• Progress in Medical Physics
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• v.20 no.4
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• pp.260-268
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• 2009

In this study, we estimated inhomogeneity correction factor in small field. And, we evaluated accuracy of treatment planning and measurement data which applied inhomogeneity correction factor or not. We developed the Inhomogeneity Correction Phantom (ICP) for insertion of inhomogeneity materials. The inhomogeneity materials were 12 types in each different electron density. This phantom is able to adapt the EBT film and 0.125 cc ion chamber for measurement of dose distribution and point dose. We evaluated comparison of planning and measurement data using ICP. When we applied to inhomogeneity correction factor or not, the average difference was 1.63% and 10.05% in each plan and film measurement data. And, the average difference of dose distribution was 10.09% in each measurement film. And the average difference of point dose was 0.43% and 2.09% in each plan and measurement data. In conclusion, if we did not apply the inhomogeneity correction factor in small field, it shows more great difference in measurement data. The planning system using this study shows good result for correction of inhomogeneity materials. In radiosurgery using small field, we should be correct the inhomogeneity correction factor, more exactly.

• Progress in Medical Physics
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• v.20 no.4
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• pp.324-330
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• 2009

In this study, we evaluated accuracy and usefulness of CyberKnife Respiratory Tracking System ($Synchrony^{TM}$, Accuray, USA) about a moving during stereotactic radiosurgery. For this study, we used moving phantom that can move the target. We also used Respiratory Tracking System called Synchrony of the Cyberknife in order to track the moving target. For treatment planning of the moving target, we obtained an image using 4D-CT. To measure dose distribution and point dose at the moving target, ion chamber (0.62 cc) and gafchromic EBT film were used. We compared dose distribution (80% isodose line of prescription dose) of static target to that of moving target in order to evaluate the accuracy of Respiratory Tracking System. We also measured the point dose at the target. The mean difference of synchronization for TLS (target localization system) and Synchrony were $11.5{\pm}3.09\;mm$ for desynchronization and $0.14{\pm}0.08\;mm$ for synchronization. The mean difference between static target plan and moving target plan using 4D CT images was $0.18{\pm}0.06\;mm$. And, the accuracy of Respiratory Tracking System was less 1 mm. Estimation of usefulness in Respiratory Tracking System was $17.39{\pm}0.14\;mm$ for inactivity and $1.37{\pm}0.11\;mm$ for activity. The mean difference of absolute dose was $0.68{\pm}0.38%$ in static target and $1.31{\pm}0.81%$ in moving target. As a conclusion, when we treat about the moving target, we consider that it is important to use 4D-CT and the Respiratory Tracking System. In this study, we confirmed the accuracy and usefulness of Respiratory Tracking System in the Cyberknife.

• Journal of Hospice and Palliative Care
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• v.20 no.3
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• pp.177-187
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• 2017

Purpose: From August 2017, hospice-palliative care (HPC) will be provided to patients with acquired immunodeficiency syndrome (AIDS), chronic obstructive pulmonary disease (COPD), and liver cirrhosis in Korea. To contribute to building a non-cancer (NC) hospice-palliative care model, NC specialists were interviewed regarding the goals, details, and provision methods of the model. Methods: Four physicians specializing in HPC of cancer patients formulated a semi-structured interview with questions extracted from literature review of 85 articles on NC HPC. Eleven NC disease specialists were interviewed, and their answers were analyzed according to the qualitative content analysis process. Results: The interviewees said as follows: It is difficult to define end-stage NC patients. HPC for cancer patients and that for NC patients share similar goals and content. However, emphasis should be placed on alleviating other physical symptoms and emotional care rather than pain control. Timing of the care provision should be when patients are diagnosed as "end stage". Special issues should be considered for each NC disease (e.g., use of anti-retroviral drugs for AIDS patients, oxygen supply for COPD patients suffering from dyspnea, liver transplantation for patients with liver cirrhosis) and education should be provided to healthcare professionals. NC patients tend to negatively perceive HPC, and the government's financial assistance is insufficient. Conclusion: It is necessary to define end-stage NC patients through in-depth discussion to minimize issues that will likely accompany the expansion of care recipients. This requires cooperation between medical staff caring for NC patients and HPC givers for cancer patients.

• Childhood Kidney Diseases
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• v.8 no.2
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• pp.129-137
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• 2004

Purpose : Nocternal enuresis is a common disorder. Tricyclic antidepressant and desmopressin have been accepted pharmacological treatment for this disorder We conducted a cooperative study to investigate the efficacy and adverse reactions of imipramine, desmopressin and combination treatment in children with primary monosymptomatic nocturnal enuresis(PMNE). Methods: Data from a large multicenter study were analysed. In the period of 8 months in 2002, the study comprised of 168 children(78 boys and 90 girls, 5 to 15 years old) with PMNE for imipramine, desmopressin or combination treatment. Before treatment a history, physical examination and laboratory tests were performed and the children were observed for 2 weeks. Response rate, adverse reactions and enuresis episodes after stopping drug administration were evaluated after 12-weeks of imipramine, desmopressin or combination of both. Results: After 4 weeks, the frequency of bed wetting in all treated patients decreased during treatment significantly Even though a 30-50%, reduction in the number of wet nights were 68.6%, 74.4% and 86.1% during 12 weeks treatment by imipramine, desmopressin and both of them respectively, there was no significant difference between them. The most common adverse reaction was decreased appetite from imipramine administration. But no serious drug-related adverse events were reported. Conclusion: Efficacy of the combination therapy of imipramine and desmopressin in PMNE appears not to be better than either drug alone. It is necessary to pay attention on account of adverse reactions during imipramine treatment even though imipramine and desmopressin were generally well tolerated.

• Pediatric Infection and Vaccine
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• v.8 no.2
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• pp.206-212
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• 2001

Objective : To determine the clinical and bacteriologic efficacy and safety of Cefprozil in acute pharyngitis and pharyngotonsilitis caused by Group A beta hemolytic streptococci in pediatric patients. Methods : Any patient of 3 to 14 age who visited the hospitals enrolled in this study with the signs and symptoms of pharyngitis or pharyngotonsilitis since July, 2000 to March, 2001, was taken throat culture and given Cefprozil(15 mg/kg/day, in two divided doses) for 10 days. 138 patients of whom showed positive culture results were followed up for the signs and symptoms during the treatment to determine clinical efficacy. Any undesirable effect was reported to determine the safety of the drug. Follow up cultures were done at the end of the study and bacteriologic efficacy was determined. Results : 138 of 256 patients who visited the hospitals with the signs and symptoms of pharyngitis or pharyngotonsilitis showed positive growth on throat culture. Mean age of the patients was $6.1{\pm}2.5$ and males and females were equally numbered. 129 of them complained fever on the first visit and 112(86.6%) of them were improved at the end of the study. Cervical lymphadenitis was seen in 58 patients and 44(75.9%) of them improved at the end of the study. Exudative pharyngitis was seen in 96 patients and 81(84.3%) of them improved. The overall clinical effcacy based on this results showed that 110(79.7%) of the patients were cured and 17(12.3%) of them improved. On the cultures and bacteriologic efficacy, 24.6% of them showed documented eradication after treatment and 62.3% of them showed presumptive eradication. Sensitivity test was done by agar dilution method and Cefprozil showed 100% sensitivity. Erythromycin, Clarithromycin and azithromycin showed 87%, 85.6 %, 90.6% sensitivity, respectively. Conclusion : Cefprozil is proved to be effective in controlling group A streptococcal pharyngitis and pharyngotonsilitis in children and showed good sensitivity. Cefprozil can be used as an effective oral cephalosporin in the patients showing penicillin hypersensitivity or patients who other drugs have failed.

• Journal of radiological science and technology
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• v.37 no.1
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• pp.7-14
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• 2014

By using a Chest Phantom(DUKE Phantom) focusing on dose reduction of diagnostic radiation field with the most use of artificial radiation, and attempt to reduce radiation dose studies technical radiation. Publisher of the main user of the X-ray Radiological technologists, Examine the effect of reducing the radiation dose to apply additional filtering of the X-ray generator. In order to understand the organ dose and effective dose by using the PC-Based Monte Carlo Program(PCXMC) Program, the patient receives, was carried out this research. In this experiment, by applying a complex filter using a copper and Al(aluminum,13) and filtered single of using only aluminum with the condition set, and measures the number of the disk of copper indicated by DUKE Phantom. The combination of the composite filtration and filtration of a single number of the disk of the copper is the same, with the PCXMC 2.0. Program looking combination of additional filtration fewest absorbed dose was calculated effective dose and organ dose. Although depends on the use mAs, The 80 kVp AP projection conditions, it is possible to reduce the effective amount of about 84 % from about 30 % to a maximum at least. The 120 kVp PA projection conditions, it is possible to reduce the effective amount of about 71 % from about 41 % to a maximum of at least. The organ dose, dose reduction rate was different in each organ, but it showed a decrease of dose rate of 30 % to up 100 % at least. Additional filtration was used on the imaging conditions throughout the study. There was no change in terms of video quality at low doses. It was found that using the DUKE Phantom and PCXMC 2.0 Program were suitable to calculate the effect of reducing the effective dose and organ dose.

• Clinical and Experimental Pediatrics
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• v.56 no.10
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• pp.439-445
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• 2013

Purpose: Previous studies suggest that the concentration of 25-hydroxyvitamin D [25(OH)D] in cord blood may show an inverse association with respiratory tract infections (RTI) during childhood. The aim of the present study was to examine the influence of 25(OH)D concentrations in cord blood on infant RTI in a Korean birth cohort. Methods: The levels of 25(OH)D in cord blood obtained from 525 Korean newborns in the prospective COhort for Childhood Origin of Asthma and allergic diseases were examined. The primary outcome variable of interest was the prevalence of RTI at 6-month follow-up, as diagnosed by pediatricians and pediatric allergy and pulmonology specialists. RTI included acute nasopharyngitis, rhinosinusitis, otitis media, croup, tracheobronchitis, bronchiolitis, and pneumonia. Results: The median concentration of 25(OH)D in cord blood was 32.0 nmol/L (interquartile range, 21.4 to 53.2). One hundred and eighty neonates (34.3%) showed 25(OH)D concentrations less than 25.0 nmol/L, 292 (55.6%) showed 25(OH)D concentrations of 25.0-74.9 nmol/L, and 53 (10.1%) showed concentrations of ${\geq}75.0$ nmol/L. Adjusting for the season of birth, multivitamin intake during pregnancy, and exposure to passive smoking during pregnancy, 25(OH)D concentrations showed an inverse association with the risk of acquiring acute nasopharyngitis by 6 months of age (P for trend=0.0004). Conclusion: The results show that 89.9% of healthy newborns in Korea are born with vitamin D insufficiency or deficiency (55.6% and 34.3%, respectively). Cord blood vitamin D insufficiency or deficiency in healthy neonates is associated with an increased risk of acute nasopharyngitis by 6 months of age. More time spent outdoors and more intensified vitamin D supplementation for pregnant women may be needed to prevent the onset of acute nasopharyngitis in infants.

• Korean Journal of Remote Sensing
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• v.32 no.2
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• pp.105-118
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• 2016

The purpose of this study is to improve the classification system of sub-divided land cover map among the land cover maps provided by the Ministry of Environment. To accomplish the purpose, first, the overseas country land cover map classification items were examined in priority. Second, the area ratio of each item established by applying the previous sub-divided classification system was analyzed. Third, the survey on the improvement of classification system targeting the users (experts and general public) who actually used the sub-divided land cover map was carried out. Fourth, a new classification system which improved the previous system by reclassifying 41 classification items into 33 items was finally established. Fifth, the established land cover classification items were applied on study area, and the land cover classification result according to the improvement method was compared with the previous classification system. Ilsan area in Goyang city where there are diverse geographic features with various land surface characteristics such as the urbanization area and agricultural land were distributed evenly were selected as the study area. The basic images used in this study were 0.25 m aerial ortho-photographs captured by the National Geographic Information Institute (NGII), and digital topographic map, detailed stock map plan, land registration map and administrative area map were used as the relevant reference data. As a result of applying the improved classification system into the study area, the area of culture-sports, leisure facilities was $1.84km^2$ which was approximately more than twice larger in comparison to the previous classification system. Other areas such as transportation and communication system and educational administration facilities were not classified. The result of this study has meaningful significance that it reflects the efficiency for the establishment and renewal of sub-divided land cover map in the future and actual users' needs.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2004.11a
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• pp.122-125
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• 2004

In radiotherapy of tumors in liver, enough planning target volume (PTV) margins are necessary to compensate breathing-related movement of tumor volumes. To overcome the problems, this study aims to obtain patients' body movements by using a moving phantom and an ultrasonic sensor, and to develop respiration gating techniques that can adjust patients' beds by using reversed values of the data obtained. The phantom made to measure patients' body movements is composed of a microprocessor (BS II, 20 MHz, 8K Byte), a sensor (Ultra-Sonic, range 3 cm ${\sim}$3 m), host computer (RS232C) and stepping motor (torque 2.3Kg) etc., and the program to control and operate it was developed. The program allows the phantom to move within the maximum range of 2 cm, its movements and corrections to take place in order, and x, y and z to move successively. After the moving phantom was adjusted by entering random movement data(three dimensional data form with distance of 2cm), and the phantom movements were acquired using the ultra sonic sensor, the two data were compared and analyzed. And then, after the movements by respiration were acquired by using guinea pigs, the real-time respiration gating techniques were drawn by operating the phantom with the reversed values of the data. The result of analyzing the acquisition-correction delay time for the three types of data values and about each value separately shows that the data values coincided with one another within 1% and that the acquisition-correction delay time was obtained real-time (2.34 ${\times}$ 10$^{-4}$sec). This study successfully confirms the clinic application possibility of respiration gating techniques by using a moving phantom and an ultra sonic sensor. With ongoing development of additional analysis system, which can be used in real-time set-up reproducibility analysis, it may be beneficially used in radiotherapy of moving tumors.

• Pediatric Infection and Vaccine
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• v.10 no.1
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• pp.95-101
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• 2003

Objective : To determine the clinical and bacteriologic efficacy and safety of Cefdinir in acute pharyngitis and pharyngotonsillitis caused by group A beta hemolytic streptococci in pediatric patients. Methods : Children aged 3 through 12 years who visited the hospitals enrolled in this study with signs and symptoms of pharyngitis or pharyngotonsillitis since May to December 2002, were taken throat culture and given Cefdinir(12 mg/kg/day, in three divided doses) for 7 days. Two hundred thirty five patients were enrolled and 90 patients who showed positive culture results were followed up for the signs and symptoms during the treatment to determine clinical efficacy. Follow-up culture were done at the end of the study and bacteriologic efficacy was determined Results : Ninety out of 235 patients who visited the hospitals with the signs and symptoms of pharyngitis showed positive growth on throat culture. Seventy nine patients were clinically and microbiologically assessable. The bacteriologic eradication rates of S. pyogenes were 100% in all the children treated with Cefdinir. Clinical cure rates were not different between less than 7 days-treated group(75%) and just 7 days-treated group(98.6%)(P=0.077). Two patients reported adverse reaction during Cefdinir treatment. Antimicrobial sensitivity of Cefdinir against S. pyogenes was 100% with range of MIC being less than 0.5 ${\mu}g/mL$. Conclusion : It seems that Cefdinir is one of reliable and well-tolerated drugs for the treatment of group A beta hemolytic streptococcal pharyngotonsillitis in children. It needs to be investigated short term efficacy in terms of improving drug compliance and impact of economic point of view. We can recognized that still high rate of the erythromycin resistant group A streptococci in our community should be monitored every year.