• Progress in Medical Physics
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• v.1 no.1
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• pp.75-84
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• 1990

We have claculated the absorbed dose distributions in water phantom irradiated by high energy photon beam. PDD (Percent Depth Dose) and Beam Profile can be represented by functions of depths and distances by using one dimensional model model based on transport theory. The parameters on scattering and absorption are evaluated by using non-linear regression process method. The values neeessary for calculation are obtained by simple experiment. The calculated values are in good agreement with the measured values.

• Proceedings of the Korean Society of Medical Physics Conference
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• 1999.11a
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• pp.249-252
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• 1999

• Journal of Food Hygiene and Safety
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• v.15 no.3
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• pp.267-270
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• 2000

This study was designed to predict the risk of a hazard chemical, vinyl chloride, by applying dose-response assessment that are one of the major process in practicing risk assessment. After extrapolating from the high dose exposure of vinyl chloride based upon animal carcinogenic data to the low dose exposed to human using several mathematical models, we calculated the cancer potency factors as well as virtually safe dose and the resulted values were compared. This process will provide the new insight to assess the risk of a chemical accurately imposed to human in the future.

• Journal of The Korean Society of Clinical Toxicology
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• v.8 no.1
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• pp.1-6
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• 2010

Methylene blue is a very effective reducer of drug-induced methemoglobinemia. It has dose-dependent oxidation or reduction properties. In most cases, a dose of 1 to 2 mg/kg IV given over 5 minutes and immediately followed by a 15- to 30-mL fluid flush to minimize the local pain is both effective and relatively safe. The onset of action is quite rapid, and the effects are usually seen within 30 minutes. The dose may be repeated after 30 to 60 minutes and then every 2 to 4 hours as needed. The total dose should not exceed 7 mg/kg as a single dose or 15 mg/kg within 24 hours. Repeated treatment may be needed for treating compounds that have prolonged elimination or those compounds that undergo enterohepatic recirculation (e.g., dapsone). Methylene blue can cause dose-related toxicity. At high doses, methylene blue can also induce an acute hemolytic anemia and rebound methemoglobinemia. The reasons for treatment failure with methylene blue include ineffective GI decontamination, the existence of other forms of hemoglobin (e.g., sulfhemoglobin), a low or high dose of methylene blue and the toxicokinetics of some agents, such as aniline, benzocaine or dapsone.

• Radiation Oncology Journal
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• v.5 no.2
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• pp.137-140
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• 1987

In brachytherapy of uterine conical cancer using a high dose rate remote afterloading system, it is of prime importance to deliver a accurate dose in each fractionated treatment by minimizing the difference between the pre-treatment planned and post-treatment calculated doses. The post-treatment calculated point A dose was not much different from the pretreatment planned dose (500 cGy). The $average{\pm}standard$ deviation was $500\pm18cGy$ and 84 percent of 82 intracavitary radiotherapy was within the range of $500\pm25cGy$.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.1185-1186
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• 2008

A nuclear explosion emits a transient radiation pulse like gamma rays. Gamma rays have a high energy and cause unexpected effects in semiconductor devices. These effects are mainly referred to dose-rate latcup and dose-rate upset. By transient radiation pulse in CMOS devices, dose-rate latchup is simulated in this paper.

• Journal of Medicine and Life Science
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• v.16 no.1
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• pp.31-33
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• 2019

Hypercalcemia is often seen in patients, but most of them showed mild to moderate hypercalcemia. The severe hypercalcemia with a blood calcium level of 14.0 mg/dL or more is known to be associated mainly with malignant tumors. Because this is emergency status, most clinicians tried to decrease serum calcium level to near normal range to improve symptoms related to hypercalcemia. A 71-year-old female patient visited the emergency room with dizziness and general weakness. Her serum calcium level was very high (15.6 mg/dL), but serum PTH, 25-OH vitamin D, and PTH related peptide were normal. We can exclude hyperparathyroidism, familial hypocalciuric hypercalcemia, other connective tissue diseases, and hypercalcemia due to malignant tumors as a cause of severe hypercalcemia. Conclusively, we diagnosed as severe hypercalcemia due to high-dose vitamin D injections treated one week ago. High dose vitamin D injections have recently been shown to increase the frequency of prescription as the various causes and the clinicians needed to carefully monitor the serum calcium levels in the patients after treating with high dose vitamin D.

• Journal of radiological science and technology
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• v.45 no.4
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• pp.313-320
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• 2022

Both angiography and interventional procedures accompanied by angiography provide many diagnostic and therapeutic benefits to patients and are rapidly increasing. However, unlike general radiography or computed tomography using the same X-ray, the amount of radiation is quite high, but the dose range can vary considerably for each patient and operator. The high sensitivity of the lens to radiation during cerebral angiography and neurointervention is already well known, and although there are many related studies, it is insufficient to easily reduce radiation in diagnosis and treatment. In this situation, in particular, by adding three-dimensional rotational angiography (3D-RA) to the existing two-dimensional (2D) angiography, it is now possible to make an accurate diagnosis. However, since this 3D-RA acquires images through projection of more radiation than before, the exposure dose of the lens may be higher. Therefore, we tried to analyze whether the radiation dose of the lens can be reduced by moving the lens out of the field range by adjusting the table height and magnification ratio during the examination using 3D-RA. The surface dose was measured using a rando phantom and a radiophotoluminescent glass dosimeter (PLD) and the radiation dose was compared by adjusting the table height and magnification ratio based on the central point. As a result, it was found that the radiation dose of the lens decreased as the table height increased from the central point, that is, as the lens was out of the field of view. In conclusion, in 3D-RA, moving the table position of about 2 cm in height will make a significant contribution to the dose reduction of the lens, and it was confirmed that adjusting the magnification ratio can also reduce the surface dose of the lens.

• Journal of the Korean Society of Safety
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• v.24 no.2
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• pp.100-104
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• 2009

In this study, the space gamma dose rates in the apartments structured with concrete were measured in accordance with construction year. In addition, the environmental radiation rates coming from the subway platforms and the road tunnels were analyzed in the equivalent dose by multiplying the absorbed dose with the radiation weighting factors. The space gamma dose rates measured in apartments were higher than those of outdoor which was $0.08{\sim}0.11uSv/h$ in the natural conditions. Especially, the older construction year is, the higher becomes space gamma dose rate. The average gamma dose rates in the subway platforms were measured. In the case of Busan and Daegu subway, the earlier the opening year is, the higher becomes dose rate. However, the dose rates of Seoul subway Lines were high overall, regardless of opening year. Seoul subway Line 6 showed the highest value of 0.21uSv/h. The gamma dose rate in road tunnels was higher than one of the outdoor and increased with opening year like as apartment. In dose rate comparison of the concrete structures with the outdoor, therefore, the space gamma dose rate of indoor is higher than one of the outdoor and the older structures have a higher dose rate.

• Journal of The Korean Society of Clinical Toxicology
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• v.9 no.2
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• pp.56-60
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• 2011

Purpose: The optimal dose of oximes for use in the treatment of organophosphorus pesticide poisoning has not been conclusively established. In this retrospective study, we assessed the effectiveness of the use of high-dose pralidoxime infusion in treating organophosphorus pesticide poisoning. Methods: From January 1998 to December 2009, 71 patients visited the hospital Emergency Department (ED) as a result of organophosphate pesticide intoxication. All of these patients received an initial bolus of 2 g of pralidoxime as the first step of treatment. Patients who then received continuous infusion of pralidoxime at a dose of 500 mg/hr were entered into study group 1 (low dose), and those treated by continuous infusion of pralidoxime at a dose of 1000 mg/hr were entered into study group 2 (high-dose). Plasma cholinesterase activities for each patient were evaluated at ED arrival and re-evaluated 24 hours after pralidoxime infusion. The effectiveness of the two treatment modalities was gauged by comparing the required duration of mechanical ventilation, time spent in the intensive care unit (ICU) and total time spent in the hospital. Results: The mean duration of mechanical ventilation was $9.98{\pm}6.47$ days for group 1 and $4.39{\pm}6.44$ days for group 2. The respective mean duration of time spent in ICU and the total number of days in the hospital were $16.38{\pm}18.84$ days and $21.87{\pm}20.16$ days for group 1, and $7.83{\pm}9.99$ days and $11.71{\pm}13.53$ days for group 2. Highdose pralidoxime treatment was associated with shorter required durations for mechanical ventilation, ICU and hospital stay. In addition, plasma cholinesterase reactivation rates were higher for those patients receiving high-dose pralidoxime treatment. Conclusion: The results suggest that high-dose pralidoxime treatment has greater efficacy for patients suffering from organophosphorus pesticide poisoning.