• Progress in Medical Physics
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• v.30 no.4
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• pp.104-111
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• 2019

Purpose: Online magnetic resonance-guided adaptive radiotherapy (MRgART), an emerging technique, is used to address the change in anatomical structures, such as treatment target region, during the treatment period. However, the electron density map used for dose calculation differs from that for daily treatment, owing to the variation in organ location and, notably, air pockets. In this study, we evaluate the dosimetric effect of electron density override on air pockets during online ART for pancreatic cancer cases. Methods: Five pancreatic cancer patients, who were treated with MRgART at the Seoul National University Hospital, were enrolled in the study. Intensity modulated radiation therapy plans were generated for each patient with 60Co beams on a ViewrayTM system, with a 45 Gy prescription dose for stereotactic body radiation therapy. During the treatment, the electron density map was modified based on the daily MR image. We recalculated the dose distribution on the plan, and the dosimetric parameters were obtained from the dose volume histograms of the planning target volume (PTV) and organs at risk. Results: The average dose difference in the PTV was 0.86Gy, and the observed difference at the maximum dose was up to 2.07 Gy. The variation in air pockets during treatment resulted in an under- or overdose in the PTV. Conclusions: We recommend the re-contouring of the air pockets to deliver an accurate radiation dose to the target in MRgART, even though it is a time-consuming method.

• Progress in Medical Physics
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• v.18 no.4
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• pp.187-193
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• 2007

In an effort to assess the internal absorbed dose of radionuclides that is suitable to Koreans' physiological characteristics, we asked 28 male Koreans to take $^{131}|$ orally, determined the thyroidal uptake and daily urination ratio, and assessed the absorbed dose by organ. As a result, first, 24 hours after administering, the average thyroidal uptake and the daily urination ratio registered 19.70% and 71.12%, respectively. Second, the whole body effective dose according to the thyroidal uptake calculated herein and the existing ICRP-suggested thyroidal uptake of 30% offered 1.464E-08 Sv and 2.189E-08 Sv, respectively, showing a 1.5 times difference. To evaluate the quantity of the absorbed dose of radioactive iodine, we can better reduce the error in assessing the body exposure dose by conducting measurement according to human races rather than depending on the existing ICRP data.

• The Journal of Korean Society for Radiation Therapy
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• v.23 no.1
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• pp.51-58
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• 2011

Purpose: In this study, we tried to check the usefulness of two Linear Accelerators, Clinac IX and 21EX (Varian, Palo Alto, CA), which are equipped in Ajou Medical Center. From 2008 to 2010, we evaluated the error range of Absolute Dose based on the daily output, which was measured by CHECKMATE$^{TM}$ (Sun Nuclear, Melbourne, FL). Materials and Methods: For Daily Q.A, photon beams of two linear accelerators, 21EX and IX (6 MV and 10 MV, respectively) were measured daily by using CHECKMATE$^{TM}$ just before the treatment began, while the absolute dose was measured biweekly by using water phantom. We analyzed the data of measured values from the daily Q.A and the absolute dose from 2008 to 2010 for 21EX, and from 2009 to 2010 for IX. We utilized Excel 2007 (Microsoft, USA) to evaluate Average, Standard deviation and Confidence level of the data. Furthermore, in order to check the measured values of CHECKMATE$^{TM}$ and the significance of absolute dose, each error value was compared and analyzed. Results: During the observation period, the output of two equipment's absolute dose increased in process of time and in both 6 MV and 10 MV, there was a similar increasing trend. In addition, the error rate of the measured value of CHECKMATE$^{TM}$ and the value of absolute dose were under 0.34, which means that there is a similarity relationship between the two measured values. After checking that the measured value of CHECKMATE$^{TM}$ increased, We measured the absolute dose to adjust that. When the error range was close to 2~3%, the number of changing the output was four for 21EX and three for IX. Conclusion: As a result of measuring and analyzing the daily output changes for two years by using CHECKMATE$^{TM}$, we could find that there is a significance between the output which we should obey during Q.A, and the measured value of absolute dose within the error tolerance of 2~3%. Thus, the use of CHECKMATE$^{TM}$ can be positively considered for more efficient and reliable daily output verification of linear accelerator. It can also be a good standard for other medical centers to understand the trends of linear accelerator and to refer to for the correction of each output.

• Journal of Korean Foot and Ankle Society
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• v.8 no.1
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• pp.58-63
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• 2004

Purpose: The purpose of this study is to evaluate the effectiveness of low-dose gabapentin for interdigital neuroma. Metrials and Methods: Between April 2000 and June 2003, 32 patients (39 feet) with interdigital neuroma were treated with using low-dose gabapentin. Two of the 32 patients were male, and thirty were female, and the average age was 47.4 years. The follow-up was 6 to 44months (mean 15.1 months). All cases were diagnosed by physical examination and ultrasonography or MRI. Low-dose gabapentin (300-600 mg) was prescribed and shoe modification was recommended. The patients were evaluated through questionnaire. Results: Neuroma was found in twenty one cases at the third intermetatarsal space, and thirteen at the second intermetatarsal space. The sensitivity of ultrasonography was 96% and that of MRI was 79%. Overall satisfaction was rated as excellent or good by 18 cases (57%). Average pain relief ratio was 50.3%, and in 14 cases, more than 80% of pain relief was noted. Nine (28%) of 32 patients showed they had no activity restrictions, such as daily activities or work, whereas 8 (25%) had mild restrictions and 15 (47%) had major restrictions. Twelve of 15 patient with major restrictions had been treated operatively (neurectomy; 10 cases, decompression; 2 cases). One case had gastrointestinal problem. Conclusion: Low-dose gabapentin for interdigital neuroma was one of the effective conservative treatments. The operation may be preserved for patient with the persist symptoms, nevertheless the conservative treatments and use of low-dose gabapentin.

• Journal of Radiation Protection and Research
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• v.47 no.2
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• pp.86-92
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• 2022

Background: The present study investigated the radiation dose distribution of balloon kyphoplasty (BKP) among surgeons and medical staff, and this is the first research to observe such exposure in Japan. Materials and Methods: The study subjects were an orthopedic surgeon (n = 1) and surgical staff (n = 9) who intervened in BKP surgery performed at the National Hospital Organization Disaster Medical Center (Tokyo, Japan) between March 2019 and October 2019. Only disposable protective gloves (0.022 mmPb equivalent thickness or less) and trunk protectors were used, and no protective glasses or thyroid drapes were used. Results and Discussion: The surgery time per vertebral body was 36.2 minutes, and the fluoroscopic time was 6.8 minutes. The average exposure dose per vertebral body was 1.46 mSv for the finger (70 ㎛ dose equivalent), 0.24 mSv for the lens of the eye (3 mm dose equivalent), 0.11 mSv for the neck (10 mm dose equivalent), and 0.03 mSv for the chest (10 mm dose equivalent) under the protective suit.The estimated cumulative radiation exposure dose of 23 cases of BKP was calculated to be 50.37 mSv for the fingers, 8.27 mSv for the lens, 3.91 mSv for the neck, and 1.15 mSv for the chest. Conclusion: It is important to know the exposure dose of orthopedic surgeons, implement measures for exposure reduction, and verify the safety of daily use of radiation during surgery and examination.

• Korean Journal of Clinical Pharmacy
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• v.31 no.1
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• pp.35-43
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• 2021

Background: Migraine is a common neurological disorder that affects the quality of life and causes several health problems. Preventive migraine treatment can reduce migraine frequency, headache severity, and health care costs. This study aimed to estimate the utilization of migraine preventive therapy and associated factors in eligible patients. Methods: We studied 534 patients with migraine who were eligible for migraine preventive therapy using 2017 National Patient Sample (NPS) data from the Health Insurance Review and Assessment Service (HIRA). We estimated the migraine days by calculating the monthly average number of defined daily dose (DDD) of migraine-specific acute drug. Patients with a monthly average number of DDD of 4 or more were considered as subjects for preventive treatment. Chi-square test and multiple logistic regression analysis were used to determine the association between the preventive therapy and the influencing variables. Results: Less than half of the eligible patients for prophylaxis (n=234, 43.8%) were prescribed preventive therapy. Multiple logistic regression results show that migraine preventive therapy was influenced by age, the type of migraine, and some comorbidities. Patients over the age of 50 tend to receive less prophylactic treatment than under the age of 40. On the other hand, migraine patients with epilepsy or depression were more likely to receive preventive therapy. Sumatriptan was the most preferred medication for acute treatment, and propranolol was the most commonly prescribed drug for prevention. Conclusions: More than half of the patients who were candidates for migraine prophylaxis were not receiving suitable preventive treatment. Positive factors affecting the use of migraine prevention were the presence of comorbidities such as epilepsy and depression.

• Journal of Radiation Protection and Research
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• v.32 no.2
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• pp.45-50
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• 2007

In this study, uptake rates of internal organs and daily urinary excretion rates were measured to get more reliable estimation results for Korean. Radioactive iodine($^{131}I$) of $100{\mu}Ci$ was administered by ingestion to 28 adult males for the experiment and then the radioactivity in thyroid gland, liver, stomach, small intestine, kidneys, and urine was measured after time intervals of 2, 4, 6 and 24 hours. Uptake rates of each organ and daily urinary excretion rates were calculated on the basis of these experimental results. As a result, uptake rates of 19.70% for thyroid and daily urinary excretion rates of 71.12%, on the average, were indicated. The maximum of uptake rates and daily urinary excretion rates were recorded after 2 hours of administration of $^{131}I$, but those rates were decreased gradually later. It was also found that uptake rates were the highest in stomach, followed by the left kidney, liver, small intestine and right kidney except for thyroid gland. In this experiment, the calculated uptake change rate in thyroid gland after 24 hours of administration of $^{131}I$ was different from that of ICRP-54/67(30%) and ICRP-78(25%). Thus, it is necessary to apply more reliable approach, reflecting the characteristic of Korean physiology and to obtain the basic data of results using this approach for calculation of the internal adsorbed dose. In the future, this approach can be helpful for the internal dose assessment of radiation workers in a nuclear power plant or in a hospital.

• Korean Journal of Veterinary Research
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• v.41 no.1
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• pp.29-35
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• 2001

The protective effects of egg yolk atibodies obtained from chickens immunized with fimbrial antigens from ETEC 987P were evaluated in 14 and 21 d old pigs in which ETEC diarrhea was induced. For the Exp. 1, eight early-weaned pigs($5.00{\pm}0.5kg$ average BW and 14 d average age) and eight weaned pigs($6.00{\pm}0.5kg$ average BW and 21 d average age) were used to examine influence of egg yolk antibodies on growth performance and resistance to ETEC 987P infection. Dietary treatments included 1) administered of commercial egg yolk(14 d of age; CEY14), 2) administered of egg yolk antibodies(14 d of age; EYA14), 3) administered of commercial egg yolk(21 d of age; CEY21), 4) administered of egg yolk antibodies(21 d of age; EYA21). The 14 and 21 d old pigs were challenged with 2 ml of ETEC 987P at a dose of $10^{10}\;CFU\;ml^{-1}$ per weaned pigs. Weaned pigs treated with egg yolk antibodies recovered and pigs treated with egg yolk antibodies tended to increase average daily gain(P<0.05). Also, EYA12 and EYA21 treatments were reduced coli-form bacteria concentration and increased Lactobacilli sp. concentration from feces. For the Exp. 2, sixteen weaned pigs($6.00{\pm}0.5kg$ average daily gain BW and 21 d average age) were used to examine influence of yolk or white from egg containing antibodies on growth performance and resistance to ETEC 987P infection. Dietary treatments included l) administered of commercial egg yolk(CEY), 2) administered of commercial egg white(CEW), 3) administered of egg yolk antibodies(EYA), 4) administered of egg white antibodies(EWA). Pigs treated only with EYA showed signs of recovery. Also, EYA treatment showed the best average daily gain without significant differences (P>0.05). EYA treatment was reduced coli-form bacteria concentration increased and Lactobacilli sp. concentration from feces. In conclusion, egg yolk antibodies have protective effects from pigs in which ETEC diarrhea was induced.

• Korean Journal of Poultry Science
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• v.45 no.3
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• pp.147-154
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• 2018

A total of 90 one-day-old male broilers (Ross 308) were randomly assigned to one of the three dietary treatments, each consisting of six replicates (5 broilers/cage). The dietary treatments were 1) control (CON: fresh clean water with no supplement); 2) low dose [LD: CON + 1.56% extractions from the wooden chips (EWC)] and 3) high dose (HD: CON + 12.5% EWC). Drinking water supplemented with EWC was provided using specifically designed individual nipple drinker units. Average daily water intake (ADWI), average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) were measured weekly for 21 days. One broiler from each cage was euthanized for measuring the visceral organ weights and collecting ileal tissue samples for ileal architecture analysis on day 21. Broilers assigned to the LD and HD watery groups showed higher ADWI than that in broilers consumed CON on day 7 (P<0.05). The broilers subjected to HD treatment showed a deeper crypt depth (P<0.05) than that in broilers subjected to LD and CON on day 21. Therefore, broilers consumed HD showed a lower (P<0.05) villus height:crypt depth ratio than that broilers consumed CON on day 21. Broilers provided drinking water containing any of the tested concentrations of EWC showed no effect (P > 0.05) on growth performance, ileal villus height, and visceral organ weights as compared with those in the CON from hatch to 21 days. In conclusion, broilers fed HD showed reduction in villus height:crypt depth ratio without impairing growth performance and visceral organ weights for the experimental period.

• The Journal of Korean Society for School & Community Health Education
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• v.18 no.1
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• pp.1-12
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• 2017

Objectives: This study aimed to analyze sexual experience rates according to socio-demographic factors, health behavioral factors, and internet use time, and to identify sex experience related factors in high school students using the data from the 11th Korean Youth Health Risk Behavior Web-Based Survey. Methods: A total of 33,744 students (17,346 boys and 16,398 girls) in high schools were analyzed using the SPSS WIN version 22 program. SPSS complex samples methods were used for analyses. Socio-demographic factors, health behavioral factors, and internet use time as independents variables were included. The complex samples logistic regression analyses were used to calculate the odds ratio of the sexual experience according to the socio-demographic factors, health behavioral factors and internet use time. Unweighted frequencies and percentages were represented in result tables. Results: 3.6% of girls and 9.9% of boys in high school had sexual experiences. Daily average smoking amount and daily alcohol drinking amount were a dose-response relationship with sexual experience after considering confounding factors. Students who smoke 10-19 cigarettes had 5.74 times higher risk and 20 cigarettes or more had 7.27 times higher risk of sexual experiences, comparing with non-smoking students, relatively. Likewise, students who drink soju less than 1-2 bottles and more than 2 bottles had 3.82- and 4.35 times higher chance of sexual experiences, compared with non drinking students, respectively. Conclusions: We found that there were the dose-response relationship between health behavioral characteristics and sexual experiences. Further research is needed to identify an interaction effect between smoking and drinking alcohol on sexual experiences in high school students.