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51.
Margarines and spreads contribute greatly to the intake of saturated and trans fats in the diet. Therefore, the objective of this work was to produce margarines using the oleogel technology and to verify the physical, thermal, oxidative, and sensorial properties of this product during six months of shelf life, comparing it with commercial margarine. When compared with commercial margarine, the oleogel margarine showed similar color results. Due to the different structural shape, the results of microstructure and the melting curve were differentiated, but this indicated a structure more resistant to temperature oscillations and an overall softer product. However, the sensorial difference between the samples was easily detected by the consumers, mainly with respect to the parameters of taste, texture, and overall impression. It was concluded that it is possible to produce margarines using the oleogel technology, which display good physical properties, similar shelf life, and improved nutritional characteristics.  相似文献   
52.
The effectiveness of opioids in the treatment of neuropathic pain is limited. It was demonstrated that magnesium ions (Mg2+), physiological antagonists of N-methyl-D-aspartate receptor (NMDAR), increase opioid analgesia in chronic pain. Our study aimed to determine the molecular mechanism of this action. Early data indicate the cross-regulation of µ opioid receptor (MOR) and NMDAR in pain control. Morphine acting on MOR stimulates protein kinase C (PKC), while induction of NMDAR recruits protein kinase A (PKA), leading to a disruption of the MOR-NMDAR complex and promoting functional changes in receptors. The mechanical Randall-Selitto test was used to assess the effect of chronic Mg2+ and morphine cotreatment on streptozotocin-induced hyperalgesia in Wistar rats. The level of phosphorylated NMDAR NR1 subunit (pNR1) and phosphorylated MOR (pMOR) in the periaqueductal gray matter was determined with the Western blot method. The activity of PKA and PKC was examined by standard enzyme immunoassays. The experiments showed a reduction in hyperalgesia after coadministration of morphine (5 mg/kg intraperitoneally) and Mg2+ (40 mg/kg intraperitoneally). Mg2+ administered alone significantly decreased the level of pNR1, pMOR, and activity of both tested kinases. The results suggest that blocking NMDAR signaling by Mg2+ restores the MOR-NMDAR complex and thus enables morphine analgesia in neuropathic rats.  相似文献   
53.
Polyethylene films coated by commercially available polyvinyldichloride (PVdC) as well as nitrocellulose (NC) lacquer with addition of natamycin preparation Delvocid® (16.7% w/w of natamycin in lacquer) were studied at 6 and 23 °C to determine the preservative migration into distilled water. The films released natamycin at maximal level 2.34 ± 0.32 mg/dm2. The diffusion coefficient of 0.79 × 10−10 ± 0.29 × 10−10 cm2/s and 1.03 × 10−10 ± 0.17 × 10−10 cm2/s was determined for natamycin transport in PVdC lacquer layer at 6 and 23 °C, respectively. For nitrocellulose lacquer the diffusion coefficient of 0.89 × 10−10 ± 0.16 × 10−10 cm2/s was found at 23 °C. The coextruded polyamide/polyethylene film coated with the PVdC lacquer containing both nisin (16.7% w/w of preparation Nisaplin®) and natamycin (see above) provided inhibitory effect against selected indicator microorganisms (Penicillium expansum, Fusarium culmorum, Lactobacillus helveticus, Listeria ivanovií). This film was unsuitable for the packaging of the surface ripened cheese Olomoucké tvar??ky. On the other hand, it was able to prevent the growth of spoilage microorganisms on the surface of the packaged soft cheese Bla?ácké zlato.  相似文献   
54.
The moderating influences of family structure and parent–adolescent distress on the relationship between peer variables and drug use were examined in a predominantly African American sample of 630 10th graders at 9 urban high schools. Both peer pressure and peer drug use were significantly related to the reported frequency of drug use. The relationship between peer pressure and drug use was stronger among girls than boys, and also among adolescents in families without fathers or stepfathers. The association between peer pressure and drug use also increased as a function of the level of mother–adolescent distress among adolescents who were not living with fathers or stepfathers. Neither gender nor family structure moderated the relationship between peer drug models and drug use. However, the association between peer drug models and drug use increased as a function of the level of mother–adolescent distress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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56.
The aim of the study was to assess the biocompatibility profile of a newly developed high-flux polysulfone dialyzer type (FX-class dialyzer). The new class of dialyzers incorporates a number of novel design features (including a new membrane) that have been developed specifically in order to enhance the removal of small- and middle-size molecules. The new FX dialyzer series was compared with the classical routinely used high-flux polysulfone F series of dialyzers. In an open prospective, randomized, crossover clinical study, concentrations of the C5a complement component, and leukocyte count in blood and various thrombogenicity parameters were evaluated before, and at 15 and 60 min of hemodialysis at both dialyzer inlet and outlet in 9 long-term hemodialysis patients using the FX60S dialyzers and, after crossover, the classical F60S, while in another 9 patients, the evaluation was made with the dialyzers used in reverse order. The comparison of dialyzers based on evaluation of the group including all procedures with the FX60S and the group including procedures with the F60S did not reveal significant differences in platelet count, activated partial thromboplastin times, plasma heparin levels, platelet factor-4, D-dimer, C5a, and leukocyte count at any point of the collecting period. Both dialyzer types showed a significant increase in the plasma levels of the thrombin-antithrombin III complexes; however, the measured levels were only slightly elevated compared with the upper end of the normal range. Biocompatibility parameters reflecting the behavior of platelets, fibrinolysis, complement activation, and leukopenia do not differ during dialysis with either the FX60S or the F60S despite their large differences in design and geometry features. Although coagulation activation, as evaluated by one of the parameters used, was slightly higher with the FX60S, it was still within the range seen with other highly biocompatible dialyzers and therefore is not indicative of any appreciable activation of the coagulation system. Thus, the incorporation of various performance-enhancing design features into the new FX class of dialyzers does not result in a deterioration of their biocompatibility profile, which is comparable to that of the classical F series of dialyzers.  相似文献   
57.
The binding of tannin fraction to protein fractions isolated from broad bean seeds was studied by precipitating potential and fluorescence quenching methods. The tannin fraction with high proanthocyanidins content was isolated from broad bean coats. Storage proteins of broad bean, 11S, 7S, and 2S, were isolated from broad bean cotyledons and purified. Gelatin, BSA, as well as broad bean 2S and 7S protein fractions exhibited similar shape of curves illustrating the effect of pH on protein precipitation and were precipitated by broad bean tannin fraction over the wide range of pH. For pea proteins isolate and 11S fraction of broad bean proteins, quite different effect of pH was observed. The relationships between the amount of protein–polyphenols complex precipitated and the content of tannin fraction were linear and characterized by high squared correlation coefficients ranging from 0.9613 to 0.9938. Among the protein fractions isolated from broad bean seeds, the highest precipitating potential was noted for 11S fraction, followed by 7S and 2S fractions and amounted to 1.63, 1.34, and 0.87, respectively. To characterize the association of proteins with phenolic compounds yielding formation of soluble complexes, fluorescence spectroscopy was applied. Similarly, the most extensive fluorescence quenching was observed in the case of 11S protein fraction.  相似文献   
58.
Purinergic signalling plays a crucial role in proper functioning of the nervous system. Mechanisms depending on extracellular nucleotides and their P2 receptors also underlie a number of nervous system dysfunctions. This review aims to present the role of purinergic signalling, with particular focus devoted to role of P2 family receptors, in epilepsy, depression, neuropathic pain, nervous system neoplasms, such as glioma and neuroblastoma, neurodegenerative diseases like Parkinson’s disease, Alzheimer’s disease and multiple sclerosis. The above-mentioned conditions are associated with changes in expression of extracellular ectonucleotidases, P2X and P2Y receptors in neurons and glial cells, as well as releasing considerable amounts of nucleotides from activated or damaged nervous tissue cells into the extracellular space, which contributes to disturbance in purinergic signalling. The numerous studies indicate a potential possibility of using synthetic agonists/antagonists of P2 receptors in treatment of selected nervous system diseases. This is of particular significance, since numerous available agents reveal a low effectiveness and often produce side effects.  相似文献   
59.
The stretch zone width (SZW) data for 15‐5PH steel CTOD specimens fractured at ?150°C to + 23°C temperature were measured based on focused images and 3D maps obtained by extended depth‐of‐field reconstruction from light microscopy (LM) image stacks. This LM‐based method, with a larger lateral resolution, seems to be as effective for quantitative analysis of SZW as scanning electron microscopy (SEM) or confocal scanning laser microscopy (CSLM), permitting to clearly identify stretch zone boundaries. Despite the worst sharpness of focused images, a robust linear correlation was established to fracture toughness (KC) and SZW data for the 15‐5PH steel tested specimens, measured at their center region. The method is an alternative to evaluate the boundaries of stretched zones, at a lower cost of implementation and training, since topographic data from elevation maps can be associated with reconstructed image, which summarizes the original contrast and brightness information. Finally, the extended depth‐of‐field method is presented here as a valuable tool for failure analysis, as a cheaper alternative to investigate rough surfaces or fracture, compared to scanning electron or confocal light microscopes. Microsc. Res. Tech. 75:1155–1158, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
60.
Saturated stearic acid (SA) induces apoptosis in the human pancreatic β-cells NES2Y. However, the molecular mechanisms involved are unclear. We showed that apoptosis-inducing concentrations of SA activate the p38 MAPK signaling pathway in these cells. Therefore, we tested the role of p38 MAPK signaling pathway activation in apoptosis induction by SA in NES2Y cells. Crosstalk between p38 MAPK pathway activation and accompanying ERK pathway inhibition after SA application was also tested. The inhibition of p38 MAPK expression by siRNA silencing resulted in a decrease in MAPKAPK-2 activation after SA application, but it had no significant effect on cell viability or the level of phosphorylated ERK pathway members. The inhibition of p38 MAPK activity by the specific inhibitor SB202190 resulted in inhibition of MAPKAPK-2 activation and noticeable activation of ERK pathway members after SA treatment but in no significant effect on cell viability. p38 MAPK overexpression by plasmid transfection produced an increase in MAPKAPK-2 activation after SA exposure but no significant influence on cell viability or ERK pathway activation. The activation of p38 MAPK by the specific activator anisomycin resulted in significant activation of MAPKAPK-2. Concerning the effect on cell viability, application of the activator led to apoptosis induction similar to application of SA (PARP cleavage and caspase-7, -8, and -9 activation) and in inhibition of ERK pathway members. We demonstrated that apoptosis-inducing concentrations of SA activate the p38 MAPK signaling pathway and that this activation could be involved in apoptosis induction by SA in the human pancreatic β-cells NES2Y. However, this involvement does not seem to play a key role. Crosstalk between p38 MAPK pathway activation and ERK pathway inhibition in NES2Y cells seems likely. Thus, the ERK pathway inhibition by p38 MAPK activation does not also seem to be essential for SA-induced apoptosis.  相似文献   
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