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51.
The effects of blending rice flour with wheat flour on bread texture and staling were investigated with three rice varieties with different amylose contents. For the texture analysis of bread crumb, the compression test, puncture test, and tensile test were performed. A flour blend containing rice flour suppressed the recovery of the crumb after compression. For the puncture test, blends with rice flour increased the distance to penetrate the crumb. The rupture strain measured with the puncture test decreased with staling of the bread crumb for all samples tested. The fresh bread crumb sample containing waxy rice flour had much greater extensibility in the tensile test than the other samples tested, but it was dramatically decreased after one day of storage. Endothermic enthalpies corresponding to retrograded amylopectin, which is part of the staling process, were also measured. The enthalpy of bread crumb from the blended flour was lower than that of wheat flour bread up to three days but was higher on day 4. A blend of rice flour thus reduced amylopectin retrogradation during early storage, but it was accelerated later. Bread blended with waxy rice flour showed the lowest enthalpy during storage.  相似文献   
52.
The effect of 0, 1, 2, 3 and 4 intercross cycles using genetic male sterility on the mean yield and genetic variability of the CNA 5 irrigated rice synthetic population was assessed studying 300 S0:2 (1998/99) and S0:3 (1999/00) families grown in two locations (Lambari, MG and Goianira, GO). Each intercross was investigated using a 8 × 8 triple lattice design experiment containing 60 families and four control cultivars. Five experiments were carried out per location and generation, totaling 20 experiments. Individual, combined over locations, combined over generations and combined over locations and generations analyses of variance were performed. Linear regression equations were fitted to data of each location and generation as well as, genetic and phenotypic parameters were estimated. An average increase of 3.91% in grain yield was obtained with the increase in the number of intercrosses. However, when genetic gains obtained from selection of the five and ten highest yielding families were considered, negative b estimates were always obtained, suggesting a tendency of gain increase reduction with the increase in the number of intercrosses. This was confirmed by the analysis of the means of the best families, since increases in the number of intercrosses did not result in selection of families with greater mean grain yield. The estimates of the genetic variances and heritabilities did not suggest an increase in genetic variability with the increase in intercross cycles. Therefore, carrying out intercrosses on the base population did not improve the results of the irrigated rice recurrent selection program. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
53.
The objective of this study was to describe a standardised and non-invasive method for exhaled breath condensate (EBC) collection in cats and to test whether determination of hydrogen peroxide (H(2)O(2)) in EBC might be used as marker of lower airway inflammation. The technique of barometric whole body plethysmography for cats was combined with a system to condense the effluent air from the plethysmograph, allowing simultaneous EBC collection and respiratory pattern measurement. H(2)O(2) was determined spectrophotometrically. Eighteen experimental cats were used to investigate the impact on EBC volume and EBC H(2)O(2) of plethysmograph ventilation rate, collection duration, sample stability, within-day and day-to-day variability. After determination of a standardised EBC collection procedure, correlation analyses between EBC H(2)O(2) and bronchoalveolar lavage (BAL) cytology of healthy and allergen-challenged Ascaris suum (AS)-sensitised cats were performed. A significant and positive correlation between EBC H(2)O(2) and bronchoalveolar lavage (BAL) neutrophil% was found in healthy cats (P < 0.001, r = 0.55), whereas in AS-sensitised cats, correlation with BAL eosinophil% was significant (P < 0.005, r = 0.61). H(2)O(2) was increased after an allergen challenge in AS-sensitised cats (n = 6, 0.56+/-0.12 versus 1.08+/-0.35 micromol/L, P < 0.05). This study proposes a non-invasive, well tolerated and repeatable method of EBC collection for cats and suggests that EBC H(2)O(2) might be used as non-invasive biomarker for monitoring lower airway inflammation.  相似文献   
54.
The prevalence of anti-Toxoplasma gondii antibodies was evaluated by the indirect immunofluorescent-antibody test in serum of 57 wild canids from three different species: Lycalopex gymnocercus, Cerdocyon thous and Dusicyon vetulus from the northeast, southeast and southern regions of Brazil. The prevalence was 35.1%, with 20 of the 57 canids demonstrating antibodies anti-T. gondii at dilutions of 1:16 in 2, 1:32 in 4, 1:64 in 2, 1:128 in 2, 1:256 in 6, 1:512 in 2 and 1:2048 in 2 animals. None of the D. vetulus were positive. Among the L. gymnocercus 11 (91.7%) of the 12 samples were positive and among C. thous 9 (60%) of the 15 had antibodies anti-T. gondii.  相似文献   
55.
REASONS FOR PERFORMING STUDY: Feeding practices have been associated with colic in horses. If meal size and composition have an effect on gastric emptying, this could be one of the mechanisms by which feeding practices are related to the occurrence of colic. OBJECTIVES: To evaluate the effect of meal size and starch content on solid phase gastric emptying. METHODS: Solid phase gastric emptying of 3 different radiolabelled meals, small low-starch (SmLS), small high-starch (SmHS) and large high-starch (LgHS) meals, was measured in 5 horses by scintigraphy using 99mTc-disofenin. Data were compared among meals using nonlinear mixed-effects models and paired t tests. RESULTS: On a percentage basis, SmHS emptied significantly faster than LgHS and SmLS emptied significantly faster than SmHS meals. However, when meals of unequal size were compared by emptying rate in g/min and Kcal/min, LgHS emptied significantly faster than SmHS. CONCLUSIONS: Meal size and composition affect gastric emptying. POTENTIAL RELEVANCE: Further work needs to be performed in order to substantiate the possibility of a relationship between digestive functions and occurrence of colic and gastric ulcers.  相似文献   
56.
57.
The molecular profile of 30 Moraxella bovis strains, recovered from outbreaks of infectious bovine keratoconjunctivitis in Argentina, Brazil and Uruguay between 1974 and 2001, was determined through randomly applied polymorphic DNA (RAPD) analysis. Molecular profiles of nine strains recovered after 1990 varied from those recovered before 1990. The profiles of 13 strains (48%) differed from those of three vaccinal strains extensively used since 1984 in Argentina and Uruguay. Eight Argentinean strains, one from Brazil and two from Uruguay had identical RAPD profiles. Strains belonging to different serogroups had identical RAPD profiles, demonstrating that this technique was not able to discriminate among strains with low cross-reactivity indices. RAPD may be helpful in the primary characterization of M. bovis strains, but it does not replace serological characterization.  相似文献   
58.
A structure-function study was carried out to increase knowledge of how glycosidic linkages and molecular weights of carbohydrates contribute toward the selectivity of fermentation by gut bacteria. Oligosaccharides with maltose as the common carbohydrate source were used. Potentially prebiotic alternansucrase and dextransucrase maltose acceptor products were synthesized and separated into different molecular weights using a Bio-gel P2 column. These fractions were characterized by matrix-assisted laser desorption/ionization time-of-flight. Nonprebiotic maltooligosaccharides with degrees of polymerization (DP) from three to seven were commercially obtained for comparison. Growth selectivity of fecal bacteria on these oligosaccharides was studied using an anaerobic in vitro fermentation method. In general, carbohydrates of DP3 showed the highest selectivity towards bifidobacteria; however, oligosaccharides with a higher molecular weight (DP6-DP7) also resulted in a selective fermentation. Oligosaccharides with DPs above seven did not promote the growth of "beneficial" bacteria. The knowledge of how specific structures modify the gut microflora could help to find new prebiotic oligosaccharides.  相似文献   
59.
60.
The objective of this study was to establish a reference base for respiratory variables (respiratory rate [R(R)], inspiratory and expiratory time [T(i) and T(e)], peak inspiratory and expiratory pseudoflow [PIF and PEF], tidal volume [V(T)], minute ventilation [V(E)] and enhanced pause [Penh]) of healthy cats by use of barometric whole body plethysmography (BWBP). Eighteen healthy European cats (10 male, 8 female) were studied from the age of 3 to 13 months in order to assess growth- and gender-related changes of BWBP variables. Chest radiographs and bronchoalveolar lavage cytology were performed to confirm pulmonary health status. Diurnal changes were investigated every 2 h over a period of 24 h when the cats were adult. V(T), V(E), PIF and PEF significantly increased during somatic growth and were higher in males than in females, whereas R(R), T(i), T(e), T(e)/T(i) ratio, PEF/PIF ratio and Penh remained unchanged and were not affected by gender. When measured over 24 h, Penh, T(e) and T(i) were significantly increased in the early morning hours (04:00 h), whereas R(R), PIF and PEF were decreased at that time. This study provides reference values of BWBP variables for healthy male and female cats and indicates when circadian changes might be observed.  相似文献   
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