ABSTRACT
In this work, the studies of thermodynamic mean activity coefficients of KCl in the KCl-SrCl2-H2O ternary system have been made. A cell without liquid junction battery cell, K-ISE|KCl(mA), SrCl2(mB)|Cl-ISE, was used to study the activity coefficients in this mixed system KCl-SrCl2-H2O at 288.15 K by the electromotive force method. The total ionic strengths ranges are 0.0100-1.0000 mol·kg-1 with different ionic strength fractions yb of SrCl2, that is, yb = (0, 0.2, 0.4, 0.6, and 0.8). The results show that the K-ISE and Cl-ISE have a good Nernst response. Accordingly, the electromotive forces of the mixed system were measured by using the ion selective electrode listed above, and the mean activity coefficients are also determined with Nernst equation. Using the activity coefficient data, the mixed ion interaction parameters θK,Sr and ψK,Sr,Cl of Pitzer equations at 288.15 K were fitted by Matlab with linear regression method, respectively. Furthermore, those parameters were applied to calculate the values of the mean activity coefficients of SrCl2. Finally, the osmotic coefficients, water activity, and the excess Gibbs free energy of this system were evaluated by Pitzer's equations.
ABSTRACT
OBJECTIVE: To compare plasma tissue factor (TF) and tissue factor pathway inhibitor (TFPI) levels before, immediately and 24 hours after percutaneous coronary intervention (PCI) in acute myocardial infarction (AMI) patients with or without no-reflow. METHODS: Plasma TF and TFPI in AMI patients underwent PCI were measured by enzyme linked immunoadsorbent (ELISA) before, immediately and 24 hours after PCI. RESULTS: The levels of TF and TFPI of no-reflow patients (n = 17) were significantly higher than those of reflow patients (n = 36) at baseline, immediately and 24 hours after PCI [TF: (275.3 +/- 46.2) ng/L vs. (236.8 +/- 44.3) ng/L, (332.7 +/- 41.3) ng/L vs. (282.3 +/- 38.7) ng/L, (315.5 +/- 47.8) ng/L vs. (248.1 +/- 46.9) ng/L; TFPI: (165.2 +/- 38.4) microg/L vs. (128.5 +/- 18.7) microg/L, (176.3 +/- 36.8) microg/L vs. (135.6 +/- 20.3) microg/L, (149.8 +/- 31.7) microg/L vs. (118.7 +/- 19.2) microg/L; all P < 0.01]. Plasma TF was significantly increased in both groups (all P < 0.01) immediately post PCI and the TF was still higher than that before PCI in no-reflow patients (P < 0.05) and returned to baseline level in reflow patients at 24 hours after PCI (P > 0.05), TFPI levels were similar before and after PCI in both groups (all P > 0.05). CONCLUSION: Plasma tissue factor and tissue factor pathway inhibitor might play important roles in the development of no-reflow during PCI in AMI patients.
