• Communications of the Korean Mathematical Society
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• v.20 no.3
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• pp.457-466
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• 2005

We study in this note rings whose prime radicals are completely prime. We obtain equivalent conditions to the complete 2-primal-ness and observe properties of completely 2-primal rings, finding examples and counterexamples to the situations that occur naturally in the process.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.20-21
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• 2001

Free radicals and oxidative stress playa crucial role in the pathophysiology of a broad spectrum of cardiovascular diseases including congestive heart failure, valvular heart disease, cardiomyopathy, hypertrophy, atherosclerosis and ischemic heart disease. We have demonstrated that IH 636 proanthocyanidin extract (GSPE) provides excellent protection against free radicals in both in vitro and in vivo models, and exhibits significantly better efficacy as compared to vitamins C, E and $\beta$-carotene.(omitted)

• Kyungpook Mathematical Journal
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• v.48 no.4
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• pp.545-551
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• 2008

Necessary and sufficient conditions for a radical class of rings to satisfy the polynomial equation $\rho$(R[x]) = ($\rho$(R))[x] have been investigated. The interrelationsh of polynomial equation, Amitsur property and polynomial extensibility is given. It has been shown that complete analogy of R.E. Propes result for radicals of matrix rings is not possible for polynomial rings.

• Journal of the Korean Chemical Society
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• v.10 no.1
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• pp.43-45
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• 1966

The rate of exchange of I atom between alkyl iodides(ethyl or methyl iodide) and $I_2$ in n-hexane have been determined using $II^{131}$. It is found that the escape of $CH_3$ radicals from a solvent cage is faster than $C_2H_5$ radicals and that photolysis of $C_2H_5I$ is almost identical to that in the case of $CH_3I$.

• Bulletin of the Korean Chemical Society
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• v.29 no.12
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• pp.2341-2345
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• 2008

• Bulletin of the Korean Chemical Society
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• v.14 no.4
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• pp.465-468
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• 1993

Four compounds containing two 2,2,6,6-tetramethylpiperidin-1-yloxyl radicals were synthesized. They are all chemically bonded with squaric moieties. The diradical compounds show fundamentally the paramagnetic behaviors satisfying the theoretical magnetic susceptibility according to Curie's law. A diradical compound of salf-form 4 however shows a relatively strong antiferromagnetic interaction in comparison with other reported organic radicals. The antiferromagnetic interaction of diradical 4 approximates a value of J/k= -50 K by the theoretical analysis of its temperature dependence.

• Bulletin of the Korean Chemical Society
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• v.6 no.4
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• pp.206-209
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• 1985

The gas phase reactions of the photochemically generated t-butoxy radicals with phosphine ($PH_3$) were studied in the temperature range of $35-80^{\circ}C.$ We found the significant differences between high temperature thermal reactions and low temperature photo reactions. In comparison with the reactions of t-butoxy radicals with other hydrogen donors, some possible mechanistic suggestions were made for the explanation of the results.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.89-89
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• 2002

It is well known that oxygen radicals induce neuronal cell damage by initiation of lipid peroxidation chain reaction. Recent work has been also demonstrated that enzymatically generated free radicals cause the release of glutamate and aspartate from cultured rat hippocampal slices.(omitted)

• Tuberculosis and Respiratory Diseases
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• v.42 no.6
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• pp.862-870
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• 1995

Background: Oxygen free radicals have generally been considered as cytotoxic agents. On the other hand, recent results suggest that small nontoxic amounts of these radicals may act a role in intracellular signal transduction pathway and many efforts to reveal the role of these radicals as secondary messengers have been made. It is evident that the oxygen radicals are released by various cell types in response to extracellular stimuli including LPS, TNF, IL-1 and phorbol esters, all of which translocate the transcription factor $NF{\kappa}B$ from cytoplasm to nucleus by releasing an inhibitory protein subunit, $I{\kappa}B$. Activation of $NF{\kappa}B$ is mimicked by exposure to mild oxidant stress, and inhibited by agents that remove oxygen radicals. It means the cytoplasmic form of the inducible tanscription factor $NF{\kappa}B$ might provide a physiologically important target for oxygen radicals. At the same time, it is well known that LPS induces the release of oxygen radicals in neutrophil with the activation of $NF{\kappa}B$. From above facts, we can assume the expression of IL-8 and IL-$1{\beta}$ gene by LPS stimulation may occur through the activation of $NF{\kappa}B$, which is mediated through the release of $I{\kappa}B$ by increasing amounts of oxygen radicals. But definitive evidence is lacking about the role of oxygen free radicals in the expression of IL-8 and IL-$1{\beta}$ gene in mononuclear phagocytic cells. We conducted a study to determine whether oxygen radicals act a role in the expression of IL-8 and IL-$1{\beta}$ gene in mononuclear phagocytic cells. Method: Human peripheral blood monocytes were isolated from healthy volunteers. Time and dose relationship of $H_2O_2$-induced IL-8 and IL-$1{\beta}$ mRNA expression was observed by Northern blot analysis. To evaluate the role of oxygen radicals in the expression of IL-8 and IL-$1{\beta}$ mRNA by LPS stimulation, pretreatment of various antioxiants including PDTC, TMTU, NAC, ME, Desferrioxamine were done and Northern blot analysis for IL-8 and IL-$1{\beta}$ mRNA was performed. Results: In PBMC, dose and time dependent expression of IL-8 and IL-$1{\beta}$ mRNA by exogenous $H_2O_2$ was not observed. But various antioxidants suppressed the expression of LPS-induced IL-8 and IL-$1{\beta}$ mRNA expression of PBMC and the suppressive activity was most prominant when the pretreatment was done with TMTU. Conclusion: Oxygen free radical may have some role in the expression of IL-8 and IL-$1{\beta}$ mRNA of PBMC but that radical might not be $H_2O_2$.

• Kyungpook Mathematical Journal
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• v.34 no.2
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• pp.227-228
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• 1994