• Environmental Analysis Health and Toxicology
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• v.16 no.1
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• pp.29-34
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• 2001

The estrogenic potency of di -2-ethylhexyl phthalate (DEHP) using reverse transcriptase-PCR respouse of liver vitellogenin mRNA in male African clawed frog (Xenopus laevis) was studied. Male frogs were injected with DEHP at dose of 300$\mu\textrm{g}$/kg and 300 mg/kg body weight through the dorsal lymph sac. After 4 days, using suitable pair of RT-PCR primers, vitellogenin mRNA induction in the liver was measured and DEHP showed vitellogenin mRNA induction in only the group treated with 300 mg/kg. Any significant histological abnormalities by the exposure of DEHP was not shown in both testis and liver.

• The Korean Journal of Ecology
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• v.23 no.4
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• pp.309-313
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• 2000

Since specific types and physical characteristics of anuran calls can represent reproductive qualities of a calling male, anuran calls have been studied in context of mate choice. We in here report call types of Rana dybowskii and their variations from two different recording sites. Calls of R. dybowskii are classified to three types based on their physical characteristics and behavioral observations; 'A-call'functions to advertise locations of a calling male and to attract potential mates. A territorial male emits 'B-call'only during male-male interaction. 'C -call'is released when a male frog was clasped by another male. The A-call from two recording sites, Miwon and Wonju, shows high variations in their call characteristics.

• The Korean Journal of Zoology
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• v.17 no.4
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• pp.177-184
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• 1974

The cobalt capture method of Gomori's modified technique(Gomori, 1952) was employed to study the histochemistry of the developing frog kidney. Alkaline phosphatase activity was observed in association with the brush borders of pronephros and mesonephros. By the stage of transition from larva to tadpole alkaline phosphatase activity was gradually increased in the brush border of pronephros, and as the pronephros begun to degenerate the enzyme activity was decreased and disappeared. By the time of maximum development of the pronephros the mesonephros began to develop and alkaline phosphatase activity of the mesonephric tubules showed highly positive throughout the stage of metamorphosis. No activity was observed in association with the collecting tubules and ductal elements.

• Journal of Korea Water Resources Association
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• v.35 no.4 s.129
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• pp.443-452
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• 2002

The propagation of the 1983 Central East Sea Tsunami recorded as the most devastating tsunami during last decades across the East Sea is numerically simulated in this study h numerical model based on the shallow~water equations is employed. The physical dispersion is somewhat replaced by the numerical dispersion resulting from the leap-frog scheme. Traveling times of leading tsunamis are estimated and wane rays are calulated based on the Munk and Arthur(1952).

• YAKHAK HOEJI
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• v.7 no.4
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• pp.86-91
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• 1963

Crystal A and B were isolated from L. pseudo-leave Nakai and their pharmacological action was observed. Crystal A, in dose of 5 * $10^{-4}$ - 5 * $10^{-5}g/ml$, stimulated excised frog heat but at 2.5 * $10^{-6}$ - 0.5 * $10^{-5}g/ml$ of crystal B, depressant effect was observed. Mild stimulation of rhythmicity of exercised rabbit intestine was produced by 1 * $10^{-4}$ g/ml of crystal A and 2 * $10^{-4}g/ml$ of crystal B. Marked depression of tone was produced by 2 * $10^{-4}g/ml$ of crystal A, antagonizing by pilocarpine. Crystal B(4 * $10^{-4}gm/l)produced$ mild stimulation, followed by depression of tone. No curare-like action on excised frog abdominal muscle was elicited with both substances.

• Journal of Korean language education
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• v.28 no.4
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• pp.245-271
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• 2017

This study aimed at investigating the lexical diversity in the "Frog Story" narratives of Korean-Chinese bilingual children. Six bilingual speakers of Korean children- four boys and two girls- were audio recorded as they produced narratives based on pictures from the Mercer Mayer book "Frog, where are you?" The order of narration was counterbalanced. The vocabularies from narratives were analyzed by type, token, TTR (type-token Ratio) and D value using the CLAN (Computerized Language Analysis) program. The findings showed that the pattern of lexical diversity in Korean is similar with the Chinese, but the TTR and D value of Chinese still remain low in comparison with those of Korean. In addition, Korean language seems to have significant influence on Chinese in the language usage pattern and vice versa.

• Journal of Ecology and Environment
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• v.46 no.4
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• pp.276-281
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• 2022

Ranaviruses are a primary cause of amphibian extinctions. More consistent ranavirus-infection reports and genetic characterizations of identified viruses are urgently needed, particularly from Asian countries. The objectives of this study were to obtain the partial major capsid protein (MCP) gene sequences (506 bp) of the ranavirus responsible for infecting frogs in South Korea, as our previous research had confirmed using qPCR, and to evaluate their genetic relationships with other previously reported ranavirus sequences. Three different ranavirus MCP sequences were obtained from Pelophylax nigromaculatus and Lithobates catesbeianus. All six different types of MCP sequence from the ranavirus identified in South Korea to date belonged to the Frog virus 3 (FV3)-like virus group in the genus Ranavirus. To better understand the origin and spread of ranaviruses in South Korea, further infection reports and full genome analyses of the identified ranaviruses are needed.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2007.10a
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• pp.82-86
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• 2007

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2010.04a
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• pp.150-154
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• 2010

• Proceedings of the Optical Society of Korea Conference
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• 2004.07a
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• pp.118-119
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• 2004