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61.
Alicja Kalinowska-Lyszczarz Jacek Losy 《International journal of molecular sciences》2012,13(10):13713-13725
Multiple sclerosis (MS) is a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system (CNS) with unknown etiology. It was recently suggested that autoimmunity, which had long been considered to be destructive in MS, might also play a protective role in the CNS of MS patients. Neurotrophins are polypeptides belonging to the neurotrophic factor family. While neurotrophins mediate cell survival and proliferation in the nervous system, they are also expressed within peripheral blood mononuclear cells fraction (PBMCs) of immunological system. In MS additional neurotrophic support from PBMCs might compensate relative neurotrophins deficiency in the damaged CNS tissue that needs to be repaired. Failure to produce the adequate neurotrophins concentrations might result in decreased protection of the CNS, consequently leading to increased atrophy, which is the main determinant of MS patients’ end-point disability. There are several lines of evidence, both from clinical research and animal models, suggesting that neurotrophins play a pivotal role in neuroprotective and neuroregenerative processes that are often defective in the course of MS. It seems that neuroprotective strategies might be used as potentially valuable add-on therapies, alongside traditional immunomodulatory treatment in multiple sclerosis. 相似文献
62.
Polyetherols containing a thermally stable pyrimidine ring were obtained upon the reaction of hydroxymethyl derivatives of barbituric acid with an excess of ethylene or propylene oxide. The reaction was monitored by 1H‐NMR and IR spectroscopy for the systems with variable starting molar ratios of reagents. We found that formaldehyde rearranged from N‐hydroxymethyl and oxymethylene bridges into the end of the polyetherol chain during the reaction. Simultaneously, the O‐hydroxymethyl groups underwent blocking by oxirane. The structures of the polyetherols was deduced on the basis of the course of the reaction and the analytical data. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
63.
A parallel algorithm evaluating the reliability of a system with known minimal cuts (paths) 总被引:1,自引:0,他引:1
A system with known minimal cuts is considered. In order to compute its reliability a binary tree is constructed with nodes being assigned numerical values. The value of each non-leaf node is a linear combination of its child nodes' values. The values of leaf nodes can be computed in a very simple way. The value of the root node is the system's reliability. The presented method is a memory saving one. Moreover, it is possible to apply parallel computation to the nodes located on the same level, which may significantly reduce the computing time. 相似文献
64.
Jacek Słupski Jacek Achrem‐Achremowicz Zofia Lisiewska Anna Korus 《International Journal of Food Science & Technology》2010,45(8):1682-1688
The aim of this work was to evaluate the effect of processing on the amino acid content and protein quality of New Zealand spinach (Tetragonia tetragonioides Pall. Kuntze). In this research, fresh and cooked New Zealand spinach as well as two frozen products prepared for consumption, one obtained using the traditional method (blanching–freezing–storage–cooking) and the other a convenience food product obtained using a modified process (cooking–freezing–storage–defrosting and heating in a microwave oven), were analysed. Glutamic acid was the dominant amino acid in fresh New Zealand spinach, and the limiting amino acids were cystine and methionine. Technological and culinary processing caused a significant increase in amino acid content in 100 g of edible portion, with the exception of methionine and cystine in frozen products prepared for eating. Changes in amino acid content expressed in g/16 g of N (which corresponded to 100 g tissue protein) were not significant, with the exception of the lower glutamic acid content in the frozen product obtained using traditional processing method. 相似文献
65.
Rados?aw Bandomir Mariusz Krawczyk Jacek Namie?nik 《Journal of Automated Methods and Management in Chemistry》2005,2005(2):55-57
We present the results of a first stage of development work on a new type of analyzer for hydrogen and C1–C3 hydrocarbons concentration measurements in the lower explosive limit range, based on single pellistor sensor with artificial neural network data postprocessing. 相似文献
66.
A two-way circular consecutively connected system with multistate components (two-way circular CCSMC) consists of n cyclically ordered components e1,…,en, i.e. ei+1, succeeds e1, iε«ng l, …, n − 1ång;, e, succeeds en- Each component is capable of sending a signal in left-hand and right-hand directions. All components operate independently. The whole system is functioning if both left-hand and right-hand signals are received by each component. A recursive procedure evaluating the reliability of a two-way circular CCSMC is presented. 相似文献
67.
The experimental material was a myofibrillar preparation obtained from mechanically recovered poultry meat by the washing
and separation of fat and connective tissues. Changes occurring during frozen storage were investigated in the preparation
without and with the addition of the following substances: 2 g/kg carrageen, 2.5 g/kg sodium tripolyphosphate (TPP) mixture
and 80 g/kg polydextrose, and 3 g/kg enzymatic preparation (ACTIVA WM) containing microbial transglutaminase (MTG). Samples
with the addition of MTG were pre-incubated at the temperature of 7 ± 1 °C for 1, 3, 5, 24 h. All samples were stored at the
temperature of approx. −23 °C for 2, 30, 60, 90 days. The smallest change in protein solubility was observed in samples with
added TPP and polydextrose. Along with the extension of pre-incubation time of samples containing the enzyme a gradual decrease
was found in the amount of soluble protein. Also the results of the investigations obtained using the DSC technique showed
the most advantageous protective effect, i.e., causing the smallest decrease in enthalpy values of samples during freezer
storage, in case of the addition of TPP and polydextrose mixture. Analysis of thermal drip volume from gels showed that carrageen
was the most advantageous addition to the myofibrillar preparation. Moreover, a gradual increase was observed in the volume
of thermal drip along with the extension of pre-incubation time of the protein isolate with enzymatic preparation. Results
of gel texture testing indicated that the most advantageous effect on gel quality was found for ACTIVA applied in 3 and 5 h
pre-incubation with the myofibrils. Assuming that among the analyzed properties the most important were thermal drip and gel
texture, 3 g/kg MTG at pre-incubation time of 3 h was considered the most advantageous additive. 相似文献
68.
Janicka M Kot-Wasik A Kot J Namieśnik J 《International journal of molecular sciences》2010,11(11):4631-4659
Isoprostanes (IsoPs) are key biomarkers for investigating the role of free radical generation in the pathogenesis of human disorders. To solve IsoPs-related problems with regard to isoprostanes, analytical tools are required. This paper reviews the problems and trends in this field focusing on the methodology for assaying biomarkers in exhaled breath condensate (EBC) samples. A large amount of work has been done in the qualitative and quantitative analysis of IsoPs, but a standardized method has yet to emerge. The methodologies described differ, either in the sample preparation steps or in the detection techniques, or both. Requiring a number of chromatographic steps, the relevant extraction and purification procedures are often critical and time-consuming, and they lead to a substantial loss of target compounds. Recent data show that EBC is a promising non-invasive tool for the evaluation of different diseases. Two main analytical approaches have been adopted for IsoPs measurement: immunological methods and mass spectrometry. The methodologies for the extraction, purification and analysis of IsoPs in EBC samples are presented. 相似文献
69.
The demand for ultraviolet (UV)‐crosslinkable pressure‐sensitive adhesives (PSAs) has rapidly been increasing. A variety of different PSAs containing new photoreactive pyridinium derivatives have been evaluated for their effectiveness in improving adhesion and cohesion in UV‐crosslinkable PSAs. PSAs have been evaluated with respect to the tack, peel adhesion, and shear strength. This article summarizes the breakthrough technology used to achieve better performances in UV‐crosslinkable acrylic PSAs. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献
70.
Potential catalysts for the partial oxidation of methane to methanol have been synthesised and tested in high pressure annular reactors. Uranium oxide and molybdenum oxide catalysts and iron sodalite catalyst have been tested under the conditions reported in the patents and under conditions which allow comparison with reactions carried out in the gas phase. None of the catalysts tested showed an improvement on the gas phase results. It was found that the oxidative nature of the metal oxide catalysts is an inherent feature which reduces the selectivity to methanol. 相似文献