A functional-link net(FLN) was applied to study the relationships between the structural parameters of metal ions and their Hytrosis Constants pK1. These structural parameters such as radius, electric charge, electron...A functional-link net(FLN) was applied to study the relationships between the structural parameters of metal ions and their Hytrosis Constants pK1. These structural parameters such as radius, electric charge, electronegativity (electricity shouldering) and valence electron structure parameter of the metal ion. The results are satisfactory, and better than that obtained by using linearly statistic methods. Through comparing hytrolysis constants pK1 with hydration-energy ?H, the non-linear characteristic of pK1 have deeply discussed. 19 unknown pK1 of metal ion were predicted with the method.展开更多
Objective To explore the effect of chronic hypoxia on the proliferation and differentiation of LLCPK, cells. Methods: The cells were exposed either to hypoxia (3 % O2) or maintained in normoxia (18 % O2 )followed by t...Objective To explore the effect of chronic hypoxia on the proliferation and differentiation of LLCPK, cells. Methods: The cells were exposed either to hypoxia (3 % O2) or maintained in normoxia (18 % O2 )followed by the assessment of [3H]-thymidine incorporation and cell number as indices of cellular proliferation and sodium - dependent transport of glucose and aminoisobutyric acid (AIB) as indices of differentiation.Protein kinase C (PKC ) was determined with radionuclear technique. Results: Exposure of quiescent culturesto hypoxia for 16 h resulted in a significant increase in [3H]-thymldine followed by a significant increase incell number at 24 h in comparison with respective normoxic controls. Confluent cultures exposed to 72 h ofhypoxia exhibited significant inhibition of α--methyl glucose and AIB uptakes when compared with their respective norrnoxic counterparts. Hypoxia also activated PKC at 4 h followed by a subsequent return to baseline with reactivation at 24 h which remained sustained up to 72 h, suggesting a biphasic acute and sustainedactivation of PKC. Furthermore, the hypoxia--induced alterations in [H]-thymidine incorporation as well asα-methyl glucose and AId transport activities were mitigated by inhibitors of PKC. Conclusion: Chronic hypoxia induces both proliferation and dedifferentiation of LLC-PK, cells mediated, in part, by the sustained activation of PKC.展开更多
文摘A functional-link net(FLN) was applied to study the relationships between the structural parameters of metal ions and their Hytrosis Constants pK1. These structural parameters such as radius, electric charge, electronegativity (electricity shouldering) and valence electron structure parameter of the metal ion. The results are satisfactory, and better than that obtained by using linearly statistic methods. Through comparing hytrolysis constants pK1 with hydration-energy ?H, the non-linear characteristic of pK1 have deeply discussed. 19 unknown pK1 of metal ion were predicted with the method.
文摘Objective To explore the effect of chronic hypoxia on the proliferation and differentiation of LLCPK, cells. Methods: The cells were exposed either to hypoxia (3 % O2) or maintained in normoxia (18 % O2 )followed by the assessment of [3H]-thymidine incorporation and cell number as indices of cellular proliferation and sodium - dependent transport of glucose and aminoisobutyric acid (AIB) as indices of differentiation.Protein kinase C (PKC ) was determined with radionuclear technique. Results: Exposure of quiescent culturesto hypoxia for 16 h resulted in a significant increase in [3H]-thymldine followed by a significant increase incell number at 24 h in comparison with respective normoxic controls. Confluent cultures exposed to 72 h ofhypoxia exhibited significant inhibition of α--methyl glucose and AIB uptakes when compared with their respective norrnoxic counterparts. Hypoxia also activated PKC at 4 h followed by a subsequent return to baseline with reactivation at 24 h which remained sustained up to 72 h, suggesting a biphasic acute and sustainedactivation of PKC. Furthermore, the hypoxia--induced alterations in [H]-thymidine incorporation as well asα-methyl glucose and AId transport activities were mitigated by inhibitors of PKC. Conclusion: Chronic hypoxia induces both proliferation and dedifferentiation of LLC-PK, cells mediated, in part, by the sustained activation of PKC.
