젊은 성인에서 흡연에 의한 상완동맥 내피기능의 부전에 관한 연구

이상철,권영주,방덕원,이선해,이보영,김지욱,김영훈,온영근,현민수,김성구 순천향의학연구소 2002 Journal of Soonchunhyang Medical Science Vol.8 No.1

Background and Objectives : Cigarette smoking is a major factor and the most modifiable risk factor for atherosclerosis. Endothelial dysfunction is an early event in atherosclerosis, before the structural change of the systemic arteries. We hypothesized that endothelial dysfunction might be present in the systemic arteries of young adult smokers and that this might be dose-dependent phenomenon. Therefore, we try to certify that smoking is associated with endothelial dysfunction in healthy young adults without other risk factor of atherosclerosis. Subjects and Methods : we studied noninvasively 29 subjects aged 3 to 4 decades without other risk factor of atherosclerosis, they were composed of the two groups, current smokers(n=15) and nonsmokers(n=14). Smoking history varied from 3 to 20 pack years. Using high-resolution ultrasound, vessel diameter and mean flow rate were measured at rest, during reactive hyperemia(with flow-mediated endothelium-dependent dilation), and after sublingual nitroglycerin(NG-induced endothelium-independent vasodilation). Result : Flow mediated endothelium dependent dilation was observed in the control subjects (9.4±3.44%) but was impaired in the smokers(5.8±2.51%)(p=0.004). NG-induced endothelium independent dilation is no difference in all subjects. Conclusion : Cigarette smoking is associated with endothelial dysfunction in healthy young adults.

유치 수복물에 따른 주변 법랑질의 탈회 저항성 : QLF를 이용한 연구

권해숙,현홍근,김영재,김정욱,장기택,김종철,한세현,이상훈 大韓小兒齒科學會 2010 大韓小兒齒科學會誌 Vol.37 No.1

본 연구에서는 유치 수복물의 불소 방출 여부에 따른 주변 법랑질의 탈회 저항성과 재광화 효과를 살펴보고자 하였다. 건전 유전치 48개를 16개씩 임의로 세 군으로 나누어, FiltekTM Z250(1군), F2000(2군), KetacTM N100(3군)을 사용하여 제조사의 지시에 따라 충전하였다. 3일 동안 인공 우식 병소를 유발한 후, 14일 동안 인공 타액에 담가 재광화를 유발하였다. Quantitative light-induced fluorescence(QLF)를 이용하여 실험 단계와 시간에 따른 무기질 소실량(ΔQ)의 변화를 관찰한 결과는 다음과 같다. 1. 탈회가 일어난 인공 우식 병소의 ΔQ 값은 3군, 2군, 1군 순으로 작게 나타났고, 이 중 3군은 1군에 비해 유의한 탈회 저항성을 보였다. 2. 1군, 2군, 3군 모두 재광화 1일 후부터 초기 인공 우식 병소의 ΔQ 값과 비교 시 유의한 차를 보였으며, 관찰 기간 동안 지속적인 증가 양상을 나타내었다. 3. 재광화 속도를 의미하는 Δ(ΔQ)/일 값은 각 군에서 처음 1일 동안 유의성 있게 크게 나타났으며, 그 이후 급속히 감소하였다. 4. 수복 재료에 따른 재광화 정도는 각 군 간에 유의한 차이가 없었다. The objective of this in vitro study was to detect and monitor demineralization and remineralization of primary teeth according to restorative materials using quantitative light-induced fluorescence (QLF). A single bur hole was drilled on the each sound forty eight primary anterior teeth, and the specimens were divided into three groups. The cavity was restored with FiltekTM Z250(Group 1), F2000(Group 2), KetacTM N100(Group 3) following the manufacturer's instructions. The teeth were subjected to the demineralizing buffer for 3 days, and then subjected to a remineralizing buffer for 14 days. The change of mineral loss(ΔQ) according to the stages was evaluated by QLF and the following results were obtained: 1. When demineralization was done, ΔQ was increased as follows. : Group 1 (-110.79 ± 27.77) < Group 2 (-104.84 ± 28.95) < Group 3 (-90.16 ± 21.87) : Resistance to demineralization was statistically significant in Group 3. 2. There was a statistically significant increase in ΔQ of all groups since 1st day of remineralization 3. The rate of remineralization, Δ(ΔQ)/day, showed significant high value in each group on the 1st day then decreased rapidly. 4. There was no statistically significant difference in the degree of remineralization among restorative materials.

거대 난소 종양의 염전 1예

김미영,이해혁,유애리,박정희,이임순,정수호,고은석,레앙소팥,배동한,김태희,이권해 순천향의학연구소 2008 Journal of Soonchunhyang Medical Science Vol.14 No.1

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인후두부 이물감을 호소하는 환자에서의 기질적 요인 및 심인성 요인의 중요성

손영익,권중근,이풍렬,이화영,유범희,김지혜 대한이비인후과학회 1998 대한이비인후과학회지 두경부외과학 Vol.41 No.3

전위된 상악 견치 및 하악 측절치의 치험례

권해숙,현홍근,김영재,김정욱,장기택,김종철,한세현,이상훈 大韓小兒齒科學會 2009 大韓小兒齒科學會誌 Vol.36 No.4

Tooth transposition is an anomaly of eruption characterized by the interchanged positions of two adjacent teeth, which is divided into complete and incomplete transposition. There are three common approaches for treating transposition: aligning the involved teeth in their transposed positions, moving them to their correct anatomic position in the arch and extracting one of the transposed teeth. Considerations in treatment plans are esthetic, function, risk of jeopardizing the roots and damaging the supporting structures, position of the root apex, developmental stages of teeth and expected compliance. The presented case reports described one maxillary canine-the first premolar transposition and two mandibular lateral incisor-canine transpositions. The former transposed teeth were arranged in their transposed position, and the latter transposed teeth were rearranged into their normal position. 치아전위란 인접한 두 치아의 위치가 서로 바뀐 치아 위치 이상을 말하며, 치관과 치근의 위치에 따라 완전전위와 불완전전위로 나눌 수 있다. 하악보다는 상악에 편측성으로 호발하며, 특히 상악 견치에서 자주 발생한다. 전위는 발견 시기와 전위된 양상에 따라 치료방법이 달라질 수 있다. 본 증례는 상악 견치와 제1소구치 간의 전위가 일어난 10세 7개월의 환아와 하악 측절치와 견치 간의 전위가 일어난 8세 11개월 환아와 8세 9개월 환아의 교정치료에 대한 것으로 양호한 치료 결과를 얻었고, 증례 별로 치료방법의 차이점에 관한 고찰을 하였기에 이를 보고하는 바이다.

다공질 Si의 열적 안정성 연구

권영해,조훈영,홍치유 동국대학교 자연과학연구원 1995 자연과학연구 논문집 Vol.15 No.-

The oxidation and pressure effects of electrochemically etched porous Si have been investigated by photoluminescence(PL) and Raman spectroscopy. The porous Si sample was etched with a current density of 50mA/㎠ for 20 min, and shows a PL signal at 710 nm and a Raman peak at 517 cm. Rapid-thermal-annealing of the as-etched sample at 400℃ shows a rapid drop in the PL intensity. On the other hand, the intensity of the rapid-thermal-oxidized sample remains constant in the temperature range from 600℃ to 800℃. The Raman signal of the oxidized sample also showed thermal stability. The reverse leakage current of the oxidized porous Si was reduced to 100 times in comparision to that of as-grown porous Si. The PL peak position of the oxidized porous Si shows the shifts to 705 nm and the Raman peak shifts to a higher energy, closer that of the bulk polycrystalline Si. This can be explained in terms of the stress on the Si columnar structure. The initial tensile stress induced by the etching process is reduced by the compressive stres caused by the formation of oxides (SiO₂) in the gaps. It is supposed that this can cause the blue shift in the PL spectrum and the recovery of the Raman peak position.

이온 플레이팅법으로 제조한 TiN 박막의 미세구조

권순영,김민호,이해석,손창헌,김규호 嶺南大學校 工業技術硏究所 1997 工業技術硏究所論文集 Vol.25 No.1

Hard coating의 일종인 TiN 피막을 PVD 법으로 제조할 경우, 이온 충돌 양상을 조절할 수 있는 기판 Bias와 질소 분압 등이 미세 구조와 피막 특성에 많은 영향을 미치는 것으로 알려지고 있다. 본 실험에서는 Ion plating에 의한 TiN 피막 제조에서 기판 바이어스 전압과 질소 분압을 변화시키면서 TiN 피막을 제조하고, 미세 구조를 조사하였다. 공정 변수에 관계없이 얻어진 모든 피막은 δ-TiN 단일상이었다. 질소 분압이 높아짐에 따라 우선배향은 (111)면에서 (200)면으로 바뀌었으며, (111)회절상과 (222) 회절상의 반가폭의 비는 감소하였다. 그리고 결정의 크기는 감소하는 거동을 보였으며 피막의 격자 상수는 증가하는 경향을 보였다. 기판 바이어스 변화에 대해서는 전압이 증가함에 따라 (111) 회절상의 반가폭은 -100V 가지 증가하다 그 이상에서는 다시 감소하였으며, 그 때 결정이 크기는 증가하는 경향을 보였다. 피막의 격자 상수는 기판 바이어스가 증가함에 따라 150V까지 증가하다 그 이상에서는 다시 감소하였다. The action of ionized particles has to be controlled properly in ion plating method, because the action of ionized particles has an effect on the microstructure of the thin film. In this pointview, we investigated microstructure of TiN thin film that was deposited with variables of N₂partial pressure is increased, the prefered orientation was changed(1110 plane to (200) plane, the ratio of FWHM of (222) to FWHM of (111)was decreased, grain size was decrease and lattice parameter was increased. As bias voltage was increased, the FWHM of (111) peak was increased to-100V, and then decreased with the grain size was increased. Lattice parameter of film was increased to-150V, and then decreased

기업의 지배구조가 경영성과에 미치는 영향

권해익,이준영 啓明專門大學 産業開發硏究所 1999 啓明硏究論叢 Vol.17 No.1

본 연구는 지배구조가 경영성과에 어떤 영향을 미치는지를 측정하고자 한다. 종속변수로 토빈 Q를 이용하였고 독립변수로는 대주주인 1인 지분을, 이사회의 규모, 외국인 지분을, 주거래은행 차입금 비율등을 이용하였다. 연구결과 대주주1인 지분율과 외국인 지분율 그리고 주거래은행 차입금비율은 토빈의 Q와 양의 관계를 가지는 반면 이사회의 규모는 음의 관계를 나타내었다. 특히 외국인 지분율은 강한 양의 관계를 보임으로써 외국인이 상대적으로 경영성과가 우수한 기업에 많이 투자하고 있다는 것을 발견할 수 있었다. This paper examines the impact of corporate governance on financial performance. We used Tobin's Q as dependent variable and large shareholder ratio, board size, foreigner's shareholder ratio and main bank debt ratio as independent variables. The Empirical tests indicate that large shareholder ratio, foreigner's shareholder ratio and main bank debt ratio have positive relations to Tobin's Q, but board size has negative relation to Tobin's Q. Especially, foreigner's shareholder has strong positive relation to Tobin's Q, so we find foreigners invest their fund to relatively better corporations.

유기과산화물의 합성방법에 관한 고찰

권순경,박영남,박해선 德成女子大學校 藥學硏究所 2004 藥學論文誌 Vol.15 No.1

Compounds with an oxygen-oxygen single bond, are called peroxides, which undergo homolysis readily by heating or irradiation with light, because the oxygen-oxygen bond is weak. The formed products are radicals, which are short-lived and highly reactive. This property is used as initiator in radical chain reaction such as halogenation and many kinds of polymerization. Peroxides are one of the important oxidants and initiators. In this paper synthetic methods of peroxides and mechanisms are reviewed.

체중감량이 유도선수의 Renin, 면역기능 및 유·무산소 운동능력에 미치는 영향

권영우,전승훈,김진해,민경선,민진아 한국스포츠리서치 2001 한국 스포츠 리서치 Vol.12 No.4

The purpose of this study was to investigate the effect of short terms weight reduction period on body composition and body fluid. Seven Judo athletes (21±1.21 yrs) were matched and randomly placed. Body weight reduction period consists of 7 day. Each groups reduced body weight by 3%(2th day from pre weight reduction), 5%(4th day from pre weight reduction, 7%(7th day) and investigated the recovery period on 3 hour after breakfast, lunch, and 1day, 2day after 7% body reduction. Weight reduction reduced weight during weight reduction period then returned to baseline during recovery(p<.05) and decreased LBM, electrolyte, and immune function and then increased in recovery period to baseline. In conclusion, weight reduction of Judo athletes caused the change biological variable and performance and STWR may detrimental effects body' homeostasis.