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Background  

Antioxidant nutrient intake and the lesser formation of free radicals seem to contribute to chronic diseases. The aim of the present study was to evaluate the intake profile of the main dietary antioxidants in a representative sample of the adult Brazilian population and discuss the main consequences of a low intake of these micronutrients on overall health.  相似文献   
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The effects of air inlet configuration on pool fire behavior in a mechanically ventilated cabin were investigated. The closed cabin used was a model of a certain machinery cabin on a naval ship. Two air inlet configurations of one vent and two vents were taken into account together with five different elevations of air inlet. In one-vent cases, mass loss rate and gas temperature were lower and oxygen concentrations were higher than those of two-vent cases. With the increase of air inlet elevation, a sudden drop in average mass loss rate and peak temperature were found in the two-vent cases at the air inlet elevation of 1.56 m. In one-vent cases, a similar drop in average mass loss rate was found at the air inlet elevation of 0.88 m, while the peak temperature was almost unaffected by inlet elevation. According to temperature profiles and the characteristic parameter of the smoke layer stability, the formation of the smoke layer was destroyed by increasing the air inlet elevation or reducing the air inlets, and furthermore a more uniform distribution could be found. For the current cabin, the one-vent case with a lower air inlet elevation was recommended for smoke control, and the inlet should be set away from the essential equipment and the entrances of the cabin.  相似文献   
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采用平板涂布法从酱香型白酒酿造环境(大曲、酒醅和窖泥)筛选产淀粉酶细菌菌株,通过菌落形态、细胞显微结构、生理生化特性和分子生物学方法对其进行鉴定,并对其生长特性及耐受性进行研究。结果表明,从酱香型白酒大曲中筛选得到一株产淀粉酶的细菌,编号为2-2,经鉴定菌株2-2为解淀粉芽孢杆菌(Bacillus amyloliquefaciens)。菌株2-2能够在25~45 ℃和pH 5~9范围内生长良好,属于乙醇高耐受性菌株,在乙醇体积分数为12%时仍能生长,并具有较高的NaCl和葡萄糖耐受性,最高耐受质量分数分别为15%和70%。菌株2-2在高粱酶解液中能产生酱香型白酒中的多种重要风味物质,如苯乙醇、糠醇3-羟基-2-丁酮、2,5-二甲基吡嗪和乙烯基愈创木酚等,是酱香型白酒酿造中重要的功能菌株。  相似文献   
5.
We describe the apparatus used in experiment UA4 to study proton-antiproton elastic and inelastic interactions at the CERN SPS Collider. Elastically scattered particles, travelling at very small angles, are observed by detectors placed inside movable sections (“Roman pots”) of the SPS vacuum chamber. The deflection in the field of the machine quadrupoles allow the measurement of the particle momentum. Inelastic interactions are observed by a left-right symmetric system of trigger counter hodoscopes and drift-chamber telescopes. The apparatus reconstructs the interaction vertex and measures the pseudorapidity η of charged particles in the range 2.5 < 6η6 < 5.6.  相似文献   
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Activation of K-ras gene by point mutations, a common finding in lung adenocarcinomas, has been suggested to decrease patient survival. We investigated 109 lung adenocarcinomas, mostly small, peripheral, stage I tumours (81/109) for presence of K-ras gene mutations at codons 12 and 13. Mutations were detected by denaturing gradient gel electrophoresis analysis of specific sequences amplified by polymerase chain reaction from DNA extracted from archival pathological material. Thirty-three of 109 (30.3%) tumours showed mutations at codon 12 (28/33, 84.8%) or 13 (5/33, 15.2%) of the gene. Mutations and type of nucleotide substitutions were differently distributed among cytological subtypes, being more prevalent among less differentiated (G2 and G3) tumours and among bronchial than bronchiolo-alveolar type adenocarcinomas. Survival analysis showed an adverse effect of K-ras mutation on survival, restricted to stage I tumours. Median survival for 81 stage I patients was 30 months for non-mutated tumours versus 20 months for mutated tumours (p = 0.016). Multivariate analysis showed that age of patient (p = 0.001) and K-ras mutation status (p = 0.04) were the only independent factors influencing survival significantly. These data strengthen the hypothesis that K-ras gene mutations may be useful in identifying a subgroup of patients with poor outcome.  相似文献   
8.
We report an application of Kalman filtering to the inverted pendulum (IP) of the Virgo gravitational wave interferometer. Using subspace method system identification techniques, we calculated a linear mechanical model of Virgo IP from experimental transfer functions. We then developed a Kalman filter, based on the obtained state space representation, that estimates from open loop time domain data, the state variables of the system. This allows the observation (and eventually control) of every resonance mode of the IP mechanical structure independently.  相似文献   
9.
During embryonic development, the proper production of extracellular matrix molecules mediates morphogenetic processes involved in palatogenesis. In the present study, we investigated whether any differences exist in glycosaminoglycan (GAG) and collagen synthesis between palate fibroblasts from infants, with or without cleft palate, in two age ranges. Subsequently, the effects of diphenylhydantoin (PHT), a teratogen known to induce cleft palate in human and mammalian newborns, on extracellular matrix (ECM) production were studied. We found that cleft palate fibroblasts (CPFs) synthesize greater amounts of GAG and collagen than normal fibroblasts (NFs). CPFs produced less cellular hyaluronic acid (HA) and more sulphated GAG. HA was the principal GAG species in the medium, and its percentage was lower in one- to three-year-old CPFs. Cleft palate fibroblasts produced more extracellular chondroitin 4- and 6-sulphate (CS) and dermatan sulphate (DS). Associated with a higher production of sulphated GAG, we observed a higher synthesis of type III and type I collagen with a normal ratio of alpha2(I) to alpha1(I) chains. PHT treatment of NFs reduced collagen and GAG synthesis, with a marked effect on sulphated GAG. The drug changed collagen synthesis, whereas it did not affect GAG production in CPFs whose phenotype may already be impaired. These findings indicate that, in CPFs, modifications in the pattern of ECM components, which are most likely responsible for the anomalous development, persist in infants. In addition, NFs and CPFs with a different phenotype respond differently to PHT treatment.  相似文献   
10.
Thirty two weaned pigs (24 d-old) were fed a diet without or with 1% (w/w) thymol. Pigs from each dietary treatment remained unchallenged or were challenged with Salmonella enterica serovar typhimurium. Jejunal content was collected and molecular microbial diversity was investigated using 16S rRNA gene polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Shannon index analysis showed no differences in diversity but Pearson coefficient analysis showed clear clustering of profiles, which delineated thymol fed and control groups irrespective of Salmonella challenge. Moreover, absence of bands corresponding to Actinobacillus minor (98-99% identity) was observed in thymol groups. A band corresponding to Citrobacter freundii (98% identity) was observed in almost all pigs from thymol groups, and only in 4 samples from pigs fed no thymol in the diet. Supplementation of pig diet with thymol caused clear changes in small intestine microbacterial community. Surprisingly, Salmonella infection caused no major perturbations to the community structure.  相似文献   
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