• The Journal of the Korean dental association
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• v.27 no.8 s.243
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• pp.691-695
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• 1989

Raper가 1925년 소개한 교익방사선사진 촬영법은 나름대로의 독특한 특성을 갖고 있으므로 적절히 이용한다면 환자진료에 많은 도움을 받을 수 있을 것으로 생각되어 재조명해 보고자 한다.

• Proceedings of the Korean Nuclear Society Conference
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• 2003.10a
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• pp.446.2-446.2
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• 2003

• Journal of the Korean Vacuum Society
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• v.4 no.4
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• pp.402-406
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• 1995

MOS(금속 산화막 반도체 접합) 소자가 방사선에 노출되면, 산화막재에 양의 공간전하가 생성되고 Si-SiO2 계면에 계면준위가 생성된다. MOS 커패시터의 방사선 조사효과를 방사선 피폭량과 산화막의 두께를 달리하는 시편에서 정전용량과 전류변화를 측정하여 고찰하였다. 정전용량-바이어스 전압 특성 실험결과로부터 플렛밴드 전압 및 계면상태밀도를 계산하였다. 또한 전압-전류 특성은 방사선 조사로 산화막내에 생성된 양의 공간전하와 Si-SiO2 계면에 포획된 전하에 의해서 설명이 가능하였다.

• The Journal of Korean Society for Radiation Therapy
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• v.14 no.1
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• pp.165-174
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• 2002

Vascular endothelial growth factor (VEGF) has been identified as a peptide growth factor specific for vascular endothelial cells. In this study, we examined the effect of VEGF on radiation induced apoptosis and receptor/second messenger signal transduction pathway for VEGF effect in human umbilical vein endothelial cells (HUVECs). VEGF was found to protect HUVECs against the lethal effects of ionizing radiation by inhibiting the apoptosis induced in these cells by radiation exposure. VEGF (1-30 ng/ml) dose dependently inhibited apoptosis by irradiation. Pre-treatment with Flt-1 and Flk-l/KDR receptor blocked the VEGF-in duced antiapoptotic effect. Phosphatidylinositol 3'-kinase (PI3-kinase) specific inhibitor, Wortman in and LY294002, blocked the VEGF-induced antiapoptotic effect. These data suggest that VEGF may play an important role in survival of HUVECs due to the prevention of apoptotic cell death caused by some stresses such as ionizing radiation.

• Radiation Oncology Journal
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• v.28 no.3
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• pp.147-154
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• 2010

Purpose: To investigate the radiosensitizing effect of the selective epidermal growth factor receptor (EGFR) inhibitor nimotuzumab in human colorectal cancer cell lines. Materials and Methods: Four human colorectal cancer cell lines, HCT-8, LoVo, WiDr, and HCT-116 were treated with nimotuzumab and/or radiation. The effects on cell proliferation, viability, and cell cycle progression were measured by MTT, clonogenic survival assay, flow cytometry, and Western blot. Results: An immunoblot analysis revealed that EGFR phosphorylation was inhibited by nimotuzumab in colorectal cancer cell lines. Under these experimental conditions, pre-treatment with nimotuzumab increased radiosensitivity of colorectal cancer cell lines, except for cell line HCT-116. However, cell proliferation or cell cycle progression was not affected by the addition of nimotuzumab, irrespective of irradiation. Conclusion: Nimotuzumab enhanced the radiosensitivity of colorectal cancer cells in vitro by inhibiting EGFR-mediated cell survival signaling. This study provided a rationale for the clinical application of the selective EGFR inhibitor, nimotuzumab in combination with radiation in colorectal cancer cells.

• Radiation Oncology Journal
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• v.12 no.1
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• pp.43-50
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• 1994

A retrospective analysis was performed on 55 patients with malignant parotid tumor who were treated with radiation therapy between March, 1979 and July, 1989. Of these patients, 8 patients received radiation therapy(RT) alone and 47 patients were treated with combined operation and radiation therapy(OP + RT). The follow-up period of the survivors ranged from 1 to 129 months with a median of 48 months. The common histologic types were mucoepidermoid carcinoma (25 cases), malignant mixed tumor(12 cases), adenoid cystic carcinoma(6 cases). The 5 and 10 year local control rate were 69.8% and 65.7% in all patients. In OP+RT group, prognostic factors related to local control were histologic grade, tumor size, lymph node metastasis. Resection of facial nerve did not affect the local control rate significantly(p=0.129). Distant metastasis developed in 23.6% of patients, mostly to the lung. Actuarial overall survival rate was 72.2% at 10 years and formed plateau after 5 years. Disease-free (NED) survival rate was 49.4% at 10 years and was better achieved in OP+RT group and low grade lesions. Based on our result, a well planned postoperative RT following parotidectomy is highly efficacious in controlling malignant tumors of the parotid gland and preservation of facial nerve.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.515-520
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• 2001

To observe the stimulating effect of low dose ${\gamma}$ radiation on the dormancy breaking and growth, microtubers of two potato cultivars (Solanum tuberosum L. cv. Dejima and cv. Superior) were irradiated at the dose of 0.5-30 Gy. Though it varied with cultivars and storage duration, sprouting rate, plant growth and tuber yield were promoted by 2-8 Gy irradiation in microtuber of 'Dejima' stored at low temperature. On the other hand, in microtuber of 'Superior', sprouting rate was promoted by 2 and 4 Gy irradiation, and the growth and tuber yield by 4 Gy irradiation. These results suggest that low dose of ${\gamma}$ radiation could have stimulating effects on the dormancy breaking of microtuber and potato growth.

• Progress in Medical Physics
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• v.13 no.2
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• pp.69-73
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• 2002

Exposure measurement data with parallel plate ionization chambers were known to depend on the polarity ($k_{pol}$) effect. In this work, the polarity effect were investigated for three parallel plate ionization chambers with different volume. The ionization chamber was fabricated using acrylic plate for the chamber medium and printed circuit board for electrical configuration. The various sizes of the sensitive volumes designed so far were 0.9, 1.9, and 3.1 co. High voltage generator was fabricated using the conventional 9 V batteries to apply the high voltage (300-500 V) to the electrode of the parallel plate ionization chamber. The gap between two electrodes ranged from 3, 6, and 10mm. As the result of our experiment, the polarity effect was within 0.5% in photon beam and 1% to 3.5% in the electron beams. Among electron beams, 16 MeV beam, which had highest energy, showed less polarity effect than electron beams with other energies.

• Korean journal of food and cookery science
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• v.6 no.2
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• pp.97-104
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• 1990

건조 수산가공품 및 혼합조미료 각 5종의 위생적 살균 및 저장방법의 개발을 목적으로 현행살균 방법으로 살균효과의 불충분, 제품의 품질저하, 약제성분의 잔유 등 많은 문제점을 내포한 ethylene oxide에 의한훈증처리와 방사선 조사와의 미생물 살균효과, 이화학적 특성 및 관능적 품질에 미치는 영향을 검토한 결과는 다음과 같다. 시료의 미생물 오염은 전 세균이 $10^3~10^7$ CFU/g으로 그중 90%이상이 내열성 세균이었으며, 곰팡이류는 $10^2~10^3$ CFU/g, 대장균도 시료 5종에서 $10^2~10^6$ CFU/g이나 오염되었다. 살균효과 실험에서 대장균군, 곰팡이류는 5~10 kGy 방사선 조사로서 완전 사멸되었으며, 전세균도 오염도가 매우 높았던 혼합조미료 몇종을 제외하고는 제거되었다. 반면, ethylene oxide훈증처리는 전 미생물의 살균이 불충분하였다. 이 화학적 특성 즉, TBA가 TMA-N 함량, 아미노산, 무기질, 색도 등은 적정 선량의 방사선 조사로서는 무처리구 시료와 거의 차이가 없었으나, ethylene oxide 훈증처리구는 심한 품질의 변화를 나타내었다. 또한 관능검사에 의한 전반적 기호성에 있어서도 방사선조사구가 무처리구 및 ethylene oxide 처리구보다 유의적으로 우수함을 나타냈다.

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.133-140
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• 1984

인체가 방사선에 의해 손상을 받게 되면, 실제적으로 치료, 회복시킨 수 있는 물질은 아직 발견되지 않았다. 이에 저자는 720R의 X-선을 조사시킨 mice에 Oura 등의 방법에 따라 부분 정제한 인삼 추출물을 투여하여 X-선 손상으로부터의 회복능을 검정하였다. 주사한 인삼 추출물의 용량에 의존적으로 30일간의 생존율이 증가하였다. Saline을 주사한 대조군과 인삼 추출물을 주사한 실험군 사이의 생존율의 차이는, 동물 한 마리당 1.8mg을 투여한 실험에서 조차 통계학적으로 유의성을 보였다. (P<0.001) 550R의 X-선을 조사시킨 mice에 인삼 추출물을 투여하면 적혈구와 혈소판의 양적 회복이 촉진되었다. 또한 인삼 추출물중 열에 안정한 분획이 비장이 비대하여지는 것과 같은 부작용이 없어 방사선의 손상으로부터 보호 효과가 있음을 알았다. 이 분획은 mice뿐만 아니라, 반치사량의 X-선을 조사한 rat, guinea pig와 같은 실험동물에 있어서도 30일간의 생존율이 더 연장되므로서 현저한 효과를 보였다. 혈액상태 특히 혈소판의 양적 회복은 열에 안정한 이 분획에 의해서도 촉진되었다. 열에 안정한 분획을 투여한 mice에 있어서 X-선 조사에 의한 출혈이 방지되는데, 이를 매일 매일의 변에서 잠재혈액을 측정함으로써 정량적으로 관찰하였다. 결론적으로, 인삼 투여로 방사선에 의한 치사율이 감소되는데 이의 기전은 혈소판 생성을 촉진시키며, X-선에 의한 출혈을 감소시키기 때문이다.