요오드 식품의 섭취빈도 및 기타 갑상선질환 유발인자에 관한 연구

윤상연,이경혜,유봉옥 창원대학교 생화과학연구소 1999 생활과학연구 Vol.3 No.-

Frequency of iodine contained food intake and symptom, risk factors of thyroid disease and demographic informations were investigated form 30 patients with various thyroid disease (hypothyroidism simple goiter and thyroid adenoma) and 30 normal control subjects. All subjects were female. Iodine contained food intake was assessed using the food frequency questionnaires with portion sizes. Family history of thyroid disease, frequency of depression. nervousness and stress. experience of abortion, appetites were higher in patients group compared to normal control group. But intake of iodine contained food and food habits did not differ between two groups. In this study, therefore, personality, stress and family history of thyroid disease affected more cause of thyroid disease than the frequency of iodine contained food intake.

당뇨병 환자에서 혈장 Thrombin-Antithrombin Ⅲ 및 Plasmin-α_2-Plasmin Inhibitor 복합체의 임상적 의의

김경욱,김은숙,정상수,윤수지,박우일,이준희,남수연,안철우,문병수,김경래,차봉수,송영득,임승길,이현철,허갑범 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.25 No.5

연구배경:당뇨병 환자에서 혈액응고 및 섬유소용해 체계의 이상경향이 있어 그 결과로 여러 혈관합병증의 발생위험이 높다는 사실은 널리 알려져 있다. 그 기전은 아직 확실히 밝혀지지 않았으나, 고혈당으로 인한 혈장 단백질들의 비효소성 당화작용이나 산화성 스트레스로 인한 유리 라티칼 작용으로 응고항진이나 섬유소용해 활성의 저하를 유발하는 것으로 생각되고 있다. 최근 응고 및 용해인자와 그 억제자의 복합체들의 증가가 이 상태를 비교적 예민하게 반영한다고 알려져 있다. 방법:본 연구에서는 당뇨병 환자 101명과 정상 대조군 20명에서 혈장내 thrombin­antithrombin complex(TAT)와 plasmin­α₂­plasmin inhibitor complex(PIC)를 측정하여 비교하고, 당뇨병 환자에서 미세혈관 합병증과 대혈관합병증의 유무에 따른 차이와, 이미 혈관 질환의 위험인자로 알려져 있는 인자들간의 상관성을 알아보고자 하였다. 결과:1. 환자의 분포를 살펴보면 혈관합병증이 있는 군은 85명, 혈관합병증이 없는 군은 16명이었고, 평균연령은 각각 57.9±14.1세, 49.9±16.6세로 혈관 합병증이 있는 군에서 더 나이가 많았고, 체질량지수는 23.2±3.4㎏/㎡, 24.1±3.4㎏/㎡로 두 군간 유의한 차이는 없었다. 또 두 군간의 혈압 및 HbA1c, 공복혈당 및 인슐린과 C­peptide, 총 콜레스테롤, 중성지방, HDL­콜레스테롤, Lp⒜는 유의한 차이가 없었고, 미세혈관합병증이 있는 군에서 당뇨병의 유병기간이 길었다. 2. TAT 및 PIC의 농도는 정상 대조군에서는 2.8±1.2 ng/mL, 240.4±69.7 ng/mL이었고, 당뇨병 환자군에서는 9.5±22.6 ng/mL, 472.2±258.7 ng/mL이었다. TAT와 PIC 모두 당뇨병 환자군에서 정상 대조군에 비해 유의하게 증가되어 있었고(p<0.001), TAT/PIC ratio는 두 군간 차이가 없었다. 3. 당뇨병 환자의 혈관합병증에 따른 TAT 및 PIC, fibrinogen 농도는 합병증이 없는 군은 각각 4.1±2.4ng/mL, 362.2±272.0ng/mL, 322.7±102.4mg/mL으로 PIC와 fibrinogen의 증가를 보였으나, 연령을 보정한 후에는 통계학적 유의성은 없었다. 또 대혈관 합병증군에서는 각각 6.0±4.9 ng/mL, 507.4±321.6 ng/mL, 427.1±194.7 mg/dL이었으며 미세·대혈관 합병증군에서는 10.4±6.4 ng/mL, 484.8±269.7 ng/mL, 388.4±132.4 mg/dL으로 TAT의 증가를 보였으나 역시 연령을 보정한 후에는 통계학적 유의성은 없었다. 4. 미세혈관합병증군에서 HbA1c(>8%)가 높은 군의 PIC 농도가 유의하게 높았고(p=0.049), 대혈관합병증군에서 HbA1c(>8%)가 높은 군의 총 콜레스테롤 농도가 유의하게 높았다(p=0.042). 5. 총 당뇨병 환자군에서 PIC는 fibrinogen과 HbA1c와 양의 상관관계를, BMI와 음의 상관관계를 보였으며(r=0.47, 0.31,-0.25), 혈관 합병증이 없는 당뇨병 환자군에서만 TAT는 HbA1c와 양의 상관관계를 보였다(r=0.67). 결론:이상의 결과에서 혈장 TAT 및 PIC 농도는 당뇨병 환자에서 정상 대조군에 비해 의미있게 증가되어 있었고, 당뇨병 환자군에서는 연령의 증가와 유병기간이 혈액응고항진 및 용해의 장애에 큰 역할을 함을 알 수 있었으며, 총 당뇨병 환자군에 PIC와 HbA1c와 양의 상관관계를, BMI와 음의 상관관계를 보였으며 혈관 합병증이 없는 당뇨병 환자군에서만 TAT는 HbA1c와 양의 상관관계를 보였다. 따라서 당뇨병 환자에서 혈액응고 및 용해의 장애가 동반되어 있다고 볼 수 있으며, 혈장 TAT 및 PIC는 혈관합병증으로의 진행을 예측하는 지표로서 유용하리라 생각된다. 또 혈당조절정도와 상관성이 있으므로 혈당조절후에 추적검사를 시행하여 합병증의 예방이 가능한지 추후 연구가 필요하리라 생각된다. Background : Abnormality of coagulation and fibrinolystic system is known as a predisposing factor of vascular complication in diabetes. Although the pathogenesis is not well known, non-enzymatic glycation reaction and the increase in production of free radicals due to an increased oxidative stress may be linked to the hypercoagulibility and hypofibrinolytic activity. As indices of abnormality in coagulation and firinolysis in peripheral blood, plasma thrombin-antithrombin Ⅲ complex (TAT) and plasmin-α_2-plasmin inhibitor complex (PIC) were measured. The purpose of this study was to clarify whether hypercoagulability exists in diabetic patients with or without vascular complication. Methods : In our study, we measured plasma thrombin-antithrombin Ⅲ compelx (TAT) and plasmin-α_2-plasmin inhibit or complex (PIC) in 101 diabetic subjects and 20 controls. Comparing TAT and PIC levels in diabetic microvascular complication group, diabetic macrovascular complication group and controls, we examined correlation between risk factors associated with diabetic vascular complication. Results : 1. The group with diabetic vascular complication was older than group without complication. There was no significant difference in BMI, blood pressure, HbA_ic, blood sugar level, insulin, C-peptide, serum creatinine, total cholesterol, triglyceride, HDL-cholesterol, Lp (a) between two groups. The group with diabetic microvascular complication had longer duration of diabetes. 2. Concentration of TAT and PIC were 2.8±1.2 ng/ mL, 240.4±69.7 ng/ mL in controls and 9.5±22.6 ng/ mL, 472.2±258.7 ng/ mL in diabetic patients, respectively. TAT and PIC were significantly higher in diabetic patients than in control (p<0.001). But TAT/PIC ratio was no significant difference between two groups. 3. In diabetic patients, concentration of TAT and PIC and fibrinogen were respectively 4.1±2.4 ng/ mL, 362.2±272.0 ng/ mL, 322.7±102.4 mg/ dL in group without vascular complication and 5.3±4.1 ng/ mL, 529.5±258.7 ng/ mL, 374.9±106.2 mg/ dL in group with microvascular complication, which group had increase in PIC and Fibrinogen but no significance after correction of age. Concentration of TAT and PIC and Fibrinogen were 60.±4.9 ng/ mL, 507.4±321.6 ng/ mL, 427.1±194.7 mg/ dL in macrovascular complication, and 10.4±6.7 mg/ mL, 484.8±269.7 ng/ mL, 388.4±132.4 mg/ dL in combined vascular complication which group showed increase of TAT but also had no significant increase after correction of age. 4. In diabetic microvascular complication patients, group of high HbA_1c (>8%) (p=0.049) had significant high PIC concentration. In diabetic macrovascular complication patients, group of high HbA_1c (>8%) (p=0.042) had significant high total cholesterol concentration. 5. In all diabetic patients, PIC was positively correlated with fibrinogen and HbA_1c and negatively correlated BMI (r=0.47, 0.31, -0.25). Only in daibetic patients without angiopathy, TAT was positively correlated with HbA_1c (r=0.67). Conclusion : In this study, plasma TAT and PIC concentration significantly increased in diabetic patients compared with controls, and PIC was increased in group with microvascular complication, TAT were increased in group with combined micro macrovascular complication. However, there was no significance relationship existed when correctinf for age. PIC was correlated with HbA_1c. TAT was correlated with HbA_1c only in the group without angiopathy. Abnormality of coagulation and fibrinolysis were combined in diabetes, plasma TAT and PIC can be used as an index of vascular complication. Also we found the correlation with the degree of the blood glucose control. Therefore we need follow up study for the possibility of prevention of vascular complication after controlling the blood glucose to age-matched patients (J Kor Diaabetes Asso 25:354~363, 2001).

구속운동을 받는 외팔보의 혼돈진동

최봉문,류봉조,윤충섭,임경빈 大田産業大學校 2000 한밭대학교 논문집 Vol.17 No.1

When the motion of vibrating structure is restrained by the adjacent objects, its vibration frequencies and mode shapes are changed. In general, the vibration characteristics of the system becomes unpredictable. Although the importance of the study on this type of vibration model increases in many engineering areas, most studies conducted to date were focused to the theoretical study on dynamic responses of the structure with stops, including a few experimental works. Specially, the study on the nonlinear phenomena due to the impact between a structure and stops have been mainly performed theoretically. It is, therefore, desired to find a way to have a better understanding on the vibration characteristics caused by the impact of a structure to stops. In the paper, both numerical analyses and experiments are conducted for a fixed-free beam that is restrained by the stops at the free end. The chaotic vibration characteristics of the nonlinear motion and the dynamic response of the system are investigated and presented for various magnetic forces between stops.

확장 칼만 필터를 이용한 동적 전기 임피던스 단층촬영법

김봉석,김경연,김민찬,이윤준 濟州大學校 情報通信硏究所 2000 情報通信硏究所論文集 Vol.3 No.-

In electrical impedance tomography (EIT). the resistivity(impedance) distribution of the unknown object is estimated from boundary voltages induced by different current patterns with various reconstruction algorithms. In this paper. we propose a dynamic EIT reconstruction algorithm based on the extended Kalman filter(EKF). The reconstruction problem is formulated as dynamic equation which consists of the state equation and the observation equation and the unknown state is estimated recursively with the aid of the EKF. Computer simulations for the 16-channel synthetic data are provided to illustrate the reconstruction performance of the proposed algorithm.

혈액투석중인 말기신부전 환자에서 Fludrocortisone acetate (FCA) 투여 후 혈청 칼륨 저하 효과

류봉관,강대웅,정지용,윤나라,신병철,박경희,정종훈,김현리 朝鮮大學校 附設 醫學硏究所 2005 The Medical Journal of Chosun University Vol.30 No.1

Background: Hyperkalemia is a commonly encountered problem in dialysis patients with end-stage renal disease. In this study we evaluated the effect of mineralocorticoid therapy (fludrocortisono acetate) on serum potassium level in the serum of hyperkalemic end-stage renal disease patients. Methods: Fourteen patients on hemodialysis receiving fludrocortisone acetate (FCA) 0.1 mg/day were observed for 2 months periods. Consecutive monthly biochemical profiles were compared for the druration of the pre-and post-treatment of FCA. Result: Fourteen patients with mean age (±SE) of 51.5 years (4 males and 10 females) and mean hemodialysis period of 51.9 months were studied. Mean serum potassium levels significantly fell (p<0.05) during the post-FCA period (5.2±0.66 mEq/L) compared with potassium levels during the pre-FCA (5.8±0.43 mEq/L) period. Pre-and post-FCA values were not different for sodium, chloride, protein, albumin, AST/ALT, glucose, blood nitrogen, creatinine, phosphate and calcium. Conclusions: FCA appears to decrease serum potassium value in patients with end-stage renal disease. These results suggested that FCA could be effective to treat hyperkalemia without any adverse effect in patients undergoing hemodialysis.

루프형 히트파이프를 이용한 PC냉각시스템에 관한 연구

김봉환,윤병도,김경훈 경희대학교 산학협력기술연구원 2001 산학협력기술연구논문집 Vol.7 No.-

According to the improvement of PC performance, it is expected that calorific value, which causes PC to malfunction, is increased. Therefore, the development of new cooling system is recently required. As the method to solve this problem, we developed loop type heat pipe. The heat pipe, which is a sealed box attached wicks, has a high performance on heat transfer, using a huge laten heat which is a generated during a phase change. Thermosyphon is a simple sealed tube in which a little working fluid is filled as the state of a static liquid pool. The advantage of heat pipe and thermosyphon is like that these are a small size, light weight, simple shape and long life. In addition, these have a good performance on a heat response and a coefficient of heat transfer, a wide rane of applicable temperature and no a supply of power from the outside. On the other hand, these have defects like that these have a large flow resistance and thermal resistance, and a heat transfer is restrained by the working limit. In this study, it is confirmed that loop type heat pipe reduces a flow resistance and thermal resistance and has a good performance on a cooling effect.

고온설비의 FFS평가를 위한 308 스테인리스강의 크리프 균열성장 재료물성에 대한 연구

이경용,백운봉,윤기봉 한국산업안전학회 2002 한국안전학회지 Vol.17 No.4

For fitness-for-service evaluation of high temperature plant components with defects, crack growth life must be assessed properly as indicated in the recent draft of API 579 code. Type 308 stainless steel has been widely used as a field weld material in the petrochemical industry. In this study, creep crack growth data of type 308 stainless steel are colleted and re-analyzed using C_t as a characterizing fracture parameter. A unique da/dt versus C_t relationship was obtained despite of difference of creep deformation constant or the reviewed materials and specimen geometry of the tested specimens. The obtained results can be employed for crack growth life assessment and fitness-for-service evaluation for the cracks in high temperature components. It is also argued that since the effect of creep properties and other material variability on the creep crack growth behavior would be minor the obtained model may be applied for most of the 308 stainless steels.

공개키 기반 신뢰성 강화 인증시스템 설계

성국경,이봉근,윤성일 공주영상정보대학 2001 논문집 Vol.8 No.-

본 논문에서는 전자 상거래를 위해 암호 기술의 확장성 측면에서 우수한 공개키 기반 하부 구조에서의 공개키 인증 기술을 중심으로 분석하였고, 인증기관에서 발급하고 있는 인증서의 기능을 보강함으로써 인증기관의 신뢰도를 높일 수 있는 신뢰성을 강화한 인증 시스템을 설계하였다. 공개키 기반 인증 기술은 전자 상거래 서비스에서 필요한 신분 인증, 거래 내역 인증 및 지불 처리 인증에 사용하는 기반 기술이다. 이는 공개키를 보증하는 기반 기술과 인증서의 안전한 사용 기술 등이 필요하며 전자 상거래를 실현하기 위한 필수적인 선결 사항이다. 인터넷이라는 불안전한 개발형 전산망 구조에서 안전한 전자 상거래를 제공하려면 향후 국제적인 인증 서비스와의 연동을 위한 표준화된 인증 기술의 적용이 중요하다. 현재까지 정보의 공유라는 원칙에서 발전해 온 인터넷은 앞으로 전자상거래나 전자화폐 등이 인터넷상에 등장함으로 인해 정보의 보호라는 새로운 원칙을 바탕으로 발전해 나아갈 것이다. 이러한 정보보호시대에 살아 남기 위해서는 종속적이 아닌 독자적인 암호화 기술과 데이터 인증기술의 개발이 절실하게 필요한데, 여기에 인증국의 중요성이 부각된다. 현재 암호화 기술은 어느 정도 신뢰를 줄 만큼 발전해 있지만 아직까지 데이터 인증을 위한 기반구조가 명확히 성립되어 있지 않은 상태이다. 앞으로 인증국을 기반으로 한 공개키 기반구조 확립이 빠른 시일 안에 이루어 져야 할 것이다.

Capsaicin이 동통억제효과를 나타내는 기전에 관한 연구

이종은,김봉옥,이원택,윤호,박경아 대한해부학회 1995 Anatomy & Cell Biology Vol.28 No.5

송이 타일 제작시 원료 배합비에 따른 제품 특성 연구

이민규,윤경일,이두성,김주봉 濟州大學校 工科大學 産業技術硏究所 1992 産業技術硏究報告 Vol.3 No.-

This study is to investigate the characteristics of products on mixing ratio of raw materials for scoria tile manufacturing. The water absoprtion of scoria tile decreased as scoria particle size decreased and a ratio of scoria/sand increased. And also the water absoprtion of tile decreased as an amount of cement decreased. Smaller scoria particle size, smaller ratio of scoria and sand, and larger amount of cement enhanced strength and thermal conductivity of scoria tile. The surface pattern of scoria tile became various figures as a ratio of scoria and sand increased. Well mixing of large and small particles made surface pattern of tile diverse.