감마선에 조사된 생쥐에 있어서 방사선방어효과 평가를 위한 생물학적 파라메타

천기정,김봉희,이영근,김진규 충남대학교 약학대학 의약품개발연구소 1999 藥學論文集 Vol.15 No.-

This study deals with the biological changes in mice after γ-irradiation. Four weeks old BALB/c mice were irradiated with 6.5Gy of γ-ray on the fifth day after oral administration of radioprotectants such as ascorbic acid, tocopherol and cysteine. Control group was irradiated with 6.5Gy without pre-administration of radioprotectors. Blood cells and sperm cells were counted and body, testis and spleen were weighed 3 days after irradiation. And also liver antioxidant activity and range of spleen immune cells were measured. Differences in most biological parameters were not clearly distinguished between experimental groups. However, the relative spleen weight, the relative testis weight and the population size of spleen immune cells such as T helper cells, B cells and macrophages measured by means of FACS showed significant difference between irradiated and radioprotectant administered group. It is concluded that the relative spleen weight, the relative testis weight and the population size of spleen immune cells are easy and useful parameters for assessing the effect of radioprotective substances and for quantifying biological damage of radiation, as well.

비보강 조적벽체 전단내력산정에 관한 연구

이봉근,이정한,이원호,오상훈,나정민 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1(구조계)

In Korea, more than four hundred earthquakes with medium intensity centered on off-coastal and inland of Korea during the past 20 years and due to the great earthquakes which occurred recently in neighboring countries the importance of the future earthquake preparedness measures in Korea is highly recognized. More than 80 percents of residential buildings are constructed with unreinforced masonry structure, in Seoul. In general, unreinforced masonry structure don't have enough strength against the lateral force. And low rise buildings such as unreinforced masonry structure didn't adopted seismic design. So, a huge damage is expected when an earthquake occurs. It is that the major variables of shear strength are the aspect ratio, the vertical strength and the method of masonry. The objectives of this study are, 1) to find out the shear behavior of masonry wall and the variables affect the shear capacity of masonry wall such as aspect ratio of the unreinforced masonry wall, and the vertical strength, 2) to propose the equation of the shear capacity of masonry wall by regression analysis using the test data.

파손된 치면열구전색제의 수리 방법에 따른 미세누출 비교

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

치면열구전색은 수 십년간 교합면 우식의 예방에 가장 효과적인 방법 중 한가지로 알려져 왔다. 하지만 치면열구전색제의 마모와 파절 때문에 치면열구전색제의 재시술 또는 수리를 필요로 하게 되었다. 본 연구의 목적은 파손된 치면열구전색제를 수리할 때 치질과 잔여 전색제의 표면처리 방법에 따른 미세누출 차이를 알아보고자 하는 것이다. 120개의 영구 대구치에 치면열구전색제를 적용하고 인위적인 파손을 만든 뒤 인공타액에 4주 동안 보관하였다. 4주 후 근심 또는 원심의 치면열구전색제가 완전히 파손 양상을 나타내는 치아 60개를 선택하여 각각 15개씩 4개 군으로 나누어 실험에 사용하였다. 각 군을 산부식만 시행한 경우(1군), air-abrasion만 시행한 경우(2군), 산부식 후 결합제를 적용한 경우(3군), air-abrasion 후 결합제를 적용한 경우(4군)로 나눠 각각의 치아를 표면처리한 후 치면열구전색제를 도포하였다. 고온(55℃)과 저온(5℃)에서 각각 30초씩 500회의 열순환을 시행한 뒤 미세누출도를 검사하여 다음과 같은 결과를 얻었다. 1. 치면열구전색제/치면열구전색제 경계면에서 미세누출도는 결합제 사용 유무에 관계없이 air-abrasion을 처리한 2군, 4군에서 산부식을 사용한 1군, 3군보다 낮은 값을 보였고(p<0.05) 1군과 2군, 3군과 4군 사이에는 통계적 유의차가 없었다(p>0.05). 2. 치면열구전색제/치아 경계면에서 미세누출도는 결합제를 사용한 3군, 4군에서 결합제를 사용하지 않은 1군, 2군보다 낮은 값을 보였고(p<0.05) 산부식을 사용한 1, 3군과 air-abrasion을 사용한 2, 4군 사이에는 통계적 유의차가 없었다(p>0.05). 3. SEM 상에서 치면열구전색제를 산부식 처리하였을 때 표면거칠기의 증가가 적었으나 air-abrasion 하였을 경우 표면거칠기가 현저하게 증가하는 것을 관찰하였다. The aim of this study was to investigate whether differences in surface treatment Prior to repair influenced the seal of a resin fissure sealant placed on the occlusal surfaces of permanent molar teeth. One hundred and twenty extracted human molars were selected and a light curing sealant was placed on their occlusal surface following cleaning by prophylaxis and acid etching. The teeth were deliberately damaged, and then stored in artificial saliva for four weeks. Sixty teeth with the desired morphology of sealant failure were randomly divided into four groups where one group was treated with only etching agent, another by only air-abrasion, another by applying an etching agent followed by a bonding agent, and the last by air-abrasion followed by a bonding agent each. After sealant application, the samples were thermocycled and the degree of microleakage was determined. The results were as follows: 1. In the sealant/sealant interface, group 2(0.22), 4(0.23) using air-abrasion showed a significantly lower microleakage score than group 1(0.38), 3(0.35) using an etching agent(p<0.05). There were no statistically significant differences(p>0.05) between groups 1, 2 and groups 3, 4. 2. In the sealant/tooth interface, group 3(0.20), 4(0.20) which used a bonding agent showed a significantly lower microleakage score than group 1(0.35), 2(0.40)(p<0.05). There were no statistically significant differences (p>0.05) between groups 1, 3 and groups 2, 4. 3. In SEM examination, while sealant surfaces treated with etching did not result in highly rough surfaces, those treated with air-abrasion did show rough surfaces.

인천 인현동 호프집 화재 피해자 분석

최정태,안무업,안희철,최영미,정재봉,서정열,유기철,이삼우,박석현,조준휘,김성환,김아진,송근정 대한응급의학회 2001 대한응급의학회지 Vol.12 No.4

Purpose : This study was conducted to develop field triage, transportation, distribution, and prehospital care at a fire disaster by analyzing the victims of the fore that broke out at a bar in Incheon. Method : We analyzed the cases of the victims of a fire in Incheon in Oct. 1999. We determined the primary care hospital, the arrival time, the burn size, the outcome, and the injury type from the medical records, the concerned organ records, and interviews with concerned persons. Result : The total number of victims was 137: 56 prehospital deaths, 1 hospital death, and 80 survivals. The Pearson correlation coefficient between the burn size and the severity was -0.175. There were 121(89.6%) cases of inhalation injury, 59 (43.7%) cases of flame burns, 66 (48.9%) cases of hypoxic brain damage, and 16 (11.9%) cases involving other types of injury. Conclusion : The causes of death of the fire victims were inhalation injury and hypoxic brain damage due to CO poisoning and other toxic inhalants. We propose the use of a simple triage and rapid treatment(START) system and a reassessment the delayed category in fire disasters.

Transthyretin의 Glutathione 자동산화 촉진작용

박종근,정신,김재휴,김수한,강삼석,이제혁,안봉환 대한신경외과학회 1994 Journal of Korean neurosurgical society Vol.23 No.8

When reduced glutathione(GSH) was incubated at neutral pH and at 37°, its concentration decreased slowly with formation of oxidized glutathione(GSSG). Autooxidation of GSH was accelerated by Cu^(2+) and Hg^(2+), but not by other common mono-, di-, and tri-valent cations. Transthyretin was found to stimulate autooxidation of GSH in the presence or absence of Cu^(2+) and Hg^(2+). EDTA inhibited perfectly the autooxidation of GSH regardless of the presence of transthyretin. The stimulating activity of transthyretin was maximal at pH 7.0, declining progressively with increase or decrease of pH from 7.0. Sulfhydryl-blocking agents such as p-hydroxymercuribenzoic acid and Nethylmaleimide markedly inhibited the stimulating activity of transthyretin. Transthyretin stimulated autooxidation of other sulfhydryl compounds such as clithiothreitol and cysteine. However, it did not show a significant effect on autooxidation of sulfhydryl group of egg albumin and eye lens proteins. And transthyretin did not cause any oxidative change to thyroxine(T₄), 3, 5, 3Ltri iodo thyronine(T₃) and 3, 3: 5~triiodothpnine(rT₃) bound to it in the presence of GSH and Cu^(2+). The above results suggest that transthyretin may play a role in regulation of oxidized status of sulfhydryl groups in blood plasma and cerebrospinal fluid

상정사고 해석을 위한 위상각 및 전압 행렬 계산에 관한 연구

金龍根,李鳳容,金正勳 弘益大學校 科學技術硏究所 1993 科學技術硏究論文集 Vol.3 No.-

This paper proposes a simple and efficient contingency analysis algorithm to find after-states without increasing computation efforts. Conventional methods are based on the matrix inversion lemma and two times of forward and backward substitutions are required to find modified angles. The proposed method which is based on the matrix iterative solution is a simple decoupled load flow with slightly modified formulations, and thus we can find new angles and voltages. With two iterations of the proposed method the computation efforts are equivalent to the conventional, since this requires only one forward and backward substitution per iteration. The proposed method is tested for IEEE 14 and 30 bus systems, and it shows that the solution accuracy is superior to and the efficiency is comparable with, DC load flow calculation. .

쇠비름 수침액이 방사선 조사에 의한 생쥐의 생존율과 뇨중 아미노산 조성에 미치는 영향

천기정,김진규,이영근,김봉희 충남대학교 약학대학 의약품개발연구소 1999 藥學論文集 Vol.15 No.-

A study has been conducted to investigate the radioprotective effects of purslane extracts (P) when I.p. injected before irradiation (R). For studying the amino acid composition , three groups of ICR mice (7-week-old) were tested. The first group I.p. injected with purslane extract for 5 days were irradiated with 6 Gy of γ-radiation (P+R). The second group was irradiated with 6 Gy without any pretreatment (R). The third group was non-irradiated control (CT). Each group divided into two groups for the survival rate study, one injected with saline (S) and the other injected with purslane extract (P) for five days and then irradiated with 8 Gy. The amino acid composition of urine samples were analyzed with HPLC for 19 days after irradiation. A few kinds of amino acids such as lysine and methionine in urine from P+R group increased in comparison with those from CT or R group. The survival rate of P group maintained much higher than that of S group during experimental period. The results obtained may support that this plant has radioprotective substances by means of life-lengthening, not of urine amino acid components.

대학생의 기본 심폐소생술 교육 평가 : 간호과와 비간호과를 대상으로

이정은,고봉연,이인모,최근명,박신일,안홍기 한국응급구조학회 2003 한국응급구조학회지 Vol.7 No.1

The purpose of this study was to evaluate the accuracy of CPR skills and the satisfaction of CPR Training targeted for college students. Also, this study made comparative study of nursing students and non-nursing students. The sample consisted of 248 students(132 nursing students, 116 non-nursing students). CPR Training was designed by two components which were a lecture and demonstration by one professor and individual practice 표 instructors. As tool of measurement estimation satisfaction of CPR Training questionnaires were developed based on educated contents. The accuracy of CPR skills were checked by SkillReporter CPR training manikin. Collected data were computerized and analyzed by SPSS-WIN program. The results were as follows : 1. The skills of CPR were cardiac compression 92.79 times/min, correct cardiac compression rate 90.85%, ventilation 9.93 times/min. correct ventilation rate 79.34%. 2. The mean of the accuracy of CPR skills were 2.94(SD .87). 3. When errors were analyzed, the highest item was stomach distension(51.2%) of ventilation skills and too little(70.6%) of cardiac compression skills. 4. The mean of the satisfaction of CPR training were 2.87(SD .17), the highest item of the satisfaction of CPR Training was practice. 5. We found significant statistical differences based on the accuracy and the error, non-nursing students were high in correct cardiac compression per minute(t=3.615, p=0...) and ventilation too much(t=4.292, p=.000), nursing students were high in correct ventilation rate(t=-3.885, p=.000) and cardiac compression too shallow) t=-2.842, p=.005).

대구시 중구의 옥상녹화를 통한 환경 및 경제적 편익 분석

김수봉 ( Soo Bong Kim ),장중근 ( Jung Keun Chang ) 한국환경과학회 2007 한국환경과학회지 Vol.16 No.5

급성기 뇌지주막하출혈에서 Three-Dimensional Computed Tomographic Angiography (3-D CTA)의 유용성

임동준,이훈갑,김봉룡,정흥섭,정용구,이기찬,서중근 대한신경외과학회 1998 Journal of Korean neurosurgical society Vol.27 No.12