OBJECTIVE:To assess the total and soluble oxalate contents of commonly used Chinese medicinal herbs.METHODS:Twenty-two Chinese medicinal herbs were extracted in both acid and water prior to determination of total and ...OBJECTIVE:To assess the total and soluble oxalate contents of commonly used Chinese medicinal herbs.METHODS:Twenty-two Chinese medicinal herbs were extracted in both acid and water prior to determination of total and soluble oxalate,respectively.Oxalate was assayed in herbal extracts using a well-established enzymatic procedure.RESULTS:Among the 22 medicinal herbs,there was significant variation in oxalate content;Houttuynia cordata contained the highest amount of soluble oxalate(2146 mg/100 g) and Selaginella doederleinii contained the lowest amount(71 mg/100g).CONCLUSION:The results indicated that different Chinese medicinal herbs,even from the same family,contain significantly different amounts of oxalate.In susceptible individuals,the use of medicinal herbs with the highest oxalate contents could increase risk of kidney stone formation.展开更多
Nowadays, biological resource in prey-predator ecosystem is commercially harvested and sold with aim of achieving economic interest. Furthermore, harvest effort is usually influ- enced by variation of economic interes...Nowadays, biological resource in prey-predator ecosystem is commercially harvested and sold with aim of achieving economic interest. Furthermore, harvest effort is usually influ- enced by variation of economic interest of harvesting and spatial heterogeneous environ- ment. In this paper, a delayed differential-algebraic bio-economic model is proposed, which is utilized to investigate interaction and coexistence mechanism of biological pop- ulation in the harvested ecosystem due to the variation of economic interest of harvesting as well as the change of population spatial diffusion and gestation delay. Local stability analysis of the proposed model without gestation delay and diffusion reveals that there is a phenomenon of singularity induced bifurcation due to the variation of economic interest of harvesting, and state feedback controllers are designed to stabilize the pro- posed model at the interior equilibrium. Furthermore, local stability of the proposed model with gestation delay and diffusion is studied, which reveals that the interior equi- librium loses its stability at some critical values of gestation delay and corresponding cycle occurs. It is also shown that population spatial diffusion and harvesting have a stabilizing effect on population dynamics. Finally, numerical simulations are carried out to show consistency with theoretical analysis obtained in this paper.展开更多
文摘OBJECTIVE:To assess the total and soluble oxalate contents of commonly used Chinese medicinal herbs.METHODS:Twenty-two Chinese medicinal herbs were extracted in both acid and water prior to determination of total and soluble oxalate,respectively.Oxalate was assayed in herbal extracts using a well-established enzymatic procedure.RESULTS:Among the 22 medicinal herbs,there was significant variation in oxalate content;Houttuynia cordata contained the highest amount of soluble oxalate(2146 mg/100 g) and Selaginella doederleinii contained the lowest amount(71 mg/100g).CONCLUSION:The results indicated that different Chinese medicinal herbs,even from the same family,contain significantly different amounts of oxalate.In susceptible individuals,the use of medicinal herbs with the highest oxalate contents could increase risk of kidney stone formation.
文摘Nowadays, biological resource in prey-predator ecosystem is commercially harvested and sold with aim of achieving economic interest. Furthermore, harvest effort is usually influ- enced by variation of economic interest of harvesting and spatial heterogeneous environ- ment. In this paper, a delayed differential-algebraic bio-economic model is proposed, which is utilized to investigate interaction and coexistence mechanism of biological pop- ulation in the harvested ecosystem due to the variation of economic interest of harvesting as well as the change of population spatial diffusion and gestation delay. Local stability analysis of the proposed model without gestation delay and diffusion reveals that there is a phenomenon of singularity induced bifurcation due to the variation of economic interest of harvesting, and state feedback controllers are designed to stabilize the pro- posed model at the interior equilibrium. Furthermore, local stability of the proposed model with gestation delay and diffusion is studied, which reveals that the interior equi- librium loses its stability at some critical values of gestation delay and corresponding cycle occurs. It is also shown that population spatial diffusion and harvesting have a stabilizing effect on population dynamics. Finally, numerical simulations are carried out to show consistency with theoretical analysis obtained in this paper.