• The Korean Journal of Zoology
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• v.37 no.3
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• pp.311-317
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• 1994

Seasonal variations of GnRH were investigated by immunohlstochemicsl technique in three species of frog, Rona niEromaculutu, R. dvbowskii 8nd R. mgosa with different ovulation period in order to examine the relationship between GnRH expression and reproductive function. In all three species of frog, the intensity of GnRH immunoreactivitv and the number of GnRH neurons in the brawn were relatively high in frogs at the pre-ovulation period and markedly increased at the ovulation period. Those were then decreased after ovulation and further lowered during early hibernation period. These results indicate that GnRH experssion is closely related to specific phases of annual reproductive cycle in frog.

• YAKHAK HOEJI
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• v.35 no.5
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• pp.432-437
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• 1991

A mixture of 20(R)- and 20(S)-ginsenoside Rg$_{3}$ was obtained under mild acidic hydrolysis from protopanaxadiol saponins, ginsenosides Rb$_{1}$, Rb$_{2}$, Rc and Rd. The product was acetylated to give the peracetates, which were further converted into 20(R)-ginsenoside Rg$_{3}$, 20(S)-ginsenoside Rg$_{3}$, 20(R)-ginsenoside Rh$_{2}$ and 20(S)-ginsenoside Rh$_{2}$ by the direct alkaline treatment depending upon two kinds of temperature conditions respectively. The structure and physicochemical properties of a prosapogenin, 20(R)-ginsenoside Rh$_{2}$, were investigated.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.217.1-217.1
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• 2012

현존하는 저궤도위성의 S-Band 관제채널은 대부분 RH 또는 LH 편파를 사용한다. 그러나 다목적실용위성 3호와 같이 RH와 LH 편파를 동시에 사용하는 위성의 경우 위성추적을 위해 사용되어지는 지상안테나는 RH와 LH 편파를 동시에 수신하여야할 뿐만 아니라 편파변경시점에 따라 송신출력의 편파가 변경되어야하기 때문에 지상에서 위성으로 명령을 전송할 수 있는 송신가능시간(Command Window)에 영향을 미친다. 이러한 저궤도위성의 RH와 LH 편파의 신호세기는 위성체의 자세 및 운영방법에 따라 결정되어지기 때문에 다양한 형태의 편파수신경향성을 나타낸다. 따라서 이러한 영향을 최소화하기 위하여 지상안테나는 RH 및 LH 편파에 대하여 자동추적기능을 수행하여 위성을 추적하게 된다. 지상안테나의 자동추적기능은 수신되는 신호세기를 순간적으로 비교하여 가장 큰 세기의 신호가 수신될 수 있도록 제어하는 기술로서 수신신호의 형태에 따라 영향을 받으며 이 때 발생하는 오차는 위성추적에 지대한 영향을 미친다. 또한 편파가 변경되는 시점에서는 자동추적오차가 증가하게 되는 경향을 나타나게 된다. 따라서 본 논문에서는 다양한 형태로 동시 수신되는 RH 및 LH 편파의 자동추적오차를 분석하여 송신가능시간(Command Window) 및 수신신호에 어느 정도 영향을 미치는지에 대하여 분석하였으며 본 영향을 최소화할 수 있는 방법에 대하여 기술하였다.

• YAKHAK HOEJI
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• v.39 no.1
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• pp.85-93
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• 1995

Acidic and alkaline hydrolysis of diol-type ginseng saponins produced a new glycoside, (20E)-ginsenoside Rh$_{3}$, and its stereoisomer (20Z)-, which were further subjected to alkaline by drolysis to give their aglycones, (20E)- and (20Z)-3$\beta$, 12$\beta$-dihydroxy-dammar-20(22),24-diene. The ratio of stereoisomeric mixtures was estimated to be ca. 5:1 from intensities of the peaks in $^{1}$H- and $^{13}$C-NMR spectra. The $^{1}$H- and $^{13}$C-NMR signals of ginsenoside Rh$_{3}$, which have remained unclarified, were completely assigned by the extensive application of modern NMR techniques.

• Journal of Ginseng Research
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• v.19 no.2
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• pp.114-116
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• 1995

Panax ginseng ginsenosides were examined for their affects on the DNA synthesis. The DNA 1 synthesis was measured by the thymidine incorporation into NIH3T3 cells. The ginsenoside, panaxytriol, $Rh_1$ and $Rh_2$ showed reduced [$^{3}H$]-thymidine incorporation. However, other ginsenosides of $Rh_1$, $Rh_2$ and $Rh_3$ did not inhibit DNA synthesis. Among the various ginsenosides, ginsenoside $Rh_2$ was found to be the most inhibitory on DNA synthesis. We suggest $Rh_2$ as one of the potential choice of antiproliferative drugs.

• Development and Reproduction
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• v.13 no.4
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• pp.353-362
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• 2009

GnRH and its receptor are known to express locally in the ovary and to regulate the ovarian function by affecting on granulosa and lutein cells. It has been reported that GnRH directly causes apoptosis in the granulosa and lutein cells of the ovary. However, whether the apoptosis of the cells by GnRH is recovered by FSH as an anti-apoptotic factor is not yet known. In this study, we evaluated the apoptosis and the production of progesterone $(P_4)$ and estradiol $(E_2)$ after treatment with 5, 50, and 100 ng/$m\ell$ GnRH and 1 IU/ml FSH in the granulosa-lutein cells that are obtained during oocyte-retrieval for IVF-ET. Results of DNA fragment analysis and TUNEL assay demonstrated that DNA fragmentation and the rate of apoptotic cells were increased in a dose-dependent manner showing a significant increase in the cells treated with 100 ng/$m\ell$ GnRH. In addition, we found that FSH suppresses the apoptosis of the cells induced by GnRH. In the results of chemiluminescence assay for $P_4$ and $E_2$, $P_4$ production was decreased by GnRH treatment, whereas $E_2$ production was not changed. We also demonstrated that FSH inhibits the suppressive effect of GnRH on $P_4$ production as the result of apoptosis. The present results suggest that GnRH agonist using in ovarian hyperstimulation protocol might induce the dysfunction of the ovary, but its function could be recovered by FSH. These results also will be expected to use as the basic data to elucidate the physiological role of GnRH and to develop new ovarian hyperstimulation protocols for IVF-ET.

• Journal of Ginseng Research
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• v.15 no.3
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• pp.188-191
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• 1991

The mild hydrolysis of ginsenosie Re with 50% acetic acid gave a prosapogenin mixture, 20(R)- and 20(S)-ginsenoside Rg2. The products were acetylated to give the peracetates, which were further converted into 20(R)- and 20(S)-ginsenoside Rh1 by the alcoholic alkaline treatment.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.350-354
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• 2008

전기/UV 공정에 사용하기 위해 일반적인 살균 램프인 UV-C 램프와 오존도 같이 발생하는 오존 등의 RhB 분해능을 고찰한 결과 오존 램프의 RhB 제거율이 UV-C램프보다 높은 것으로 나타났다. 전해질을 첨가하지 않은 전기/UV 공정에서 최적 전류는 1 A로 나타났다. 전기/UV 공정에서 RhB 제거의 경우 전기분해 공정과 UV 공정의 단일 공정의 RhB 농도감소와 전기/UV 복합 공정의 RhB 제거는 같아 공정의 시너지 효과는 관찰되지 않았다. 그러나 COD의 경우 전기분해 공정과 오존 램프에 의한 단일 공정의 COD 제거보다는 전기/UV 공정의 COD 제거농도가 높아 시너지 효과가 나타나는 것으로 사료되었다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2006.11a
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• pp.350-352
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• 2006

전류가 0.5 A에서 1.0 A로 변할 때 RhB 농도 감소가 크게 나타났으나 1.0 A 이상에서는 더 이상의 농도 감소가 없어 1 A가 최적 전류라고 사료되었다. 전극 간격을 1-3 cm로 변화시켜 RhB 농도감소를 고찰한 결과 전극간격에 따른 RhB 농도감소는 큰 차이를 보이지 않았으나 전력량을 감안하면 전극 간격이 좁을수록 유리하다고 사료되었다. 양극과 음극 모두 철 전극을 사용한 것이 RhB 농도가 감소가 가장 높았으며 전극 모양에 따른 RhB 농도 감소는 큰 차이를 보이지 않았다.

• YAKHAK HOEJI
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• v.45 no.4
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• pp.328-333
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• 2001

Ginsenoside Rh$_2$, a minor glycoside constituent of the red ginseng is known as an unique antitumor compound. Several attempts to prepare it in a large scale including semisynthesis from betulafolientriol, an 3-epimer of 20(S)-protopanaxadiol, has been reported. We have previously reported a synthesis of ginsenoside Rh$_2$from 20(S)-protopanaxadiol obtained by alkaline hydrolysis of total ginsenoside. The regioselective synthesis of this compound was achieved by protection of 12-OH group.