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951.
Actinomyces endophthalmitis and pneumonia were diagnosed in a young rottweiler that was presented with lethargy, weight loss, right blepharospasm, and ocular discharge. The affected eye was enucleated, and the pneumonia was treated successfully with systemic antibiotics.  相似文献   
952.
953.
OBJECTIVE: To determine the efficacy of long-term enalapril administration in delaying the onset of congestive heart failure (CHF). DESIGN: Placebo-controlled, double-blind, multicenter, randomized trial. ANIMALS: 124 dogs with compensated mitral valve regurgitation (MR). PROCEDURES: Dogs randomly assigned to receive enalapril or placebo were monitored for the primary endpoint of onset of CHF for < or = 58 months. Secondary endpoints included time from study entry to the combined endpoint of CHF-all-cause death; number of dogs free of CHF at 500, 1,000, and 1,500 days; and mean number of CHF-free days. RESULTS: Kaplan-Meier estimates of the effect of enalapril on the primary endpoint did not reveal a significant treatment benefit. Chronic enalapril administration did have a significant benefit on the combined endpoint of CHF-all-cause death (benefit was 317 days [10.6 months]). Dogs receiving enalapril remained free of CHF for a significantly longer time than those receiving placebo and were significantly more likely to be free of CHF at day 500 and at study end. CONCLUSIONS AND CLINICAL RELEVANCE: Chronic enalapril treatment of dogs with naturally occurring, moderate to severe MR significantly delayed onset of CHF, compared with placebo, on the basis of number of CHF-free days, number of dogs free of CHF at days 500 and study end, and increased time to a combined secondary endpoint of CHF-all-cause death. Improvement in the primary endpoint, CHF-free survival, was not significant. Results suggest that enalapril modestly delays the onset of CHF in dogs with moderate to severe MR.  相似文献   
954.
The rural mixed-animal veterinarian is a critical control point for safe, wholesome, affordable food production and security. The population of students entering food-animal practice is decreasing, and future shortages are likely. Veterinary practice owners will continue to struggle to find associates to fill open positions. Identifying and hiring the correct veterinarian for an open position is a challenging proposition for the rural practitioner. Kansas State University hosted a forum to facilitate the hiring process and provide education regarding the mechanism of an effective selection interview. A unique experiential technique known as "speed interviews" was used to facilitate communication between conference participants and to practice newly acquired skills. A survey of participants revealed similar viewpoints toward most job attributes. Veterinary students and prospective employers expressed realistic expectations of job requirements, salaries, and debt load. Students expressed willingness to work and desire to practice in the types of practices defined by the veterinarians. The symposium provided valuable insight for practitioners and students regarding the recruitment process. Appropriate and accurate representation at the time of job/associate selection is critical for long-term success and employee retention. The goal of the event was to provide a service to both prospective employers and students by offering education regarding the employment selection interview process and placing attendees in an environment rich with people who have complimentary goals.  相似文献   
955.
Zeins, which comprise the majority of proteins in corn, are located in spherical organelles called protein bodies. Changes in protein body shape and release of encapsulated α-zeins as a result of cornflake processing (conventional pressed or extrusion flaking) were investigated. Size-exclusion chromatography, SDS-PAGE, and protein solubility tests showed that, upon cooking, zein proteins form large, disulfide-bound polymers, many of which were insoluble in nonreducing solvents. Transmission electron microscopy with immunogold staining revealed that cooking had no effect on protein body structure in corn, but after processing to cornflakes, protein body structure was altered. In conventional pressed cornflakes, the protein bodies were flattened, partially fused together, and α-zeins were to some degree released, whereas in the extruded flakes, protein bodies were completely disrupted and α-zeins dispersed. These results suggest that zeins in cornflakes, particularly extruded ones, are not confined to rigid protein bodies but can interact with each other and other components in the system. The disruption of protein bodies, zein release, and the chemical changes that proteins undergo during processing are speculated to be determinants of texture in ready-to-eat corn-based breakfast cereals.  相似文献   
956.
At the core of an integrated pest management program for Pennsylvanian apple orchards is an integrated mite management program that is based on a natural enemy, the coccinellid Stethorus punctum punctum (LeConte). The program relies upon the principles of ecological selectivity (e.g. chemical selection, timing, dose and method of application) for the organophosphate and carbamate insecticides. During the last 20 years the tufted apple bud moth (TABM), Platynota idaeusalis (Walker), a direct pest of apple, has developed resistance to these two chemical classes. In an effort to address this growing resistance problem, an intensive research program was initiated in 1986 on how to manage insecticide resistance in TABM while preserving the integrity of the integrated mite management program. One aspect of this research program is the investigation of biochemical and genetic approaches to resistance, including an analysis of detoxification mechanisms, effects of host plant allelochemistry on resistance and detoxification enzyme activities, reversion, gene flow and the isolation and characterization of a gene for glutathione transferase from TABM. Management approaches that have been developed and successfully implemented include pheromone mating disruption, parasitoids, ground-cover management including insecticides, Bacillus thuringiensis Berl. products and insect growth regulators. Resistance management options for TABM are presented. ©1997 SCI  相似文献   
957.
958.
Specific gravity of potato tubers provides an estimate of starch content of which uniformly high levels are important for product quality. The objectives of this study were to document the relationship between the level of specific gravity and the variability among tubers and to model the seasonal development o f specific gravity for seven potato clones. Individual determinations were made on twenty tubers from each plot using the weight-in-air, weight-in-water method on each of eight harvest dates spanning the tuber growth period. For each plot, the mean and standard deviation of specific gravity were calculated and used to define the correlation between specific gravity level and tuber-to-tuber variability and to construct a predictive model of the seasonal specific gravity developmental pattern. As the season progressed, tuber-to-tuber variability of specific gravity increased for some clones but not for others. A positive correlation existed between tuber specific gravity mean and its standard deviation for four of the seven clones in 1991 and five in 1992. Correlation coefficients were generally low, suggesting only a weak association between specific gravity and its standard deviation. Tuber specific gravity developed in a similar seasonal pattern for the seven clones. It generally started low, reached a maximum approximately seven to eleven weeks after tuberset, at which time some clones showed a tendency to decline through the remainder of the season. Quadratic regression equations provided an adequate model to describe specific gravity development for all seven clones over the tuber growth period. Statistical contrasts were used to test for differences in equation parameters, including line coincidence, line slope, and intercept. The model showed that initial specific gravity level at tuber set, the rate of early season increase, as well as the length of time from tuber set to specific gravity maximum, varied by clone and determined the level of specific gravity at season’s end.  相似文献   
959.
Flours from eight sorghum cultivars were evaluated for their couscous-making ability with the objective of finding predictive relationships between flour physicochemical properties and couscous quality. Chemical composition, physical characteristics, and pasting and gelatinization properties of the flours were determined. A laboratory procedure was used to prepare couscous. Couscous properties were evaluated and compared to a laboratory-prepared and a commercial durum wheat couscous. Hard grain produced flours containing a high proportion of coarse particles with low ash and high damaged starch content and yielded a higher proportion of desirable sorghum couscous granules. A variety of colors ranging from brown to yellow were obtained when flours were processed into couscous. Cooked sorghum couscous stickiness was positively correlated (r = 0.89, P < 0.01) with the amount of damaged starch in flour. Cooked couscous hardness correlated positively (r = 0.79, P < 0.05) with apparent amylose content of flour and correlated negatively (r = -0.75, P < 0.05) with flour peak viscosity. Durum wheat couscous was lighter and had more yellow color than sorghum couscous. Sorghum couscous was stickier and harder than durum wheat couscous. Addition of 2% oil to the cooking water considerably improved the texture of some sorghum couscous to a level comparable to that of durum wheat couscous.  相似文献   
960.
Changes in temperature, precipitation, and atmospheric carbon dioxide (CO2) concentration that are expected in the coming decades will have profound impacts on terrestrial ecosystem net primary production (NPP). Nearly all models linking forest NPP with soil carbon (C) predict that increased NPP will result in either unchanged or increased soil C storage, and that decreased NPP will result in decreased soil C storage. However, linkages between forest productivity and soil C storage may not be so simple and direct. In an old-growth coniferous forest located in the H.J. Andrews Experimental Forest, OR, USA, we experimentally doubled needle litter inputs, and found that actual soil respiration rates exceeded those expected due to the C added by the extra needles. Here, we estimated that this ‘priming effect’ accounted for 11.5–21.6% of annual CO2 efflux from litter-amended plots, or an additional 137–256 g C m−2 yr−1 loss of stored C to the atmosphere. Soil priming was seasonal, with greatest amounts occurring in June–August coincident with peaks in temperature and dry summer conditions. As a result of priming, mineral soil was more resistant to further mineralization during laboratory incubations. Soil lignin-derived phenols in the Double Litter plots were more oxidized than in the control, suggesting that the soil residue was more degraded. Our hypothesis that excess dissolved organic C produced from the added litter provided the link between the forest floor and mineral soil and a substrate for soil priming was not supported. Instead, the rhizosphere, and associated mycorrhizal fungi, likely responded directly to the added aboveground litter inputs. Our results revealed that enhanced NPP may lead to accelerated processing of some stored soil C, but that the effects of increased NPP on ecosystem C storage will be based on a net balance among all ecosystem C pools and are likely to be ecosystem-dependant. Forest C models need to include these complex linkages between forest productivity and soil C storage.  相似文献   
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