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There has been considerable controversy about the use of selected pure strains in wine fermentation. For that reason it is important to determine the influence of this vinification technique in the composition of wine because it arises from the type of yeast and the subsequent evolution during fermentation. This study researches the volatile composition of rosé wines from the Garnacha must, inoculated with one selected NA33 strain of Saccharomyces cerevisiae. The inoculated yeast did not predominate in all of the samples. These samples showed a behavior intermediate between those of the control and samples in which NA33 did predominate. The greatest concentration of higher alcohols was in the control wine, and its evolution was similar in all fermentations. The esters formed at the end of the fermentation and their concentrations were higher in the control than in the inoculated samples. In the control, acids were produced above all, in the first half of fermentation, and decreased from then onward. In the sample in which the yeast predominated, the synthesis occurred later and to a lesser extent than in the control.  相似文献   
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The ability to attach to the host cell surface has been considered an important virulence strategy in many bovine mammary gland pathogens, including Streptococcus uberis. Research conducted in our laboratory lead to the identification of an S. uberis adhesion molecule (SUAM) with affinity for bovine lactoferrin (LF) and delineation of its role in adherence of S. uberis to bovine mammary epithelial cells. Using a selected bacterial surface protein extraction protocol and affinity chromatography, a 112-kDa protein that had a similar molecular mass and the LF affinity as one of the identified S. uberis LBP described by Fang and Oliver in 1999 was found. To further characterize SUAM, the N-terminal amino acid sequence of this protein was elucidated. A protein query versus translated database TBLASTN search of the National Center for Biotechnology (NCBI), non-redundant database, nr, with the LBP N-terminal amino acid sequence showed no significant similarity with previous entries. Antibodies directed against SUAM and a 17 amino acid long N-terminal sequence (pep-SUAM) inhibited adherence to and internalization of S. uberis UT888 into bovine mammary epithelial cells. Data presented suggests that we have discovered a novel bacterial protein involved in the pathogenesis of this economically important mastitis pathogen.  相似文献   
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This article reports genetic analysis of the weight at different ages of Murrah water buffaloes, using random regression models (RRM). Models ranging from third to sixth order polynomial were used to describe direct genetic and animal permanent environmental effects. Contemporary group was included as a fixed effect, and a cubic polynomial was used to model the mean curve of the population. The residual was modeled considering a log‐linear function. Two models were selected for study of genetic parameters. The first model included third and sixth order polynomials for direct genetic and animal permanent environmental effects (M36). The second model included sixth order polynomials for all random effects (M66). The estimates of heritability varied from 0.16 + 0.04 (44 days) to 0.38 + 0.04 (568 days) for model M36 and from 0.16 + 0.05 (33 days) to 0.42 + 0.05 (600 days) for model M66. Regarding estimates of the correlation for all effects, the magnitude tended to decline with the increase of the time span between measurements. These results indicate that the species has potential for genetic selection based on weight at different ages, since we found favorable genetic variability within the herd, with selection likely to be more efficient at ages near 600 days.  相似文献   
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An 8‐month‐old neutered male ferret was presented for vaccination and preventive treatment for adrenal gland disease. Abdominal ultrasound revealed severe bilateral hydronephrosis and hydroureter. Excretory urography and negative contrast cystography showed bilateral ureterovesical junction stenosis. Positive retrograde cystography demonstrated right ureteral reflux. A subcutaneous ureteral bypass was placed in the left kidney; however, it had to be removed 3 months later due to an obstruction and persistent urinary tract infection. Bilateral ureteroneocystotomy was performed. Although congenital strictures are uncommon in veterinary patients, they should be included in the differential diagnosis in ferrets presenting with hydronephrosis and hydroureter of undetermined cause.  相似文献   
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