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The PPARGC1A gene (peroxysome proliferator-activated receptor-γ coactivator 1α gene) controls muscle fiber type and brown adipocyte differentiation; therefore, it is a candidate gene for beef quality traits (tenderness and fat content). Two SNPs (Single Nucleotide Polymorphisms) were identified within exon 8 by multiple alignment of DNA sequences obtained from 24 bulls: a transition G/A (SNP 1181) and a transversion A/T (SNP 1299). The SNP 1181 is a novel SNP, corresponding to a non-conservative substitution (AGT/AAT) that could be the cause of amino acid substitution (364Serine/364Asparagine). A Mismatch PCR method was designed to determine genotypes of 73 bulls and 268 steers for SNP 1181. Growth, slaughter and meat quality information were available for the group of steers. Allele A of SNP 1181 was not found in Angus. In 243 steers, no significant differences (P > 0.05) were found for either final live body weight, gain in backfat thickness in Spring, kidney fat weight, kidney fat percentage, Warner–Bratzler shear force at 7 days postmortem, intramuscular fat percentage or meat colour between genotype GG and AG. This SNP could be included in breed composition and population admixture analyses because there are marked differences in allelic frequencies between Bos taurus and Bos indicus breeds.  相似文献   
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A student, future decision-maker, has to measure the consequences of his indecision. In this study, a model of work with doubt is tested. We observe that the indecision is correlate with knowledge. His taking into consideration from continuous assessments allows us to predict his academic standard.  相似文献   
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The acute effects of opiate drugs and opiate addiction have been associated with modulation of Fas/FADD (Fas-Associated protein with Death Domain) signaling complex in the rat brain. This study investigated the possible existence of endogenous opioid tones regulating the basal activities of Fas receptor forms and FADD in the brain, using gene-targeted mice lacking mu-, delta- or kappa-opioid peptide receptors (KO mice). In mu-KO mice, but not in delta- or kappa-KO mice, the basal immunodensity of native Fas (35 kDa monomeric form) was decreased in the cerebral cortex (33%) when compared with WT littermates. In delta-KO mice, but not in mu- or kappa-KO mice, the basal content of 120 kDa Fas aggregates (complexes of monomers relevant in Fas signaling) was markedly increased in the cortex (93%). In contrast, no differences between genotypes were observed in the basal expression of glycosylated Fas (51/48/45 kDa forms). Notably, the basal content of FADD (the adaptor protein that couples Fas to caspases and transmits the death signal) was increased in the cerebral cortex of delta-KO mice (48%), but not in mu- or kappa-KO mice. In addition, the basal content of phosphorylated FADD at Ser191 (the relevant species of FADD implicated in nonapoptotic signals) was also upregulated in the cortices of delta-opioid receptor KO mice (6.5-11.0-fold). The results suggest that mu-receptors tonically stimulate (through endogenous opioid peptides) the activation of native Fas, whereas delta-receptors tonically inhibit the expression of Fas aggregates and that of FADD and phosphorylated FADD (Ser191) in the mouse brain. These data are in line with the acute opposite modulation of Fas and FADD induced by mu- and delta-opiate agonists, and strongly support the notion of an anti-apoptotic delta-opioid tone that restrains Fas signaling.  相似文献   
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To assess the efficacy of noninvasive ventilation (NIV) in patients with persistent weaning failure, we conducted a prospective, randomized, controlled trial in 43 mechanically ventilated patients who had failed a weaning trial for 3 consecutive days. This trial was stopped after a planned interim analysis. Patients were randomly extubated, receiving NIV (n = 21), or remained intubated following a conventional-weaning approach consisting of daily weaning attempts (n = 22). Compared with the conventional-weaning group, the noninvasive-ventilation group had shorter periods of invasive ventilation (through tracheal intubation) (9.5 +/- 8.3 vs. 20.1 +/- 13.1 days, p = 0.003) and intensive care unit (ICU) (14.1 +/- 9.2 vs. 25.0 +/- 12.5 days, p = 0.002) and hospital stays (27.8 +/- 14.6 vs. 40.8 +/- 21.4 days, p = 0.026), less need for tracheotomy to withdraw ventilation (1, 5% vs. 13, 59%, p < 0.001), lower incidence of nosocomial pneumonia (5, 24% vs. 13, 59%, p = 0.042) and septic shock (2, 10% vs. 9, 41%, p = 0.045), and increased ICU (19, 90% vs. 13, 59%, p = 0.045) and 90-day survival (p = 0.044). The conventional-weaning approach was an independent risk factor of decreased ICU (odds ratio: 6.6; p = 0.035) and 90-day survival (odds ratio: 3.5; p = 0.018). Earlier extubation with NIV results in shorter mechanical ventilation and length of stay, less need for tracheotomy, lower incidence of complications, and improved survival in these patients.  相似文献   
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