• Asian-Australasian Journal of Animal Sciences
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• 제11권1호
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• pp.78-83
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• 1998

The objective of this study was to investigate the responsiveness of hypophysis and gonads to synthetic GnRH among prepubertal buffalo heifers at 12 months of age. Peripheral plasma FSH, LH, estradiol and progesterone level were measured in blood samples collected at 1 hr before and up to 18 days subsequent to the administration of $200{\mu}g$ GnRH (n=6) or saline (n=6) in Murrah buffalo heifers. The pretreatment peripheral plasma FSH, LH, estradiol and progesterone among GnRH treated heifers were $7.35{\pm}0.45ng/ml$, $1.08{\pm}0.3ng/ml$, $22.93{\pm}1.06pg/ml$ and $0.27{\pm}0.04ng/ml$ respectively. A quick elevation (p < 0.01) of FSH and LH within five min of GnRH administration was observed in all geifers. Although the peak FSH $(89.57{\pm}23.43ng/ml)$ and LH $(7.52{\pm}3.08ng/ml)$ reached by 10 min of GnRH administration, yet the animals differed both in terms of their amplitude response of FSH and LH release as well as in terms of time which animals took to exhiit maximum response to GnRH administration. The GnRH administration did not cause alteration in plasma estradiol and progesterone level. The present study suggests that the pituitary of 12 month buffalo heifers has capacity to synthesize and store of gonadotropin and have developed receptors for GnRH for a spike of gonadotropin release.

• 한국임상수의학회지
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• 제20권2호
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• pp.212-219
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• 2003

The effect of GnRH and/or hCG on the implantation, pregnancy, and the concentration of plasma estradiol and progesterone were studied in pregnant rats. GnRH 50, or 100ug and/or hCG 50 or 100 IU were administered once on day 2 or 9 of gestation, respectively. Rats were autopsied on days 8 or 16. Administration of GnRH on day 2 did not induce the prevention of implantation and termination of pregnancy but was able to induce termination of pregnancy administering on day 9. Administration of hCG induced delayed implantation on day 2 and termination of pregnancy on day 2 and 9. Administration of GnRH concomitant with hCG had no effect on prevention of implantation on day 2 but induced termination of pregnancy with a very increased fetal resorption on day 2 and with a moderate increased fetal resorption on day 9. Administration of GnRH concomitant with hCG on day 2 induced more increased termination of pregnancy compared to injection of GnRH or HCG and opposite result was observed on day 9. Plasma estradiol and progesterone concentrations by administering GnRH and/or hCG had no effect on the termination of pregnancy the pregnant rats.

• 한국환경과학회지
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• 제16권1호
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• pp.1-8
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• 2007

Atmospheric photochemistry of $O_3-NOx-RH$ were considered theoretically, to clarify the reasons for the different trends of between the formation of photochemical oxidants (Ox) and its primary pollutants for the Low-and High-NOx regimes. Equations of OH, $HO_2$, and production of ozone ($O_3$) as a function of nitrogen oxides (NOx) and reactive hydrocarbons (RH) were represented in this study. For the Low-NOx regime, $HO_2$ radical is proportional to RH but independent of NOx. OH radical is proportional to NOx but inversely-proportional to RH. $O_3$ production is proportional to NOx but has a weak dependence on RH. For the High-NOx regime, OH and $HO_2$ radicals concentrations and $O_3$ production are proportional to RH but inversely-proportional to NOx. In addition, the Osaka Bay and surrounding areas of Japan were evaluated with the mass balance of odd-hydrogen radicals (Odd-H) using CBM-IV photochemical mechanism, in order to distinguish the Low- and High-NOx regimes. The Harima area (emission ratio, RH/NOx = 6.1) was classified to the Low-NOx regime. The Hanshin area (RH/NOx = 3.5) and Osaka area (RH/NOx = 4.3) were classified to the High-NOx regime.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.84-84
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• 2010

We present an in-situ study of the interaction of a bimetallic Rh50Pd50 bulk crystal with O2, CO, and NO using ambient pressure x-ray photoelectron spectroscopy and compare it to results for 10 nm nanoparticles with the same overall composition. The surface of the bulk crystal has less Rh present under both oxidizing and reducing conditions than the nanoparticles under identical conditions. Segregation and oxidation/reduction proceeds quicker and at lower temperature for nanoparticles than for the bulk crystal. The near surface of the Rh50Pd50 bulk crystal after high temperature vacuum annealing is ca. 9% Rh measured by XPS. Heating in 0.1 Torr O2 to $350^{\circ}C$ increases the Rh surface composition to ca. 40%. The surface can then be reduced by heating in H2 at $150^{\circ}C$, leading to a reduced surface of 30% Rh. Titration of CO from this Rh-rich surface proceeds at a much lower pressure than on the Rh-deficient starting surface.

• 한국임상수의학회지
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• 제3권1호
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• pp.227-233
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• 1986

A total of 600 Holstein cows in Chonnam province was examined to make a diagnosis on the ovarian follicular cyst. By clinical signs and rectal examination, 57 cows were found to have ovarian follicular cyst. Attempts were made to treat the cows which had ovarian follicular cyst with GnRH, HCG respectively. The results obtained were summarized as follows : 1. The rates of estreous induction with GnRH or HCG were 91.4%, 77.2%, respectively. The GnRH treated group was showed significantly higher than HCG treated group. The mean days from the GnRH or HCG treated to estrum were 25.1 and 23.5 days, respectively. 2. The Conception rates with GnRH or HCG treatment were 78.2% and 76.5％, respectively. 3. Services per conception with GnRH or HCG treatment were 1.5 and 2.1 respectively. 4, Days from GnRH or HCG treatment to concept were 38.2 and 45.8 days, respectively. 5. Intramuscular injection with GnRH and intraovarian injection with HCG were revealed the most effective routes in all the other routes.

• Journal of Pharmaceutical Investigation
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• 제28권2호
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• pp.99-107
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• 1998

The objective of this study was to develop effective oral formulations of rhEGF for gastric ulcer healing using polycarbophil. hydroxypropylcellulose(HPC) and sucralfate as its bioadhesive bases. Cytoprotective effects of rhEGF, cell proliferation and differentiation. on the ulcers induced by ethanol or acetic acid in rats were studied. rhEGF release from HPC formulation was much faster than that from polycarbophil formulation. HPC formulation combined with small amount of sucralfate showed much slower release of rhEGF than only HPC base only. rhEGF preparations with bioadhesive polymers showed better effects on the healing of gastric ulcers than EGF solution when administered orally. When rhEGF preparations were administered at once and the animals were under starvation, polycarbophil formulation showed better effect on gastric ulcers than HPC formulation. Otherwise, when rhEGF preparations were given more than three times and the rats were fed normally, HPC formulation showed good healing efficacy of ulcers compared to polycarbophil formulation. rhEGF showed dose-dependent effect on the healing of both chronic and acute ulcers.

• 대한약리학회지
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• 제30권1호
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• pp.19-28
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• 1994

흰쥐의 뇌하수체 전엽배양세포에 gonadotropin-releasing hormone (GnRH)을 처리하였을 때 시간이 경과함에 따라 GnRH농도에 비례하여 luteinizing hormone(LH)의 분비가 증가하였으며, 2시간까지 급격하게 증가하였다. 또한 GnRH를 처리하였을때 ${\alpha}$ subunit mRNA의 농도는 증가하지 않았으나 $LH{\beta}$ subunit mRNA의 농도는 GnRH 농도에 비례하여 증가하였으며, GnRH 처리후 6시간 이후부터 유의하게 증가하였다. 특히 최종농도가 $2{\times}10^{-10}M$이 되도록 GnRH를 처리하였을 때 $LH{\beta}$ subunit mRNA 농도가 2.7배 정도 최대로 증가하였다. 또한 estradiol을 단독으로 또는 GnRH와 동시에 처리하였을때 LH분비가 증가하지 않았으나 progesterone을 GnRH와 동시에 처리하였을때 LH분비가 유의하게 증가하였다. 또한 $LH{\beta}$ subunit mRNA의 농도는 estradiol및 progesterone을 단독으로 또는 GnRH와 동시에 처리하였을때 난소호르몬 농도에 의존적으로 $LH{\beta}$ subunit mRNA의 농도가 증가하였다. Estradiol에 의한 $LH{\beta}$ subunit mRNA의 증가양상은 estrogen 길항제인 LY117018에 의하여 유의하게 감소하였다. 이러한 결과로 보아 GnRH는 steady state $LH{\beta}$ subunit mRNA 농도에 영향을 미치므로써 LH분비 및 LH subunit 생합성을 조절하며 난소호르몬은 뇌하수체에 직접 작용하여 LH분비 및 LH subunit 생합성에 영향을 주는 것으로 보인다.

• 대한약리학회지
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• 제23권2호
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• pp.57-75
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• 1987

Two modalities of gonadotropin secretion, pulsatile gonadotropin and preovulatory gonadotropin surge, have been identified in the mammals. Pulsatile gonadotropin secretion is modulated by the pulsatile pattern of GnRH release and complex ovarian steroid feedback actions. The neural mechansim that regulates the pulsatile release of GnRH in the hypothalamus is called "GnRH pulse generator". Ovarian steroids, estradiol and progesterone, appear to exert thier feedback effects both directly on the pituitary to modulate gonadotropin release and on a hypothalamic site to modulate GnRH release; estradiol primarily affects the amplitude while progesterone decreases the frequency of the pulsatile GnRH. Steroid hormones are known to affect catecholamine transmission in brain. MBH-POA is richly innervated by NE systems and close apposition of NE terminals and GnRH cell bodies occurs in the MBH as well as in the POA. NE normally facilitates pulsatile LH release by acting through ${\alpha}-receptor$ mechanism. However, precise nature of facilitative role of NE transmission in maintaining pulsatile LH has not been clearly understood. Close apposition of DA and GnRH terminals in ME might permit DA to influence GnRH release. Action of DA transmission probably is mediated by axo-axonic contacts between GnRH and DA fibers in the ME. Dopamine transmission does not normally regulate pulsatile LH release, but under certain conditions, increased DA transmission inhibit LH pulse. Endogenous opioid acts to suppress the secretion of GnRH into hypophysial portal circulation, thereby inhibiting gonadotropin secretion. However, an interaction between endogenenous opioid peptides and gonadotropin release is a complex one which involves ovarian hormones as well. LH secretion appears to be most suppressed by endogenenous opioids during the luteal phase, at a time of elevated progesterone secretion. The arcuate nucleus contains not only cell bodies for GnRH and ${\beta}-endorphin$ but also a dense aborization of fibers suggesting that GnRH release is changed by the interactions between GnRH and ${\beta}-endorphin$ cell bodies within the arcuate nucleus. The frequency and amplitude of pulsatile LH release seem to be increased during the preovulatory gonadotropin surge. Estradiol exerts positive feedback action on the hypothalamo-pituitary axis to trigger preovulatory LH surge. GnRH is also crucial hormonal stimulus for preovulatory LH surge. It is unlikely, however, that increased secretion of GnRH during the preovulatory gonadotropin surge represents an obligatory neural signal for generation of the LH discharge in primates including human. Modulation of preovulatory LH surge by catecholamines has been studied almost exclusively in rats. NE and E may be involved in distinct way to accumulate GnRH in the MBH and its release into the hypophysial portal system during the critical period for LH surge on proestrus in rats. However, the mechanisms whereby augmented adrenergic transmission may facilitate the formation and accumulation of GnRH in the ME-ARC nerve terminals before the LH surge have not been clearly understood.

• 대한화학회지
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• 제33권5호
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• pp.516-521
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• 1989

주게원자가 질소원자와 산소원자인 N2O2형 네자리 리간드 ethylenediamine-N,N'-S-${\alpha}$-isobutylacetic acid(SS-eniba)의 디클로로 로듐(III)$[Rh(SS-eniba)Cl_2]$-의 합성에서 ${\Delta}-s-cis$ 및 ${\wedge}-uns-cis$ 이성체를 분리하였다. ${\Delta}-s-cis-[Rh(SS-eniba)Cl_2]$- 착물과 S-methyl-L-cystcine(Smc)의 반응으로부터 ${\Delta}-s-cis-[Rh(SS-eniba(Smc)]^+$ 착물을 합성한 다음 $H_2O_2$를 이용한 산화반응으로부터 배위된 황원자가 sulfoxide 원자단으로 산화된 ${\Delta}-s-cis-[Rh(SS-eniba)(Smc-o)]^+(Smc-o=S-methyl-L-cysteine sulfoxide)$ 착물이 형성됨을 관찰하였다. 한편 S-methyl-L-cysteine을 $H_2O_2$와 반응시켜 sulfoxide 원자단으로 산화시킨 S-methyle-L-cysteine sulfoxide의 합성을 별도로 진행한 후 ${\Delta}-s-cis-[Rh(SS-eniba)Cl_2]^+$ 착물에 배위시켜 표준착물인 ${\Delta}-s-cis-[Rh(SS-eniba)(Smc-o)]^+$를 합성한 다음 ${\Delta}-s-cis-[Rh(SS-eniba(Smc)]^+$ 착물을 산화시켜 얻은 ${\Delta}-s-cis-[Rh(SS-eniba)(Smc-o)]^+$착물과 비교하여 배위된 항원자가 sulfoxide 원자단으로 전환되었음을 또한 관찰하였다.

• 한국수산과학회지
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• 제32권3호
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• pp.266-270
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• 1999

성숙 점농어 뇌에서 세 종류의 생식소자극호르몬 분비호르몬 (GnRH)의 소재를 면역조직화학법에 의해 동정하였다. sGnRH 양성 신경세포체는 후각망울, 복측 종뇌와 전시각 지역에 분포하였다. 양성 신경섬유는 후각망울에서부터 척수에 이르기까지 다양하게 분포하였다. 면역신경섬유는 뇌의 전지역인 후각망울, 종뇌, 시각시개, 소뇌, 연수 그리고 머리쪽 척수에서 발견되었다. 대부분의 경우 이들은 모두 다발을 형성하지는 않았다. 그러나 후각망울에서 뇌하수체로 뻗어있는 양성 신경섬유는 가장 뚜렷하였다. cGnRH-II 양성 신경세포체는 후엽에서 발견되었다. 그러나 cGnRH-II 면역신경섬유도 후각망울에서 뇌하수체로 뻗은 면역신경섬유를 제외하고는 기본적으로 sGnRH 양성 신경섬유와 분포가 유사했다. 이것은 점농어 뇌에서 sGnRH와 cGnRH-II가 알려진 내인성 펩타이드이며, 이들이 다양한 신경내분비 기능을 수행할 것이라는 점을 의미한다. sGnRH는 GTH의 분비를 조절 할 뿐만 아니라 신경전달조절자로서, cGnRH-II는 단지 신경전달조절자로서 작용할 것으로 생각된다.