산화물 고온 초전도에 관한 연구

權五興 관동대학교 2000 關大論文集 Vol.28 No.2

The substitution of transition elements (IVb, Va, and VIa group) or non-Transition elements(IVb and Vb ground)for Bi ions in the oxide was performed, and the effect of substitution on Tc, Jc, Magnetization, temperature dependence of resistivity or magnetization and variation of solid phase was investigated. It was found that the substitution of P is the most effective and then the high Tc phase is formed in a large quantity by replacing Bi ions with 30% of ions.

해마 theta리듬과 pyramidal neuron의 세포내 특성과의 상관관계

권오흥,조진화,남순현,김현정,최병주,김영진,이만기 大韓小兒齒科學會 1998 大韓小兒齒科學會誌 Vol.25 No.4

Eledctrophysiological phenomena of pyramidal cells in the CAI area of the dorsal hippocampus were recorded from and filled with neurobiotin in anesthetized rats. The electropharmacological properties of membrane as well as the cellular-synaptic generation of rhythmic slow activity (theta)were examined. The intracellular response characteristics of these pyramidal cells were distinctly different from responses of inteneurons. Pyramidal cells had a high resting membrane potential, a low input resistance, and a large amplitude action potential. A afterhyperpolarization was followed a single action potential. Most of pyramidal cells did not display a spontaneous firing. Pyramidal cells displayed weak inward rectification and anodal break excitation. The slope of the frequency-current relation was 53.4 Hz/nA for the first interspike interval and 15.9 Hz/nA for the last intervals, suggesting the presence of spike frequency adaptation. Neurobiotin-filled neurons showed pyramidal morphology. Cells were generally bipolar dendritc processes ramifying in stratum lacunosum-moleculare, radiatum, and oriens. Commissural stimulation discharged pyramidal cells, followed by excitatory and inhibitory postsynaptic potentials (EPSPs and IPSPs). The frequency of theat-related membrane potential oscillation was voltage-independent in pyramidal neurons. At strong depolarization levels (less than 30 mV) pyramidal cells emitted sodium spike oscillation, phase-locked to theta. The observations provide direct evidence that theta-related rhythmic hyperpolarization of principal cells is brought by the rhythmically discharging interneurons. Furthermore, the findings in which interneurons were also paced by rhythmic inhibitory postsynaptic potentials during theta suggest that they were periodically hyperpolarized by their GABAergic septal afferents.

마취된 흰쥐 해마 주신경세포의 형태적 및 전기생리적 특성

권오흥 慶北大學校 齒科大學 1996 慶北齒大論文集 Vol.13 No.-

본 연구의 논문의 목적은 주위 세포들과 완전한 상태로 신경망이 보존된 in vivo 연구모델을 사용하여 경련발작의 가장 취약한 부위인 해마의 주 세포층 세포들을 기능적으로 구분하고자 하였고 전기생리적 변동 여부를 확인하여 신경망 기능에 기여하는 역할을 파악하고자 하였다. 또한 세포내로 측정된 해마 주세포의 발화 pattern과 세포외부로 측정된 network pattern과의 관계를 연관지워서 신경세포의 기능을 설명하였으며 이러한 실험을 통하여 경련발작 및 이에 수반되는 뇌손상에 대한 기초적 기전을 제시하였고 그 실험모델을 확립하고자 하였다. 마취된 흰쥐를 사용하여 해마의 CA1 영역에 존재하는 pyramidal cell을 holding하고 신경생리학적 변수를 측정한 후 neurobiotion를 채워서 형태학적 추적을 하였다. 이 세포의 세포내 반응의 특징은 높은 휴지기 세포막 전위, 낮은 input resistance, 그리고 큰 action potential을 가진다는 것이다. 단일 action potential 후 AHP가 나타났으며 대부분의 세포에서 자발적 발화 양태가 미약했다. Frequency-current relation은 53.4 Hz/nA 및 15.9Hz/nA (first ISI 및 last ISI)로서 spike frequency의 적응현상이 뚜렷이 나타났다. Neurobiotion으로 채워진 세포는 형태학적으로 pyramidal 모양을 지녔고 bipolar형의 dendrite 그리고 oriens 층에서 부터 lacunosum-moleculare 층까지 분지를 하였다. Commissural afferent 자극으로 pyramidal cell의 전위가 변화되었으며 전형적인 EPSP 및 IPSP 반응을 나타내었다. 세포내 전기 신호 전체의 background에서 자발적 action potential이 발생하여 리드믹한 파형을 형성하는 경우에는 CA1 pyramidal 층에서 기록한 세포외 theta리듬과 그 파형을 동시에 비교하였는데 세포외 theta 파의 negative peak에 세포내 AP발화가 위상 일치되는 경향이 있었다. 그러나 세포외 theta파가 발생되지 않은 조건에서는 세포내 AP 발화와의 위상일치가 나타나지 않았다. 이러한 세포내 AP 발화가 theta 파형을 형성하는 여부는 세포막 전위로서 조절할 수 없었고 신경세포의 조건과도 관계가 없었다. 다만 이들 파의 크기와 위상 변이는 신경세포의 분극 수준에 상당히 의존적이었다. 세포막 전위가 일정한 폭으로 진동을 나타내었는데 항상 세포외부 theta 파형의 rhythmicity에 비하여 규칙성이 저하된 상태를 보여 주었다. Tail pinching 등과 같은 인위적인 외부 자극으로 theta파를 유발시키면 신경세포는 과분극이 되고 이에 따라 intracellular oscillation은 action potential을 생성시키는 탈분극 수준에 거의 도달하지 않았다. 세포 외부 theta 파형이 나타나지 않은 조건에서 pyramidal cell을 지속적인 탈분극 또는 과분극을 시켰으나 세포막전위가 theta frequency의 rhythmic oscillation형태로 변화되지 않았다. 그러나 alpha 및 beta 파와 같은 12-30 Hz rhythmic oscillation이 종종 관찰되었다. 이상의 본 연구 결과로서 해마의 기능적 특이성에 대한 형상화 기전을 미루어 보면 우선 Schaffer collateral-commissual pathway 자극에 의하여 시냅스 후 반응이 야기되어 pyramidal cell의 population size를 한정함으로써 hippocampal cell들의 공간적 발화 양태가 다양하게 될 것으로 믿어 진다. Pyramidal cells in the CA1 area of the dorsal hippocampus were recored from and filled with neuroboitin in anesthetized rats. The extent of thier dendrites and the electropharmacological properties of membrane as well as the cellular-synaptic generation of rhythmic slow activity (theta) were examined. The intracellular response characteristics of these pyramidal cells were distinctly different form responses of interneurons. Pyramidal cells had a high resting membrane potential, a low input resistance, and a large amplitude action potential. A afterhyperpolarization was followed a single action potential. Most pyramidal cells did not display a spontaneous firing. Pyrmidal cell displayed weak inward rectification and anodal break excitation. The slope of the frequency-current relation was 53.4 Hz/nA for the first interspike interval and 15.9 Hz/nA for last intervals, suggesting the presence of spike frequency adaptation. Neurobiotin-filled neurons showed pyramidal morphology. Cells were generally bipolar dendritc processes ramifying in staratum lacunosum- moleculare, radiatum, and oriens. Commissural stimulation discharged pyramidal cells, followed by excitatory and inhibitory postsynaptic potentials (EPSPs and IPSPs). The frequency of theta-related membrane potential oscillation was voltage-independent in pyramidal neurons. At strong depolarization levels (less than 30 mV) pyramidal cells emitted sodium spike oscillation, phase-locked to theta. The observations provide direct evidence that theta-related rhythmic hyperpolarzation of principal cells is brought by the rhythmically discharging interneurons. Furthermore, the reports that interneurons were also paced by rhythmic inhibitory postsynaptic potentials during theta suggest that they were periodically hyperpolarized by their GABAergic septal afferents.

E-초등학교 어린이의 영구치 맹출시기 및 순서

권정현,최병재,이제호,김성오,손흥규,최형준 大韓小兒齒科學會 2009 大韓小兒齒科學會誌 Vol.36 No.2

치아 맹출은 나이, 성별, 인종, 시대에 따라 시기 및 순서의 차이가 있으나, 교과서에 인용되어 임상에서 사용되는 영구치 맹출 및 치근 형성에 대한 자료는 1933년 Logan과 Kronfeld가 발표한 것이므로 현재 한국 어린이의 영구치 맹출 경향과 차이가 있을 수 있다. 따라서 이번 연구의 목적은 한국 어린이의 영구치 맹출연령을 구하고, 이를 근거로 맹출순서를 알아보며, 이전 국내외 연구자료와 비교하여 차이를 알아보는 것이다. 이에 1998년부터 2005년까지 연세대학교 치과대학병원 소아치과에 내원하여 구강검진을 시행한 E-초등학교의 어린이 중 만 6세에서 만 12세의 2,619명 (남자 1,307명, 여자 1,312명)의 자료를 수집하여 영구치의 맹출시기 및 순서에 대해 연구 한 바 다음과 같은 결론을 얻었다. 1. 상악의 영구치 맹출시기는 중절치는 남자 만 6.81세, 여자 만 6.73세, 측절치는 남자 만7.78세, 여자 만7.65세, 견치는 남자 만10.48세, 여자 만9.92세, 제1소구치는 남자 만9.76세, 여자 만9.63세, 제2소구치는 남자 만10.66세, 여자 만10.49세, 제1대구치는 남자 만6.39세, 여자 만6.26세, 제2대구치는 남자 만12.13세, 여자 만 12.03세로 나타났다. 2. 하악의 영구치 맹출시기는 중절치는 남녀 모두 정확한 시기의 측정은 불가능하였지만, 만 6.08세 이전에 맹출한다는 것을 추정 할 수 있었고, 측절치는 남자 만6.78세, 여자 만6.65세, 견치는 남자 만9.76세, 여자 만9.05세, 제1소구치는 남자 만9.82세, 여자 만9.59세, 제2소구치는 남자 만10.67세, 여자 만10.52세, 제1대구치는 남자 만6.22세, 여자 만6.12세, 제2대구치는 남자 만11.58세, 여자 만 11.14세로 나타났다. 3. 맹출순서는 상악은 제1대구치, 중절치, 측절치, 제1소구치, 견치, 제2소구치, 제2대구치 순이었고, 하악은 중절치, 제1대구치, 측절치, 견치, 제1소구치, 제2소구치, 제2대구치 순이었다. 4. 모든 영구치에서 남자보다 여자가 빨리 맹출하였으며, 상악은 약 0.19세, 하악은 약 0.29세 먼저 맹출하였다. 5. 남녀 모두 상악은 측절치와 제1소구치 사이, 하악은 측절치와 견치 사이에 휴지기가 있었고, 남자의 휴지기는 상악 1.98년, 하악 2.98년, 여자는 상악 1.98년, 하악 2.40년이었다. The purpose of this study was to present new data on the timing and sequence of permanent teeth emergence and to compare these findings with the results of earlier studies. The dental examinations had been performed to E-elementary school students, who visited the Yonsei University Dental Hospital between 1998 and 2005; 1,307 boys and 1,312 girls with the age ranging from 6 to 12 years old. The followings were concluded. 1. Eruption time of the maxillary permanent teeth is as follows, It was 6.81 years in male and 6.73 years in female for the central incisor, 7.78 years in male and 7.65 years in female for the lateral incisor, 10.48 years in male and 9.92 years in female for the canine, 9.76 years in male and 9.63 years in female for the first premolar, 10.66 years in male and 10.49 years in female for the second premolar, 6.39 years in male and 6.26 years in female for the first permanent molar, and 12.13 years in male and 12.03 years in female for the second permanent molar. 2. Eruption time of the mandibular permanent teeth is as follows. The central incisor could not be determined in this study, but it is assumed to erupt before the age of 6.08. In the mandible, eruption time was 6.78 years in male and 6.65 years in female for the lateral incisor, 9.76 years in male and 9.05 years in female for the canine, 9.82 years in male and 9.59 years in female for the first premolar, 10.67 years in male and 10.52 years in female for the second premolar, 6.22 years in male and 6.12 years in female for the first permanent molar, and 11.58 years in male and 11.14 years in female for the second permanent molar. 3. The eruption sequence is as follows. In the maxilla, the first permanent molar erupted first, followed by the central incisor, the lateral incisor, the first premolar, the canine, the second premolar, and the second permanent molar. In the mandible, the central incisor erupted first, followed by the first permanent molar, the lateral incisor, the canine, the first premolar, the second premolar, and the second permanent molar. 4. Tooth eruption occurred earlier in female compared to male by average of 0.19 year in the maxilla and 0.29 year in the mandible. 5. In both male and female, the hiatus (interval of rest) occurred between the emergence of lateral incisor and first premolar in the maxilla while it was observed between the lateral incisor and canine in the mandible. Male had a hiatus of 1.98 years in the maxilla and 2.90 years in the mandible, while the female's were 1.98 years and 2.40 years, respectively.

호밀 (Secale cereale L.)유식물의 질산환원효소의 활량과 단백질함량에 관한 Cycloheximide의 영향

권오용,이영하,오희목,박흥순,이진철 충남대학교 자연과학연구소 1988 忠南科學硏究誌 Vol.15 No.2

This work was accomplished with 6 day-old rye (Secale cereale L.) seedlings to determine the effect of the antibiotics by cycloheximide on in vivo nitrate reductase activity, protein and RNA content. The nitrate reductase activity by treating 0.1μM and 0.1 mM cycloheximide was lower than that of the control group. The optimum pH for the nitrate reductase of the control group was 7.6 in the range of pH 5.6-8.0, but, in the case of 0.1mM cycloheximide treatment group, the optimum pH was decreased to 6.8 within the weak the acid region. The protein content of shoot and root in the 0.1μM and 0.1 mM cycloheximide treatment groups were respectively found at the 96%, 82% level of that in the control group. In the higher cycloheximide treatment (0.1 mM CH), not only nitrate reductase activity and protein content but also RNA content was greatly decreased. In this fact, it was suggested that the 0.1 mM cycloheximide had affected on the RNA polymerase. On the basis of there results, it was concluded that the decreased nitrate reductase activity by treating cycloheximide occurred primarily according to the decreased nitrate uptake, and the decreased protein and RNA content depended upon the results of the direct and indirect effect of cycloheximide on the protein synthesis.

밀(Triticum aestivum L.) 유식물이 질산 환원효소 활량에 대한 Sodium Azide의 영향

권오용,박흥순 충남대학교 자연과학연구소 1989 忠南科學硏究誌 Vol.16 No.1

These work was accomplished with 6 day-old wheat(Triticum aestivum L.)seedlings to determine the effect of the inhibitors by sodium azide on in vivo nitrate reductase activity. When the sodium azide was treated according to each concentration (0.01∼100mM), the inhibition occurred greatly in the shoots and it occurred slightly in the roots of wheat seedlings. After treating with 1.0mM sodium azide, optimum pH was 7.0 both in shoots and roots. Both the shoots and roots of wheat seedlings was greatly inhibited in the second hours, when 1.0mM sodium azide was treated as a function of time. The inhibition in 10mM KNO_3 concentration appeared greatly, when 1.0mM sodium azide was treated with each concentration of KNO_3.

Neural-fuzzy Pattern Matching Word Recognition

OH HEUNG KWON,CHEOLSOO BAE 대한전자공학회 1998 International Conference on Electronics, Informati Vol.1998 No.8

Discrepancy in General Surgery Medical Terminology Between South and North Korea

Heung-Kwon OH,Keunyoung HUR,Do-Eon PARK,Hyun Hui YANG,Dayoung KO,Min-Hyun KIM,Myung Jo KIM,Sung Il KANG,Duck-Woo KIM,Sung-Bum KANG 대한외과학회 2017 대한외과학회 학술대회 초록집 Vol.2017 No.11

Functional and histological evidence for the targeted therapy using biocompatible polycaprolactone beads and autologous myoblasts in a dog model of fecal incontinence.

Oh, Heung-Kwon,Lee, Hye Seung,Lee, Jin Ho,Oh, Se Heang,Lim, Jae-Young,Ahn, Soyeon,Hwang, Ji-Yeon,Kang, Sung-Bum Lippincott 2015 Diseases of the colon and rectum Vol.58 No.5

<P>Injection of bulking agents into the anal canal is limited by several factors, including biological resorption, particle migration, and ongoing degradation of the injected bulking agent.</P>

Open Incisional Hernia Repair

Heung-Kwon Oh 대한외과학회 2017 대한외과학회 학술대회 초록집 Vol.2017 No.11