feed-restricted llamas assimilated dextrose via an IV bolus more slowly than did llamas on full rations. However, repeated administration of dextrose reduced insulin secretion and could promote hyperglycemia and fat mobilization. These findings suggested that veterinarians should use alternative methods of supplying energy to camelids with long-term reduced feed intake or consider administering agents to improve the assimilation of glucose. 相似文献
829.
Kania SA Williamson NL Frank LA Wilkes RP Jones RD Bemis DA 《American journal of veterinary research》2004,65(9):1265-1268
OBJECTIVE: To determine the methicillin-resistant profile of staphylococcal isolates from the skin of dogs with pyoderma. ANIMALS: 90 dogs with pyoderma. PROCEDURE: Staphylococci isolated from dogs with pyoderma were tested for susceptibility to methicillin by use of a standard disk diffusion test with oxacillin disks. The DNA extracted from the isolates was tested for the mecA gene that encodes the penicillin-binding protein 2a (PBP2a) by use of a polymerase chain reaction (PCR) assay. The expression of PBP2a was determined with a commercial latex agglutination assay. Species of staphylococcal isolates were identified by use of morphologic, biochemical, and enzymatic tests. RESULTS: Most of the isolated staphylococci were methicillin-susceptible, coagulase-positive Staphylococcus intermedius isolates. Whereas only 2 of 57 S. intermedius isolates were resistant to methicillin, approximately half of the isolates had the mecA gene and produced PBP2a. Staphylococcus schleiferi was the second most common isolate. Widespread resistance to methicillin was found among S. schleiferi isolates. More coagulase-negative S. schleiferi isolates were identified with mecA gene-mediated resistance to methicillin, compared with coagulase-positive S. schleiferi isolates. CONCLUSIONS AND CLINICAL RELEVANCE: The latex agglutination assay for the detection of PBP2a expression coupled with the PCR assay for the mecA gene may provide new information about emerging antimicrobial resistance among staphylococcal isolates. 相似文献
830.
Knowles RJ Curtis TM Crowell-Davis SL 《American journal of veterinary research》2004,65(11):1548-1556
OBJECTIVE: To determine whether the direction of dominance as determined by agonistic interactions away from food was different from the direction of dominance as determined by access to a resource in cats. ANIMALS: 28 cats. PROCEDURE: Dyadic relationships and hierarchy formed from observation of agonistic interactions away from food were compared with those formed from interactions at the food bowl. A cat was scored as subordinate to another cat if it lost 3 of 3 interactions or lost > or = 75% of the interactions when > 3 interactions occurred. RESULTS: Cats were observed for 449.4 hours. Hierarchy rank determined by agonistic interactions away from food was significantly correlated with rank determined by interactions at the food bowl. In 27 of 31 dyads, the direction of dominance was the same for food bowl and agonistic relationships, which was significant. In post hoc analyses, when considering the relationship between 2 cats, the heavier cat most likely ranked higher in each hierarchy; however, age was not significantly correlated with either hierarchy. On the basis of dyadic information, the older cat in a dyad was more often dominant in agonistic interactions. Males had a higher mean dominance rank than females; however, sex had no effect on rank determined by interactions at the food bowl. CONCLUSIONS AND CLINICAL RELEVANCE: Factors influencing dominant-subordinate relationships are of interest for understanding and treating behavior problems such as aggression and resource control. The outcome of agonistic interactions away from food was related to, but not perfectly correlated with, the outcome of interactions at the food bowl, although winners of those agonistic interactions tended to have control of food. 相似文献