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91.
92.
Sandra?Valois Hugo?Costa-RibeiroJr ?ngela?Mattos Tereza?Cristina?Ribeiro Carlos?Maurício?Mendes Fima?LifshitzEmail author 《Nutrition journal》2005,4(1):23
In order to assess the effects of juice feedings during acute diarrhea a double-blind, randomized study was performed in 90
children, mean age of 10 ± 4.28 months. Thirty patients with acute diarrhea were fed twice-daily 15 ml/kg of Apple Juice (AJ),
30 received White Grape Juice (WGJ), and 30 were given colored and flavored water (WA) as part of their age appropriate dietary
intake. The duration and severity of diarrhea were the main endpoint variables of the study performed in a metabolic unit.
The patients were similar among the 3 groups, had diarrhea for 50–64 hours prior to admission, and were dehydrated when admitted
to the unit for study. Half of the patients in each group were well nourished and the others had mild to moderate degrees
of malnutrition. Rotavirus infection was the agent causing the illness in 63% of the patients. The infants fed juice ingested
14–17% more calories than those given WA, (those receiving AJ and WGJ ingested 95 and 98 Calories/Kg/d respectively) whereas
those receiving WA consumed 81 cal/kg/d). The increased energy intake was not at the expense of other foods or milk formula.
The mean body weight gain was greater among patients receiving WGJ (+ 50.7 gm) as compared with the patients in the AJ group
(+ 18.3 gm) or the patients fed WA (- 0.7 gm) (p = 0.08). The duration of the illness was longer in the infants fed juice
as compared with those given WA (p = 0.006), the mean +/- SD duration in hours was 49.4 ± 32.6, 47.5 ± 38.9 and 26.5 ± 27.4
in patients fed AJ, WGJ and WA respectively. All patients improved while ingesting juice and none of them developed persistent
diarrhea; most recovered within 50 hours of the beginning of treatment and less than one fourth had diarrhea longer than 96
hours in the unit. The fecal losses were also increased among the juice fed patients (p = 0.001); the mean ± SD fecal excretion
in g/kg/h was 3.94 ± 2.35, 3.59 ± 2.35, and 2.19 ± 1.63 in AJ, WGJ and WA respectively. The stool output was highest during
the first day of treatment among all the patients, though those fed AJ had the highest volume of fecal losses and those who
received WA had the lowest stool excretion. After the first day of treatment the differences in fecal excretion were not significant.
The ability to tolerate carbohydrates during the illness and immediately after recovery was similar among the 3 groups of
patients. Intake of juices with different fructose/glucose ratios and osmolarities resulted in more fecal losses and more
prolonged diarrhea as compared with water feedings, but the patients given juice ingested more calories and gained more weight,
particularly among those being fed the juice with equimolar concentrations of fructose and glucose. 相似文献
93.
Josué Garcia Quini Alessandra de Souza Maia Renata Diana Miotti Tereza Silva Martins Wanda de Oliveira 《中国稀土学报(英文版)》2007,25(2):135-138
The synthesis of organolanthanide compounds identified as LnCp*(MS)2PzA, Ln=Sm, Tb, Yb (MS=methanesulfonate, Cp*=pentamethylcyclopentadienyl, and PzA=pyrazinamide), by the reaction of coordination compounds Ln(MS)3(PzA)4 with NaCp in THF was reported. The complexes were formulated according to elemental analyses, complexometric titration with EDTA (%Ln), and 1H NMR. IR spectroscopy revealed that PzA coordinates with lanthanide(Ⅲ) ions and methanesulfonate coordinates via oxygen atoms in a non-equivalent manner. In preliminary catalytic studies, these compounds were active in styrene polymerization that used MAO as a cocatalyst with an activity of 12.3 kg PS mol Sm-1h-1. Differential scanning calorimetry (DSC) of polystyrene showed that the polymer was mainly atactic. 相似文献
94.
Tereza Kostlánová 《Electrochimica acta》2007,52(5):1847-1856
The effect of the inner particle structure on Li insertion activity and electronic structure of the nano-crystalline Li-Ti-O spinels was studied on materials prepared by solid state and solvothermal synthesis. The high temperature prepared materials of composition corresponding to Li4Ti5O12 feature particles with characteristic size of ca. 200 nm with randomly distributed defects. The products of solvothermal synthesis with composition Li1.1Ti1.9O4+δ, feature cubic particles of characteristic dimension of ca. 50 nm; the characteristic particle size differs from that of the coherent domain determined by X-ray diffraction. The reduction of the solvothermal and high temperature synthesized nano-crystalline spinels in Li containing solutions leads according to 6Li MAS NMR spectra to Li insertion into tetrahedral 8b and octahedral 16c position, respectively. Additional broad NMR signal attributable to a Knight shift was observed in spectra of partially reduced high temperature spinels. In the case of solvothermal spinels is the Knight shift signal less pronounced and appears only in spectra of samples in which the phase transition occurs on the local level. The UV-vis-NIR spectra of the partially reduced Li-Ti-O spinel samples correspond to expected semiconductor character of Li-Ti-O spinels. Both types of materials are characterized by band gap of 3.8 eV (high temperature spinel) and 3.5 eV (solvothermal material). Partial reduction accompanied with Li insertion causes additional optical transition in the visible to near infrared region, which can be attributed to formation of trivalent Ti, character of which changes with degree of reduction. The behavior observed for partially reduced high temperature spinels is similar to that reported for TiO2 (anatase). The spectral behavior of the partially reduced solvothermal spinels is more complex and reflects suppressed phase transition. 相似文献
95.
Marcos A. Simplício Paulo S.L.M. Barreto Cintia B. Margi Tereza C.M.B. Carvalho 《Computer Networks》2010,54(15):2591-2612
Wireless Sensor Networks (WSNs) have a vast field of applications, including deployment in hostile environments. Thus, the adoption of security mechanisms is fundamental. However, the extremely constrained nature of sensors and the potentially dynamic behavior of WSNs hinder the use of key management mechanisms commonly applied in modern networks. For this reason, many lightweight key management solutions have been proposed to overcome these constraints. In this paper, we review the state of the art of these solutions and evaluate them based on metrics adequate for WSNs. We focus on pre-distribution schemes well-adapted for homogeneous networks (since this is a more general network organization), thus identifying generic features that can improve some of these metrics. We also discuss some challenges in the area and future research directions. 相似文献
96.
Fernanda M. B. Coutinho Tereza C. J. Rocha Ivana L. Mello Denise S. S. Nunes Bluma G. Soares Marcos A. S. Costa 《应用聚合物科学杂志》2005,98(6):2539-2543
High‐cis polybutadiene produced by catalyst systems based on a rare earth is an elastomer used to produce green tires. This type of tire presents lower rolling resistance, which allows higher fuel economy, and thus fewer chemical compounds are discharged into the atmosphere. In this work, the influence of electron donors [tetrahydrofuran (THF) and tetramethylethylenediamine (TMEDA)] present in the polymerization solvent on the microstructure and molecular weight characteristics of the polybutadiene produced by neodymium catalysts was studied. The catalyst synthesis was carried out in glass bottles for 1 h at a temperature between 5 and 10°C. The catalyst components were diisobutylaluminum hydride, neodymium versatate, and tert‐butyl chloride. The polymerization reaction was carried out for 2 h. The reaction temperature was kept at 70± 3°C. The addition of TMEDA or THF above a determined concentration reduced the catalytic activity, molecular weight, and concentration of cis‐1,4 units (<96%), whereas the polydispersity increased. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2539–2543, 2005 相似文献
97.
Milena pírkov Miroslav louf Olga Blhov Tereza Farka
ov Jaroslava Beneov 《应用聚合物科学杂志》2006,102(6):5763-5774
Surface properties (morphology, hardness) of transparent colorless epoxy‐based organic–inorganic nanocomposite coatings were investigated by atomic force microscopy, optical and scanning electron microscopy, nanoindentation, and the Persoz pendulum test. Friction and wear coefficients were obtained from tribological experiments. The influence of mechanical properties and the size, shape, and concentration of additives (colloidal silica particles and montmorillonite sheets) on the measured surface characteristics are discussed. It was found that the highest surface hardness (assigned by nanoindentation, pendulum test or expressed as the scratch resistance) exhibited materials with the glass‐transition temperature close to 20°C. Microcopy techniques revealed that surface morphology is influenced by both types of admixtures: on the nanometer scale by colloidal silica particles and on micrometer scale by montmorillonite platelets. Already 1 wt % of montmorillonite increased friction coefficients and wear resistance without distinctive changes of tensile properties. However, the addition of ? 20 wt. % of silica nanoparticles was necessary for the increase of wear and scratch resistances. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:5763–5774, 2006 相似文献
98.
Enterobacter sakazakii is an emerging food-borne pathogen causing invasive infection with high mortality rates in neonates and infants. The aim
of this study was to develop, optimize, and evaluate real-time 5′-nuclease polymerase chain reaction (PCR) for the specific
detection and quantification of E. sakazakii. Original primers and TaqMan probe targeting a sequence of E. sakazakii palE gene were designed. The developed real-time PCR system was highly specific for E. sakazakii with 100% inclusivity determined using 54 E. sakazakii strains and 100% exclusivity determined using 99 other strains. Detection limits of 4 × 102 and 4 × 101 CFU ml−1 were determined with 100% and 90% probability, respectively. The response of the 5′-nuclease PCR system was linear (correlation
coefficient ≥ 0.997) in the range of 101 to 108 CFU ml−1. Five methods of DNA sample preparation were compared. The methods of DNA preparation using the InstaGene Matrix and the
simple lysis by boiling with the Triton X-100 were the most sensitive with calibration lines applicable for quantification.
The developed real-time PCR targeted to the palE gene provides an alternative possibility for the detection and quantification of E. sakazakii after the suitable sample preparation. 相似文献
99.
Marcel Karabín Tereza Hudcová Lukáš Jelínek Pavel Dostálek 《Comprehensive Reviews in Food Science and Food Safety》2016,15(3):542-567
Although female cones of the hop plant (Humulus lupulus) are known primarily as raw material supplying characteristic bitterness and aroma to beer, their equally significant health‐promoting effects have been known to mankind for several thousand years and hop is a plant traditionally utilized in folk medicine. This paper summarizes the scientific knowledge on the effects of all 3 major groups of secondary metabolites of hops; polyphenols, essential oils, and resins. Because of their chemical diversity, it is no coincidence that these compounds exhibit a wide range of pharmacologically important properties. In addition to antioxidant, anti‐inflammatory, and anticancer‐related properties, particular attention is being paid to prenylflavonoids that occur almost exclusively in hops and are considered to be some of the most active phytoestrogens known. Hop oils and resins are well known for their sedative and other neuropharmacological properties, but in addition, these compounds exhibit antibacterial and antifungal effects. Recently, alpha bitter acids have been shown to block the development of a number of complex lifestyle diseases that are referred to by the collective name “metabolic syndrome.” Information presented in this review confirms the significant potential for the use of hops in the pharmaceutical industry and provides an understanding of beer as a natural drink that, although moderately consumed, may become a source of many health‐promoting compounds. 相似文献
100.