전형적인 DISIDA scan 소견의 Rotor 증후군 1예

황의태,염동한,권지혜,임종주,최창수,김태현,김학철 圓光大學校 醫科學硏究所 2008 圓光醫科學 Vol.23 No.2

만성의 비용혈성 직접형 고빌리루빈혈증은 Rotor 증후군과 Dubin-Johnson 증후군의 특징적인 소견으로, Rotor 증후군은 드문 양성 유전성 질환이며, Dubin-Johnson 증후군과 감별을 필요로 한다. 본 저자들은 황달을 주소로 내원한 26세 남자 환자에서 고빌리루빈혈증에 대한 검사를 시행하여 담도폐쇄 소견없이 간담도 스캔상 전형적인 Rotor 증후군의 소견 즉, 강한 심장 배후방사능이 지속되면서, 간담도계의 조영은 지연 촬영에서도 관찰되지 않으며 신장으로의 배설이 계속 관찰되는 특징적인 소견과 정상 간조직 검사 결과로 Rotor 증후군으로 진단한 1예를 경험하였기에 문헌 고찰과 함께 보고하는 바이다. Chronic nonhemolytic conjugated hyperbilirubinemia characterizes both Rotor and Dubin-Johnson syndromes. Rotor syndrome is a rare, benign familial disorder and needs to be differentiated from Dubin-Johnson syndrome. Cholescintigraphy is a simple and informative procedure for the diagnosis, which can differentiate Rotor syndrome from Dubin-Johnson syndrome. A 26-year-old man was admitted due to asymptomatic persistent jaundice. Physical examination revealed icteric sclera without hepatosplenomegaly. Laboratory findings showed increased serum bilirubin with direct bilirubinemia. Markedly decreased hepatic uptake and poor visualization of the gallbladder and biliary tract were shown in ^(99m)Tc-DISIDA scan. Histology of the liver showed no diagnostic abnormality without pigmentation. But, we report a case of Rotor syndrome that showed characteristic cholescintigraphic findings with normal urinary total coproporphyrin excretion.

치아크기 계측오차에 관한 연구

심은주,황현식,문재동 대한치과교정학회 1999 대한치과교정학회지 Vol.29 No.4

본 연구는 석고모형 분석 중 치아크기 측정시 발생할 수 있는 오차를 줄이고 측정의 재현도와 정확성을 향상시키는데 도움이 될 수 있는 방안을 모색하고자 시행되었다. 치아밀집 치열 특징을 지닌 상하악 20조의 석고모형을 대상으로하여, 5명의 조사자가 각 치아의 근원심 폭경을 디지털 버니어 캘리퍼스를 사용하여 2주 간격으로 3회 측정하여 실험측정치를 얻은 다음, 측정에 이용된 석고모형을 근원심 접촉점 부위에서 개개 치아로 분리한 후, 마이크로미터를 이용하여 측정한 표준치와 비교 · 분석하여 다음과 같은 결과를 얻었다. 1. 3회 측정에 따른 재현도는 조사지별 치아별로 큰 차이를 나타내지 않았다. 2. 표준치와 비교한 계측오차는 조사자별 또는 치아별로 차이를 보였다. 3. 표준치와의 오차는 전치에서 구치로 갈수록 증가하여 제1대구치에서 가장 큰 차이를 나타내었다. 4. 표준치와 비교시 전반적으로 작게 측정하는 경향을 보였으며 이에 대한 치아별,조사자별 차이가 두드러졌다. 5. 전반적인 오차 발생 정도는 치아밀집 정도와 유의한 상관성을 보이지 않았다. 이상의 결과는 교정증례 분석시 치아크기 계측오차 발생 가능성의 고려가 필요함 을 시사하였다. Precise and accurate measuring of tooth size is essential procedure in orthodontic diagnosis. The purpose of this study was to evaluate the reproducibility and accuracy of tooth size measurements with regard to tooth and investigator. Five investigators measured the size of one side of teeth, from central incisor to first molar, on 20 sets of casts that show a moderate degree of crowding. Mesio-distal width was measured with digital vernier calipers in each tooth and this procedure was repeated three times at two weeks interval. To obtain a standard measurement for each tooth, dental casts were cut into individual tooth, and its width was measured with micrometer. The difference between the measurement from dental cast and the standard measurement was defined as the measurement error. Through various statistical analyses, following results were obtained. 1. The reproducibility did not show significant differences with regard to tooth or investigator. 2. The measurement error showed some difference with regard to tooth and investigator. 3. The magnitude of the measurement error showed increasing tendency from anterior to posterior teeth with maximum value in the first molar. 4. While the measurements obtained on study casts generally showed smaller number compared to standard measurements, the direction of the difference showed variability accrording to tooth or investigator. 5. The measurement errors did not show significant correlations with the degree of crowding. The results of the present study indicate that the possibility of tooth size measurement error should be taken into consideration when diagnosing an orthodontic case.

전기도금을 이용한 스테인레스스틸 각형 선재의 굵기 증가 후 물성 변화

이정석,황현식,최광철,문재동 전남대학교 치의학연구소 2002 구강과학 Vol.14 No.1

The purpose of this study was to evaluate clinical applications of electroplating method through investigation of the physical properties of orthodontic rectangular wires according to varying their cross section. For the study, it was accomplished to electroplate the 0.016-inched orthodontic rectangular stainless steel wire. The cross section of stainless steel orthodontic rectangular wire increased from 0.016 X 0.016 inch to 0.017 X 0.017 inch by electroplating. The wire was heat treated to improve an adhesion between the wire and electroplated metal. A three-point bending test and torsion test were conduced in order to compare physical properties among three wire groups; 0.016 X 0.016 wires(group 016P) and 0.017 X 0.017 wires(group 017). Through the investigations of each wire group, following results were obtained. 1. At three-point bending test, the group 016P showed higher tendency in the degree of stiffness, yield strength and ultimate tensile strength than the group 016. Stiffness and ultimate tensile strength showed statistically significant differences between two groups at three-point bending test(p<0.05). 2. Stiffness, yield strength, and ultimate tensile strength of the group 016P showed lower tendency than those of the group 017. Stiffness showed statistically significant differences between two groups at three-point bending test(p<0.05). 3. Torque/twist rate, yield torsional moment, and ultimate torsional moment of the group 016P showed higher tendency than those of the group 016. All measurements showed statistically significant differences between two groups after torsion test(p<0.05). 4. Torque/twist rate, yield torsional moment, and ultimate torsional moment of the group 016P showed lower tendency than those of the group 017. Yield torsional moment, and ultimate torsional moment showed statistically significant differences between two groups after torsion test(p<0.05). Xylitol is a 5-carbons carbohydrate, which can be replaced with sucrose for preventing caries. The replication of Streptococcus mutans and its formation of artificial plaque were studied in the media containing xylitol. The combined effect of xylitol and other carbohydrates on Streptococcus mutans was also studied. The replication of Streptococcus mutans was inhibited according to the increased concentration of xylitol. Streptococcus mutans replicated at the initial stage of incubation in the media contaning glucose, fructose or lactose, while replication from the beginning of incubation in the media containing fructose as combining with xylitol. The formation of artificial plaque by Streptococcus mutans was significantly reduced in the media containing with xylitol and fructose. These results indicated that the replication of Streptococcus mutans was inhibited according to the increased concentration of xylitol, and the formation of artificial plaque by Streptococcus mutans was significantly inhibited in the media containing xylitol and fructose.

제2형 당뇨병 환자에서 적극적 환자 교육이 혈당조절에 미치는 효과

이윤욱,황원선,최선정,이동훈,김도현,이은희,홍은경,노혜림,정윤석,이관우,김현만 대한내분비학회 2003 Endocrinology and metabolism Vol.18 No.1

연구배경: 현재까지의 당뇨병 교육에 대한 노력은 제한되었으며, 연구 결과를 보면 식사 조절 교육과 체중 조절 프로그램을 수행한 환자들 중 적극적이고 기간이 긴 교육을 받은 경우, 성공적 결과가 나타남을 알 수 있었다. 자가관리나 체중감량 등의 당뇨병 치료의 중요한 목표는 적극적이고 긴 기간의 교육 없이는 시행되기 어렵다. 본 연구에서는 외래에서 당뇨병 환자를 대상으로 시행할 수 있는 행동 및 식사 교육 등의 적극적 교육 프로그램을 개발하여 제2형 당뇨병 환자들을 대상으로 이들에게 식사 조절 방법에 대한 목표설정과 문제에 직면하였을 때의 해결 방법 등을 교육해서 궁극적으로는 적극적 자아관리에 연결될 수 있도록 도와주는 것을 목적으로 기존의 통상적 교육과 보다 적극적인 교육이 당뇨병 환자의 혈당 조절에 어떠한 영향을 미치는지에 대해 알아보기 위해 다음과 같은 연구를 시행하였다. 방법: 본 연구는 아주대학교 병원 내분비 대사 내과를 처음으로 방문하여 치료받았던 58명의 제2형 당뇨병 환자를 대상으로 하였다. 내원 환자들을 무작위하게 추출하여 진찰권 번호 끝자리에 따라 홀수는 통상적 교육군(conventional education group, CE)과 짝수는 적극적 교육군(intensive education group, IE)으로 나누어 교육하고, 3개월후에 교육의 효과를 평가하였다. 결과: 1) 연구 대상자들의 교육 전과 후의 공복혈당, 식후2시간 혈당 및 HbA_lc 치는 IE군과 CE군 모두 각 그룹 내에서, 유의적으로 감소하였다(p<0.05). IE군에서는 공복혈당이 12.4nmol/L에서 7.7nmol/L로, 식후2시간 혈당이 20.3nmol/L에서 10.9nmol/L으로, HbA_lc치가 9.4%에서 7.0%로 모두 교육 전에 비하여, 교육 후에 감소(p<0.05)하였고, CE군도 공복혈당은 10.9nmol/L에서 9.4nmol/L로, 식후2시간 혈당은 17.1nmol/L에서 14.6nmol/L으로 HbA_lc가 8.5%에서 7.3%으로 모두 교육 후에 감소하였다(p<0.05). 또한, 교육 전에 비하여 교육 후에 공복 혈당 및 HbA_lc치가 감소하는 정도는 IE군에서의 감소가 CE군에 비해 더 현저하였다Op<0.05). 2) 식사에 대한 태도는 3부분으로 나누어 식사에 대한 규칙성, 식사 내용의 균형성, 식사에 대한 태도 등으로 나누어 각각의 점수 및 총점을 비교하였으며 교육 전에 비해 교육 후에 연구 대상자들의 식태도가 향상되었음을 알 수 있었다. 두 그룹간의 차이를 분석한 결과 식사의 균형성 항목에서와 총점에서 유의적으로 두 그룹의 차이를 보여서 IE군에 CE군에 비해 식사의 균형성 측면이 향상되었고, 전체적인 식태도가 좋아졌음을 알 수 있었다(p<0.05). 결론: 비교적 긴 기간은 아니지만 적극적 교육을 받은 당뇨병 환자들이 통상적 교육을 받은 군보다 혈당 및 HbA_lc, 식태도 점수등의 수치의 호전뿐만 아니라 당뇨병 환자의 삶에서 중요한 부분을 차지하는 식사요법 관리 부분에 있어 향상됨을 알 수 있었다. Background: To this date, efforts to develop effective methods for the education of diabetic patients have been limited. The important goal of self-management and weight control for diabetic treatment can not be attained without long and intensive period of education. This study was undertaken to assess the effectiveness of an intensive educational program, of behavior and diet control, which was carried out on subjects with type 2 diabetes, on and out-patient basis. we compared the effectiveness of an intensive education programme with that of a conventional education programme for the self-management of type 2 diabetic patients. Methods: Subjects with type 2 diabetes were randomly selected, and allocated to one of two groups. One group received a conventional education programme of self-management(the CE group), and the second group received an intensive education progammes for three months, after which the effectiveness of the programmes were evaluate. Results: 1) The levels of fasting blood sugar(FBS), postprandial 2 hour blood sugar(PP2h) and HbA1c were significantly lowered in both groups following the intervention(p<0.05). In the IE group, the FBS declined from 12.4nmol/L to 7.7nmol/L, PP2h declined from 20.3nmol/L to 10.9nmol/L, and the HbA_lc showed a similar decline from 9.4 to 7.0% after intervention(p<0.05). In the Ce group, the FBS declined from 10.9 to 9.4nmol/l, the PP2h decreased from 17.1 to 14.6nmol/l, and the HbA_lc also decreased from 8.5 to 7.3% after intervention(p<0.05). The decrease in the FBS and HbA_lc following the educational intervention was more pronounced in the IE group than the CE group(p<0.05). 2) The effectiveness of the education programmes in promoting appropriate dietary behavior in the diabetic subjects was assessed by a scoring system in three parts: a regularity score, a balance score and an attitude score. From a comparative study of the three scores, the patients attitudes were observed to be much improved in both the groups following the intervention compared to before the programmes, but the balance and total scores were significantly higher in the IE group than the CE group(p<0.05). Conclusion: We can conclude that the intensive diabetic education programme is more effective than a conventional programme, not only in improving the patients' levels of glucose, HbA_lc, and dietary score, but also the diabetic patients self-control abilities, promoting behavioral change, and prompting problem solving capabilities in respect to the everyday problems that they have to face throughout their lives(J Kor Soc Endocrinol 18:63∼72, 2003).

서울의 Penicillinase Producing Neisseria gonorrhoeae 발생빈도(1997)

김재홍,문득곤,김정수,김용준,임동진,박상훈,김희성,이민수,송기훈,김갑형,김형석,성소영,이인섭,김석우,황지환,조창근,김경문,부태성 대한화학요법학회 2000 대한화학요법학회지 Vol.18 No.3

Background : In recent years, gonorrhea has been pandemic and remains one of the most common STDs in the world, especially in developing countries. Objective & Methods : For the detection of a more effective therapeutic regimen and assessing the prevalence of PPNG, we have been trying to study the patients who have visited the Venereal Disease Clinic of Choong-Ku Public Health Center in Seoul since 1980 by means of the chromogenic cephalosporin method. Results : In 1997. 99 strains of N. gonorrhoeae were isolated, among which 45(45.5%) were PPNG. Conclusion : The prevalence of PPNG in Seoul, which had been decreased to 39% in 1996 after a peak of 74.3% in 1993, is increased to 45.5% in 1997.

Genome-Wide Random Mutagenesis System using Proofreading-Deficient DNA Polymerase δ in the Methylotrophic Yeast Hansenula polymorpha

Dong Hyeon HWANG,Sang-Yoon KIM,Doo-Byoung OH,Ohsuk KWON 한국생물공학회 2013 한국생물공학회 학술대회 Vol.2013 No.4

Comparison of Three Plating Media for Enumerative Detection of Clostridium perfringens in Various Foods

Dong Hyeon Kim,Yun Gyeong Kim,Jung Whan Chon,Ji Yeon Hyeon,In Gyun Hwang,Hyo Sun Kwak,Sang Hyeon Yoon,Kun Ho Seo 대한수의학회 2011 대한수의학회 학술대회발표집 Vol.2011 No.-

Characterization of the Phosphorelay Protein Ypd1 in Two-Component Signaling System of the Methylotrophic Yeast Hansenula polymorpha

Dong Hyeon HWANG,Eun Hye KIM,Doo-Byoung OH,Ohsuk KWON 한국생물공학회 2013 한국생물공학회 학술대회 Vol.2013 No.4

제어방법에 따른 비 반전 벅-부스트 컨버터 효율비교

황동현(Dong-Hyeon Hwang),이우철(Woo-Cheol Lee) 한국조명·전기설비학회 2017 조명·전기설비학회논문지 Vol.31 No.1

A non-inverting buck-boost converter is used to keep the output voltage constant if the range of variation of the input voltage is lower or higher than the desired output voltage. It has a wide input/output voltage range and the output voltage is not inverted unlike a typical buck-boost converter. The non-inverting buck-boost converter is classified into continuous current mode, discontinuous current mode, and critical conduction mode depending on the inductor current. The losses of the switching device depends on the current modes and the efficiency of converter is also different. Therefore, in this paper, the converter is controlled by the fixed frequency method and the critical conduction mode method to compare the converter efficiency according to the current modes at low power. In each control method, the losses of the switching element were calculated and compared. Simulation and experiment were performed to confirm the calculated results.

부스트 컨버터를 이용한 태양전지 어레이 전역 최대전력점 추종 방법

황동현(Dong-Hyeon Hwang),이우철(Woo-Cheol Lee) 대한전기학회 2018 전기학회논문지 Vol.67 No.2

Since solar cells have non-linear voltage-current output characteristics, Photovoltaic systems require the Maximum Power Point Tracking(MPPT) function. For this reason, a large number of MPPT techniques have been studied. However, the conventional MPPT techniques may fail to track the maximum power point when partial shading occurs in the solar cell array due to its characteristics. Therefore, it is necessary to research the MPPT technique that can follow the maximum power point in the partial shadow condition. In this paper, the characteristics of solar cell arrays in partial shadowing are analyzed and the MPPT technique which can follow the maximum power point in partial shadow condition has been proposed. To validate the proposed MPPT method, simulation and experimentation results are provided.