Objective. The present study was performed to investigate the effect of N-desulfated heparin on basic fibroblast growth factor (bFGF) expression, tumor angiogenesis and metastasis of gastric carcinoma. Methods. Human gastric cancer SGC-7901 tissues were orthotopically implanted into the stomach of NOD SCID mice. Twenty mice were randomly divided into two… (More)
Based on the Eigen and Crow-Kimura models with a single peak fitness landscape, we propose that the fitness values of all molecules be Gaussian distributed random variables to incorporate the fluctuation effects of the fitness landscapes (noise of environments). And we investigate the quasispecies distribution and error threshold using ensemble average… (More)
By means of the nonlinear modeling technique, we find the nonlinear deterministic structures in the totally 4737 Human promoter sequences. These deterministic structures prefer to occur much more outside of a special region around the transcriptional start site. The number and positions of the deterministic structures are basically different for different… (More)
In this paper ITO thin films were deposited on alumina substrates by ultrasonic spray pyrolysis. The NO 2 sensing properties of ITO thin films were investigated. The results show ITO thin films have good sensitivity to nitrogen dioxide.
Species evolution is essentially a random process of interaction between biological populations and their environments. As a result, some physical parameters in evolution models are subject to statistical fluctuations. In this paper, two important parameters in the Eigen model, the fitness and mutation rate, are treated as Gaussian distributed random… (More)
The stochastic Eigen model proposed by Feng et al. (2007) (Journal of Theoretical Biology, 246, 28) showed that error threshold is no longer a phase transition point but a crossover region whose width depends on the strength of the random fluctuation in an environment. The underlying cause of this phenomenon has not yet been well examined. In this article,… (More)
By means of the nonlinear modelling technique, we find the nonlinear deterministic structures in the totally 4737 human promoter sequences. These deterministic structures prefer to occur much more outside of a special region around the transcriptional start site. The number and positions of the deterministic structures are basically different for different… (More)