• Journal of Preventive Medicine and Public Health
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• v.37 no.4
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• pp.373-380
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• 2004

Objectives : There has been gradually increasing concern about the adverse health effects of electromagnetic radiation originating from cell phones which are widely used in modern life. Cell phone radiation may affect human health by increasing free radicals of human blood cells. This study has been designed to identify DNA damage of blood cells by electromagnetic radiation caused by cell phone use. Methods : This study investigated the health effect of acute exposure to commercially available cell phones on certain parameters such as an indicator of DNA damage for 14 healthy adult volunteers. Each volunteer during the experiment talked over the cell phone with the keypad facing the right side of the face for 4 hours. The single cell gel electrophoresis assay (Comet assay), which is very sensitive in detecting the presence of DNA strand-breaks and alkali-labile damage in individual cells, was used to assess peripheral blood cells (T-cells, B-cells, granulocytes) from volunteers before and after exposure to cell phone radiation. The parameters of Comet assay measured were Olive Tail Moment and Tail DNA %. Results : The Olive Tail Moment of B-cells and granulocytes and Tail DNA % of B-cells and granulocytes were increased by a statistically significant extent after 4-hour use of a cell phone compared with controls. Conclusion : It is concluded that cell phone radiation caused the DNA damage during the 4 hours of experimental condition. Nonetheless, this study suggested that cell phone use may increase DNA damage by electromagnetic radiation and other contributing factors.

• Survey Research
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• v.12 no.2
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• pp.145-157
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• 2011

There are limitations as to how internet surveys can be used. Applying various weighting procedures has not always resulted in error reduction. A good reference survey would increase the effects of the weighting method, but it is very difficult to get a reference survey for non-demographic weighting variables, which restricts the use of internet surveys. We hypothesized that time use variables could be employed as weighting variables. The time use survey is conducted regularly by KOSTAT and includes various time-related variables. We tested our hypothesis using the 2009 survey results, which had been gathered by KOSTAT in 2009. When we applied weighting variables which were based on the 2004 time use survey results to the online version of the 2009 KOSTAT social survey, the gap between the online and off-line versions was slightly reduced. This result shows that we could use time use survey results to develop a better weighting scheme.

• Annual Conference on Human and Language Technology
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• 2000.10d
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• pp.405-410
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• 2000

본 연구에서는 기능적 자기공명영상을 이용하여 한글 문장의 의미와 통사 처리에 관한 뇌의 활성화 양상을 비교함으로써 한글문장 이해의 과정에 대한 신경해부학적 증거를 찾고자 하였다. 6명의 자원자를 대상으로 문장진위판단과제를 이용하여 활성화를 유도하였다. 1.5T 초전도 자기공명영상 장치에서 EPI로 BOLD 기법을 이용하여 기능적 영상을 얻었으며 영상 후 처리는 SPM99 분석 프로그램을 이용하였다. 의미관련 통사관련 문장 모두에서 좌 우 전두회(frontal gyrus) 영역에서 활성화되었다. 의미와 통사처리 영역을 구분하기 위하여 감산법을 적용한 결과, 의미처리는 좌반구의 중측두회(middle temporal gyrus) 영역에서, 통사처리는 우반구의 하전두회(BA44) 부위에서 더 많이 활성화되었다. 의미처리에서 더 우세한 성향을 띠는 부위로 밝혀진 중측두회 영역은 의미처리시에 활성화되는 영역으로 보고하는 기존의 연구와 일치하는 결과이다. 의미와 통사 문장처리시의 뇌 활성화 양상은 뇌의 여러 영역에서 중첩되어 있기는 하지만, 특정영역에서의 차이를 보이고 있으므로, 의미와 통사처리는 다른 기전(mechanism)에 의해서 일어남을 시사해 준다.

• The Korean Journal of Pain
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• v.21 no.2
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• pp.126-130
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• 2008

Background: Females generally have a lower pain and temporal summation threshold than men. However, the results of studies designed to evaluate gender differences in the thresholds of heat pain and the temporal summation have been inconsistent. Newly developed device, CHEPS (Contact Heat Evoked Potential Stimulation) model of PATHWAY, have superiority on its fast rise and return time in temperature. Therefore we investigated gender differences in heat pain and temporal summation threshold. Methods: Forty healthy volunteers (20 males and 20 females) were enrolled in this study. A thermode was applied to the volar side of each volunteer's left forearm and heat pain and the temporal summation threshold was then measured. The heat pain threshold was estimated using the staircase method by starting from $36^{\circ}C$ and then increasing the temperature in $0.5^{\circ}C$ increments. The temporal summation threshold was estimated by applying five successive stimulation of the same temperature starting at $2^{\circ}C$ lower than the heat pain threshold and then increasing the temperature in $0.5^{\circ}C$ increments. Results: The mean heat pain thresholds was found to be $41.63{\pm}1.63^{\circ}C$ for males and $41.60{\pm}1.84^{\circ}C$ for females and the temporal summation thresholds were found to be $40.83{\pm}1.64^{\circ}C$ for males and $40.77{\pm}1.93^{\circ}C$ for females. The differences between males and females were not statistically significant. Conclusions: The result of this study suggested that there are no gender differences in heat pain and temporal summation threshold.

• Journal of Preventive Medicine and Public Health
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• v.39 no.1
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• pp.53-58
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• 2006

Objectives: We wanted to evaluate the main route of exposure to lead and cadmium for the general population in Korea by using multi-route and multi-media exposure assessment Methods: Samples of air at the homes, samples of the food and water and peripheral blood samples were collected from thirty volunteers living in Seoul (the metropolitan area), Yong-in (the suburban area) and Ansan (the industrial area) in 2001. Graphite furnace atomic absorption spectrometric methods were used for the determination of the Pb and Cd levels in the air, food, water and blood samples. Results: The average intake of lead through the air, drinking water and food were $5.06{\mu}g/day\;(26.3%)\;0.002{\mu}g/day\;(0.1%),\;and\;16.4{\mu}g/day\;(73.6%)$, respectively. The average intake of cadmium through the air, drinking water and food were $0.082{\mu}g/day\;(0.9%),\;0.001{\mu}g/day\;(0.007%),\;and\;12.61 {\mu}g/day\;(99.0%)$, respectively. The blood lead level was statistically higher in the male subjects than in the female subjects (3.39 and $2.22{\mu}g/dl$, respectively), and only gender was a significant variable on the multiple regression analysis for blood lead. Conclusions: This study showed that the intake of lead and cadmium through food was the major route of exposure. A policy to reduce the pollutants according to the exposure routes should be established. However, more studies will be needed to support these data for the general population.

• 한국노년학
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• v.29 no.3
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• pp.823-835
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• 2009

This study was designed to examine the effects of 12 weeks of circuit exercise on obesity, physical fitness and metabolic syndrome index in elderly obese women. 19 elderly obese women volunteered to participate in and completed the study. Participants went through their exercise program for 30 minutes per session and 3 sessions per week for 12 weeks. Lower(p<.001) and upper extremities strength(p<.05), upper(p<.05) and lower extremities flexibility(p<.01), agility & dynamic balance(p<.001), endurance exercise capacity(p<.05) were significantly increased after 12 weeks circuit training. Also, Body weight(p<.001), BMI(p<.001) & Metabolic syndrome index as waist circumference(p<.01), systolic BP(p<.05), TG(p<.001), HDL-C(p<.01), glucose(p<.05) were significantly differenced between pre and post. It was concluded that circuit exercise program has positive effects on body composition, physical fitness and metabolic syndrome index in elderly obese women.

• The Korean Journal of Nuclear Medicine
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• v.37 no.6
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• pp.364-373
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• 2003

Purpose: For good quality of myocardial perfusion images, an approximately 30 min to 1 hour of waiting time after radiopharmaceutical injection and ingestion of fatty meal are asked of the patients. The aim of this study was to investigate the shortening of waiting time after radiopharmaceutical injection and improvement of image quality using natural plant extracts that promote bile excretion. Materials and Methods: Ten volunteers participated in protocol 1 (7 men, 3 women; mean age, $24.1{\pm}2.4$ years) and protocol 2 (8 men, 2 women; mean age, $26.1{\pm}2.9$ years), respectively. For the modified method of both protocols, subjects took natural plant extracts 15 minutes before the first injection of $^{99m}Tc$ MIBI without laking fatty meals. Control (Conventional) methods were peformed with intake of a fatty meal 20 to 30 minutes after $^{99m}Tc$ MIBI injection. Results: As the results of protocol 1 and 2, the ratio of myocardial to lung ratio were not different between modified and conventional method. Liver to lung ratio of modified method showed significantly lower value than that of conventional method. In modified method, myocardial to liver ratio was higher persistently. In protocol 2, natural plant extracts took before the first injection of $^{99m}Tc$ MIBI exerted accelerating effect of excretion of bile juice into Intestine until the end of examination. Conclusion: These results represent that natural plant extracts for facilitation of bile excretion before injection of $^{99m}Tc$ MIBI may provide better quality of myocardial perfusion images without the need for preparations such as ingestion of fatty meal within the 2 hours compared with conventional method.

• Journal of Nutrition and Health
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• v.42 no.6
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• pp.516-522
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• 2009

In this study, the effects of a mixture consisting of vitamin E, vitamin C, pycnogenol and evening primrose oil (mixture LGNC-5) on ultraviolet light (UV) induced pigmentation and wrinkle reductions of normal healthy volunteers were studied. In a double-blind placebo-controlled study, each of 54 subjects took daily either 4 capsules of the mixture LGNC-5 (Group ABC; 282.5 mg/capsule) or placebo (Group Ganada). We irradiated 2.5 MED UV on the upper arms and measured the whitening effect by colorimeter-based L value. The level of wrinkle reduction was determined by image analysis using skin replica around the crow' feet, and the level of serum vitamin E was determined at baseline and 12 weeks. After 12-week oral administration, the treated group showed a significant reduction in skin pigmentation and wrinkles compared with the placebo group (p = 0.011 and p = 0.000005, respectively). Also, the level of serum vitamin E was significantly increased in the treated group after 12-week oral adminstration of the mixture compared with that in the placebo group (p = 0.0001). In conclusion, 12-week oral administration of LGNC-5 as a dietary supplement could be effective to reduce both UV induced pigmentation and skin wrinkle without side effects.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.858-868
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• 2008

This study was carried out to investigate the effects of Gastrodiae Rhizoma powder on plasma lipid profiles in elderly volunteers with hyperlipidemia, hypertension, diabetes or heart disease. 32 elderly people, 11 males and 21 females aged $60{\sim}77$ years, were given Gastrodiae Rhizoma powder 15 g twice daily for 6 months. We investigated the antheropometric data, general characteristics and dietary habit by using questionnaires. Fasting blood samples were collected from the subjects before and after this 6 months intervention study. Blood pressure, glucose, hemoglobin and lipid levels of plasma, atherogenic index (AI) and cardiac risk factors (CRF, LHR, HTR) were determined before and after consumption of Gastrodiae Rhizoma powder. The mean body mass index (BMI) of the male and female subjects were 22.4 and 23.6, respectively. The percent of ideal body weight (PIBW) of males and females were 105.6% and 122.3%, respectively. The subjects had decreased intake frequency of fish and meat in their dietary habit. After consumption of Gastrodiae Rhizoma powder, there were no significant differences in blood pressure; however, the blood glucose significantly decreased with Gastrodiae Rhizoma intake in the males. In the subjects, the levels of plasma total cholesterol, triglyceride, and LDL-cholesterol were decreased by the consumption of Gastrodiae Rhizoma powder; while the levels of plasma LDL-cholesterol was significantly decreased in female. Blood pressure and biochemical assessment (blood glucose, hemoglobin, triglyceride, total cholesterol, LDL and HDL-cholesterol) of the subjects were within the normal range. It was found that AI, CRF and LHR were significantly decreased by Gastrodiae Rhizoma intake. The present results indicate that dietary supplementation of Gastrodiae Rhizoma improved lipid metabolism and cardiac risk factor in cardiovascular disease.

• Analytical Science and Technology
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• v.12 no.5
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• pp.408-414
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• 1999

A selective and sensitive method for the derivatization of total homocysteine (Hcy) and the related compounds in plasma by gas chromatograph (GC)-electron capture detector (ECD) has been developed. To determine total homocysteine, cysteine (Cys), and methionine (Met) in human plasma using GC-ECD, analytes were reduced and converted into their N(O,S)-ethylearbonyl pentafluoropropyl (PFP) ester by derivatization with ethyl chloroformate and pentafluoropropyl alcohol (PFP-OH) in plasma. The best derivatizing agent N(O,S)-ethyl carbonyl PFP ester, was chosen by comparing the sensitivity of derivatized analysis in GC-ECD. The derivatized analytes in plasma were extracted by chloroform, and subsequently back-extracted with hexane and analyzed by GC-ECD. The calibration carves ($R^2$ > 0.990) were linear over the range $5-50{\mu}mol/L$ of Hcy and Met, $40-400{\mu}mol/L$ of Cys spiked in plasma. The detection limit observed by the established method was below $0.5{\mu}mol/L$. This method is highly sensitive and specific in the analysis of Hcy, Cys, and Met. Therefore, we suggest that this method is appropriate in the analysis of trace concentration of Hcy, Cys, and Met in biological fluids.