Based on the Krylov-Bogolyubov method of averaging the closed system of equations for particle motion and temperature in inhomogeneous rapidly oscillating velocity and temperature of fluid phase is derived. It is show...Based on the Krylov-Bogolyubov method of averaging the closed system of equations for particle motion and temperature in inhomogeneous rapidly oscillating velocity and temperature of fluid phase is derived. It is shown that the particle movement in a rapidly oscillating fluid velocity field occurs not only under the force of gravity and resistance, but also under force of migration. The migration force is the result of particle inertia and in homogeneity of oscillation of velocity field of the carrier phase. Effects of dynamic and thermal relaxation times of particle and gravity force have been studied. It is shown possibilities of accumulation of particles under the combined action of gravity and migration forces. For a linear dependence of the amplitude of velocity and temperature fluctuations of the fluid an analytical solution was presented. The analytical solutions have been found in good agreement with the results of numerical solution of system of equations of motion and heat transfer of particle.展开更多
Background:Neuroblastoma is an embryonic neoplasm originating from the neural crest with cellular heterogeneity as one of its oncobiological characteristics.This study was undertaken to determine whether human neurobl...Background:Neuroblastoma is an embryonic neoplasm originating from the neural crest with cellular heterogeneity as one of its oncobiological characteristics.This study was undertaken to determine whether human neuroblastoma contains stem ell-like cells.Methods:Twenty patients with neuroblastoma who have been treated in our hospital since January 2005 were divided into pre-operative chemotherapy(10 patients)and non-chemotherapy(10)groups.Tumor specimens of the patients were taken and paraffin sections were made.The expressions of stem cell markers CD133,ABCG2,CD117 and nestin were immunohistochemically detected in the specimens.Neuroblastoma cells were stained with Hoechst 33342 and PI.The side population(SP)cells were analyzed by the fluorescence activated cell sorter.The disparity drug resistance to cisplatin(DDP)of SP and non-SP cells was measured with MTT colorimetric assay.The oncogenicity of SP and non SP cells was identified in nude mice.Results:There was no significant difference in the expression intensity of CD117 and nestin between the two groups of specimens(P>0.05).There was a significant difference between the two groups in terms of the expression intensity of CD133 and ABCG2(P<0.05).The SP cells accounted for 0.2%-1.3%of the total human neuroblastoma cells and were decreased to 0.1%-0.5%after verapamil treatment.The SP and non-SP cells showed disparity in cell growth experiment and drug resistance to DDP.Oncogenicity experiment revealed that nude mice could erupt tumor by an injection of 1×10^(6)SH-SY5Y and WIV SP cells.However,the nude mice could not form tumor by an injection of 1×10^(6)non-SP cells.Conclusion:Neuroblastoma might contain cancer stem cell-like cells.展开更多
文摘Based on the Krylov-Bogolyubov method of averaging the closed system of equations for particle motion and temperature in inhomogeneous rapidly oscillating velocity and temperature of fluid phase is derived. It is shown that the particle movement in a rapidly oscillating fluid velocity field occurs not only under the force of gravity and resistance, but also under force of migration. The migration force is the result of particle inertia and in homogeneity of oscillation of velocity field of the carrier phase. Effects of dynamic and thermal relaxation times of particle and gravity force have been studied. It is shown possibilities of accumulation of particles under the combined action of gravity and migration forces. For a linear dependence of the amplitude of velocity and temperature fluctuations of the fluid an analytical solution was presented. The analytical solutions have been found in good agreement with the results of numerical solution of system of equations of motion and heat transfer of particle.
基金supported by a grant from the National Natural Science Foundation of China(81272803).
文摘Background:Neuroblastoma is an embryonic neoplasm originating from the neural crest with cellular heterogeneity as one of its oncobiological characteristics.This study was undertaken to determine whether human neuroblastoma contains stem ell-like cells.Methods:Twenty patients with neuroblastoma who have been treated in our hospital since January 2005 were divided into pre-operative chemotherapy(10 patients)and non-chemotherapy(10)groups.Tumor specimens of the patients were taken and paraffin sections were made.The expressions of stem cell markers CD133,ABCG2,CD117 and nestin were immunohistochemically detected in the specimens.Neuroblastoma cells were stained with Hoechst 33342 and PI.The side population(SP)cells were analyzed by the fluorescence activated cell sorter.The disparity drug resistance to cisplatin(DDP)of SP and non-SP cells was measured with MTT colorimetric assay.The oncogenicity of SP and non SP cells was identified in nude mice.Results:There was no significant difference in the expression intensity of CD117 and nestin between the two groups of specimens(P>0.05).There was a significant difference between the two groups in terms of the expression intensity of CD133 and ABCG2(P<0.05).The SP cells accounted for 0.2%-1.3%of the total human neuroblastoma cells and were decreased to 0.1%-0.5%after verapamil treatment.The SP and non-SP cells showed disparity in cell growth experiment and drug resistance to DDP.Oncogenicity experiment revealed that nude mice could erupt tumor by an injection of 1×10^(6)SH-SY5Y and WIV SP cells.However,the nude mice could not form tumor by an injection of 1×10^(6)non-SP cells.Conclusion:Neuroblastoma might contain cancer stem cell-like cells.
