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111.
Biological Variability in Serum Cortisol Concentration Post‐adrenocorticotropic Hormone Stimulation in Healthy Dogs
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Bouhlel C Dolhem G Fernandez X Antoniotti S 《Journal of agricultural and food chemistry》2012,60(4):1052-1058
A protocol based on the use of horseradish peroxidase (HRP) is proposed for the removal of allergenic eugenol from rose essential oil without loss of the organoleptic quality and with a good conservation of the chemical composition. For the first time, an enzyme-based strategy is proposed for essential oils treatment and opens new opportunities in the detoxification of natural extracts used in perfumery and cosmetics. Our results on eugenol in rose essential oil constitute a first step toward the development of efficient and mild processes for the removal of more toxic compounds of natural extracts. 相似文献
114.
Farrah R. Fatemi Ivan J. Fernandez Johanna Szillery Stephen A. Norton Lindsey E. Rustad 《Water, air, and soil pollution》2012,223(9):6171-6186
We examined long-term changes in soil solution chemistry associated with experimental, whole watershed-acidification at the Bear Brook Watershed in Maine (BBWM). At BBWM, the West Bear (WB) watershed has been treated with bimonthly additions of ((NH4)2 SO4) since 1989. The adjacent East Bear (EB) watershed serves as a biogeochemical reference. Soil solution chemistry in the EB watershed was relatively stable from 1989?C2007, with the exception of declining SO4?CS concentrations associated with a progressive decline in SO4?CS deposition during this period. Soil solution chemistry in WB reflected a progressive change in acid-neutralization mechanisms from base cation buffering to Al buffering associated with treatment during this period. Total dissolved Al concentrations progressively increased over time and were ~4× higher in 2007 than in 1989. Treatment of WB was also associated with long-term increases in soil solution H+, SO4?CS, and NO3?CN, whereas soil solution dissolved organic carbon (DOC) was unresponsive to treatment. For solutes such as Ca, H+, and SO4?CS, changes in stream chemistry were generally parallel to changes in soil solution chemistry, indicating a close coupling of terrestrial and aquatic processes that regulate the chemistry of solutions in this first-order stream watershed. For other solutes such as Al and DOC, solute concentrations were higher in soil solutions compared with streams, suggesting that sorption and transformation processes along hydrologic flow-paths were important in regulating the chemistry of solutions and the transport of these solutes. 相似文献
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CA Letelier MA Sanchez RA Garcia‐Fernandez B Sanchez P Garcia‐Palencia A Gonzalez‐Bulnes JM Flores 《Reproduction in domestic animals》2011,46(3):481-488
The aim of the current study was to determine the possible effects of progestagen oestrous synchronization on vascular endothelial growth factor (VEGF) expression during sheep luteogenesis and the peri‐implantation period and the relationship with luteal function. At days 9, 11, 13, 15, 17 and 21 of pregnancy, the ovaries from 30 progestagen treated and 30 ewes cycling after cloprostenol injection were evaluated by ultrasonography and, thereafter, collected and processed for immunohistochemical evaluation of VEGF; blood samples were drawn for evaluating plasma progesterone. The progestagen‐treated group showed smaller corpora lutea than cloprostenol‐treated and lower progesterone secretion. The expression of VEGF in the luteal cells increased with time in the cloprostenol group, but not in the progestagen‐treated group, which even showed a decrease between days 11 and 13. In progestagen‐treated sheep, VEGF expression in granulosa‐derived parenchymal lobule capillaries was correlated with the size of the luteal tissue, larger corpora lutea had higher expression, and tended to have a higher progesterone secretion. In conclusion, the current study indicates the existence of deleterious effects from exogenous progestagen treatments on progesterone secretion from induced corpora lutea, which correlate with alterations in the expression of VEGF in the luteal tissue and, this, presumably in the processes of neoangiogenesis and luteogenesis. 相似文献
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Marie-Etancelin C Basso B Davail S Gontier K Fernandez X Vitezica ZG Bastianelli D Baéza E Bernadet MD Guy G Brun JM Legarra A 《Journal of animal science》2011,89(3):669-679
Genetic parameters of traits related to hepatic lipid metabolism, carcass composition, and product quality of overfed mule ducks were estimated on both parental lines of this hybrid: the common duck line for the maternal side and the Muscovy line for the paternal side. The originality of the statistical model was to include simultaneously the additive genetic effect of the common ducks and that of the Muscovy ducks, revealing a greater genetic determinism in common than in Muscovy. Plasma metabolic indicators (glucose, triglyceride, and cholesterol contents) were heritable, in particular at the end of the overfeeding period, and heritabilities increased with the overfeeding stage. Carcass composition traits were highly heritable in the common line, with values ranging from 0.15 for liver weight, 0.21 for carcass weight, and 0.25 for abdominal fat weight to 0.32 for breast muscle weight. Heritabilities of technological outputs were greater for the fatty liver (0.19 and 0.08, respectively, on common and Muscovy sides for liver melting rate) than for the pectoralis major muscle (between 0.02 and 0.05 on both parental sides for cooking losses). Fortunately, the processing industry is mainly facing problems in liver quality, such as too high of a melting rate, than in meat quality. The meat quality appraisal criteria (such as texture and cooking losses), usually dependent on pH and the rate of decline of pH, were also very lowly heritable. This study demonstrated that genetic determinism of meat quality and ability of overfeeding is not similar in the common population and in the Muscovy population; traits related to fattening, muscle development, and BW have heritability values from 2 to 4 times greater on the common line than on the Muscovy line, which is relevant for considering different selection strategies. 相似文献
119.
1. Within a large flock of turkey toms (2000 BUT9 conventionally reared and slaughtered), early muscle pH measurements were randomly done to distinguish two groups of birds presenting low (fast glycolysing, GR) or normal (normal glycolysing, GN) values. 2. Subsequently, ultimate pH values and meat quality parameters were also recorded. Meat quality parameters from GR or GN samples differ more or less indicating more or less severe PSE conditions. Proteins extracted from the samples at 20 min post mortem were similar while they differed greatly at 24 h post mortem. Moreover, among the GR birds, a subgroup of animals (called AB) presented SDS-PAGE profiles largely different from other GR or GN birds. 3. All the subsequent analysis developed on meat quality parameters as well as for protein extractabilities also differed between AB and other animals indicating that they must be considered differently in term of PSE syndrome development. 4. Western blots against Myosin Heavy Chain and actin at 24 h post mortem indicate that myofibrillar protein alterations are different in AB and GR or GN samples. 5. At 20 min post mortem, glycogen content was lowest in AB samples while the glycolytic potential was similar in all samples at the time of death. Measurements of PFK enzyme specific activity did not indicate a different regulation of post mortem glycolysis in AB samples. 6. Our results suggest that a unique pH measurement at 20 min post is insufficient to detect animals more prone to developing a severe PSE syndrome in turkeys. In consequence, it is suggested that a more precise evaluation of the kinetics of pH and temperature decrease has to be conducted to understand the aetiology of meat quality parameter alterations in poultry. 相似文献
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