• 대한방사선방어학회:학술대회논문집
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• 2009.11a
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• pp.42-43
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• 2009

• Journal of Photoscience
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• v.9 no.3
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• pp.37-40
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• 2002

Astronauts are constantly exposed to space radiation at a low-dose rate during long-tenn stays in space. Therefore, it is important to determine correctly the biological effects of space radiation on human health. Space radiations contain various kinds of different energy particles, especially high linear energy transfer (LET) particles. Therefore, we have to study the relative biological effectiveness (RBE) of space radiation under microgravity environment which may change RBE from a stress for cells. Furthermore, the research about space radiation might give us useful information about birth and evolution of life on the earth. We also can realize the importance of preventing the ozone layer from depletion by use of exposure equipment to sunlight at International Space Station (ISS).

• Radiation Oncology Journal
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• v.7 no.2
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• pp.259-267
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• 1989

Forty one patients with para-aortic node metastases from carcinoma of the uterine cervix treated with radiotherapy at Department of Radiation Oncology, Yonsei University, College of Medicine from January 1982 to December 1987 were retrospectively analyzed. Eleven patients were diagnosed at the time of diagnosis of carcinoma of the cervix (early diagnosis) and 30 patients were diagnosed during follow up period after definitive radiotherapy of primary site (late diagnosis). The most important factors affecting the survival in this study were time of diagnosis and dose of irradiation. Overall 5 year actuarial survival rate of 41 patients was $25.7\%$. Five year survival rate for early diagnosis was $60.3\%$, but late diagnosis was $16.9\%$. And survival rate for high dose (over 4000 cGy) radiation group and low dose radiation group were $42.2\%\;and\;8.9\%$ respectively The most leading cause of death was para-aortic node failure, so early diagnosis and maximum palliation with full dose radiotherapy (over 4000 cGy) is necessary to improve the survival and the quality of life.

• Journal of Korean Neurosurgical Society
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• v.65 no.5
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• pp.633-639
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• 2022

Accurate diagnosis of trigeminal neuralgia (TN) is the starting point for optimal treatment. Gamma knife radiosurgery (GKRS) is currently regarded as one of the first-line treatment options for medically refractory TN. GKRS is a less invasive treatment with a low risk of complications than other surgical procedures that provides a favorable pain control Barrow Neurological Institute (BNI) I-IIIb rate of >75% at short-term follow-up. Drawbacks of GKRS include the latency period before pain relief and higher recurrence rate compared with microvascular decompression. Therefore, repeat treatment is necessary if the initial GKRS was effective but followed by recurrence. The concept of dose rate and the biologically effective dose of radiation has been actively studied in radiation oncology and is also applied in GKRS for TN to achieve high safety and efficacy by prescribing the optimal dose. Recent progress in functional imaging, such as diffusion tensor imaging, enables us to understand the pathophysiology of TN and predict the clinical outcome after GKRS. Here, we review TN, GKRS, and recent updates, especially in the concepts of radiation dose, diffusion tensor imaging studies, and repeat treatment in GKRS for TN.

• Journal of Radiation Protection and Research
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• v.39 no.3
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• pp.134-141
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• 2014

Along with the wide use of radiotherapy in cancer treatment, there is growing interest in beneficial effect of low-dose irradiation (LDI) in cancer therapy. Therefore, we investigate how LDI affects immune responses in mice model. Total body irradiation (TBI) on C57BL/6 mice was given at low-dose rate of $1mGy{\cdot}min^{-1}$ using $^{137}Cs$ source at three times for consecutive three days. Hematological examination, total cell numbers of spleen, populations and characteristics of splenocytes were determined. Total numbers of RBC or platelet in irradiated mice showed no significant changes. WBC counts were decreased in a dose-dependent manner 2 days after TBI, however, these differences are gradually waned until 28 days. Dose-dependent decrease in the number of splenocytes of TBI mice at day 2 was also improved as time progressed. While the level of Foxp3 mRNA was decreased, the frequency of $CD4^+$ T cells and $CD69^+$ cells in spleen was increased at day 2 and 14. Fractionated low-dose TBI on mice exhibited normal body weight with no distinguishable behavior during whole experimental periods. These results suggest that some parameters of immune system could be altered and evaluated by fractionated low-dose TBI and be used to broaden boundary of low dose radiation research.

• Journal of Society of Preventive Korean Medicine
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• v.3 no.1
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• pp.35-54
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• 1999

This thesis shows about the meaning of treatment rate increasing, the current treated level and the reason of low treatment rate and increasing methods. 1. Treatment rate incresing means high treat level within short time, keeping treatment effect for a long time as well as raising treatment rate. 2. The current by diseases each others completed treatment rate of oriental medicine is 14.0% to 89.7%$(mean:\;{\pm}40.0%)$. Therefore the rate is show too low. 3. The reasons of low treatment rate; low academic level of oriental, academic limitation, clinic and prevention problem of oriental medicine, lack of medical approch suitable for current diseases and symptoms, mostly incurrable diseases using oriental medicine, lack of preventive education, disappropriate medical service and nonspecialty of the treatment, etc. 4. The next methods for incresing the treatment rate must be improved; such as accurate establishment of process that diagnosis symptoms and treats them, system research of microdiagnosis, positive treatment with medicine and nonmedicine method at the same time, appropriate subdivision and actualization of clinical basic research, research of dose and response, diversity of treatment methods and forms, development of treatment service and prevention based on health level, enormous change as cure medicine and opening-up of new disease field, specialization of medical examination, reinforcement of public medical part and herbal drugs use with same origin, mental and pysical stability of patients, accurate extract and oral drinking ways, etc.

• Journal of Radiation Protection and Research
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• v.45 no.4
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• pp.178-186
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• 2020

Background: Reactor pressure vessel (RV) with internals (RVI) are activated structures by neutron irradiation and volume contaminated wastes. Thus, to develop safe and optimized disposal plan for them at a disposal site, it is important to perform exact activation calculation and evaluate the dose rate on the surface of casks which contain cut-off pieces. Materials and Methods: RV and RVI are subjected to neutron activation calculation via Monte Carlo methodology with MCNP6 and ORIGEN-S program-neutron flux, isotopic specific activity, and gamma spectrum calculation on each component of RV and RVI, and dose rate evaluation with MCNP6. Results and Discussion: Through neutron activation analysis, dose rate is evaluated for the casks containing cut-off pieces produced from decommissioned RV and RVI. For RV cut-off ones, the highest value of dose rate on the surface of cask is 6.97 × 10-1 mSv/hr and 2 m from it is 3.03 × 10-2 mSv/hr. For RVI cut-off ones, on the surface of it is 0.166 × 10-1 mSv/hr and 2 m from it is 1.04 × 10-1 mSv/hr. Dose rates for various RV and RVI cut-off pieces distributed lower than the limit except the one of 2 m from the cask surface of RVI. It needs to adjust contents in cask which carries highly radioactive components in order to decrease thickness of cask. Conclusion: Two types of casks are considered in this paper: box type for very-low-level waste (VLLW) as well as low-level waste (LLW) and cylinder type for intermediate-level waste (ILW). The results will contribute to the development of optimal loading plans for RV and RVI cut-off pieces during the decommissioning of nuclear power plant that can be used to prepare radioactive waste disposal plans for the different types of wastes-ILW, LLW, and VLLW.

• Korean Journal of Environmental Biology
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• v.17 no.1
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• pp.11-15
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• 1999

To investigate the stimulating effects of the low- dose radiation, the seeds of chinese cabbages (Brassica campestris L. cv. Hanyoreum and cv. Tropic emperor) were irradiated at the dose of 0.5 Gy~20 Gy with the ${\gamma}$-ray radition. In case of ‘Hanyoreum’cultivar, there were no significant promoting effects on the germination rate except the 0.5 Gy irradiated group. The increase in seedling height and fresh weight in 8 Gy and 12 Gy irradiated groups was 20% and 40%, respectively, which suggested the stimulating effect of the low-dose radiation on the early growth. In case of‘Tropic emperor’cultivar, the germination rate of 1 Gy irradiated group increased approximately 10% and the seedling height and fresh weight of 1 Gy and 12 Gy irradiated group in the greenhouse 20% on the average, and plant height and fresh weight of 0.5 Gy and 4 Gy irradiated group in the field increased 10% and 20% on the average, respectively.

• The Korean Journal of Pain
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• v.32 no.2
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• pp.97-104
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• 2019

Background: This study was conducted to compare the effectiveness of low-dose ketamine versus ketorolac in pain control in patients with acute renal colic presenting to the emergency department (ED). Methods: This is a double-blind randomized clinical trial. The initial pain severity was assessed using the numerical rating scale (NRS). Then, ketamine or ketorolac was administered intravenously at a dose of 0.6 mg/kg and 30 mg respectively. The pain severity and adverse drug reactions were recorded 5, 15, 30, 60, and 120 min thereafter. Results: The data of 62 subjects in the ketamine group and 64 patients in the ketorolac group were analyzed. The mean age of the patients was $34.2{\pm}9.9$ and $37.9{\pm}10.6\;years$ in the ketamine and ketorolac group, respectively. There was no significant difference in the mean NRS scores at each time point, except for the 5 min, between the two groups. Despite a marked decrease in pain severity in the ketamine group from drug administration at the 5 min, a slight increase in pain was observed from the 5 min to the 15 min. The rate of adverse drug reactions, including dizziness (P = 0.001), agitation (P = 0.002), increased systolic blood pressure (> 140 mmHg), and diastolic blood pressure (> 90 mmHg) was higher in the ketamine group. Conclusions: Low dose ketamine is as effective as ketorolac in pain management in patients with renal colic presenting to the ED. However, it is associated with a higher rate of adverse drug reactions.

• Journal of radiological science and technology
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• v.39 no.4
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• pp.565-570
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• 2016

Radioactive iodine($^{131}I$) treatment reduces recurrence and increases survival in patients with differentiated thyroid cancer. However, it is important in terms of radiation safety management to measure the radiation dose rate generated from the patient because the radiation emitted from the patient may cause the exposure. Research methods, it measured radiation dose-rate according to the elapsed time from 1 m from the upper abdomen of the patient by intake of radioactive iodine. Directly comparing the changes over time, high dose rate sensitivity and efficiency is statistically significant, and higher chamber than GM counter(p<0.05). Low dose rate sensitivity and efficiency in the chamber had lower levels than gm counter, but not statistically significant(p>0.05). In this study confirmed the characteristics of calibrated ionization chamber and GM counter according to the radiation intensity during high-dose radioactive iodine therapy by measuring the accurate and rapid radiation dose rate to the patient explains, discharged patients will be reduced to worry about radiation hazard of family and others person.