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The objective of this study was to develop a model to simulate salt release during eating. Salt release kinetics during eating was measured for four model dairy products with different dynamic salty perceptions. A simple in vivo model of salt release was developed to differentiate between the contribution of the individual and of the product to salt release. The most difficult model parameter to determine or predict is the evolution of the contact area between the product and the saliva. Fitting the model to the experimental data showed that the subject's masticatory performance and fracture initiation energy of the product determined the contact area between the product and the saliva generated by mastication. Finally, the role of release dynamics on sensory time-intensity profiles is discussed.  相似文献   
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The present study aimed at evaluating the effects of different doses of silymarin in diet on broiler performances and meat quality. For the trial, 180 male chicks (ROSS 508), were allocated in to three groups (S0, S40 and S80) of 60 animals each receiving a basal diet supplemented with 0 ppm, 40 ppm and 80 ppm of a sylimarin (provided by a dry extract of Silybum marianum fruits) respectively. During the trial feed consumption and live body weight were taken every 20 days. At the age of 40 and 60 days blood samples were taken in order to evaluate protein, aspartate aminotransferase, cholesterol, tryglicerides and uric acid. At the age of 60 days animals were slaughtered, dressing percentages were evaluated and samples of breast and meat were taken to evaluate chemical composition and susceptibility of lipid peroxidation by means of thiobarbituric acid reactive substances. Silymarin at the tested doses did not affect growth performances but slightly affected slaughtering yields negatively, no specific hepatoprotective effect was found. Treatments reduced lipid content of both breast and thigh and increased muscles resistance to oxidative stress.  相似文献   
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The reliability of repeated measurements of vertical ground reaction force (GRF) variables was determined using 10 clinically sound adult dogs walking on a treadmill three times daily on three different days. Peak vertical force, vertical impulse and duration of stance phase of each limb were determined and analysed for significant differences within and between days and between dogs. Contributions to the variance of GRF were determined using a random effect model including dogs, different days, trials and extremities. ANOVA did not show any significant differences in variables within and between days, but did reveal differences between dogs. Variance was mainly seen in different dogs, whereas different days and trials were less important factors. It was concluded that the ground reaction forces determined by a treadmill system are suitable and provide reproducible parameters in canine gait analysis. Such treadmill/force plate systems allow the simultaneous measurement of all four legs of dogs at a constant velocity walk.  相似文献   
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Cytauxzoon felis typically causes fatal disease in domestic cats. Survival after infection and persistent parasitemia without clinical illness has been documented in a few cases. To our knowledge there are no prevalence studies of C. felis in domestic cats. The purpose of this study was to estimate the prevalence of C. felis infected cats that were presented to trap-neuter-return programs in Florida, North Carolina and Tennessee. Cats that were presented to trap-neuter-return programs were tested using a C. felis-specific PCR assay. A total of 961 domestic cats were tested (494 from Florida; 392 from North Carolina; 75 from Tennessee). Prevalence of C. felis infection in this population was 0.3%. Two cats from Florida and one cat from Tennessee tested positive for the presence of C. felis DNA. These amplicons were sequenced and confirmed to be C. felis. The cat from Tennessee was alive without evidence of illness 2 months post-surgery. The other two cats were alive 24 h post-surgery, but were then lost to follow-up. This is the first report documenting C. felis infections in free-roaming cats. Despite the low prevalence rate, the presence of apparently healthy infected free-roaming cats suggests that they may have the capacity to serve as an additional reservoir host for C. felis. Further investigations should evaluate the potential vector competence of domestic cats as well as the role of chronically infected cats in areas in which cytauxzoonosis appears hyperendemic.  相似文献   
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The murine norovirus (MNV) is a recently discovered mouse pathogen, representing the most common contaminant in laboratory mouse colonies. Nevertheless, the effects of MNV infection on biomedical research are still unclear. We tested the hypothesis that MNV infection could alter immune response in mice with acute lung infection. Here we report that co-infection with MNV increases survival of mice with Pseudomonas aeruginosa acute lung injury and decreases in vivo production of pro-inflammatory cytokines. Our results suggest that MNV infection can deeply modify the parameters studied in conventional models of infection and lead to false conclusions in experimental models.  相似文献   
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This study was conducted to determine if the main components of the somatotropic axis change during the early phase of pregnancy in the maternal blood system and whether differences exist on day 18 after pregnancy recognition by the maternal organism. Blood samples of pregnant heifers (Holstein Friesian; n = 10 after embryo transfer) were obtained on the day of ovulation (day 0), as well as on days 7, 14, 16 and 18 and during pregnant, non-pregnant and negative control cycles. The oncentrations of progesterone (P4), oestrogen, growth hormone (GH), insulin-like growth factor-1 and -2 (IGF1, -2) and IGF-binding protein-2, -3 and -4 (IGFBP2, -3, -4) were measured. The mRNA expressions of growth hormone receptor 1A, IGF1, IGF2, IGFBP2, IGFBP3 and IGFBP4 were detected using RT-qPCR in liver biopsy specimens (day 18). In all groups, total serum IGF1 decreased from day 0 to 16. Notably, IGFBP4 maternal blood concentrations were lower during pregnancy than during non-pregnant cycles and synchronized control cycles. It can be speculated that the lower IGFBP4 in maternal blood may result in an increase of free IGF1 for local action. Further studies regarding IGFBP4 concentration and healthy early pregnancy are warranted.  相似文献   
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