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31.
Radiotherapy is one of the most common therapies for treating human cancers. Several studies have indicated that irradiation induces reactive oxygen species (ROS), which play an important role in radiation damage of the cell. It has been shown that Nigella sativa L. (NS) and reduced glutathione (GSH) have both an antiperoxidative effect on different tissues and a scavenger effect on ROS. The purpose of this study was to determine the antioxidant and radio-protective roles of NS and GSH against irradiation-induced oxidative injury in an experimental model. The NS group was administrated NS (1 mL/kg body weight), the GSH group was injected GSH (150 mg/kg body weight) and the control group was given physiologic saline solution (1 mL/kg body weight) for 30 consecutive days before exposure to a single dose of 6 Gy of radiation. Animals were sacrificed after irradiation. Malondialdehyde, nitrate, nitrite (oxidative stress markers) and ascorbic acid, retinol, beta-carotene, GSH and ceruloplasmin (nonenzymatic antioxidant markers) levels and peripheral blood lymphocytes were measured in all groups. There were statistically significant differences between the groups for all parameters (P < 0.05). Whole-body irradiation caused a significant increase in blood malondialdehyde, nitrate and nitrite levels. The blood oxidative stress marker levels in irradiated rats that were pretreated with NS and GSH were significantly decreased; however, non-enzymatic antioxidant levels were significantly increased. Also, our results suggest that NS and GSH administration prior to irradiation prevent the number of alpha-naphthyl acetate esterase peripheral blood T lymphocytes from declining. These results clearly show that NS and GSH treatment significantly antagonize the effects of radiation. Therefore, NS and GSH may be a beneficial agent in protection against ionizing radiation-related tissue injury. 相似文献
32.
This study applies fuzzy sets to integrate the supply chain network of an edible vegetable oils manufacturer. The proposed fuzzy multi-objective linear programming model attempts to simultaneously minimize the total transportation costs. The first part of the total transportation costs is between suppliers and silos; and rest one is between manufacturer and warehouses. The approach incorporates all operating realities and actual flow patterns at production/distribution network with reference to demands of warehouses, capacities of tin and pet packaging lines. The model has been formulated as a multi objective linear programming model where data are modeled by triangular fuzzy numbers. Finally, the developed fuzzy model is applied for the case study, compiled the results and discussed. 相似文献
33.
By using new solutions of nonlinear partial differential equation, a direct algebraic method is described to construct the exact traveling wave solutions for perturbed nonlinear Schrödinger's equation (NLSE). Exact traveling wave solutions are explicitly obtained by this method. 相似文献
34.
O. Karabulut M. Parlak R. Turan U. Serincan E. Tasarkuyu B. G. Aknoglu 《Crystal Research and Technology》2003,38(9):811-916
N‐implantation to GaSe single crystals was carried out perpendicular to c‐axis with ion beam of 6 × 1015 ions/cm2 dose having energy values 30 keV and 60 keV. Temperature dependent electrical conductivities and Hall mobilities of implanted samples were measured along the layer in the temperature range of 100‐320 K. It was observed that N‐implantation decreases the resistivity values down to 103 Ω‐cm depending on the annealing temperature, from the room temperature resistivity values of as‐grown samples lying in the range 106‐107 Ω‐cm. The temperature dependent conductivities exhibits two regions (100‐190 and 200‐320 K) with the activation energies of 234‐267 meV and 26‐74 meV, for the annealing temperatures of 500 and 700 °C, respectively. The temperature dependence of Hall mobility for the sample annealed at 500 °C shows abrupt increase and decrease as the ambient temperature increases. The analysis of the mobility‐temperature dependence in the studied temperature range showed that impurity scattering and lattice scattering mechanisms are effective at different temperature regions with high temperature exponent. Annealing of the samples at 700 °C shifted impurity scattering mechanism toward higher temperature regions. In order to obtain the information about the defect produced by N‐implantation, the carrier density was analyzed by using single donor‐single acceptor model. We found acceptor ionization energy as Ea = 450 meV, and acceptor and donor concentration as 1.3 × 1013 and Nd = 3.5 × 1010 cm−3, respectively. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
35.
The influence of initial tension or compression along cracks on the stress intensity factor (SIF) at crack tips under the action of additional normal forces on crack edges is studied for infinite bodies. A strip made of a composite material is considered. The strip ends are simply supported, and the strip contains a crack whose edges are parallel to its face planes. The strip is first stretched or compressed along crack edges, and then additional uniformly distributed normal forces are applied to the crack edges. The influence of the initial tension (compression) on the SIF caused by the additional normal forces is studied. The corresponding boundary-value problems are modelled with the use of the three-dimensional linearized theory of elasticity. All the investigations are carried out numerically by employing the finite-element method. The values of SIF are calculated by the energy release method. 相似文献
36.
Let E, F be Archimedean Riesz spaces. We consider operators that map ideals of E to ideals of F and operators T for which, T
–1 (I) is an ideal in E, for each ideal I in F. We study the properties of such operators and investigate their relation to disjointness preserving operators. 相似文献
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Turan Nevin Buldurun Kenan Alan Yusuf Savci Ahmet Çolak Naki Mantarcı Asim 《Research on Chemical Intermediates》2019,45(6):3525-3540
Research on Chemical Intermediates - In this study, the complex combinations of Ru(II), Co(II) and Ni(II) with Schiff base obtained through the condensation of (E)-methyl... 相似文献
40.
In this study, structural and optoelectronic properties and photodedection characteristics of diodes constructed from p-zinc telluride (ZnTe) thin film/n-silicon (Si) nanowire heterojunctions are reported. Dense arrays of vertically aligned Si nanowires were successfully synthesized on (1 1 0)-oriented n-type single crystalline Si wafer using simple and inexpensive metal-assisted etching (MAE) process. Following the nanowire synthesis, p-type ZnTe thin films were deposited onto vertically oriented Si nanowires via radio frequency magnetron sputtering to form three-dimensional heterojunctions. A comparative study of the structural results obtained from X-ray diffraction and Raman spectroscopy measurements showed the improved crystallinity of the ZnTe thin films deposited onto the Si nanowire arrays. The fabricated nanowire-based heterojunction devices exhibited remarkable diode characteristics and enhanced optoelectronic properties and photosensitivity in comparison to the planar reference. The electrical measurements revealed that the diodes with nanowires had a well-defined rectifying behaviour with a rectification ratio of 104 at ±2 V and a relatively small ideality factor of n = 1.8 with lower reverse leakage current and series resistance at room temperature in dark condition. Moreover, an open-circuit voltage of 100 mV was also observed under illumination. Based on spectral photoresponsivity measurements, the nanowire-based device exhibited a distinct responsivity and high detectivity in visible and near-infrared (NIR) wavelength regions. The device characteristics observed here offer that the fabricated ZnTe thin film/Si nanowire-based p–n heterojunction structures will find important applications in future and will be a promising candidate for high-performance and low-cost optoelectronic device applications, NIR photodedectors in particular. 相似文献