A new bidihydroflavonoid, thuidinin 1, together with 5 known compounds including one known biflavonoid 3',3"'-binaringenin (2) and four other known natural products pentadecane (3), methyl β-orcinolarboxylate ...A new bidihydroflavonoid, thuidinin 1, together with 5 known compounds including one known biflavonoid 3',3"'-binaringenin (2) and four other known natural products pentadecane (3), methyl β-orcinolarboxylate (4), β-sitosterol (5) and daucostenol (6), were isolated from leaves of Thuidium kanedae Sak. Their structures were established on the basis of 1D and 2D spectroscopic analysis. The absolute stereochemistry of compounds 1 and 2 was determined by CD spectra.展开更多
Objective: To study the pharmacokinetics of native r SAK in rabbit's femoral artery thrombosis model, the “lytic circle' method was used to determine plasma levels of r SAK. Methods: Thirty New Zealand rabb...Objective: To study the pharmacokinetics of native r SAK in rabbit's femoral artery thrombosis model, the “lytic circle' method was used to determine plasma levels of r SAK. Methods: Thirty New Zealand rabbits were randomly assigned to the control (saline 10 ml, 30 min), r SAK low dose (0.25 mg/kg, 30 min), medial dose (0.50 mg/kg, 30 min), high dose (1.00 mg/kg, 30 min), single bolus (0.50 mg/kg, 2 min) and conjunctive therapy (initiated with heparin 200 U/kg, followed by infusion of r SAK 0.50 mg/kg for 30 min, and subsequently infused heparin 50 U/(kg·h) to endpoint) groups. The right femoral artery thrombosis model in rabbit was made by balloon injury, then the thrombolytic agents were infused through parallel ear vein and the blood samples were collected pre thrombolysis and at different time post thrombolysis to determine the plasma levels of r SAK by “lytic circle' method, the plasma levels of r SAK were processed by pharmacokinetic computing procedure to fit the model. Results: The plasma levels of r SAK and the diameters of lytic circles showed a pretty good linear correlation under the scope of 2.0×10 4 2.0×10 6 U/L, and the averaged recycle rate was (96.05±11.35)%(RSD =±11.82%).All peak concentration time in each infusion group was 30 min, and the peak concentrations positively correlated with the doses administrated in infusion groups(r=0.999 98, P <0.000 1). In single bolus group, Peak concentration time was 2 min, and the peak concentration reached (5.16±1.02) mg/L, which was significant higher than that in the same dose r SAK infusion group ( P <0.01). In conjunctive therapy group, the peak concentration showed no significant difference from that in the same dose r SAK infusion group ( P >0.05). The plasma levels of r SAK fit in two compartment model as processed by pharmacokinetic computing procedure in each group. Conclusion: The “lytic circle' method is a simple, practical and reliable method to determine the plasma level of r SAK, and the pharmacokinetics o展开更多
A star forest is a forest whose components are stars. The star arboricity of a graph G,denoted by sa( G),is the minimum number of star forests needed to decompose G. Let k be a positive integer. A k-star forest is a...A star forest is a forest whose components are stars. The star arboricity of a graph G,denoted by sa( G),is the minimum number of star forests needed to decompose G. Let k be a positive integer. A k-star forest is a forest whose components are stars of order at most k + 1. The k-star arboricity of a graph G,denoted by sak( G),is the minimum number of k-star forests needed to decompose G. In this paper,it is proved that if any two vertices of degree 3 are nonadjacent in a subcubic graph G then sa2( G) ≤2.For general subcubic graphs G, a polynomial-time algorithm is described to decompose G into three 2-star forests. For a tree T and[Δ k, T)/k]t≤ sak( T) ≤[Δ( T)- 1/K]+1,where Δ( T) is the maximum degree of T.kMoreover,a linear-time algorithm is designed to determine whether sak( T) ≤m for any tree T and any positive integers m and k.展开更多
文摘A new bidihydroflavonoid, thuidinin 1, together with 5 known compounds including one known biflavonoid 3',3"'-binaringenin (2) and four other known natural products pentadecane (3), methyl β-orcinolarboxylate (4), β-sitosterol (5) and daucostenol (6), were isolated from leaves of Thuidium kanedae Sak. Their structures were established on the basis of 1D and 2D spectroscopic analysis. The absolute stereochemistry of compounds 1 and 2 was determined by CD spectra.
文摘Objective: To study the pharmacokinetics of native r SAK in rabbit's femoral artery thrombosis model, the “lytic circle' method was used to determine plasma levels of r SAK. Methods: Thirty New Zealand rabbits were randomly assigned to the control (saline 10 ml, 30 min), r SAK low dose (0.25 mg/kg, 30 min), medial dose (0.50 mg/kg, 30 min), high dose (1.00 mg/kg, 30 min), single bolus (0.50 mg/kg, 2 min) and conjunctive therapy (initiated with heparin 200 U/kg, followed by infusion of r SAK 0.50 mg/kg for 30 min, and subsequently infused heparin 50 U/(kg·h) to endpoint) groups. The right femoral artery thrombosis model in rabbit was made by balloon injury, then the thrombolytic agents were infused through parallel ear vein and the blood samples were collected pre thrombolysis and at different time post thrombolysis to determine the plasma levels of r SAK by “lytic circle' method, the plasma levels of r SAK were processed by pharmacokinetic computing procedure to fit the model. Results: The plasma levels of r SAK and the diameters of lytic circles showed a pretty good linear correlation under the scope of 2.0×10 4 2.0×10 6 U/L, and the averaged recycle rate was (96.05±11.35)%(RSD =±11.82%).All peak concentration time in each infusion group was 30 min, and the peak concentrations positively correlated with the doses administrated in infusion groups(r=0.999 98, P <0.000 1). In single bolus group, Peak concentration time was 2 min, and the peak concentration reached (5.16±1.02) mg/L, which was significant higher than that in the same dose r SAK infusion group ( P <0.01). In conjunctive therapy group, the peak concentration showed no significant difference from that in the same dose r SAK infusion group ( P >0.05). The plasma levels of r SAK fit in two compartment model as processed by pharmacokinetic computing procedure in each group. Conclusion: The “lytic circle' method is a simple, practical and reliable method to determine the plasma level of r SAK, and the pharmacokinetics o
基金National Natural Science Foundation of China(No.10971025)
文摘A star forest is a forest whose components are stars. The star arboricity of a graph G,denoted by sa( G),is the minimum number of star forests needed to decompose G. Let k be a positive integer. A k-star forest is a forest whose components are stars of order at most k + 1. The k-star arboricity of a graph G,denoted by sak( G),is the minimum number of k-star forests needed to decompose G. In this paper,it is proved that if any two vertices of degree 3 are nonadjacent in a subcubic graph G then sa2( G) ≤2.For general subcubic graphs G, a polynomial-time algorithm is described to decompose G into three 2-star forests. For a tree T and[Δ k, T)/k]t≤ sak( T) ≤[Δ( T)- 1/K]+1,where Δ( T) is the maximum degree of T.kMoreover,a linear-time algorithm is designed to determine whether sak( T) ≤m for any tree T and any positive integers m and k.