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The purpose of this study was to evaluate the urogenital anatomy in female spayed dogs with and without signs of lower urinary tract disease by using conventional vaginourethrography, computed tomography (CT) vaginourethrography, and uroendoscopy. Nineteen dogs with lower urinary tract disease and 12 normal dogs were evaluated prospectively. Measurements made included vaginal length, vaginal height, vaginal width, vestibule length, vestibule height, vestibule width, vestibulovaginal ratios, cingulum height, cingulum width, cingulum area, urethral length, urethral height, urethral width, angle of urethra to vestibule, and angle of vaginal to vestibule. Group comparisons were made between dogs with and without lower urinary tract disease. Comparisons between conventional vaginourethrography and CT vaginourethrography were made when the same anatomical measurement was made by the 2 imaging modalities. There was no significant difference in all of the measurements (P > .01), including vestibulovaginal ratios and cingulum areas, between dogs with and without lower urinary tract disease. There was a larger proportion of dogs with a vestibulovaginal ratio <0.33 in normal dogs (8 of 12) compared with the clinical dogs (8 of 16). A significant difference between vestibulovaginal ratios or cingulum areas between dogs with and without lower urinary tract disease could not be identified. This suggests that a vestibulovaginal ratio of <0.33 may only be an incidental finding and the term "vestibulovaginal stenosis" may need to be redefined.  相似文献   
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Aeromonas hydrophila are known for being opportunistic pathogens, harboring various virulence factors and triggering lesions and death in fish. The disease caused by bacteria can make fish inappropriate for human consumption, besides representing a risk to public health. The pathogenesis can be influenced by environmental variables, affecting fish productivity and mortality. The present study aimed to determine whether A. hydrophila harbor the virulence genes aerolysin, hydrolipase, elastase, lipase, cytotonic enterotoxin (ast), lateral flagellum (laf), and polar flagellum (fla) and to evaluate the influence of environmental variables on in vitro growth, in vivo virulence and expression of some of these genes. Polymerase chain reaction (PCR)-based screening for the presence of these virulence genes was performed on 35 isolates. Six isolates containing different profiles of virulence genes were tested for in vitro growth under different conditions of pH, temperature, and ammonia and for in vivo virulence under these same environmental conditions. RT-qPCR was used to quantify the expression of aerolysin, lipase, and fla genes. All the tested environmental factors influenced the growth of A. hydrophila, while pH and ammonia concentrations influenced the bacterial virulence. The expression of the fla gene increased when bacteria were grown in higher ammonia concentration. The mortality established by Aeromonas is influenced by several environmental factors pinpointing the importance of its control in fish farming to avoid higher economic loses associated to bacterial disease outbreaks.  相似文献   
54.
Drug therapy is integral to emergency and critical care medicine but can also be the source of serious medical errors. There are important considerations with regard to drug, route, and interactions that require close attention in critical patients. The continuous development of new therapeutics and new information concerning current therapies requires practitioners to continually review drug therapies. This article addresses general guidelines, routes of administration, dosage calculations, interactions, monitoring recommendations, and resources available to help clinicians improve their drug therapy practices.  相似文献   
55.
Currently most dendritic cells (DC) for in vitro study are generated from bone marrow or peripheral blood by culture in high concentrations of GM-CSF and other cytokines. However, in mice it is also possible to generate DC from spleen cells using long-term stromal cell cultures. To determine whether tissue DC could be also be generated from cats, we established stromal cell cultures from a number of different tissues of newborn cats. We found that stromal cell cultures from spleen, lung, liver, kidney, brain, and lymph node tissues were all capable of spontaneously generating DC over long periods of time (months), without requiring the addition of exogenous cytokines. The tissue DC generated from these stromal cell cultures could be readily isolated at high purity by simple mechanical detachment. The feline tissue DC expressed high levels of CD11c, CD11b, and MHC Class II and variable levels of CD80 and CD14 and exhibited high levels of spontaneous macropinocytosis. Moreover, DC from spleen stromal cell cultures, but not DC from lung or liver stromal cell cultures, stimulated mixed-lymphocyte reactions. The DC generated from the stromal cell cultures were relatively independent of GM-CSF for survival and proliferation, indicative of a dependence on other growth factors produced by the stromal cells. These results suggest that tissues of young cats contain a population of resident DC progenitor cells that under appropriate conditions are capable of spontaneous proliferation and generation of immature DC.  相似文献   
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Objective To describe the long‐term histologic and intraocular pressure (IOP) lowering effects of diode laser transscleral cyclophotocoagulation (TSCP) on the normal equine eye. Animals Eight normal adult horses. Procedures TSCP was performed in one randomly assigned eye. Sixty spots were treated at settings of 1500 ms and 1500 mW. Two horses were randomly selected for euthanasia at 2, 4, 12, or 24 weeks post‐TSCP. Both eyes were enucleated and histologically evaluated. Intraocular pressure was measured by applanation tonometry prior to TSCP, immediately post‐TSCP, twice daily for 7 days post‐TSCP and then monthly until study conclusion. A longitudinal model estimated the average IOP values for the treated and untreated eyes at 1 week, 1, 3, and 6 months post‐TSCP. Results All treated eyes at all time periods exhibited four characteristic histologic lesions: scleral collagen hyalinization, ciliary body pigment dispersion and clumping, focal disruption of the ciliary body epithelium, and focal ciliary process atrophy. After TSCP, there were no significant changes in IOP from baseline for the control eyes, while the IOP in treated eyes was significantly decreased from baseline (P < 0.05) at all time periods. The estimated decrease in IOP in the treated eyes compared to baseline IOP at 6 months was ‐3.76 mmHg for an average decrease in IOP of 20% from baseline. Conclusion  Diode laser TSCP produces histologic lesions in the equine ciliary body that result in a significant and sustained decrease in IOP. TSCP may be an effective management for equine glaucoma.  相似文献   
58.
This study was designed to test the effect of antioxidant supplementation on feline immunodeficiency virus (FIV)-infected felines. Six acutely FIV-infected cats (> or =16 weeks post-inoculation) were given a propriety oral superoxide dismutase (SOD) supplement (Oxstrin; Nutramax Laboratories) for 30 days. Following supplementation, the erythrocyte SOD enzyme concentration was significantly greater in the supplemented FIV-infected group than the uninfected control group or the unsupplemented FIV-infected group. The CD4+ to CD8+ ratio increased significantly (0.66-0.88) in the SOD supplemented FIV-infected cats but not in the unsupplemented FIV-infected cats. Proviral load and reduced glutathione (GSH) levels in leukocyte cell types did not change significantly following supplementation. Antioxidant supplementation resulted in an increase in SOD levels, confirming the oral bioavailability of the compound in FIV-infected cats. This result warrants further investigation with trials of antioxidant therapy in FIV-infected cats that are showing clinical manifestations of their disease, as well as in other feline patients where oxidative stress likely contributes to disease pathogenesis, such as diabetes mellitus and chronic renal failure.  相似文献   
59.
The Global Oscillation Network Group (GONG) project estimates the frequencies, amplitudes, and linewidths of more than 250,000 acoustic resonances of the sun from data sets lasting 36 days. The frequency resolution of a single data set is 0.321 microhertz. For frequencies averaged over the azimuthal order m, the median formal error is 0.044 microhertz, and the associated median fractional error is 1.6 x 10(-5). For a 3-year data set, the fractional error is expected to be 3 x 10(-6). The GONG m-averaged frequency measurements differ from other helioseismic data sets by 0.03 to 0.08 microhertz. The differences arise from a combination of systematic errors, random errors, and possible changes in solar structure.  相似文献   
60.
ABSTRACT The germination of field-collected pseudosclerotia and the development of apothecia from eight New Jersey populations of the mummy berry fungus Monilinia vaccinii-corymbosi were evaluated under controlled conditions in the greenhouse. Development data for apothecia were used to describe the timing of apothecium formation and to estimate broad- and narrow-sense heritabilities of fungal phenology. Mean development times for the formation of apothecia ranged from 35.4 to 54.7 days. The mean development times for populations collected from early-season cv. Weymouth ranged from 35.4 to 39.6 days and were significantly shorter than the development times for three of the four populations collected from late-season cv. Jersey (46.9 to 54.7 days) or for the population collected from mixed stands of cultivated blueberries (42.7 days). The development of populations from late cultivars planted in very close proximity to early cv. Weymouth was early (36.5 to 39.0 days) and not significantly different from the development of populations collected from cv. Weymouth. Phenotypic and genetic variances of apothecium development for individual populations ranged from 18.9 to 44.8 and 7.2 to 30.9, respectively. Broad-sense heritabilities of apothecia development for each fungal population, calculated by partitioning phenotypic variation into genetic and environmental components, ranged from 0.31 to 0.78. Narrow-sense heritabilities of apothecia development, based on parent-offspring regression, ranged from 0.58 to 0.78. These results indicate that populations of M. vaccinii-corymbosi differ in phenology and that a significant portion of the phenological variation within populations is genetic. Thus, it is plausible to propose that the phenology of apothecium development is a component of fungal fitness and that host phenology can influence the timing of pathogen development.  相似文献   
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