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741.
742.
Immunofluorescence studies of canine distemper encephalitis on paraffin-embedded tissue. 总被引:1,自引:0,他引:1
A paraffin-embedding technique for fluorescent antibody studies of canine distemper encephalitis was developed. Specific fluorescence was demonstrated in all brain tissue from dogs with canine distemper, and when compared with tissue on cryostat sections, the paraffin-embedded tissue showed superior preservation of tissue architecture. The preservation of viral antigen was good, and the appearance of fluorescence in gray- and white-matter lesions was described. In gray matter, extensive fluorescence was found mainly in neurons; fluorescence in white matter was less extensive and was mainly associated with astrocytes. 相似文献
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745.
Organic beef production from steers demands several decisions concerning grazing strategy, feeding level in the winter and aspects as slaughter weight and length of the finishing period. A model has been developed to optimise these strategies. The objective of this study was (1) to find optimal strategies for organic beef production from steers regarding grazing strategy, feeding level in winter, finishing and slaughter in organic beef production from steer concerning economic output per time unit using a multi-level hierarchic Markov process and (2) to analyse the stability of these results by sensitivity analysis. The results showed that in general the optimal strategy only changes slightly depending on the criterion (net returns per steer versus per time unit). An optimization per time unit in some cases favours a more intensive production based on high feeding level in winter and finishing of steers as well as earlier slaughtering compared to an optimization per steer. Finishing of steers seemed not to be an optimal strategy from an economic point of view and price changes in feed, beef and premiums did not favour finishing of steers. Beef prices as well as prices for ryegrass/white clover pasture and low feeding level seemed to be the most important factors that influence net return. 相似文献
746.
In this review, starch behavior is described from molecules in solution to the use of starch in products. The determination of molecular characteristics with asymmetrical flow field‐flow fractionation is described, and the behavior of starch in binary solutions is discussed. The organization of starch in granules and the changes in organization during gelatinization and retrogradation are then described. The role of starch retrogradation in bread staling is described in some detail, and the influence of water mobility and distribution is discussed in relation to amylopectin retrogradation. Finally, the use of starch as emulsifier is described. Hydrophobically modified starch is one possibility for emulsion stabilization; also, the starch granule as such can be used to stabilize emulsions (so‐called Pickering emulsions). 相似文献
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748.
Sheikh Ali Ahmed Margot Sehlstedt-Persson Lars Hansson Tom Morén 《Journal of Wood Science》2013,59(1):57-66
The aim of this experiment was to impregnate thermally modified wood using an easy and cost-effective method. Industrially processed thermally modified European aspen (Populus tremula L.) and birch (Betula pubescens Ehrh.) were collected and secondarily treated at the laboratory scale with the preservatives tung oil, pine tar and Elit Träskydd (Beckers) using a simple and effective method. Preservative uptake and distribution in sample boards were evaluated using computed tomography (CT) and scanning electron microscopy (SEM) techniques. Preservative uptake and treatability in terms of void volume filled were found the highest in Beckers and the lowest in tung oil-treated samples. Thermally modified samples had lower treatability than their counterpart control samples. More structural changes after thermal modification, especially in birch, significantly reduced the preservative uptake and distribution. The differences of preservatives uptake near the end grain were high and then decreased near the mid position of the samples length as compared with similar type of wood sample. Non-destructive evaluation by CT scanning provided a very useful method to locate the preservative gradients throughout the sample length. SEM analysis enabled the visualization of the preservative deposits in wood cells at the microstructural level. 相似文献
749.
750.
LarsAsplin 《海洋水产研究》2001,22(4):29-32
A three-dimensional numerical coastal ocean model as a 2 km rectangular horizontal grid was implemented for Laizhou Bay. As a demonstration, a simulation of tidal driven flow was performed. The model can furthermore be forced by winds, river runoff and/or inflow through open boundaries. Numerical model results from simulations with realistic forcing can provide an invaluable fundament for studies on the carrying capacity of Laizhou Bay. 相似文献