• KSBB Journal
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• v.18 no.4
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• pp.324-328
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• 2003

In a mutagenicity test using the Salmonella typhimurium TA98 and TA100, the Xanthium strumarium L. extracts had not a mutagenicity. The extracts were assayed that antioxidative effect using a colony formation assay. The extracts showed protective effects against the cytotoxicity of H$_2$O$_2$ and increased the immunity induced by TNF and IL-1${\beta}$. The modulating effect of Xanthium strumarium L. extract on the induction of carcinogenesis by N-methyl-N'-nitro-N-nitrosoguanidin (MNNG), was investigated in Wistar rats. The GSH content was found to be reduced by MNNG treatment, but increased on adding extract. In addition the Xanthium strumarium L. extract increased p53 expression versus MNNG alone.

• Biomolecules & Therapeutics
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• v.3 no.3
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• pp.182-187
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• 1995

The clastogenecity and mutagenicity of antifungal 6-[(N-halophenyl)amino]-7-chloro-5, 8-quinolinedione (RCK 3, 7, 13, 14, and 15) had been evaluated. Salmonella typhimurium reversion assay (Ames test) was used to test the mutagenicity of RCKs. RCK14 was mutagenic in S. typhimurium(TA98 and TA100) with and without rat liver microsomal activation. Whereas RCK3, 7, 13 and 15 were negative in Ames test with Salmonella typhimurium(TA98 and TA100), The clastogenecity was tested on the RCKs with in vivo mouse micronucleus assay. All of RCKs tested did not show any clastogenic effect in mouse peripheral blood. Thus RCKs were not supposed to cause any chromosomal damage termed micronuclei. These results indicate that RCK 3, 7, 13 and 15 have no genotoxic potential under these experimental condition.

• Proceedings of the Korean Magnestics Society Conference
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• 1999.10a
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• pp.42-43
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• 1999

• Journal of Powder Materials
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• v.15 no.6
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• pp.489-495
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• 2008

Colored tantalum oxy-nitride (TaON) and tantalum nitride ($Ta_{3}N_{5}$) were synthesized by ammonolysis. Oxygen deficient tantalum oxides ($TaO_{1.7}$) were produced by a titration process, using a tantalum chloride ($TaCl_5$) precursor. The stirring speed and the amount of $NH_{4}OH$ were important factors for controling the crystallinity of tantalum oxides. The high crystallinity of tantalum oxides improved the degree of nitridation which was related to the color value. Synthesized powders were characterized by XRD, SEM, TEM and Colorimeter.

• Journal of the Korean Chemical Society
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• v.33 no.2
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• pp.149-155
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• 1989

1H-nmr chemical shifts and lineshapes of amino-protons of thioacetamide in n-alcohols were determined. The chemical shifts are discussed by the Reichardt's solvent polarity parameter, $E_T(30)$. The following relationship between ${delta}_{obs}\;and\;E_T(30)$ was obtained, ${\delta}_{obs}=a{\cdot}E_T(30)＋b{\cdot}(E_T(30))_2$ where a is a characteristic constant for the protons of thioacetamide in n-alcohol solutions and b is a constant for the solute(TA)-solvent (n-alcohols) interactions. The barrier of the hindered rotation about the N-C(S) bond in TA was obtained by analysis of the lineshape of the amino-protons in TA. The behavior of the hindered rotation as well as chemical shifts of the amino-protons in TA has been found to be closely related to the $E_T(30)$ of n-alcohols.

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.05a
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• pp.133-133
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• 2002

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.05a
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• pp.123-123
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• 2002

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.05a
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• pp.117-117
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• 1998

• Proceedings of the Materials Research Society of Korea Conference
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• 1999.05a
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• pp.98-98
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• 1999

• Proceedings of the Materials Research Society of Korea Conference
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• 1997.05a
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• pp.19-19
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• 1997