• Radiation Oncology Journal
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• v.26 no.2
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• pp.96-103
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• 2008

Purpose: To conduct a nationwide academic hospital patterns of the practice status and principles of radiotherapy for prostate cancer. The survey will help develop the framework of a database of Korean in Patterns of Case Study. Materials and Methods: A questionnaire about radiation treatment status and principles was sent to radiation oncologists in charge of prostate cancer treatment at thirteen academic hospitals in Korea. The data was analyzed to find treatment principles among the radiation oncologists when treating prostate cancer. Results: The number of patients with prostate cancer and treated with radiation ranged from 60 to 150 per academic hospital in Seoul City and 10 to 15 outside of Seoul City in 2006. The primary diagnostic methods of prostate cancer included the ultrasound guided biopsy on 6 to 12 prostate sites(mean=9), followed by magnetic resonance imaging and a whole body bone scan. Internal and external immobilizations were used in 61.5% and 76.9%, respectively, with diverse radiation targets. Whole pelvis radiation therapy(dose ranging from 45.0 to 50.4 Gy) was performed in 76.9%, followed by the irradiation of seminal vesicles($54.0{\sim}73.8$ Gy) in 92.3%. The definitive radiotherapy doses were increased as a function of risk group, but the range of radiation doses was wide(60.0 to 78.5 Gy). Intensity modulated radiation therapy using doses greater than 70 Gy, were performed in 53.8% of academic hospitals. In addition, the simultaneous intra-factional boost(SIB) technique was used in three hospitals; however, the target volume and radiation dose were diverse. Radiation therapy to biochemical recurrence after a radical prostatectomy was performed in 84.6%; however, the radiation dose was variable and the radiation field ranged from whole pelvis to prostate bed. Conclusion: The results of this study suggest that a nationwide Korean Patterns of Care Study is necessary for the recommendation of radiation therapy guidelines of prostate cancer.

• Journal of Radiation Industry
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• v.7 no.2_3
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• pp.141-147
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• 2013

The simple and facile radiation technique of the preparation of antibacterial biodegradable polymer films containing silver nanoparticles (Ag NPs) was described. The biodegradable poly(butylene adipate-co-terephthalate) (PBAT) films containing silver trifluoroacetate (Ag TFA) were prepared by a solvent casting method, and then the films were irradiated by electron beams at the various doses ranging from 20 to 200 kGy to form Ag NPs in the biodegradable polymers. The results of UV-vis and FE-SEM/EDX analyses revealed that the Ag NPs were successfully formed in the PBAT matrix during the electron beam irradiation, and their amounts were dependant on the absorbed dose and Ag TFA concentrations. Furthermore, on the basis of the results of the antibacterial test through disk diffusion and colony counting test, the irradiated PBAT/Ag TFA films exhibited the antibacterial property due to the formation of Ag NPs.

• Nuclear Engineering and Technology
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• v.55 no.5
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• pp.1671-1676
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• 2023

The influence of adding iodine as a contrast substance to elevate radiation in a tumor is studied using simulation techniques of Monte-Carlo. The study is carried on a brain cancer by adopting an unsophisticated head phantom. The ionizing radiation source is an external beam of x-rays with energy range of a few tens of keV. The expected radiation dose increment due to adding the iodine is investigated by comparing the radiation in the tumor after and before adding the iodine and calculating the ratio between the two doses. Several concentrations of the contrast substance are used to quantify its impact. The change of the dose increment with the source energy is also examined. It is found that the radiation elevation in the tumor tends to saturate with increasing the iodine concentration, and for the studied domain of energies (30 keV-100 keV), the radiation dose enhancement factors (RDEF) for the different iodine concentrations (1%-9%) show peaked curves, with the peak occurring between 60 keV and 70 keV. For the highest concentration studied, 9%, the peak value is almost 7.

• Radiation Oncology Journal
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• v.12 no.3
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• pp.323-329
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• 1994

Purpose: In supraglottic cancer, radiation therapy is used to preserve the laryngeal function but combined surgery and radiation therapy is required in advanced stage. The authors Present the results of radiation therapy alone and combined surgery Plus Postoperative radiation therapy for supraglottic cancer. Methods and Materials: A retrospective analysis was done for 43 patients with squamous cell carcinoma of the supraglottic larynx who were treated from Feburary 1982 to December 1991, in the Department of Radiation Oncology, Korea University Hospital. Patient distribution according to the AJCC staging system was as follows: I, 3($7.0\%$); II, 7($16.3\%$); III, 17($39.5\%$); IV, 16($37.2\%$). Patients' age ranged from 30 to 72 years(median 62). Follow up durations were from 21 to 137 months(median 27). Seventeen patients($39.5\%$) were treated by radiation therapy alone with radiation doses of 6840-7380 cGy and 26 patients($60.5\%$) were treated with surgery plus postoperative irradiation with doses of 5820-6660 cGy. Results: Overall five-year survival rate for all stage was $51.8\%$, with $100\%$ for Stage I and II, $47.3\%$ for Stage III, and $29.2\%$ for Stage III. The difference of the survival rate by stage was statistically significant(p=0.0152). Five-year survival rates were $100\%$ for locally confined tumor in the supraglottic larynx, $37.5\%$ for transglottic extension, $26.7\%$ for hypopharynx extension, and only two of 5 patients with both transglottic and hypopharynx extension were alive(p=0.0033). Five-year survival rates by neck node status were as follows: $55.0\%$ for NO, $64.3\%$ for N1, $50.0\%$ for N2, and all 2 of N3 were died of disease. Overall survival rate for radiation therapy alone group was $42.8\%$, and it was $56.7\%$ for surgery plus postoperative radiation therapy group with no statistically significant difference(p=0.5215). In Stage I and II, all Patients survived. In Stage III and IV, 5-year survival rate for radiation therapy alone group was $28.5\%$ and $43.4\%$ for surgery plus postoperative irradiation group(p=0.5103). Local control rate was $58.8\%$(10/17) for radiation therapy alone group and $73.1\%$ (19/26) for surgery plus postoperative irradiation group. Three patients from surgery plus postoperative radiation therapy group developed distant metastasis in lungs. Conclusion: Treatment results of radiation therapy alone was excellent in early stage supraglottic cancer. In advanced stage, even the difference was statistically not significant, the result of postoperative radiation therapy group was superior compared with radiation therapy alone group. Since 1992, concomitant chemoradiotherapy with hyperfractionated radiotherapy is being used to improve the result of the treatment and preserve the laryngeal function in advanced stage supraglottic cancer.

• Journal of radiological science and technology
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• v.7 no.1
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• pp.35-40
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• 1984

Side-direction scattered dose from various radiation shielding materials was measured at 50cm distance from the central beam of primary ray by used several kinds of added filters for a x-ray deep therapeutic installation, the obtained results were as follows : 1. Dose rate by tube voltage was more increased at heavy filtration than light filtration. 2. Scattered doses produced by constant tube voltage in all shielding materials were decreased at heavier filtration. 3. Scattered doses produced by constant shielding material in all tube voltages were decreased at heavier filtration.

• Journal of Ginseng Research
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• v.8 no.1
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• pp.38-44
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• 1984

In order to investigate the influence of gamma-irradiation on fatty acids in ginseng, ginseng were irradiated with various radiation doses(0-50 Mrads). The results are as follows. 1. With increasing dose, standard fatty acids were decreased in the order of linolenic acid, linoleic acid and oleic acid, and their contents in the presence of oxygen were decreased more t than that in the absence of oxygen. 2. Changes of lipid content in white ginseng by gamma irradiation were varied with the samples, but the changes of crude lipid and purified lipid in a sample were showed same fashion. 3. The fatty acid contents in white ginseng were decreased by gamma irradiation in the order of linolenic acid, linoleic acid, oleic acid, stearic acid and palmitic acid.

• Journal of Radiation Protection and Research
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• v.13 no.2
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• pp.88-94
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• 1988

The radiological impacts due to transportation of irradiated PWR fuel by truck were assessed for incident-free and accident conditions with. the computer code INTERTRAN. The resulting collective doses exposure to different subgroups of the public and of the workers were determined. Resulting collective doses for crewman and the public sharing the transport link and living in a corridor on either side of the route are small. All attempts to quantify the risk from the transport suffer from a lack of good input data. It is in these areas that the most important advances can be made.

• Parasites, Hosts and Diseases
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• v.41 no.1
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• pp.41-45
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• 2003

Effects of gamma irradiation on the worm survival and chromosomal aberration of Clonorchis sinensis were studied. The metacercariae irradiated with various amounts of gamma radiation (ranging from 5 Gy to 50 Gy) were fed to rats, and the effects were compared with those of non-irradiated controls. Recovery rates of adult worms in irradiated groups were reduced gradually as increasing of the irradiation doses. No worm was recovered from rats which were fed with 50 Gy irradiated metacercariae. The chromosome number was 2n = 56 in all worms from all experimental groups. However, the groups irradiated with 20 Gy, 25 Gy or 30 Gy showed variations in the chromosome number, depending on different cells in the same individual. Radiation doses used in this study did not appear to induce chromosome aberrations, however, irradiation with 30 Gy showed slightly reduced chromosome size.

• Radiation Oncology Journal
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• v.7 no.1
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• pp.81-83
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• 1989

This study, involving thirty-two patients with carcinoma of uterine cervix treated by high dose rate intracavitary irradiation using a remotely controlled afterloading system, compares the doss at point A and 8 with the Curie-minutes prescription. A linear least-square regression analysis was used to compare the two sets of date. Correlation coefficients between doses at points A and B and the Ci-min prescription are 0.92 (p<0.001) and 0.90 (p<0.001), respectively, and linear relationship is observed between these two system. The limitation and significance of the comparison of the two approaches to intracavitary dosimetry is discussed.

• Journal of the Korean Society of Safety
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• v.19 no.3 s.67
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• pp.26-31
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• 2004

The radiation-induced changes taking place in poly(vinylidene fluoride) (PVDF) exposed to $^{60}Co$ $\gamma-ray$ irradiation were investigated in correlation with the applied doses. Samples were irradiated in air at room temperature by $^{60}Co$ $\gamma-ray$ to doses in the range of 200 to 1000kGy. Various properties of the irradiated PVDF were studied using FTIR, differential scanning calorimetry (DSC), gel fraction and elongation. $^{60}Co\gamma-ray$ irradiation was found to induce changes in chemical, thermal, mechanical and structural properties of PVDF and such changes vary depending on the radiation dose.