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71.
A. Hayes V. Adams K. Smith G. Maglennon S. Murphy 《Veterinary and comparative oncology》2007,5(3):168-176
The effect of treatment with vinblastine and prednisolone chemotherapy in dogs undergoing only surgical excision of Patnaik grade III cutaneous mast cell tumours is reported. Potential explanatory variables were explored using Kaplan–Meier survival analysis with log‐rank tests. During a median follow‐up period of 429 days, the overall median survival time (MST) was not reached (lower 95% CI = 322 days). The 1‐year survival probability was 0.71 (standard error 0.1), remaining unchanged at 2 years. Secondary disease at presentation was an independent risk factor for survival (P= 0.045). The MST of dogs presenting with secondary disease was 322 days, with a lower 95% confidence interval of 142 days and a 1‐year survival of probability of 0.47 (standard error 0.19). Adverse effects were recorded in 6 of the 108 (5.6%) vinblastine doses given. This chemotherapy regimen is a well‐tolerated adjunct to surgery for grade III mast cell tumours and appears to prolong survival compared with that expected with surgery alone. 相似文献
72.
ABSTRACT The pathogens causing perennial canker of peach, Leucostoma spp., were characterized in Michigan orchards to identify which species and subgroups (cryptic species) were prevalent on a highly susceptible peach cultivar, Loring, and a less susceptible cultivar, Redhaven. Four hundred and three strains of Leucostoma were isolated from cankers in three southwest Michigan orchards where 'Loring' occurred adjacent to 'Redhaven' in side-by-side plots. Based on colony morphology and small nuclear rDNA size polymorphisms, three cryptic species were detected; 89% of the isolates were identified as L. persoonii phenetic group 1, 10% were L. cincta group 4, and 1% were L. persoonii group 2. Pathogen profiles differed significantly between cankers on small branches of 'Loring' and 'Redhaven', and between cankers on small branches and trunks. Of 1,232 random pairings among isolates of L. persoonii group 1, 95% were vegetatively incompatible. A minimum of 11 and a maximum of 17 maternal lines were identified based upon mitochondrial DNA restriction fragment length polymorphisms among 69 isolates of L. persoonii group 1 from one split-cultivar block of 72 trees. Vegetative compatibility loci were randomly associated with maternal lines. Evidence of clonality was absent in L. persoonii group 1, as no correlation occurred between these two sets of independent genetic markers and no genotype was over-represented. The number of cryptic species, the number of maternal lines, and the frequency of incompatibility within maternal lines indicate that considerable genetic variation exists within the Leucostoma populations in Michigan peach orchards, and that sexual recombination is common. 相似文献
73.
Paul Y. Barthez DVM William J. Hornof DVM MS Larry D. Cowgill DVM PhD Larry A. Neal BS Paul Mickel 《Veterinary radiology & ultrasound》1998,39(5):470-474
The scintigraphically measured percentage dose uptake of 99m Tc-DTPA by the kidneys and the plasma clearance of 99m Tc-DTPA have been reported to correlate well with inulin clearance. These two parameters were evaluated in seven dogs with known or suspected naturally occurring renal disease and compared to simultaneously measured renal inulin clearance. Correlation between inulin clearance and the 99m Tc-DTPA plasma clearance was better ( p =.0016) than the correlation between the percentage DTPA uptake by the kidney. It was concluded that measurement of 99m Tc-DTPA plasma clearance is a more accurate method to estimate global glomerular filtration rate (GFR) than the percentage kidney uptake. 相似文献
74.
A serum viral inhibitor (SVI) was isolated from goats and partially characterized. The inhibitor prevented the cytopathic effects of vesicular stomatitis virus, encephalomyocarditis virus, and a caprine herpesvirus, indicating broad antiviral activity. The SVI was distinct from interferon because SVI did not induce an antiviral state in cells (ie, lack of protection of SVI-treated cells from virus challenge). The SVI had activity on heterologous cells, including human, bovine, and ovine cells. The lack of antiviral activity in mouse cells indicated that SVI was not an antibody. Like fibroblast interferon, however, SVI was sensitive to trypsin, was acid stable at pH 2 and 4 C for 4 days, was heat stable at 56 C for 1 hour, and could not be sedimented by centrifugation at 100,000 X g for 4 hours. 相似文献
75.
76.
Using phenotypic variation to determine conservation value: application of a novel approach to Arctic charr 总被引:1,自引:1,他引:0
Abstract – There is a very high degree of discrete variation in phenotype between populations of Arctic charr. This takes the form of variation not only in morphometric and meristic characters traditionally used to distinguish species, but also in characteristics of life-history, behaviour, coloration and ecology. This variability has a number of consequences, one of these is that there is a strong case for the conservation of populations with extreme phenotypes. However, if variation is discrete between populations but continuous across many populations, this poses difficulties in separating those populations of high conservation value from those of lower conservation value. In this paper we describe a statistical technique which enables populations on the extreme edges of the range of phenotypic variation to be identified and apply this to the morphometric characters of charr from 25 populations from across Scotland and Ireland. The technique enables the identification of any proportion of the most extreme phenotypes. When applied to our data, one population (Loch More) was in the top 2 percentile of the most extreme phenotypes from across the range of all populations included. Three populations were within the top 10% most extreme phenotypes (Lochs More, Uaine and Earn) and a further five within the top 20% (previously mentioned lochs plus Lochs Eck, Merkland, Uaine, Talla and Lough Nalughraman). This technique can potentially be used on any species and on any suite of characteristics as an objective measure of conservation value of a population within a continuous phenotypic range. 相似文献
77.
Larry G. Hansen Elizabeth M. Cozzi Robert L. Metcalf Terry K. Hansen 《Pesticide biochemistry and physiology》1985,24(1):136-148
The oxons of leptophos, its desbromo analog, and its ethoxy analog all inhibit hen brain neurotoxic esterase (NTE) to a similar degree in vitro, but have large differences in minimum effective oral doses for organophosphorus-induced delayed neurotoxicity. The potencies of leptophos and ethoxyleptophos are increased 10-fold when administered to hens intravenously (iv), but the potency of desbromoleptophos is nearly the same whether administered iv or po. Leptophos distributes nearly five times more rapidly from the central compartment than does desbromoleptophos, and its attenuated oral potency may be due to slower net absorption and/or dilution by compartments other than nervous tissue. Intravenously administered phenylphosphonothionates are excreted rapidly into the gastrointestinal tract and a large proportion of the dose is eliminated in the first 48 hr. Indirect evidence indicates that ethoxyleptophos is more rapidly degraded and ethoxyleptophos-inhibited NTE recovers more rapidly than does NTE inhibited by leptophos or desbromomleptophos. It is proposed that differential aging of ethoxyleptophos chiral isomers as well as pharmacokinetic factors may contribute to the apparently anomalous behavior of these three analogs. 相似文献
78.
Eight horses were allotted to 2 groups, each of 4 horses. All horses were given 100 plastic markers intragastrically via a nasogastric tube. One group of animals (control group) was not given medication after marker administration. The other group (test group) was given neostigmine methylsulfate (0.022 mg/kg of body weight) in the subcutaneous tissue at the time of marker administration and 30, 60, and 90 minutes later. All horses were killed 135 minutes after marker administration to locate the beads in the gastrointestinal tract. Gastric emptying of the markers was significantly delayed (P less than 0.05) in horses given neostigmine methylsulfate. 相似文献
79.
Denise A. Elliott Richard W. Nelson Edward C. Feldman Larry A. Nea 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(3):161-165
Blood glycosylated hemoglobin (GHb) concentration was quantified in 84 healthy cats, 9 cats with stress-induced hyperglycemia, 37 cats with newly diagnosed diabetes mellitus, and 122 diabetic cats treated with insulin or glipizide. Diabetic control was classified as good or poor in insulin-treated or glipizide-treated cats based on review of history, physical examination findings, changes in body weight, and measurement of blood glucose concentrations. Blood GHb concentration was determined using an affinity chromatography assay. Mean blood GHb concentration was similar for healthy normoglycemic cats and cats with transient, stress-induced hyperglycemia, but was significantly (P < .001) higher in untreated diabetic cats when compared with healthy normoglycemic cats. Mean blood GHb concentration was significantly (P < .001) higher in 84 cats with poorly controlled diabetes mellitus when compared with 38 cats in which the disease was well controlled. Mean blood GHb concentration decreased significantly (P < .01) in 6 cats with untreated diabetes mellitus after insulin and dietary treatment. A similar significant (P < .01) decrease in mean blood GHb concentration occurred in 7 cats with poorly controlled diabetes mellitus after diabetic control was improved by an increase in insulin dosage from 1.1 ± 0.9 to 1.4 ± 0.6 U/kg/ 24 h and by feeding a diet containing increased fiber content and in 6 cats with transient diabetes mellitus 8.2 ± 0.6 weeks after discontinuing insulin treatment. There was a significant (P< .01) stress-induced increase in mean fasting blood glucose concentration and mean blood glucose concentration for 12 hours after administration of insulin or glipizide but no change in mean blood GHb concentration in 5 docile diabetic cats 12.2 ± 0.4 weeks after the cats became fractious as a result of frequent hospitalizations and blood samplings. Results of this study suggest that evaluation of blood GHb concentration may be a clinically useful tool for monitoring glycemic control of diabetes in cats. 相似文献
80.
Immune responsiveness and lymphoreticular morphology in cattle fed hypo- and hyperalimentative diets 总被引:1,自引:0,他引:1
Immune responses and lymphoreticular morphology were studied in 3 groups of yearling Hereford steers fed hypoalimentative, maintenance and hyperalimentative diets for 142 days. Significant decreases in plasma protein levels and circulating lymphocyte levels occurred in low energy intake steers. Percent circulating lymphocytes bearing surface immunoglobulins and serum levels of IgG and IgM did not vary significantly within or between groups. Antibody responses to Brucella abortus bacterin inoculated on day 63 were similar in all 3 groups. Antibody responses to chicken erythrocytes inoculated on day 88 were significantly lower in hypoalimentated steers. Differences between groups in lymphocyte blastogenic responses to phytohemagglutinin (PHA), concanavalin A (Con A) and pokeweed mitogen (PWM) were not significant. Hyperalimentated steers had significantly depressed PWM responses compared to a baseline value established for that group. In addition, hypoalimentated steers tended to have elevated responses to PHA, although differences were not significant. There were no significant differences between groups in dermal hypersensitivity responses to tuberculin following sensitization with viable Bacillus Calmette-Guerin (BCG). The thymuses of hypoalimentated steers were markedly atrophied but lymph nodes and splenic white pulp were normal. Thymus, lymph nodes and spleen were normal in hyperalimentated steers. 相似文献