• Clinical and Experimental Pediatrics
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• 제46권6호
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• pp.554-560
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• 2003

목 적 : 계태의 발생 과정에서 감마선 조사에 의한 심장 기형유발 유무와 심장 기형의 종류를 알아보기 위하여 본 연구를 시행하였다. 방 법 : 토종 닭의 수정란을 사서 닦은 후 대조군에게는 감마선을 조사하지 않았다. 실험군으로 닭의 수정란을 인공 부화기에 넣고 3일 후(72시간 후)에 꺼내어 700 curie 1.25 Mev Cobalt 60에서 나오는 감마선을 50 rad, 100 rad, 150 rad, 200 rad, 250 rad, 300 rad로 각각 60개의 수정란에 조사 후 인공 부화기에 넣어 총 3주간 지속시켰다. 온도 $38^{\circ}C$와 습도 55-70%로 유지하여 3주간 부화시킨 계태를 개흉하여 포르말린으로 고정하였고, 실물 현미경하에 해부하였다. 결 과 : 감마선 조사하지 않은 대조군에서 생존율은 76.4%이었고, 심장 기형은 발견되지 않았다. 실험군에서는 50 rad에서 300 rad로 선량이 강할수록 생존율은 63.3%에서 33.3%로 유의하게 감소하였고(P<0.001), 심장 기형의 발생률도 생존 계태의 7.8%에서 25.0%로 유의하게 증가하였다(P<0.001). 선량이 증가 할수록 심실중격결손의 크기가 증가하고 복잡기형이 나타나는 경향을 보였다(P<0.001). 대혈관 기형도 이상기시, 저형성, 형성부전으로 심해지는 경향을 보였다. 결 론 : 계태 발생 과정 중 감마선 조사의 시기와 선량이 선천성 심장병의 발생에 중요한 영향을 미친다. 조사 시기를 3일 후로 고정한 후 선량이 증가함에 따라 생존율은 감소하였으며, 선천성 심장병의 빈도는 증가하였고, 복잡 심장 기형이 생겼다. 또한 감마선 조사에 의해서 계태에서 혈관 기형을 유발할 수 있었다. 감마선 조사는 계태에 직접적인 조작을 하지 않고 또한 혈역학적 변화를 직접 유도하지 않는 실험이므로 거대분자인 핵산의 변화에 의해서 심장 기형과 대혈관 기형이 발생하였을 것으로 생각하며 기형 형성의 기전을 밝히기 위해 앞으로 염색체와 분자유전학적 연구가 필요할 것이다.

• Radiation Oncology Journal
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• 제1권1호
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• pp.103-109
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• 1983

47 out of 56 cases of intact uterine cervix cancer treated by radiation at the Hanyang University Hospital were followed 18 months or more after treatment. (7 patients died before 18 months, 2 cases lost to follow-up). Age distribution reveal 5 cases in 30's, 18 cases in 40's, 17 cases in 50's, 7 cases in 60's. Histologically, all cases were squamous cell type except one case of adenocarcinoma. 1. 45 cases were treated by combined external Co-60 irradiation and intracavitary irradiation by Cs-137 small sources. 1 case was treated by external irradiation only, and 1 case by intracavitary only. 2. Rectal injuries were observed in 13 cased (27.6%), 4 cases in Grade 1, 8 cased in Grade 2 and 1 cases in Grade 3 which needed surgical management. 3. Average intervals of rectal injury following treatment was 9.2 months varying from 5 to 15 months. 4. Relation between rectal injury and point A dose reveal 6 cases between 7000-7999 rad and 6 cases between 8000-8999 rad and 1 case above 9000 rad. Even though there is no direct relation between point A dose and rectal injury, it is expected that rectal injury increases as point A dose increase. 5. In the normal condition, rectal injury can't be attributed to one major cause. Radiation dose, small source distribution, general condition of patients, local anatomy of the individual patient, history of PID and previous surgery, all play complex roles.

• 대한디지털의료영상학회논문지
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• 제7권1호
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• pp.7-13
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• 2005

Purpose : Image plate (IP) is substituted for film in computed radiography. This study is to investigate into a variation of contrast and detail by the number used of image plate in computed radiography. Materials and Methods : A Contrast-Detail(CD)-RAD 2.0 phantom(Nijmegen hospital, The Netherlands) was used for this study. The computed radiography(CR) CD-RAD phantom images were acquired at 40 kVp, 160 mA, 1.6 mAs, and small focus with the Shimadzu general radiography UD-150B-10 system and Fuji FCR 5000 image process system with speed of 200. The IP used including once, 5000 times, and 10000 times also was used. The numerical value of image quality figures (IQF) was produced by CD-RAD analyser(the program is installed in the directory), and then contrast-detail curve was drawn. Results : In this study, the value of IQF was 3.53 in IP used once, 3.40 in 5000 times, and 3.22 in 10000 times. Conclusions : There was a variation of contrast-detail curve by the number used of IP with contrast-detail phantom in computed radiography. Therefore, it is necessary that the IP with lower IQF and a shift of contrast-detail curve to the lower left part is used.

• Radiation Oncology Journal
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• 제7권1호
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• pp.1-13
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• 1989

Effects of ionizing radiation alone and combined with chemotherapy on tumor growth and it's clonal specificity monitored by changes in distribution of chromosome number were studies in A549 ceil line originated from human adenocarcinoma of the lung. Radiation (300 rad, 600 rad and 900 rad) were delivered with or without 5-FU. Forty eight hours later, 57.5% of growth inhibition of cell w8s seen in cells treated with 5-FU concentration of $0.4{\mu}g/ml$ for 24hr exposure. Cell survival curves after radiation with and without 5-FU were made. Chromosomal analysis of cells in metaphase in control, and in cells treated with 300 rad of radiation, or $0.4{\mu}g/ml$ of 5-FU treatment, and combined treatment of both were done to examine the changes in ploidy and number of chromosome. Radiation combined with S-FU enhanced growth inhibition of A549 cells. However, no evidence of synergegic effects in growth. inhibition was observed in the cells treated with the combination therapy. Pattern of chromosomal distribution of survived cells were shifted from hyperploidy to hypoploidy by single dose of radiation (300 rad). As radiation dose increased a large number of hypoploidy cells were observed. Following treatment of cells with 5-FU, chomosomal distribution of survived cells were also shifted to hypodiploidy which were seen in cells treated with radiation, The ceil treated with 5-FU and fellowed by radiation within 24 hrs had cell with increased number of hypodiploidy cells. Almost same type of chromosomal changes were reproduced in cells treated with combined treatment with radiation and 5-FU. Minor differences were that cells with fewer number of chromosome were more frequent in cells treated with combined therapy. Further increase in cells of hypoploidy (93%) having 1-10 chromosome were induced by additional radiation. Therefore, the enhanced therapeutic effect of 5-FU combined with radiation of A549 cells appeared to be additive rather than synergistic.

• 한국정보통신학회논문지
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• 제18권7호
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• pp.1777-1783
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• 2014

본 연구에서는 전자장비 내방사화 기술의 새로운 효율적 접근방법인 전원제어형 방호장치에서 핵심 기능을 수행하는 고속 반도체 센서를 개발하고 그 특성을 분석하였다. 먼저, 펄스방사선에 의한 다이오드 내부에서의 생성 전하를 계산한 후 TCAD로 모델링하여 $42{\mu}m$ 진성층의 실리콘 에피텍시 웨이퍼 기반의 고속 신호탐지용 PIN 다이오드 센서를 다양한 구조로 설계하였다. PAL의 Test LINAC의 전자빔 변환 감마방사선 4.88E8 rad(Si)/sec에 대한 실측시험에서 소자의 면적에 비례하는 광감도와 응답속도 증가 결과를 얻었으며 포화특성과 소자의 균일성을 기준으로 2mm직경의 센서를 최적으로 판단되었다. 선정 센서를 대상으로 한 펄스감마선 고출력 범위(2.47E8 rad(Si)/sec~6.21E8 rad(Si)/sec)로 선량률 가변시험에서는 개발한 소자가 시험장치의 고 선량률 영역에서 전원제어 신호처리에 충분한 60mA 이상의 광전류 피크값과 함께 350 ns 이하의 고속 응답특성을 가지는 선형적 센서임을 확인하였다.

• Nuclear Engineering and Technology
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• 제29권3호
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• pp.181-185
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• 1997

The ion sources for induction linac driven heavy ion fusion were fabricated and their omittance characteristics were investigated. For to kinds of ion sources, i. e. a carbon vacuum arc ion source and a cusp field rf ion source, the emittance was measured with a double slit beam scanner. The required normalized omittance of an ion source for heavy ion fusion is 10$^{-7}$ - 5$\times$10$^{-7}$ $\pi$ m-rod, and the measured emittances of the ion beams from carbon vacuum arc ion source and cusp field rf ion source (Ne$^{+}$) were 2$\times$10$^{-6}$ $\pi$ m-rad and 4$\times$10$^{-7}$ $\pi$ m-rad, respectively.y.

• 미생물학회지
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• 제18권1호
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• pp.1-6
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• 1980

Five species of food decay fungl, Aspergillus flavus, Asp. uiger, Penicillum sp., Botrytis cinerea, and Rhizopus stolonifer, were examined for their radio sensitivity in several suspension media. Asp. flavus, Asp. niger and Penicillum sp. have almost the same sensitivity toward gamma rays. with D value in the range of 30 to 35 K rad, whereas Botrytis cinerea has a D value of approximately 55K rad and Rhizopus stolonifer, the most re4sistant fungus studied, has a crease in their radioresistnace when compared with spores irradiated in water. Asp. flavus and penicillium sp. spores irradiated in citrate buffer at pH3-7 showed almost no change in their radisensitiity with pH, but Botryis cinerea spores showed a distinct decrease in their radioresistnace at pH 6 and 7. Penicillum sp. spores irradiated in sucrose solutions showed no sinificant change in their radioresistance. Botrytis cinerea spores displayed a higher radioresistance when they were irradiated in sucrose solution than in water.

• 항공우주기술
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• 제6권2호
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• pp.219-228
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• 2007

구름 검출 시 사용되는 인자들에 따른 Landmark 정합의 정밀도 변화를 추정하기 위한 시험을 수행하였다. 본 시험을 위해서 MTSAT-1R의 7개 영상을 이용하였으며, Landmark 정합의 정밀도는 대략 0.1 화소 이하로 추정됨을 확인할 수 있었다.

• 한국방사선학회논문지
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• 제8권3호
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• pp.137-145
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• 2014

방사선과 paraquat에 의해서 유도된 간 손상에 대한 홍삼추출물의 보호효과를 비교 연구하였다. ICR계 생쥐에게 X선의 5Gy조사와 paraquat투여 7일 전부터 홍삼추출물(200mg/kg/day)을 투여하였다. 대조군은 생리적 식염수를 투여하고 방사선조사군은 생리적 식염수를 투여하면서 5Gy를 조사하였다. 홍삼추출물 투여군은 7일 전부터 홍삼추출물(200mg/kg/day)을 투여하면서 5Gy를 조사하였다. Paraquat투여군은 7일 전부터 홍삼추출물(200mg/kg/day)을 투여하면서 paraquat(30mg/kg/day)를 투여하였다. 그리고 각각의 실험군에서 간조직의 H2O2, catalase, MDA를 측정하였다. 그 결과 방사선조사군과 paraquat투여군보다 홍삼추출물 투여군에서 catalase함량이 유의성 있게 증가하여 간의 보호효과가 있었으며 H2O2와 MDA함량도 유의성 있게 감소하였다. 홍삼추출물은 간 조직에 대한 방사선조사 및 paraquat투여로부터 매우 우수한 방호제라고 할 수가 있다.

• 대한방사선기술학회지:방사선기술과학
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• 제2권1호
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• pp.15-22
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• 1979

Author made a experiment on the exposure dose with various intensifying screens in taking chest roentgenogram and obtained the results as follows; 1. Special speed type was the most sensitive intensifying screen, the r(gamma) value of this screen was distributed from 2.6 to 2.9. 2. The resolution activity of intensifying screen was inversely proportional to its sensitivity. If, the sensitivity and detail of the fine detail speed type intensifying screen at 100 KV were 100, those of the special speed type were 549 and 54.44 respectively. 3. If the exposure dose of the fine detail type intensifying screen was 1.0 at 60 KV, that of the special speed type intensifying screen was 0.1 at 80KV, and the skin dose of patient was as follows; it was 64.8 mRad at 60KV in mid speed type, 8.1 mRad at 80KV in super high speed type, and 7.2 mRad at 80KV in special speed type intensifying screen respectively.