• Journal of Preventive Medicine and Public Health
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• v.37 no.3
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• pp.232-237
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• 2004

Objectives : The study was designed to test if alcohol use and alcohol-related problems among adolescent females are related to their parents' level of alcohol problems. Methods : In 2001, a stratified sample of 2077 adolescent females, grades 10-11, from twelve female-only high schools located in a large metropolitan city in the Republic of Korea completed a questionnaire about alcohol use, parental attention, and parental alcohol consumption, and other risk and protective factors. Data were analyzed with chi-square and regression analyses. Results : Nearly 63% of the student drinkers had experienced at least one to two alcohol-related problems in their lives. Two-thirds of all 2077 students indicated that at least one of their parents had an alcohol-related problem and that approximately 29% had experienced several problems. Results of random effects ordinal logistic regression analyses suggest a dose-response relationship between parental and youth alcohol-related problems. Youth who report having parents with some and many alcohol problems were 30% (Odds Ratios [OR] = 1.30; 95% Confidence Interval [CI] = 1.10 - 1.53) and 55% (OR = 1.55; 95%CI = 1.23 - 1.95) more likely to experience alcohol-related problems than youth whose parents do not have alcohol problems, respectively, after statistically adjusting for important covariates. Conclusions : This study presents evidence that alcohol-related problems among adolescent female students is highly prevalent. Also, the study findings reveal a high percentage of parents with alcohol problems, as reported by students. This study presents evidence of what might be a hidden problem among adults and youths in the Republic of Korea that merits serious attention.

• Transactions on Electrical and Electronic Materials
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• v.1 no.4
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• pp.1-6
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• 2000

The mechanical strength of silicon carbide dose nor permit the use of diffusion as a means to achieve selective doping as required by most electronic devices. While epitaxial layers may be doped during growth, ion implantation is needed to define such regions as drain and source wells, junction isolation regions, and so on. Ion activation without an annealing cap results in serious crystal damage as these activation processes must be carried out at temperatures on the order of 1600$^{\circ}C$. Ion implanted silicon carbide that is annealed in either a vacuum or argon environment usually results in a surface morphology that is highly irregular due to the out diffusion of Si atoms. We have developed and report a successful process of using silicon overpressure, provided by silane in a CAD reactor during the anneal, to prevent the destruction of the silicon carbide surface, This process has proved to be robust and has resulted in ion activation at a annealing temperature of 1600$^{\circ}C$ without degradation of the crystal surface as determined by AFM and RBS. In addition XPS was used to look at the surface and near surface chemical states for annealing temperatures of up to 1700$^{\circ}C$. The surface and near surface regions to approximately 6 nm in depth was observed to contain no free silicon or other impurities thus indicating that the process developed results in an atomically clean SiC surface and near surface region within the detection limits of the instrument(${\pm}$1 at %).

• Korean Journal of Environmental Biology
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• v.23 no.1
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• pp.21-26
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• 2005

Cell response to genotoxic agents is complex and involves the participation of different classes of genes including cell cycle control, DNA repair and apoptosis. In this report, we presented a approach to characterize the cellular functions associated with the altered transcript profiles of MCF-7 exposed to low-dose in vitro gamma-irradiation. We used the method of human 2.4 k cDNA microarrays containing apoptosis, cell cycle, chromatin, repair, stress and chromosome genes to analyze the differential gene expression characterization that were displayed by radiation-exposed cell, human breast carcinoma MCF-7 cell line, such as 4 Gy 4 hr, 8 Gy 4 hr, and 8 Gy 12 hr. Among these genes, 66 were up-regulated and 49 were down-regulated. Specific genes were concomitantly induced in the results. Cyclin dependent kinase 4 (Cdk4) is induced for starting the cell cycle. This regulation is required for a DNA damage­induced G1 arrest. In addition to, an apoptotic pathways gene Bcl-w was concomitantly induced. Mismatch repair protein homologue-l (hMLH1), a necessary component of DNA mismatch protein repair (MMR), in G2-M cell cycle checkpoint arrest. The present study provides new information on the molecular mechanism underlying the cell response to genotoxic stress, with relevance to basic and clinical research.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.3
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• pp.369-376
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• 1998

This report shows that hydroxyl radical, generated by a Fenton reaction involving adenosine $5'-diphosphate/Fe^{2+}$ complex ($5-15\;{\mu}M$) and $H_2O_2$ ($2\;{\mu}M$), induced differentiation of HL-60 cells in a dose- and time-dependent manner. This is evidenced by the increases in 12-O-tetradecanoylphorbol 13-acetate- and fMLP-stimulated superoxide production capability. The cells exposed to hydroxyl radical for defined periods (24∼96 hr) continued to differentiate even after the hydroxyl radical generating system had been removed. The differentiated cells displayed fMLP-stimulated calcium mobilization and increased expression of myeloid-specific antigen CD11b and CD14. The extent of the differentiation was markedly reduced by desferrioxamine ($100\;{\mu}M$), dimethylthiourea (5 mM), N,N'-diphenyl-1,4-phenylenediamine ($2\;{\mu}M$), and N-acetyl-L-cysteine (5 mM). The induction of differentiation by hydroxyl radical was enhanced by 3-isobutyl-1-methylxanthine ($200\;{\mu}M$) and Ro-20-1724 ($8\;{\mu}M$), and inhibited by dipyridamole (2 ${\mu}M$). These results suggest that hydroxyl radicals may induce commitment of HL-60 cells to differentiate into more mature cells of myelomonocytic lineage through specific signal-transduction pathway that is modulated by phosphodiesterase inhibitors.

• Radiation Oncology Journal
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• v.35 no.4
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• pp.325-331
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• 2017

Purpose: There is controversy regarding the cosmetic outcome after accelerated partial breast radiation (APBR). We report the cosmetic outcome from a single-arm prospective clinical trial of APBR delivered using intensity-modulated radiation therapy (IMRT) in elderly patients with stage I breast cancer (BC), using a novel fractionation schedule. Materials and Methods: Forty-two patients aged ${\geq}65$, with Stage I BC who underwent breast-conserving surgery were enrolled in a phase I/II study evaluating a 2-week course of APBR. Thirty eligible patients received 40 Gy in 4 Gy daily fractions. Cosmetic outcome was assessed subjectively by physician/patient and objectively by using a computer program (BCCT.core) before APBR, during, and after completion of the treatment. Results: The median age was 72 years, the median tumor size was 0.8 cm, and the median follow-up was 50.5 months. The 5-year locoregional control in this cohort was 97% and overall survival 87%. At the last follow-up, patients and physicians rated cosmesis as 'excellent' or 'good' in 100% and 91 %, respectively. The BCCT.core program scored the cosmesis as 'excellent' or 'good' in 87% of the patients at baseline and 81% at the last follow-up. The median $V_{50}$ (20 Gy) of the whole breast volume (WBV) was 37.2%, with the median WBV $V_{100}$ (40 Gy) of 10.9%. Conclusion: An excellent rate of tumor control was observed in this prospective trial. By using multiple assessment techniques, we are showing acceptable cosmesis, supporting the use of IMRT planned APBR with daily schedule in elderly patients with early stage BC.

• Radiation Oncology Journal
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• v.13 no.3
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• pp.267-275
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• 1995

Radiotherapy and chemotherapy can effectively control cancer but can also cause new second cancers to develop as long-term complications especially in childhood cancer. We experienced two patients with second malignant solid neoplasm who had been treated with radiation and chemotherapy for childhood cancers One female patient with rhabdomyosarcoma of the right popliteal fossa was treated with radiotherapy at total dose of 54Gy Three years and seven months later, osteosarcoma developed in the field of radiation therapy The other male patient with non-Hodgkin's lymphoma of the small bowel was treated with radiotherapy and leiomyosarcoma developed in the field of radiotherapy 18 years later. We reviewed the literature of the second malignant neoplasm in children in respect of risk factors. The risk for a second primary cancer following radiotherapy or chemotherapy emphasizes the need for life long follow-up of patients receiving such treatments, particularly patients treated for childhood cancers.

• Journal of Korean Neurosurgical Society
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• v.55 no.4
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• pp.185-189
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• 2014

Objective : General anesthesia is often preferred for endovascular coiling of intracranial aneurysm at most centers. But in the authors' hospital, it is performed under monitored anesthesia care (MAC) using dexmedetomidine. To determine the feasibility and safety of this approach, the authors reviewed our initial experience. Methods : Retrospective data was analyzed from July 2012 to November 2012. We performed coil embolization in 28 cases using this method. Among them, for statistical significance, we analyzed 12 cases in which the procedure time exceeded an hour. Vital signs were analyzed every 10 minutes. Depth of sedation was measured according to the Ramsay sedation scale and frequency of the repeated roadmap image(s) caused by movement of the patient's head during the procedure. Results : All procedures were completed without occurrence of procedure related complications. Under MAC using dexmedetomidine, vital signs of the patients were stable, no statistical significance regarding hemodynamic and respiratory parameters was observed between time points (p>0.05). Adequate sedation was achieved. Mean Ramsay sedation scale was $3.67{\pm}1.61$ (2 to 6). Repeated roadmap image(s) due to patient's factor occurred in only one case. The mean dosage of drug for adequate sedation for the procedure was $0.65{\pm}0.12mcg/kg/hr$ without loading doses. Conclusion : To the best of my knowledge, this is the first report published in English using the method of monitored anesthesia with dexmedetomidine for intracranial aneurysm coiling. Monitored anesthesia care using dexmedetomidine without loading dose for embolization of intracranial aneurysms appeared to be a safe and effective alternative to general anesthesia.

• Journal of The Geomorphological Association of Korea
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• v.24 no.3
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• pp.149-159
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• 2017

Coastal dunes have many environmental and ecological socio-economic importances; various human activities, however, have impaired their structures and functions over the years. In 2016, environmental survey on coastal sand dune was carried out to report the present status and update the coastal sand dune list in 2001. This research analyzed the survey data in terms of geomorphological and socio-economic aspects. A list of the 189 coastal sand dune and information was updated by province. A 36.5% reduction in coastal sand dune area have been identified for using agricultural land, development area since the approximately 1940-50s. Development area in coastal sand dune covered small area as 5%, the use intensity was relatively hard. Furthermore, the difference by province also showed. Approximately 80% of the development area was concentrated in 20% of total sand dune several sand dune. It is generally accepted that coastal sand dunes were exposed high development pressure. However the result means that the general brief dose not apply for all sand dune. Therefore, characteristics of each sand dune should be analyzed and concerned the diverse management plans.

• Journal of Ginseng Research
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• v.19 no.2
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• pp.87-92
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• 1995

We conducted a prospective cohort study to evaluate the preventive effect of ginseng on the development of cancer in the population over 40 years old residing in Kangwha-eup from August 1987 to December 1992. Alnong 4, 634 persons (2, 362 men, 2, 272 women), 335 (7.6%) persons had died. Cancer accounted for 79 (22.8%) of the total death. Of 4, 634 persons eligible for analysis, 70.475 (3, 263) were ginseng intakes. Ginseng intakes had a decreased risk (RR=0.48, 95% Cl : 0.34~0.67) compared with non-intakes. The relative risk of cancer according to the kind of ginseng was 0.23 (95% Cl : 0.08~ 0.63) for fresh ginseng extract intakes. There was a decrease in risk with rising the frequency of ginseng intake, showing statistically significant dose-response relationship. The longer the duration of ginseng intake or the greater the total number of ginseng consumed, the lower the risk. Newly diagnosed cancer cases have been identified: 42 stomach, 24 lung, 14 liver and 57 at other sites. The relative risks of ginseng intakes were 0.34 (95% Cl 0.19~0.60) in gastric cancer and 0.27 (95% Cl : 0.12-0.60) in lung cancer. Among ginseng preparations, fresh ginseng intakes were significantly associated with the decreased risk of gastric cancer (RR: 0.19, 95% Cl : 0.04~0.98). These results strongly revealed that Panax Ginseng C.A. Meyer (Korean ginseng) has preventive effect against cancer.

• Safety and Health at Work
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• v.12 no.4
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• pp.445-451
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• 2021

Background: This study aimed to evaluate the reliability and validity of the self-administered questionnaire for Korean radiation workers. Methods: From May 24, 2016, to June 30, 2017, 20,608 participants completed the questionnaire, providing information on sociodemographics, lifestyle, work history and practices, medical radiation exposure, and medical history, which was linked to the National Dose Registry and the National Cancer Registry. The validity of the questionnaire was evaluated using the responses of 20,608 workers, and reliability was evaluated using the responses of 3043 workers who responded to the survey twice. Results: Responses concerning demographic characteristics and lifestyle showed reliability with a moderate-to-high agreement (kappa: 0.43-0.99), whereas responses concerning occupation and medical radiation exposure had a wide range of agreement (kappa: 0.05-0.95), possibly owing to temporal variability during employment. Regarding validity, responses to the question about the first year of employment had an excellent agreement with the national registry (intraclass correlation coefficient = 0.9); however, responses on cancer history had a wide range of agreement (kappa: 0.22-0.85). Conclusion: Although the reliability and validity of the questionnaire were not distinguished by demographic characteristics, they tended to be low among participants whose occupational radiation exposure was minimal. Overall, the information collected can be reliable for epidemiological studies; however, caution must be exercised when using information such as medical exposure and work practices, which are prone to temporal variability.