Publications by authors named "Helong Liu"

This paper studies a stochastic HIV/AIDS model with nonlinear incidence rate. In the model, the infection rate coefficient and the natural death rates are affected by white noise, and infected people are affected by an intervention strategy. We derive the conditions of extinction and permanence for the stochastic HIV/AIDS model, that is, if $ R_0^s < 1, $ HIV/AIDS will die out with probability one and the distribution of the susceptible converges weakly to a boundary distribution; if $ R_0^s > 1 $, HIV/AIDS will be persistent almost surely and there exists a unique stationary distribution.

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A novel oral drug delivery system, TPGS modified docetaxel proniosomes (DTX-TPGS-PNs), was designed to enhance the oral bioavailability and antitumor efficiency of the poorly water-soluble drug docetaxel. DTX-TPGS-PN niosomes were 93 ± 6.5 nm in size, -18.

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A novel oral delivery system that TPGS modified docetaxel proniosomes, DTX-TPGS-PN, was developed and the characterization after hydration was observed. Firstly, Doce-TPGS-PN was optimized by investing the factors, including the type of surfactant, methods of adding TPGS, content of TPGS and the molar ratio of span40/cholesterol, which may affecting the particle size, encapsulation efficiency and instantaneous release of drug in the formulation. Then, the morphology, particle size, Zeta potential, encapsulation efficiency and in vitro release of the formulation were evaluated.

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In this paper, we develop an HIV model that considers the dependence of HIV/AIDS progress on infection age (duration since infection), chronological age and impulsive antiretroviral treatment. The analytical results show that there exists a globally asymptotically stable infection-free state when the impulsive period T and drug-treatment proportion p satisfy R(0)(p,T)<1. The numerical simulation results indicate that there exist T and p such that R(0)(p,T)<1.

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