Introduction The degree of earth-resistivity anisotropy was described (MAO, et al, 1995, 1998) as follows: S=|1\nn∑I=1(ρSN\ρEW)I|-1|×103 n=6(1) whereρNS and ρEW are monthly mean values of earth resi...Introduction The degree of earth-resistivity anisotropy was described (MAO, et al, 1995, 1998) as follows: S=|1\nn∑I=1(ρSN\ρEW)I|-1|×103 n=6(1) whereρNS and ρEW are monthly mean values of earth resistivity in the direction of NS and EW, respectively, S is the half-year value. Equation (1) shows that if ρNS=ρEW, then S =0 and the electrical property of medium is isotropic; if ρNS≠ρEW, then S≠0 and the electrical property of medium is anisotropic. When S increases, the anisotropy of electrical property of medium is enhanced. Because the rightside of equation (1) is absolute value and the possibility ofρNS＞ρEW and ρNS＜ρEW can be different at different stations, the increase or decrease of S cannot reflect the relative changes between ρNS and ρEW. FENG, et al (2000) defined S as follows:……展开更多
AIM To filtrate breast cancer resistance protein(BCRP)-mediated resistance agents and investigatethe mechanism,so as to provide valuable datum for optimization clinical chemotherapy scheme to tumor withevaluation mark...AIM To filtrate breast cancer resistance protein(BCRP)-mediated resistance agents and investigatethe mechanism,so as to provide valuable datum for optimization clinical chemotherapy scheme to tumor withevaluation marker of BCRP expression.METHODS MTT assay was used to filtrate BCRP-mediatedresistance agents with PA317/Tet-on/TRE-BCRP cell of different expression levels of BCRP after treated withdifferent concentration anticancer agents.High performance liquid chromatography(HPLC) was applied tomeasure relative dose of intracellular retention resistance agents.Nuclear DNA fluorescence dye,Hochest33258,staining and flow cytometry were adopted to detect apoptotic cells after treated with drugs.RESULTSThere were shown increasing durg-resistance to 5-fluorouracil,methotrexate,doxirubicin,pirarubicin,etoposide and mitoxantrone followed with increasing expression of BCRP on PA317/Tet-on/TRE-BCRPcells(P<0.05,n=3),but shown sensitive to paclitaxel,cisplatin,vincristine,mitomycin and vindesine.Therealso was shown significant negative correlation between the intracellular retention dose of 5-fluorouracil withdifferent expression of BCRP(r=-0.885,P<0.05,n=3).There were shown parallel results ofthat decreasingcellular apoptotic rate with increasing cellular expression of BCRP after treated with 5-fluorouracil byfluorescence dye staining and flow cytometry(P<0.05,n=3),and also shown significate rise of the apoptoticrate of BCRP expression cells after treated with Ko143 (P<0.05,n=3).Every group of cells could be differentextently blocked in phase of G_0/G_1 treated with 5-fluorouracil.CONCLUSION Resistance of 5-fluorouracilcould be especially mediated by conjugated with BCRP and acted as drug exclude-pump substrate.Cellularability resistant to 5-fluorouracil-induced apoptosis could be reinforced by BCRP expression.展开更多
文摘Introduction The degree of earth-resistivity anisotropy was described (MAO, et al, 1995, 1998) as follows: S=|1\nn∑I=1(ρSN\ρEW)I|-1|×103 n=6(1) whereρNS and ρEW are monthly mean values of earth resistivity in the direction of NS and EW, respectively, S is the half-year value. Equation (1) shows that if ρNS=ρEW, then S =0 and the electrical property of medium is isotropic; if ρNS≠ρEW, then S≠0 and the electrical property of medium is anisotropic. When S increases, the anisotropy of electrical property of medium is enhanced. Because the rightside of equation (1) is absolute value and the possibility ofρNS＞ρEW and ρNS＜ρEW can be different at different stations, the increase or decrease of S cannot reflect the relative changes between ρNS and ρEW. FENG, et al (2000) defined S as follows:……
文摘AIM To filtrate breast cancer resistance protein(BCRP)-mediated resistance agents and investigatethe mechanism,so as to provide valuable datum for optimization clinical chemotherapy scheme to tumor withevaluation marker of BCRP expression.METHODS MTT assay was used to filtrate BCRP-mediatedresistance agents with PA317/Tet-on/TRE-BCRP cell of different expression levels of BCRP after treated withdifferent concentration anticancer agents.High performance liquid chromatography(HPLC) was applied tomeasure relative dose of intracellular retention resistance agents.Nuclear DNA fluorescence dye,Hochest33258,staining and flow cytometry were adopted to detect apoptotic cells after treated with drugs.RESULTSThere were shown increasing durg-resistance to 5-fluorouracil,methotrexate,doxirubicin,pirarubicin,etoposide and mitoxantrone followed with increasing expression of BCRP on PA317/Tet-on/TRE-BCRPcells(P<0.05,n=3),but shown sensitive to paclitaxel,cisplatin,vincristine,mitomycin and vindesine.Therealso was shown significant negative correlation between the intracellular retention dose of 5-fluorouracil withdifferent expression of BCRP(r=-0.885,P<0.05,n=3).There were shown parallel results ofthat decreasingcellular apoptotic rate with increasing cellular expression of BCRP after treated with 5-fluorouracil byfluorescence dye staining and flow cytometry(P<0.05,n=3),and also shown significate rise of the apoptoticrate of BCRP expression cells after treated with Ko143 (P<0.05,n=3).Every group of cells could be differentextently blocked in phase of G_0/G_1 treated with 5-fluorouracil.CONCLUSION Resistance of 5-fluorouracilcould be especially mediated by conjugated with BCRP and acted as drug exclude-pump substrate.Cellularability resistant to 5-fluorouracil-induced apoptosis could be reinforced by BCRP expression.
