• The Journal of the Petrological Society of Korea
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• v.14 no.4 s.42
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• pp.226-236
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• 2005

Using the concept of granite suite/supersuite we hierarchically divided the Triassic granites in South Korea which have spatio-temporally close relationships each other. Among the Triassic granites in the Okcheon belt (western Yeongnam massif), the Baegrok granite and the Jeomchon granite can be grouped into one suite, the Baegrok suite, whereas the Cheongsan granite into the Cheongsan suite. These two suites can be grouped again into a larger supersuite, the Baegrok supersuite, on the basis of the similarity in the source rocks and the contrasts in the petrographic and geochemical characteristics. Three Triassic granites in the Gyeongsang basin - the Yeongdeok granite, the Yeonghae granite, and the Cheongsong granite - can be grouped into the Yeongdeok suite, Yeonghae suite and Cheongsong suite, respectively. These three suites can be grouped again into a larger supersuite, the Yeongdeok supersuite, on the basis of the similarity in the source rocks and the contrasts in the petrographic and geochemical characteristics. Nd-Sr isotopic signatures for the Baegrok supersuite are quite distinct from those for the Yeongdeok supersuite, indicating that the source materials of each granitic magma were not identical. The source rocks for the Baegrok supersuite are thought to be a mixture of two crustal components of the Yeongnam massif, whereas those for the Yeongdeok supersuite to be a mixture of the depleted mantle with the crustal components of the Yeongnam massif. The fact that the two contemporaneous granite supersuites were derived from the different sources can be explained by the difference of the tectonic environments where the granitic magmas were produced.

• The Korean Journal of Zoology
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• v.27 no.3
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• pp.151-164
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• 1984

In order to investigate the mechanism of myoblast fusion during muscle differentiation in culture, the effect of muscle-conditioned medium on the fusion was studied and possible release from cultured myoblast cells of proteins which may be responsible for the promotion of myoblast fusion was analyzed. The muscle-conditioned medium showed a marked fusion-promoting activity in a dose-dependent fashion. THis fusion-promoting activity of the muscle-conditioned medium appeared to be due to the accumulation of at least two proteins which were released from the myoblast into the culture medium. These released proteins were analyzed by electrophoresis and autoradiography and found to have molecular weights of 45,000 and 65,000.

• The Korean Journal of Zoology
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• v.38 no.4
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• pp.483-489
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• 1995

Retinoic acid was found to block membrane fusion of chick embryonic myoblasts in culture. This effed was dosedependent and could he reversed upon removal of the agent from the culture medium. Furthermore, the retinoic acid-mediated inhibition of membrane fusion was observed with the fusion competent cells but not with the cells that had already been committed for fusion, indicating that the effect of RA is differentiation stage-specific. However, retinoic acid showed little or no effect on the ability of the cells to form bipolar shape and to align along their axes. Neither the cell proliferation nor accumulation of muscle specific proteins, such as creatine kinase and tropomyosin, was impaired significantly. On the other hand, retinoic acid blocked the differentiation time~ependent loss of fibronectin, whose process is prerequisite for myoblast fusion. These results suggest that retinoic add acts as a specific inhibitor of membrane fusion by preventing the loss of fibronectin from the differentiating myoblasts.

• The Korean Journal of Zoology
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• v.27 no.2
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• pp.73-84
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• 1984

In order to investigate the effect of neurotransmitter on myoblast differentiation in vitro, the effects of dopamine and epinephrine on myoblast fusion and on the intracellular cAMP level in cultured myoblasts were examined. Dopamine $(3\\times10^{-5}M)$ and epinephrine $(3\\times10^{-5}M)$, when added at 34 hr after cell plating, markedly inhibited myoblast fusion, and dopamine was more potent than epinephrine. Both dopamine and epinephrine had no effect on intracellular cAMP level. At the same time, exogeneous dbcAMP, $PGE_1$, and aspirin were used to examine whether cAMP is involved in myoblast differentiation. dbcAMP $(1\\times10^{-4}M)$ inhibited myoblast fusion, whereas $PGE_1 (3\\times10^{-6}M)$ had no inhibitory effect, rather enhancing myoblast fusion. Aspirin, an inhibitor of PG synthetase, was shown to inhibit myoblast fusion. Possible mechanism by which dopamine or epinephrine at a specific concentration used inhibits myoblast fusion is discussed.

• 월간산업보건
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• s.326
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• pp.31-35
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• 2015

• 월간산업보건
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• s.289
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• pp.56-57
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• 2012

• 월간산업보건
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• s.336
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• pp.26-29
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• 2016

• The Journal of the Petrological Society of Korea
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• v.17 no.4
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• pp.222-230
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• 2008

Intruding ages for the Jurassic(${\sim}Triassic$) granites in South Korea can be reestablished as $210{\sim}170\;Ma$ and $180{\sim}160\;Ma$ according to the tectonic provinces of magma emplacement. Most Jurassic granites in the Gyeonggi massif have the intrusion ages of $180{\sim}160\;Ma$, indicative of middle Jurassic igneous activity. On the other hand the intrusion ages ($210{\sim}170\;Ma$) for the Jurassic granites in the Yeongnam massif represent late Triassic to middle Jurassic igneous activity. Using the concept of granite suite/supersuite, the Jurassic granites in South Korea can be hierarchically divided into two supersuites and two suites. Huge batholith of NE-SW direction in the Gyeonggi massif could be designated to be 'Gyeonggi Supersuite', which was originated from the mixture of igneous protolith and more evoloved crustal materials and formed in the post-orogenic environment after collision of the north China and south China blocks. There are one supersuite and two suites in the Yeongnam massif 'Yeongnam Supersuite' could be designated from the NE-SW trend batholith in the massif. This supersuite was originated from the mixture of igneous protolith and evolved crustal materials. Granitic rocks between Andong and Girncheon areas could be defined as 'Andong Suite'. This suite was originated from the mixture of depleted mantle and igneous protolith. The Daegang and Hamchang granties could be designated as 'Daegang Suite'. This suite was formed in the anorogenic environment which was different from the orogenic environment of the other supersuite/suite in the Yeongnam massif.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2002.11a
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• pp.288-292
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• 2002

• Korean Journal of Food Science and Technology
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• v.6 no.2
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• pp.79-85
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• 1974

To obtain further information concerning the nature myofibrillar proteins in a food system, an investigation has been conducted to compare the change in the biochemical property of the myofibril with the changes in the morphological structure of the myofibril. When myofibrils were prepared with 0.16 M KCl-0.04 M Tris-HCl, the band pattern was clear and distinct. There was a uniform thickening of A-band, a sharp appearence of Z-lines and a wide I-band. The band pattern of myofibrils was changed as the composition of extraction solution was changed. Also the ATPase activity of myofibril changed as the length of sarcomere changed. When myofibrils were treated with a low concentration of trypsin, myofibrils turned in the contracted state. With the progress of prolonged trypsin treatment, most of myofibrils exhibited a pattern of alternating light and dark bands, supercontracted pattern. Although myofibrils exhibited a supercontracted band pattern, the ATPase activity of myofibril continued to increase with the progress of trypsin treatment. An assumption was made that tropomyosin may be located in Z-line and that troponin-tropomyosin complex can inhibit the ATPase activity of myofibrils through the structural alternation of myofibril.