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1.
Our aim was to investigate the subset distribution and function of circulating monocytes, proinflammatory cytokine levels, gut barrier damage, and bacterial translocation in chronic spinal cord injury (SCI) patients. Thus, 56 SCI patients and 28 healthy donors were studied. The levels of circulating CD14+highCD16, CD14+highCD16+, and CD14+lowCD16+ monocytes, membrane TLR2, TLR4, and TLR9, phagocytic activity, ROS generation, and intracytoplasmic TNF-α, IL-1, IL-6, and IL-10 after lipopolysaccharide (LPS) stimulation were analyzed by polychromatic flow cytometry. Serum TNF-α, IL-1, IL-6 and IL-10 levels were measured by Luminex and LPS-binding protein (LBP), intestinal fatty acid-binding protein (I-FABP) and zonulin by ELISA. SCI patients had normal monocyte counts and subset distribution. CD14+highCD16 and CD14+highCD16+ monocytes exhibited decreased TLR4, normal TLR2 and increased TLR9 expression. CD14+highCD16 monocytes had increased LPS-induced TNF-α but normal IL-1, IL-6, and IL-10 production. Monocytes exhibited defective phagocytosis but normal ROS production. Patients had enhanced serum TNF-α and IL-6 levels, normal IL-1 and IL-10 levels, and increased circulating LBP, I-FABP, and zonulin levels. Chronic SCI patients displayed impaired circulating monocyte function. These patients exhibited a systemic proinflammatory state characterized by enhanced serum TNF-α and IL-6 levels. These patients also had increased bacterial translocation and gut barrier damage.  相似文献   
2.
Reactivity to Alcohol and Neutral Cues was compared in male, inpatient problem drinkers (N = 30). Subjects reported an overall desire not to drink alcohol which decreased in the presence of the Alcohol Cue. There were no cue-specific changes in heart rate, blood pressure and arousal level and a non-significant trend for increased stress in the Alcohol Cue condition. Subgroups of subjects reporting positive and negative desire for alcohol were identified. Subjects who reported negative desire for alcohol in the Alcohol Cue condition also reported greater self-efficacy to resist drinking in the future. These findings have implications for understanding the nature of self-reported desire for alcohol and its potential role in the treatment of alcohol dependence.  相似文献   
3.
The relationship between manometric and pH-metric data was studied in a group of 50 patients with symptoms of gastroesophageal reflux. Using a multiple regression analysis, we found that the total percentage of reflux was significantly correlated to the infradiaphragmatic length and resting pressure of the lower esophageal sphincter and also to the mean amplitude of the contractile waves of the distal esophagus, thus revealing the important role of these factors in the antireflux mechanism. When the patients were divided into groups according to their manometric characteristics and the values of the various pH-metric parameters between these groups compared using a one-way analysis of variance, we found that the amplitude of the contractile waves and the percentage of deglutitions without response were related not only to the total percentage of reflux but also to the number of reflux episodes of greater than 5 min duration and to the duration of the longest episode. This shows that prolonged exposure of the esophageal mucosa to the refluxed material may be due, in part, to an alteration in the capacity for esophageal clearing.  相似文献   
4.
Four polynomial expressions are obtained that provide a good approximation and an easy, rapid calculation of the chromatic coordinates and the chroma—L *, a *, b *, and C—for the illuminant C and the standard observer, for a virgin or extra virgin olive oil; absorbance is measured at only 480 and 670 nm. These are as follows: L *=0.556458(A480)2−2.51145A480+0.55504(A670)2−8.53016A670+98.4089; a *=0.177372(A480)2+2.1363A480+1.43254(A670)2−0.789231A670−13.9246; b *=−16.0277(A480)2+79.8932A480−5.06558(A670)2+3.36169A670+31.9405; C=−15.8439(A480)2+78.9312A480−5.26784(A670)2+3.56917A670+33.3927. These give acceptable results, making the method a practical alternative to the extremely laborious Commission Internationale d’Eclairage (CIE) L * a * b * system, by which 391 absorbance values must be measured individually, nanometer by nanometer, before applying more complex equations. The validity of the proposed method has been confirmed by comparison, using a set of 20 sample oils different from the set of 25 oils used to generate the order of the equations. The variations between the values provided by the proposed and standard methods, respectively, had a mean of 0.00 for each of the chromatic variables—L * , a * , b * , and C; SD were moderate (0.71, 0.52, 1.22, and 1.22, respectively); the root mean square and the R 2-terms also confirmed the validity of the method.  相似文献   
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6.
Catalysis Letters - Alkynes are one of the most important groups of building blocks in organic chemistry as they work as nucleophiles upon deprotonation of its acidic hydrogen. On the surface of a...  相似文献   
7.
For pt.I, see Sanchez, M.G. et al., ibid., p.111-15. The results of an extensive study on analog PAL signals interfered with by digital DVB-T signals are presented. The study covers a theoretical evaluation of the interference problems, field and laboratory measurements and a national survey among TV installation companies. Field measurements are reported in part I. These measurements explain the origin of cochannel and some of the adjacent channel interference problems. However, interference was reported in areas where the field measurements showed that the protection ratios for PAL signals interfered with by DVB-T adjacent channel signals were met. As these reports came from multistorey buildings with master antenna TV (MATV) installations, the study was extended to analyze the role of these installations in the interference problems. Part of the interference problems are due to the MATV system amplifiers which are unable to cope with adjacent channel DVB-T signals. The nonlinear amplifiers give rise to intermodulation problems. The ITU-R recommendations (see ITU-R BT.1368, 2000) recognize that such nonlinear amplifiers could be a source of problems and that higher protection ratios may be needed, but no value is given for the increase. Our laboratory tests of commercial amplifiers found that an increase in the protection ratios of between 12 to 16 dB is needed to avoid a significant degradation of the PAL TV signal in the amplifiers. It has also been found that most of the interference situations are not due to the interfering signal being a DVB-T format, but that any significant signal amplitude in the passband of the filter causes interference. Therefore, MATV system distribution needs planning factors associated with the distribution of any signals near the main signal. The results are presented of a survey conducted among companies who install communal telecommunication infrastructures in Spain.  相似文献   
8.
The uplink capacity and the interference statistics (mean and variance) of the sectors of the cigar-shaped W-CDMA microcell are studied. A model with eighteen sectors is used to analyze the uplink. The microcells are assumed to exist in a long tunnel with at least nine base stations. The hybrid model of propagation is used in the calculations. The capacity and the interference statistics of the sectors are studied in terms of the most important parameters: sector radius, specific attenuation factor, antenna sidelobe levels, bend losses and the power control standard deviation error.  相似文献   
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10.
Effects of Dry Grinding on the Structural Changes of Kaolinite Powders   总被引:2,自引:0,他引:2  
The present study examined the effects of dry grinding, using ball-milling, on the structure of reference well-crystallized (KGa-1) and poorly crystallized (KGa-2) kaolinite powders from Georgia. Grinding produced a strong structural alteration, mainly along the c axis, resulting in disorder and total degradation of the crystal structure of the kaolinite and the formation of an amorphous product. The surface area increased with grinding time, mainly in KGa-2 (maximum value 50.27 m2/g), a result associated with particle-size reduction. These particles became more agglomerated with grinding, and the surface area decreased after 30 min, as confirmed by scanning electron microscopy and particle-size-distribution analysis. There was a limit to particle-size reduction with grinding time. When grinding time was increased, the original endothermic differential thermal analysis (DTA) effects of dehydroxylation in both samples shifted to lower temperatures, decreased in intensity, then disappeared completely after 120 min of grinding. The temperature of the characteristic first exothermic effect shifted slightly to lower temperatures with grinding, although the DTA effects did not increase with grinding time in either kaolinite sample, at least up to 325 min. The amorphous, mechanically activated kaolinite converted into low-crystalline mullite nuclei at a lower temperature than did the unground samples, as deduced by thermal and X-ray observations. This effect was especially important for the KGa-2 sample. Grinding did not seem to influence the formation of silicon-aluminum spinel from kaolinite. The present results may explain why ground kaolinite samples prepared via different routes—e.g., with differences in grinding—behave differently during high-temperature transformations, as reported in the related literature.  相似文献   
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