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Hypersensitivities to foods afflict both dogs and cats. Clinical signs are highly variable, although pruritus is almost always present. Diagnosis and therapy are discussed.  相似文献   
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ABSTRACT The inheritance of resistance to aflatoxin production in corn (Zea mays) caused by the fungus Aspergillus flavus was studied following inoculation in progeny derived from the cross between the susceptible inbred B73 and the resistant inbred LB31. In 1993, the susceptible parent B73 (P(1)), resistant parent LB31 (P(2)), F(1), F(3), and BCP(1)-selfed generations were evaluated. In 1994, the study was expanded to include the F(2), BCP(1), and BCP(2) generations. Aflatoxin concentrations were higher in 1993 than 1994. Generation mean analysis showed that additive and dominant gene action were important for resistance to aflatoxin production. Potence ratios indicated dominance for resistance in both years. In 1993, aflatoxin values of the F(1) generation were significantly lower than the calculated mid-parent values, indicating dominant gene action favoring resistance. In 1994, values of the F(1) generation were not significantly lower than the calculated midparent value. The frequency distributions of aflatoxin values for families of the F(3) and BCP(1)-selfed generations were skewed toward the resistant parent, also indicating dominance. Heritability based on a progeny mean basis of F(3) families representing the additive variance plus one-fourth of the dominance variance was estimated at 66% over both years combined. Based on these results, selection for resistance to aflatoxin production in progeny derived from the cross between B73 and LB31 should be effective.  相似文献   
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Evoked cortical potentials and the numsber of flashes perceived were compared when subjects were presented with short trains of flashes under conditions where each presented flash could not be counted individually, but the train of flashes appeared to be flickering (1 to 14 flashes at 33.3 flashes per second). The rate at which each successive perceived flash was added appeared to correspond with the rate at which the successive components of the evoked response pattern were added. The temporal nature of this pattern was similar for both single flashes and trains of flashes. The results suggest that the onset of stimulation triggers a process whlich has a marked effect on both the cortical and perceptual response to subsequent stimulation.  相似文献   
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Current management of the grizzly bear (Ursus arctos) population in Yellowstone National Park and surrounding areas requires annual estimation of the number of adult female bears with cubs-of-the-year. We examined the performance of nine estimators of population size via simulation. Data were simulated using two methods for different combinations of population size, sample size, and coefficient of variation of individual sighting probabilities. We show that the coefficient of variation does not, by itself, adequately describe the effects of capture heterogeneity, because two different distributions of capture probabilities can have the same coefficient of variation. All estimators produced biased estimates of population size with bias decreasing as effort in creased. Based on the simulation results we recommend the Chao estimator for model M h be used to estimate the number of the female bears with cubs of the year; however, the estimator of Chao and Shen may also be useful depending on the goals of the research.  相似文献   
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An adult Bengal tiger (Panthera tigris tigris) housed in an outdoor sanctuary in Florida exhibited vomiting, diarrhea, and weight loss. A clinical workup did not reveal the source of the clinical signs and antibiotic therapy was unrewarding. Radiographs revealed the presence of an abdominal mass. The tiger died during an immobilization for a follow-up clinical examination. A necropsy was performed and tissue samples of intestine and mesenteric lymph nodes were submitted for histopathologic diagnosis. A pyogranulomatous panenteritis and lymphadenitis with intralesional hyphae led to a presumptive etiologic diagnosis of intestinal/abdominal pythiosis. The diagnosis of pythiosis was confirmed by serology and immunoblotting.  相似文献   
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Sapflow sensors were used to investigate variation in sapflow velocity at different positions in the sapwood of three-year-old Eucalyptus globulus ssp. globulus Labill. trees. Sapflow velocity was measured at 5-mm intervals across the sapwood by moving two probe sets simultaneously on two opposite radii. Another probe set placed in a fixed position at right angles to the first two sets acted as a control. A sapflow velocity ratio was defined as the velocity given by each moving sensor divided by that given by the static sensor. Correlation between observations of sapflow velocity at different positions exceeded 95%, and the ratio of velocity between any pair of sensors was constant. We observed radial variation in sapflow velocity across the sapwood with the lowest velocities at the center of the tree. Variation due to sensor position was high implying the need for large numbers of sensors for accurate estimates of sap flux. To overcome this need, we used a correction coefficient, namely a simple weighted average of the sapflow ratios with depth in the sapwood, for each fixed sensor. We recommend the use of three probe sets to estimate the correction coefficient. Subsequently, two probe sets can be placed at two fixed positions for routine measurements of sap flux.  相似文献   
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