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81.
Abnormal glycosylation of cancer cells is considered a key factor of carcinogenesis related to growth, proliferation, migration and invasion of tumor cells. Many plant-based polyphenolic compounds reveal potential anti-cancer properties effecting cellular signaling systems. Herein, we assessed the effects of phenolic acid, p-coumaric acid and flavonoids such as kaempferol, astragalin or tiliroside on expression of selected cancer-related glycoforms and enzymes involved in their formation in AGS gastric cancer cells. The cells were treated with 80 and 160 µM of the compounds. RT-PCR, Western blotting and ELISA tests were performed to determine the influence of polyphenolics on analyzed factors. All the examined compounds inhibited the expression of MUC1, ST6GalNAcT2 and FUT4 mRNAs. C1GalT1, St3Gal-IV and FUT4 proteins as well as MUC1 domain, Tn and sialyl T antigen detected in cell lysates were also lowered. Both concentrations of kaempferol, astragalin and tiliroside also suppressed ppGalNAcT2 and C1GalT1 mRNAs. MUC1 cytoplasmic domain, sialyl Tn, T antigens in cell lysates and sialyl T in culture medium were inhibited only by kaempferol and tiliroside. Nuclear factor NF-κB mRNA expression decreased after treatment with both concentrations of kaempferol, astragalin and tiliroside. NF-κB protein expression was inhibited by kaempferol and tiliroside. The results indicate the rationality of application of examined polyphenolics as potential preventive agents against gastric cancer development.  相似文献   
82.
Journal of Mechanical Science and Technology - In this paper the computational methodology for evaluating vibro-isolation properties of the vibration reduction systems is discussed. The proposed...  相似文献   
83.
Williams BP  Tomczyk S 《Applied optics》1996,35(33):6494-6503
The magneto-optic Doppler analyzer (MODA) is a new type of passive optical instrument that one can use to measure the Doppler shift of the sodium nightglow emitted at approximately 91 km near the mesopause. From this measurement, horizontal wind signatures are inferred. The MODA is based on a sodium vapor magneto-optic filter that provides inherent wavelength stability at a low cost. The instrument has been used to take nightly zonal and meridional wind measurements since October 1994 at Niwot Ridge, Colorado (40 °N, 105 °W). We obtained an internally consistent wind signal and measured the semidiurnal tide for several seasons.  相似文献   
84.
In cell or tissue engineering, it is essential to develop a support for cell-to-cell adhesion, which leads to the generation of cell sheets connected by extracellular matrix. Such supports must be hydrophobic and should result in a detachable cell sheet. A thermoresponsive support that enables the cultured cell sheet to detach using only a change in temperature could be an interesting alternative in regenerative medicine. The aim of this study was to evaluate plates covered with thermoresponsive polymers as supports for the formation of fibroblast sheets and to develop a damage-free procedure for cell sheet transfer with the use of membranes as transfer tools. Human skin fibroblasts were seeded on supports coated with a thermoresponsive polymer: commercial UpCell? dishes (NUNC?) coated with thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) and dishes coated with thermoresponsive poly(tri(ethylene glycol) monoethyl ether methacrylate) (P(TEGMA-EE)). Confluent fibroblast sheets were effectively cultured and harvested from both commercial PNIPAM-coated dishes and laboratory P(TEGMA-EE)-coated dishes. To transfer a detached cell sheet, two membranes, Immobilon-P® and SUPRATHEL®, were examined. The use of SUPRATHEL for relocating the cell sheets opens a new possibility for the clinical treatment of wounds. This study established the background for implementing thermoresponsive supports for transplanting in vitro cultured fibroblasts.  相似文献   
85.
In this paper, we presents an analytical link capacity and outage performance analysis of downlink multiuser diversity (MUD) in multiple-input multiple-output (MIMO) system employing maximal-ratio combining (MRC) with transmit antenna selection (TAS) in the presence of imperfect channel state information (CSI) due to feedback delay over Rayleigh fading channels. The unified achievable analysis is appropriate for MUD–MIMO with TAS/MRC systems in which effective output signal-to-noise ratio (SNR) is specified as highest order statistic of chi-square distribution. Based on this framework, the closed-form channel capacity and outage probability expressions are examined for the MUD–MIMO exploiting TAS/MRC with normalized SNR based scheduling in heterogeneous wireless networks. Further, we derive approximate upper bound capacity as well as capacity at high SNR and low SNR region under delayed feedback CSI. The upper and lower bound of outage probability under delayed feedback CSI is also evaluated. Thereafter the impact of feedback delay and antenna structures with significance on the consideration of MUD on the performance of the system has been analyzed.  相似文献   
86.
The present investigation was designed to determine the meat nutritional profile of European beaver (Castor fiber L.). The proximate composition, energy value, amino acids composition, chemical scores for indispensable amino acids, fatty acids composition and mineral concentrations were determined. In 100 g of meat the content for moisture ranged from 75.42 to 77.32 g, for protein from 20.21 to 22.33 g, for fat from 0.66 to 2.44 and for ash from 1.12 to 1.24 g. The Nutritional Quality Index for muscle protein was 9. The indispensable amino acids (IAA) at the highest content were lysine and leucine (1.85 and 1.65 g 100 g?1). The average percentage of IAA was 45% and their chemical scores amounted to more than 100. The total percentages of trans-, saturated (SFA), mono, and polyunsaturated (PUFA) fatty acids were 2.25, 32.25, 18.83 and 49.08%. The ratio of PUFA/SFA and n-6/n-3 PUFA were 1.56 and 5.58. The cholesterol content averaged 55.10 mg 100 g?1. The muscle tissue of beavers contained favourable amount of minerals, particularly Fe and heme Fe (64.49 and 45.60 mg kg?1), Zn and Cu (45.07 and 0.98 mg kg?1), as well a low level of Na (461.9 mg kg?1). Summing up, beavers are a valuable nutritional meat source with a desirable chemical composition and a low calorific value and can constitute a healthy alternative food as advantageous for human health and coherent with diet recommendations.  相似文献   
87.
A nonionic sunflower oil-aqueous ethanol microemulsion was formulated, characterized and evaluated as a fuel in a direct injection, turbocharged, intercooled, 4-cylinder Allis-Chalmers diesel engine during a 200 hr EMA cycle laboratory screening endurance test. Differences in engine operation between a baseline Phillips 2D reference fuel and the experimental fuel were observed. The major problem experienced while operating with the microemulsion was an incomplete combustion process at low-load engine operation. Significant lubricating oil dilution was observed initially, followed by an abnormal increase in the viscosity of the lubricative oil. Heavier carbon residue on the piston lands, in the piston ring grooves and in the intake ports was noted. In addition, premature injection-nozzle deterioration (sticking of the needle) was experienced. At present, the sunflower oil-aqueous ethanol microemulsion studied cannot be recommended for long-term use in a direct-injection diesel engine, but further modifications in formulation may produce acceptable sunflower oil microemulsions as alternative diesel fuels. Presented at the AOCS meeting, Chicago, IL, May 1983.  相似文献   
88.
The oxygen electrode reaction at the interface gold∣yttria stabilized zirconia was investigate using microelectrodes by chronoamperometry and electrochemical impedance spectroscopy, with emphasis put on effect of prolonged polarization of the electrode. Two interesting phenomena were observed: (a) generally, the long-lasting negative polarization resulted in a slow monotonous decrease of the current flowing through the electrode, (b) the reaction mechanism was less complicated for the polarized then unpolarized electrodes, which resulted in a relatively simply equivalent circuit used for modelling the former ones. On the basis of the data obtained, the apparent exchange currents normalized vs. the three phase boundary length and Tafel slopes were determined. The methods of determining the three phase boundary length were discussed. The reconnaissance data obtained for the Pt microelectrode are also reported.  相似文献   
89.
90.
We propose a mixed-integer programming (MIP) formulation for a problem of optimal dimensioning of equipment of the fiber-to-the-home optical access network (FTTH-OAN). The optimization aims at minimizing capital expenditures (CAPEX) related to deployment of the FTTH-OAN, i.e., the cost of active equipment (OLTs and OLT cards), cost of passive equipment (optical splitters, cables, fibers, fibers terminations, splices, closures), cost of site preparations (building, cabinets), and cost of necessary labor (duct preparation and rollout of cables). The formulation has been implemented and validated. General results based on selected real-world scale numerical experiments are presented.  相似文献   
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