상아질 접착에서 collagenase와 esterase가 미세인장결합강도에 미치는 영향

정영정,현홍근,김영재,김정욱,이상훈,김종철,한세현,장기택 대한소아치과학회 2007 大韓小兒齒科學會誌 Vol.34 No.2

상아질-레진 접착강도에 대한 collagenase와 esterase의 영향을 살펴보기 위해, 소구치의 교합면 상아질에 Single Bond 2와 Clearfil SE Bond로 접착을 시행하고 미세 시편을 제작하여 PBS, collagenase 용액, esterase 용액에 4주간 보관한 후 미세인장결합강도를 측정, 비교하여 다음과 같은 결론을 얻었다. 1. 모든 보관 용액에서 Single Bond 2의 미세인장결합강도는 Clearfil SE Bond보다 유의하게 낮았다(p<0.05). 2. Single Bond 2의 미세인장결합강도는 collagenase군이 PBS군, esterase군보다 낮았다(p>0.05). 3. Clearfil SE Bond의 미세인장결합강도는 esterase군이 PBS군에 비해 낮았으나(p>0.05), collagenase군보다는 높았다(p>0.05). Collagenase군은 PBS군에 비해 유의하게 낮은 미세인장결합강도를 보였다(p<0.05). The purpose of this study was to evaluate the effect of collagenase and esterase on the microtensile bond strength (μTBS) in dentin bonding. After resin composites were bonded to occlusal dentin, μTBS specimens were formed and stored in PBS, collagenase, or esterase solution. After 4-week storage, μTBS was determined and, the results were as follows: 1. μTBS values of Single Bond 2 were lower than those of Clearfil SE Bond for all storage medium (p<0.05). 2. In single Bond 2 group, collagenase solution lowered bond strength more than PBS and esterase solution (p>0.05). 3. In Clearfil SE Bond group, esterase solution lowered bond strength more than PBS(p>0.05). Collagenase solution lowered bond strength more than esterase solution(p>0.05) and PBS(p<0.05).

심실 중격 결손에 의한 감염성 심내막염 환자의 치과치료

양정현,현홍근,김영재,김정욱,장기택,이상훈,한세현,김종철 대한소아치과학회 2007 大韓小兒齒科學會誌 Vol.34 No.3

김치에서 분리한 Lactobacillus sp. JC-7과 Lactobacillus acidophilus 88간의 Electrofusion 최적조건 설정

조영배,최현정,백형석,전홍기 부산대학교 유전공학연구소 1997 분자생물학 연구보 Vol.13 No.-

김치 발효 숙성기간을 연장하고 신선도를 오랫동안 유지 할 수 있는 김치발효 starter의 개발을 목적으로 최적숙성기에 있는 김치로부터 bacteriocin생성능이 없는 유산균을 분리하여 동정하였으며, bacteriocin생성능이 우수한 L.acidophilus 88을 융합시키기 위해 electrofusion에 대한 최적 조건을 검토하였다. 분리균주는 Lactobacillus속으로 동정되어 Lactobacillus sp. JC-7이라 명명하였다. Electrofusion에 의해 생성된 융합주를 식별하기 위해 streptomycin(2.5㎎/ml)에 내성을 나타내는 Lactobacillus sp. JC-7변이주와 kanamycin(600㎍/ml)에 내성을 나타내는 L.acidophilus 88변이주를 분리하였다. Electrofusion을 100V/㎝, 120msec(72ohms,1670 capacitance) 에서 수행했을 때 융합효율이 가장 양호하였으며 전기장의 세기와 시간이 중가할수록 융합 효율이 현저히 감소하였다. 2가 양이온은 농도가 중가할수록 대체적으로 융합효율을 감소시키는 경향을 나타내었으나 1mM MGCl_2에서는 대조군에 비해 융합효율이 약간 증가하였다. PEG매개에 의한 융합법의 융합효율을 비교한 결과, 융합효율은 chemical fusion<electrofusion<electrofusion+20% PEG순을 나타내었다. Evaluation of Optimum Conditions for the Electrofusion between Lactobacillus sp. JC-7 Isolated from Kimchi and Lactobacillus acidophilus 88. Young-Bae Jo, Hyun-Jung Choi, Hyung-Suk Baik and Hong-Ki Jun*. Department of Microbiology, Pusan National University, Pusan 609-735,Korea-A lactic acid bacterium was isolated from kimchi. The isolated strain was identified as the genus Lactobacillus thrugh its morphological characteristics and named as Lactobacillus sp. JC-7. The optimum conditions for the electrofusion between streptomycin(2.5㎎/ml)resistant mutant of Lactobacillus acidophilus 88 and kanamycin(600㎍/ml) resistant mutant Lactobacillus sp. JC-7 were evaluated. The highest number of fusants were obtained at a capacitance value of 120msec(1670㎌), a field strength of 100V/㎝,and a pulse controller setting of 72Ω. The potimum pH of elecroporation buffer was 7.5 and the concentration of divalent cation was 1mM MG^2+. Electrofusants were efficiently obtained by addition 20% polyethylene glycol to electroporation buffer. The yield of fusion was better than that of using polyethylene glycol mediated chemical induction.

농촌지역 노인들의 우울증상에 관련된 요인들의 특성

송미숙,전기홍,송현종,김정은,박승구,신상건,이동훈,정성현,최연주,최완철,최민규,황재철,홍지만 아주대학교 1997 아주의학 Vol.2 No.2

This study was performed to identify risk factors for depression among the elderly in a rural area. A survey was done for the elderly living in Gosam-myenn, Ansung-kun during the period of July 28, 1997 and July 30, 1997. Demographic and sodoeconornic characteristics, and functional and health Status were assessed using a structured questionnaire, and the level of depression was measured by GDS score. The data obtained were analyzed by frequencies, percentage, t-test, ANOVA, and multiple regression, and the results were as follows: 1. The total sample consisted of 133 elderly. Of them, 47 elderly (35.4%) showed significant depressive Symptoms. 2. The GDS score was the highest for the group over 85 years of age (p < 0.05). Those living alone or widowed showed lower GDS score than those living with someone or married (p < 0.05). 3. The GDS score was the highest in the absolutely dependent group, followed by the partially dependent group, and the independent group (p < 0.01). The elderly who perceived their health Status as excellent showed the lowest GDS score. In contrast, those who had more than five chronic diseases showed the highest GDS score. 4. The elderly receiving financial and emotional support from their family or friends showed lower GDS score compared to those without any support. 5. The economically dependent group showed higher GDS score than that of independent group. 6. The elderly who involved in leisure activities showed lower GDS score than those without any involvement. 7. In terms of risk factors for depression, we found that perceived health Status, subjective economic Status, leisure activities, living arrangement and financial support were inversely associated with GDS score, whereas labor support was positively associated with GDS score. Based upon the above findings, this study suggests that these risk factors for depression in the elderly should be taken into consideration for a comprehensive mental health program for the elderly living in the rural area.

슬래브의 영향을 고려한 보-기둥 접합부에서 보의 인장철근 배치에 관한 수치해석적 연구

洪起燮,朴正鉉 홍익대학교환경개발연구원 2000 환경개발연구논문집 Vol.5 No.-

Due to the congestion of the reinforcement, it is difficult to arrange properly 2-layer tension reinforcement at the beam-column joint. In ACI and Eurocode, it is recommended to distribute the tension reinforcement within the effective width of flange uniformly to control flexural cracks. In this study, it is conducted a nonlinear analysis of beam-to-column joints using ANSYS to evaluate the ultimate strength and the general behavior of the joints. It is compare to arrange 2-layer tension reinforcement within rectangular section with single-layered tension reinforcement at the beam flange. Based on the results of this analysis, the following conclusion can be drawn : 1. The load-displacement curves of the models were very similar to below 3㎜. That is, the ultimate strength of the model is no difference between arranging 2-layer tension reinforcement within rectangular section and single-layered tension reinforcement at the beam flange at the below 85% of ultimate strength. 2. For the single-layered tension reinforcement it is recommended to provide additional reinforcement at the beam-column joint to attain ultimate load capacity equal to the 2-layered case.

피로를 유발하는 등속성 수축시와 회복기 혈중젖산 및 외측광근의 EMG Power Specturm 변화

정정진,조현철,김기진,윤성원,오수일,홍관이,손태열 龍仁大學校 體育科學硏究所 1991 體育科學硏究論叢 Vol.1 No.1

To examine the change of blood lactate concentration, EMG power spectrum, and Torque during fatiguing isokinetic contraction and recovery phrase, 6 sprinters performed maximal isokinetic knee extension at angular velocity of 3.14 rad.sec??(180°sec??) to 75% decreasing point (25%PT) using CybexⅡ system. In exercise phase, there was significant correlation between the decrement of peak EMG and median frequency and that of torque, and decrement of torque was greater than that of EMG . In recovery phase, EMG was restituded as normal value rapidly in a minute, but torque was restituded more slowly, and blood lactate concentration increased gradually from 50%PT to 3 minute after recovery. As a result of this study, it is suggested that muscle fatique due to decreasing of metabolic substrate and accumulation of metabolic products in peripheral site of muscle, and that inhibitory factors act neuromuscular junction in the end of exercise from rapid restitution of EMG in recovery phase.

In situ hybridization과 염색체 미세해부에 의한 특정 염색체 띠에 대한 유전자 발굴

홍기정,김현수,전용혁,김현,박선화 고려대학교 의과대학 1996 고려대 의대 잡지 Vol.33 No.1

Recently surmountable amounts of genes are being cloned but it is hard to define the chromosomal location and functions of these genes. In this study, a new technique was developed for cloning genes expressed in the developing human brain with confirmed chromosomal location. The mRNAs were extracted from 18 week old human fetal brain, cDNAs were made by reverse transcription from these mRNAs and Uni-amp cDNAs having Uni-amp adapters a t both ends were made for subsequent PCR. To observe the distribution of the Uni-amp cDNAs on the chromosome, fluorescent in situ hybridization was performed with biotin labeled Uni-amp cDNAs. Among the chromosome bands showing strong hybridization with the cDNAs, lq21, lq25, lq32 and lq42 were microdissected from the chromosome hybridized with unlabeled Uni-amp cDNAs and amplified by PCR with Uni-amp primers. These amplified cDNA fragments were subcloned to plasmid vectors and the nucleic acid sequences were analysed. As a result 18 different clones were confirmed the chromosomal localization. They were categorized as 4 clones of well characterized genes, 3 clones showing low homology with known genes, 5 clones of simply registered uncharacterized human cDNAs, and 6 clones of unknown genes. The evidence suggests that the technique is very useful to clone the genes that express in the developing human brain, with confirmed chromosomal location. In addition, this cloning technique can be used to discover the new genes related with neuronal development in combination with functional screening method.

정신병적 증상이 동반된 기면병 1예

홍승철,송정민,정종현,권용실,한진희,이성필 大韓神經精神醫學會 2003 신경정신의학 Vol.42 No.5

Narcolepsy is a sleep disorder characterized by excessive daytime sleepiness, cataplexy, sleep paralysis, hypnagogic hallucinations and disrupted nocturnal sleep. We report a patient with a diagnosis of schizophrenia who was subsequently diagnosed as narcolepsy. A case of a 22-year-old woman with concomitant narcolepsy and psychotic symptoms was discussed from a perspective of the diagnosis and therapeutic challenges, particularly on pharmcological treatment dealing with issues raised by their coexistence.

관광호텔의 리더쉽 유형이 조직유효성에 미치는 영향

홍경욱 ; 박진영 ; 이현정 김천대학교 2000 김천대학교 논문집 Vol.21 No.-

The Leadership is very important for organizational behavior in every organization. Excellent leadership guide an organization to achievement. The leadership is more important in hotel organizations because which are highly dependent on human resources compare with other organizations. The Purpose of this research is to examine what influence leader-ship has on organizational performance. The variables of leadership are initiation structure leadership and consideration leadership. And the factors of organizational effective-ness are job satisfaction and job commitment. The results of this study revealed the followings : First, the initiation structure leadership and consideration leader-ship both effect on job satisfaction and the consideration leadership is more influence than initiation structure leadership. Second, the consideration leadership has positive effect on organi-zational commitment, but initiation structure leadership has not positive. This results means employees recognize more important the consideration leadership consist of friendship. confidence and respect.

유전자 알고리즘을 이용한 이동로봇의 지능제어

정동연,김홍래,한성현 한국공작기계학회 2004 한국공작기계학회 추계학술대회논문집 Vol.2004 No.-

This paper proposed trajectory tracking control of Mobile Robot. Trajectory tracking control scheme are Real coding Genetic-Algorithm and Back-propergation Algorithm. Control scheme ability experience proposed simulation.