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141.
142.
Intestinal wall thickness is neither a specific nor sensitive ultrasound parameter for detecting intestinal inflammation. We hypothesize that mucosal echogenicity, lymphadenomegaly, and secondary findings of the gastrointestinal tract would be more sensitive and specific markers for detecting and differentiating causes of chronic inflammatory bowel disease in dogs. Fifty-six client-owned dogs with chronic diarrhea and 10 control dogs were examined with two-dimensional, gray-scale ultrasound (time 0, 4, and 10 weeks post therapy) and small intestinal mucosal biopsies were performed at the 0- and 4-week time points. The clinical activity was assessed at each time point using the canine inflammatory bowel disease activity index (CIBDAI). Fifty-one dogs had inflammatory infiltration of the duodenal mucosa and were divided into three groups, food-responsive disease, idiopathic inflammatory bowel disease, and protein-losing enteropathy, based on their response to the different treatments and histology. Two different patterns of increased echogenicity of the mucosa were detected: hyperechoic speckles and hyperechoic striations. A normal, hypoechoic bowel mucosa in dogs with chronic diarrhea had a sensitivity of 80% and a specificity of 81% for the diagnosis of food-responsive disease. Hyperechoic striations had a sensitivity of 75% and a specificity of 96% for dogs with protein-losing enteropathy. Hyperechoic speckles were non-specific for diagnosing inflammatory bowel disease. There was a significant relationship between ultrasound score and CIBDAI at t0, but not following therapy. Mucosal echogenicity may be a better parameter for detecting inflammatory bowel disease than bowel wall thickness in dogs with chronic diarrhea.  相似文献   
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144.
The influence of two iron sources, FeCl3 and iron ethylenediaminetetraacetic acid (FeEDTA), and an iron chelator, ethylenediamine di-o-hydroxyphenylacetic acid, on wheat straw decomposition was monitored in laboratory incubations. Adding FeCl3 or FeEDTA to the incubation buffer did not alter the rate of decomposition, but the addition of the iron chelator, EDDHA, slowed decomposition significantly. These data suggest that microorganisms that produce iron chelators might be used to reduce residue decomposition in the field.  相似文献   
145.
Summary When lines of constant moisture content (isosteres) are plotted on axes of In r (r, relative humidity) versus In ps (ps, pressure of water vapour at saturation), approximately straight lines result. Other axes with the same property are discussed. The slope of lines of constant Gibbs free energy of water vapour is derived for the above chart and it is shown that the basic equation of sorption is represented by this slope and that of the isostere.  相似文献   
146.
 Creep and sorptive-mechano-effect are defined in terms of complementary partial derivatives. The nett strain and the distribution of mechanical strain in a board of rectangular cross-section is predicted where the board is dried by the progression of a square front. The effects of creep and sorptive-mechano-effect are considered separately and when both are effective. Received 20 September 1999  相似文献   
147.
 The phenomenon of collapse and consequent checking of certain species of timber during drying is thought to result from mechanical stresses which in turn are caused by tension in capillary-held lumen water. The cell-structure is modelled as a two-dimensional grid of cells. For a given value of the capillary tension and for a given cell wall geometry the distribution of mechanical stresses is prescribed and can be determined using the equilibrium equations of solid mechanics. An approximate solution to these equations is investigated and it is considered to give useful information with regard to potential modes of failure and the influence of otherwise imposed stresses. Received 28 September 1998  相似文献   
148.
Summary An investigation into the bonding energy relationships for water in wood indicates that as the temperature increases at constant total moisture content, water moves from within the chemical structure to the adsorption surface. The analysis is evaluated for the wood Araucaria klinkii Lauterb and it is indicated that at 25 °C, less water is held in the chemical structure during adsorption than during desorption.Symbols A amplitude of liquid surface profile - A0 amplitude of solid surface profile - a mean radius of curvature of liquid surface (bubble radius), Å - a0 mean radius of curvature of solid surface, Å - ac a constant value of a, Å - F a function of temperature - f capisorption energy fraction - G a function of - g specific Gibbs free energy of saturated water vapour relative to unsaturated water vapour at the same temperature, J/kg - gc specific Gibbs free energy associated with capisorption, J/kg - gp specific Gibbs free energy associated with physisorption, J/kg - h change in specific enthalpy of liquid water as it is desorbed, J/kg - l latent heat of vaporisation of free water, J/kg - m wave number/m - ps pressure of water vapour at saturation, Pa - R specific gas constant for water vapour, J/kg K - r relative humidity - s change in specific entropy of liquid water as it is desorbed, J/kg K - T temperature, K - w dry basis moisture content - x ln ps/ps25 - y In r - z length coordinate, m - , , constant coefficients - change in mean height of liquid surface, Å - 0 a constant length, Å - constant - distance from solid to liquid vapour interface measured normal to solid surface, Å - 0 a constant value of , Å  相似文献   
149.
Six Salix clones and four Melampsora larici‐epitea isolates were used in two leaf‐disc inoculation experiments to determine whether disease severity was affected by the presence of both virulent and avirulent rust genotypes. In the first experiment, an equal amount of urediniospores of a virulent isolate and an avirulent isolate was applied simultaneously using four levels of spore suspension. In the second, the willows were inoculated with one isolate first and then, after 3 days, with another using two spore concentrations. In the first experiment, overall rust spore production was reduced by 48.6% in inoculations with mixed inocula compared with that in the inoculations with single virulent isolates. In the second experiment, 20 of the 36 combinations involving pre‐inoculations with avirulent isolates showed significant reduction in spore production. The suppressive effects on rust sporulation were more obvious at the higher inoculum densities and on the clones S. × calodendron and S. × mollissima‘Q83’.  相似文献   
150.
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