• 센서학회지
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• 제9권3호
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• pp.208-212
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• 2000

A protein based vision biomembrane was fabricated by adsorbing bacteriorhodopsin into electrochemically polymerized polypyrrole film substrate mainly through strong electrostatic interaction. The immobilized bacteriorhodopsin on the polypyrrole film was demonstrated by SEM and SRET. The light signal transducing function from the bacteriorhodopsin which was adsorbed into Polypyrrole film was evaluated by electroretinogram(ERG). A wave form analysis of the electroretinogram indicated that the adsorbed bacteriorhodopsin retained its activity and light signal was obtained from the protein for at least one month.

• 한국안광학회지
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• 제17권2호
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• pp.203-207
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• 2012

목적: 다른 생체신호와 마찬가지로 망막전도(electroretinogram, ERG) 신호도 측정시 잡음이 발생한다. 이 잡음을 효과적으로 제거하여 망막관련 진단의 정확도를 높이고자 하였다. 방법: ERG 신호에 60 Hz 잡음과 백색잡음을 발생시켜 샘플링 신호를 만들었다. 웨이브렛 변환과 대역통과 필터를 이용하여 잡음를 제거하였다. 푸리에 변환 스펙트럼을 이용하여 제거된 주파수를 비교하였다. 신호대잡음비(signal to noise ratio, SNR)를 이용하여 제거된 잡음을 수치적으로 비교하였다. 결과: 푸리에 변환 스펙트럼을 비교한 결과 웨이브렛 변환에서는 60 Hz 잡음은 완전히 제거 되었으며 백색잡음도 많이 제거되었다. 대역통과필터에서는 60 Hz와 백색잡음 남아 있었다. 신호대잡음비를 비교한 결과에서는 웨이브렛 변환은 22.8638, 대역통과 필터는 4.0961로 나타났다. 결론: 웨이브렛 변환을 이용하여 잡음 제거시 신호의 왜곡을 적게 발생시켜 제거할 수 있었다. 망막전도 신호를 이용한 망막 진단에 정확도를 높일 수 있을 것으로 기대된다.

• 한국안광학회지
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• 제19권2호
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• pp.247-252
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• 2014

목적: 단기간의 중심외주시 훈련 후 발생하는 신경의 재조직화의 특성과 호발 위치를 알아보고자 했다. 방법: 정상시력을 가진 성인 14명을 대상으로 21일 간 중심외주시 훈련을 하고 훈련 전후 광지각도와 다국소망막전위도를 측정하여 사후 분석했다. 결과: 중심외주시 훈련 전후 값을 비교한 광지각도 검사(p<0.047)에서 뿐만 아니라 다국소망막전위도 검사에서도 유의한 개선을 보였다(p<0.028). 결론: 시각 말초신경계는 재생이 불가능하지만 단기간의 중심외주시 훈련은 말초신경계에서 신경 재조직화를 발생시킨다.

• The Korean Journal of Physiology and Pharmacology
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• 제16권3호
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• pp.219-224
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• 2012

Understanding how the b-wave of the electroretinogram (ERG) is generated by full-field light stimulation is still a challenge in visual neuroscience. To understand more about the origin of the b-wave, we studied the contributions of gap junctions to the ERG b-wave. Many types of retinal neurons are connected to similar and different neighboring neurons through gap junctions. The photopic (cone-dominated) ERG, stimulated by a small light beam, was recorded from goldfish (Carassius auratus) using a corneal electrode. Data were obtained before and after intravitreal injection of agents into the eye under a photopic illumination level. Several agents were used to affect gap junctions, such as dopamine D1 and D2 receptor agonists and antagonists, a nitric oxide (NO) donor, a nitric oxide synthase (NOS) inhibitor, the gap junction blocker meclofenamic acid (MFA), and mixtures of these agents. The ERG b-waves, which were enhanced by MFA, sodium nitroprusside (SNP), SKF 38393, and sulpiride, remained following application of a further injection of a mixture with MFA. The ERG b-waves decreased following $N^G$-nitro-L-arginine methyl ester (L-NAME), SCH 23390, and quinpirole administration but were enhanced by further injection of a mixture with MFA. These results indicate that gap junction activity influences b-waves of the ERG related to NO and dopamine actions.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.250.1-250.1
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• 2002

DA-8159. a selective inhibitor of phosphodiesterase type 5 (PDE5: IC$\sub$50/ 5ng/$m\ell$). is being developed as a new treatment for erectile dysfunction. Since DA-8159 has been shown to inhibit PDE6 enzyme (IC$\sub$53ng/$m\ell$). we evaluated the effect of DA-8159 on electroretinogram (ERG) and retinal histopathology in rabbits. The effect of oral DA-8159 (5 to 30mg/kg) on ERG recordings was investigated at pre-treatment. 1 and 5 hrs after administration in rabbits. (omitted)

• 수산해양기술연구
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• 제40권2호
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• pp.132-137
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• 2004

스트로보광에 대한 어류의 전기생리학적 반응을 조사하기 위하여, 전갱이에 각각 4단계의 섬광빈도(1.7~25Hz)와 강도(56~415lx${\cdot}$s)로 광자극을 주어, 그에 대한 망막활동전위 (ERG)를 조사한 결과는 다음과 같다. 1. ERG 진폭은 스트로보광을 조사한 순간에 최대가 되고, 그 후 가장 작았다가 점차 커져서 안정되는 경향을 보였다. 2. 섬광빈도에 따른 ERG 진폭은 광자극 후 약 12~17분부터 안정되는 경향을 보였다. 3. 전갱이가 받는 자극량은 섬광빈도 10Hz 에서 가장 많았고, 스트로보광 강도가 약해짐에 따라 감소하였다. 4. ERG 진폭변화는 10Hz가 가장 컸고, 스트로보광의 강도가 감소함에 따라 적었다.

• Journal of Photoscience
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• 제7권4호
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• pp.161-167
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• 2000

Temperature-dependent electroretinogram responses were investigated in the dark adapted bullfrog eyes within the physiological temperature range 0-40$\^{C}$. In hypothermic process(25→0→25$\^{C}$), the amplitude of b-and c-wave decreased with lowering the temperature again. Both b-wave amplitude and threshold responses were maximal around 15$\^{C}$ during the temperature increment. Upon warming to room temperature again (25$\^{C}$), the b-wave amplitude was approximately doubled as compared to that of control without temperature changes. During the hyperthermic process (25→40→25$\^{C}$), however, the responses decreased with warming, and the wave amplitude failed to recover by cooling to 25$\^{C}$ again. As describe above, the recoveries of ERG in both processes show the striking difference. The hypothermia induces the amplification of the b-wave, that is, enhances the retinal function with the temperature recovery toward room temperature. While the hypertherima produces the decrease of the b-wave even though recovered to room temperature, which indicates an irreversible retina. The morphological alteration is shown both hypothermic and hyperthermic process, such as an appearance of large vacuoles and degenerating outer segments, more intense in hyperthermia, similar to light induced damage.

• 한국임상수의학회지
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• 제29권2호
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• pp.124-129
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• 2012

본 연구의 목적은 건강한 내원견을 대상으로 측정한 망막전위도에 나이 및 성별이 어떠한 영향을 미치는지 알아보는데 있다. 보호자가 임상 실험에 참가하는 것을 동의한 34두의 개를 medetomidine과 tiletamine-zolazepam혼합제로 전신마취하여 ISCEV에서 권고하는 진단용 프로토콜에 따라 망막전위도를 측정하였다. 성별간 비교시는 cone 반응의 a파의 지연시간에서 그리고 나이별 비교시 Hi-int R & C 반응의 a파 지연시간에서 유의성을 각각 나타내었다 (P < 0.05). 나머지 ERG반응들은 나이와 성별에 영향을 받지 않는 것으로 나타났다.

• Journal of Photoscience
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• 제2권2호
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• pp.63-67
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• 1995

Zinc plays a key role in genetic expression, cell division, and growth and is essential for the function of more than 200 enzymes; effects of zinc deficiency induce many syndromes, including abnormal visual adaptation. The pigment epithelium (EP) contains high concentrations of zinc in humans and in animals and it participates in threshold elevation, visual sensitivity increment, and acceleration of rhodopsin regeration during visual adaptation. The origin of c-wave of electroretinogram(ERG) is not only pigment epithelium as shown in present research, but also other cell layers, perhaps the photoreceptors. We propose zinc as a candidate for an internal messenger which participates in signal amplification.

• Journal of Photoscience
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• 제7권3호
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• pp.115-121
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• 2000

Although there are high concentrations of zinc and taurine in ocular tissue, their exact role and correlation in the visual process are not clear. The purpose of present study was to clarity this point using electroretinogram (ERG) recording and spectrophotometer measurements before and after zinc and taurine treatment in bullfrog's eye. The optimal zinc concentration used in this study was 10$^{-2}$ M ZnCl$_2$120 ${mu}ell$/12$m\ell$ ringer solution while the optimal turine concentration was 10$^{-2}$ M taurine 12${mu}ell$/12$m\ell$ ringer solution. For the effects of zinc and taurine on the retinal function, the changes of ERG parameters (especially threshold and b-wave) and absorption spectra were observed before and after treatment. It is noteworthy that high concentrations of zinc and taurine present in the retinal pigment epithelium and the retina. Our results indicate that dark-adapted ERG threshold became elevated and the peak amplitude of b-wave was increased with zinc and taurine treatment. Furthermore there are some synergism effects between zinc and taurine as a result of co-treatment. In spectral scan, absorbance increment due to zinc and taurine treatment was shown over the whole range of spectral range (300-750 nm) with some differences in absorbance increment depending on the case of treatment. As the results of above we believe that zinc and taurine, which are abundant in the retinal pigment epithelium and the retina particularly, may be essential factors for visual process, have some synergism with each other and be required to improve the visual sensitivity during visual adaptation.