• Journal of Chest Surgery
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• v.29 no.4
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• pp.365-372
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• 1996

In an attempt to evaluate the effect of St. Thomas' hospital cardioplegic solution (STH) I and II on the cultured rat myocardial cells, beating rate, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (Irtrazolium MTT) and lactate dehydrogenase activity were investigated, and also light and electron microscopic studies were carried out. After rat myocardial cells were cultured for 72 hours, cells were treated with STH I or with STH H solution for 30 and 120 min. and thereafter myocardial cells were cultured in control medium for 24 hours. The results obtained were as follows : 1. Beating rate was 154 times per min. in control group, 141 times per min. in STH I solution(for 2. 120 min.)-treated group and 145 times in STH ll solution (for 120 min.)-treated group. MTT absorbances by MTT assay were 102% in STH I solution (for 120 min.)-treated group and 93% in STH ll solution (for 120 min.)-treated group compared with control group. 3. The amount of lactate dehydrogenase released into the medium were 123% in STH I solution (for 120 min.)-treated group and 109% in STH H solution (for 120 min.)-treated group compared with control group. 4. In the light microscopy examination, myocardial cells showed no differences between experimental and control groups in their number and shape. 5. In the electron microscopy examination, myocardial cells treated with STH I solution showed fewer destroyed mitochondria compared to STH ll solution-treated group. These results suggest that both 51. Thomas'cardioplegic solution STH 1 and STH H have no cytotoxicity on cultured rat myocardial cells, but STH H solution has more protective effect on myocardial cells compared to STH I solution.

• Structural Engineering and Mechanics
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• v.6 no.5
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• pp.529-542
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• 1998

Generalised plane strain solution is presented for simply supported, angle-ply laminated hybrid plate under cylindrical bending. The arbitrary constants in the general solution of the governing differential equations are obtained from the boundary and interface conditions. The response of hybrid plates to sinusoidal loads is obtained to illustrate the effect of the thickness parameter and the ply-angle. The classical lamination theory and the first order shear deformation theory are also assessed.

• Journal of Advanced Marine Engineering and Technology
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• v.21 no.5
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• pp.535-541
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• 1997

The effect of concentration of each solution( HCI, $H_2SO_4$ and $HNO_3$), scan rate and polished surface condition on the corrosion of AISI 304 Stainless Steel were investigated, utilizing the Method ASTM G5 - 87. It can be concluded that: 1) For the same concentration(i.e. 1N) of each solution the corrosion rate is the highest in HCI and lowest in $HNO_3$. Also, the difference of values of $i_{cirt}$ generated for each solution is significant. 2) As the concentration of the solution $H_2SO_4$ is increased (O.5N, 1N, 2N) the values of $E_{cor}$ $i_{crit}$ and $i_{p}$ are increased. 3) In case of existence of SCN ion of O.OlN, the values of iCTIt and ip generated are approximately 100 times and 1.4 times higher respectively, than in the case of non - existence of $SCN^{-}$. However the existence of $SCN^{-}$ doesn't affect the value of $E_{cor}$ and $E_{p}$. 4) The values of $i_{crit}$ and $i_{p}$ are increased due to the increase of scan rate. But the values of $E_{cor}$ and $E_{p}$ do not depend on the scan rate. 5) The $i_{p}$ value depends greatly on oxygen in the solution, but the changes in values of $E_{cor}$ $i_{crit}$ and $E_{b}$ due to the oxygen are insignificant. 6) If a component is polished using #400, #600 and #800 wet polish paper, the effect of surface condition on variations of values of $i_{crit}$ and $i_{p}$ is slightly significant.

• Journal of the Korean Mathematical Society
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• v.55 no.2
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• pp.327-342
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• 2018

In this paper, a homotopy continuation method for obtaining the unique Hermitian positive definite solution of the nonlinear matrix equation $X-{\sum_{i=1}^{m}}A^{\ast}_iX^{-p_i}A_i=I$ with $p_i$ > 1 is proposed, which does not depend on a good initial approximation to the solution of matrix equation.

• Journal of Acupuncture Research
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• v.27 no.4
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• pp.223-231
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• 2010

Objectives : The objective of this study is to study the effects of Euonymi Lignum Suberatatum pharmacopuncture solution on NO and IL-6 production in macrophage. Methods : At first, the RAW 264.7 macrophage was subclutured. In order to evaluate cytotoxicity, MTT assay performed. Then, the cell was induced by LPS, INF-$\gamma$ and Experimental groups were divided into five(Normal, Control, Euonymi Lignum Suberatatum 100, 200, $300{\mu}g/m{\ell}$). Then Euonymi Lignum Suberatatum pharmacopuncture solution was put into cell. We measured IL-6, iNOS, NO. Results : The cytotoxic effect of Euonymi Lignum Suberatatum pharmacopuncture solution in RAW 264.7 macrophage was not appeared. $300{\mu}g/m\ell$ Euonymi Lignum Suberatatum pharmacopuncture solution inhibited IL-6 production in LPS, INF-$\gamma$-stimulated RAW 264.7 macrophages significantly. Euonymi Lignum Suberatatum pharmacopuncture solution inhibited iNOS revelation in LPS, INF-$\gamma$-stimulated RAW 264.7 macrophages. All group of Euonymi Lignum Suberatatum pharmacopuncture solution inhibited NO production in LPS, INF-$\gamma$-stimulated RAW 264.7 macrophages significantly. Conclusions : Our study demonstrated that Euonymi Lignum Suberatatum pharmacopuncture solution had an inhibition effect on NO production, iNOS revelation, IL-6 production. So Euonymi Lignum Suberatatum pharmaco puncture solution may have an Anti-inflammation effect.

• Journal of Chest Surgery
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• v.21 no.6
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• pp.979-983
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• 1988

Calcium channel blockers may prevent myocardial injury during cardioplegia and reperfusion. This study was done to evaluate the effects of diltiazem cardioplegia on myocardial protection during ischemic arrest and recovery of myocardial function after reperfusion. Four formulations of crystalloid cardioplegic solutions, GIK solution[group I, n=12], diltiazem[lug/ml GIK] in GIK solution[group II, n=7], ],diltiazem[2ug/ml GIK] in GIK solution[group III, n=6] and diltiazem[4ug/ml GIK] in GIK solution[group IV, n=6] were compared in isolated working rat heart subjected to a long period [2 hours] of hypothermic arrest with multi-dose infusion. Diltiazem cardioplegia[group II, III and IV]was found to be superior in nearly all aspects. Diltiazem cardioplegia showed faster recovery of regular rhythm and lower incidence of ventricular fibrillation than group I did. In comparing mechanical function in all experimental hearts, the mean postischemic recoveries of aortic flow, cardiac output, peak aortic pressure, stroke volume and stroke work[expressed as a percentage of its preischemic control] were significantly greater in group II, III and IV[diltiazem cardioplegia] than in group I. The infused amount of cardioplegic solution was more increased by the addition of diltiazem to GI K solution. [p < 0.01] Creatine kinase leakage tended to be lower in hearts receiving diltiazem cardioplegia, especially in group III and IV[p<0.05] than in those receiving GIK solution only[group I]. Diltiazem cardioplegia results in the increased flow of cardioplegic solution and the decreased ischemic injury of myocardium during ischemic arrest and the improved recovery of myocardial function after reperfusion, and a dose-response relation must be established before clinical use.

• Journal of applied mathematics & informatics
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• v.30 no.3_4
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• pp.655-663
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• 2012

Based on the elegant properties of the spectral norm and Thompson metric, we firstly give two perturbation estimates for the positive definite solution of the nonlinear matrix equation $$X-\sum^m_{i=1}A^{\ast}_iX^{\delta_i}A_i=Q(0<|{\delta}_i|<1)$$ which arises in an optimal interpolation problem.

• Communications of the Korean Mathematical Society
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• v.23 no.2
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• pp.191-199
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• 2008

We investigate the relation between the vector variable bi-additive functional equation $f(\sum\limits^n_{i=1} xi,\;\sum\limits^n_{i=1} yj)={\sum\limits^n_{i=1}\sum\limits^n_ {j=1}f(x_i,y_j)$ and the multi-variable quadratic functional equation $$g(\sum\limits^n_{i=1}xi)\;+\;\sum\limits_{1{\leq}i<j{\leq}n}\;g(x_i-x_j)=n\sum\limits^n_{i=1}\;g(x_i)$$. Furthermore, we find out the general solution of the above two functional equations.

• Coupled systems mechanics
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• v.9 no.1
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• pp.77-89
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• 2020

This study is dedicated to the dynamic elasticity problem for a semi-strip. The semi-strip is loaded by the dynamic load at the center of its short edge. The conditions of fixing are given on the lateral sides of the semi-strip. The initial problem is reduced to one-dimensional problem with the help of Laplace's and Fourier's integral transforms. The one-dimensional boundary problem is formulated as the vector boundary problem in the transform's domain. Its solution is constructed as the superposition of the general solution for the homogeneous vector equation and the partial solution for the inhomogeneous vector equation. The matrix differential calculation is used for the deriving of the general solution. The partial solution is constructed with the help of Green's matrix-function, which is searched as the bilinear expansion. The case of steady-state oscillations is considered. The problem is reduced to the solving of the singular integral equation. The orthogonalization method is applied for the calculations. The stress state of the semi-strip is investigated for the different values of the frequency.

• Analytical Science and Technology
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• v.11 no.4
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• pp.248-253
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• 1998

The adsorption and separation behaviors of alkali, alkaline earth and transition metal ions using a poly-dibenzo-18-crown-6 were investigated in aqueous solution. The adsorption degree(E) and distribution ratio(D) of alkali, alkaline earth metal ions were Li(I)$t_R$) of metal ions were affected by the adsorption degree(E) and distribution ratio(D). This results showed good separation efficiency of K(I), Sr(II), Ag(I) and Pb(II) from the mixed metal solution.