• Journal of Preventive Medicine and Public Health
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• 제40권3호
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• pp.218-226
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• 2007

Objectives : This study examined the relationship of parent-related negative life events with mental health and delinquent behaviors among Korean adolescents. Methods : A total of 2,976 high school first-grade pupils (1,498 boys & 1,478 girls) taking part in the third wave of Korean Youth Panel Survey completed a self-administered questionnaire regarding parent-related life events, depressive feelings, suicidal ideation, delinquent behaviors, demographic characteristics, parental socioeconomic status, social support, and social capital. Data analyses were conducted using multivariate logistic regression. Results : After adjusting for all covariates, the more parent-related negative life events adolescents experienced throughout their whole life, the more likely adolescent were to have mental and behavioral problems. A significant dose-response relationship between them was more clearly observed in girls than in boys. The experience of parentrelated negative events during childhood was significantly associated with suicidal ideation and delinquent behaviors for boys, and with depressive feelings for girls during adolescence. Indeed, parental social support, social capital, and having a close friend with delinquent behaviors, especially for girls, partially mediated the relationship between parent-related negative life events and both outcomes. Conclusions : The study showed a clear dose-response relationship of frequency of parent-related negative life events with poor mental and behavioral health for both genders. The residual effect of being exposed to parent-related events during childhood on mental health and delinquent behaviors during adolescence still remained.

• Journal of Preventive Medicine and Public Health
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• 제16권1호
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• pp.79-88
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• 1983

There has been some evidence concerning the fact that trihalomethanes(THMs), toxic chlorinated compounds, may be present in drinking water. One of the important methodologies to evaluate the toxicity of THMs is to determine enzyme alteration in experimental animal tissues after treatment. This study was intended to investigate how lactic dehydrogenase(LDH) of rat tissues is affected by administration of chloroform($CHCl_3$) and dichloromonobromomethane($CHCl_2\;Br$). THMs, high dose(1/10 LD50) or low dose(1/50 LD50) of $CHCl_3$ or $CHCl_{2}Br$ were administered orally to experimental rats for 4 or 8 weeks. The treated groups of rats were sacrificed to determine LDH specific activity and isozyme pattern in various organs which were liver, thigh muscle, kidney and brain. The conclusions were obtained as follows: 1. Alteration of LDH activities and isozyme patterns were revealed before morphologic changes in tissues. 2. The LDH specific activities were increased significantly in liver and brain after administration of high concentrations of $CHCl_3$ and $CHCl_{2}Br$ for 4 weeks respectively. Otherwise, they were decreased significantly in liver, muscle and kidney after administration for 8 weeks. 3. The isozyme activities of LDH-4 and LDH-5 were increased in muscle, brain, and especially the liver. 4. It was more distinct for the decrement of LDH H-type isozyme than the increment of M-type isozyme in muscle.

• 한국방사선학회논문지
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• 제14권2호
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• pp.169-178
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• 2020

국민의 의료수준 향상으로 CT 검사건수는 매년 증가되고 있는 추세이며, 이에 따라 연간 의료 방사선에 의한 피폭선량 또한 증가되고 있다. 이에 본 연구에서는 CT 부위별 검사 시 노출되는 인체의 유효선량을 평가하고, 이로 인한 생애 암 귀속 위험도를 추정하고자 한다. 첫 번째로, CT 진단참고수준 가이드라인에서 제시하는 부위 중 5가지를 선정하였으며, CT 장치를 통해 각 검사 부위별로 노출되는 인체의 유효선량을 평가하였다. 두 번째로, 동일한 조건 내 ALARA-CT 프로그램을 이용하여 인체 장기 및 유효선량을 산정하였으며, 국내 DRL 수준과 비교하여 검사 프로토콜에 대한 적정성을 평가하였다. 세 번째로, CT 검사 시 노출되는 유효선량에 의한 생애 암 귀속 위험도(LAR)을 추정하였다. 그 결과, 검사 중 복부 다중시기 검사 시 21.18 mSv로 가장 높은 유효선량을 나타내었으며, 복부검사를 제외한 나머지 검사에서는 DRL 이하의 선량수준을 나타내었다. 동일한 조건 내 선량계산 프로그램을 이용한 유효선량 평가 결과, 각 검사별로 약 1.1 ~ 1.9배 이상 높은 결과를 나타내었으며, 장기선량의 경우 검사 부위에 근접한 장기일수록 산란선에 의해 높은 영향을 나타내었다. CT 검사 시 성인의 생애 암 귀속 위험도의 경우, 연령이 증가함에 따라 점차적으로 감소되는 양상을 보였으며, 성별에 따라 다소 상이한 결과를 나타내었다.

• Journal of Preventive Medicine and Public Health
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• 제38권4호
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• pp.431-436
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• 2005

Objectives : We investigated the seroprevalence of the measles antibody and its at tributable factors for the students who underwent routine 2-dose Schedule Era. Methods : The subjects were 996 students of the national measles seroepidemiologic study in December 2000 who had vaccination records. We conducted a questionnaire survey and we performed serologic testing for the measlesspecific IgG by using an enzyme linked immunosorbent assay. Results : The coverage for the first dose of the MMR vaccination at 12-15 months of age was 95.1% and the coverage for the second dose of MMR at 4-6 years of age was 35.0%. The proportion of subjects undergoing 2-dosesof MMR dec reased as the age of the subjects increased. The seropositive rate of the measles antibody was significantly high in the second dose vaccinees (93.5% in the second dose group, 84.7% in the non-second dose group, p<0.001) and it was 72.0% in the 0-dose group, 85.4% in the 1-dose group and 93.7% in the 2-dose group (p<0.001). Two point eight percent of the subjects had a past history of measles infection. On the multiple logistic regression analysis, the first and second dose (odds ratio, 8.54; 95% CI.=3.05-23.91), the first dose (odds ratio, 3.06; 95% CI.=1.20-7.81) and the outbreak in the year 2000 (odds ratio, 1.89; 95% CI.=1.24-2.88) were the significant factors for the seropositivity. Conclusions : Maintaining high coverage with a 2-dose vaccination program would be the decisive factor to prevent an outbreak of measles and to eliminate measles in Korea.

• 방사선산업학회지
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• 제17권2호
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• pp.161-172
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• 2023

Coal-fired power plants handle large quantities of coal, one of the most prominent NORM, and the coal ash produced after the coal is burned can be tens of times more radioactive than the coal. Workers in these industries may be exposed to internal exposure by inhalation of particles while handling NORM. This study evaluated the size, concentration, particle shape and density, and radioactivity concentrations of airborne suspended particles in the main processes of a coal-fired power plant. Finally, the internal radiation dose to workers from particle inhalation was evaluated. For this purpose, airborne particles were collected by size using a multi-stage particle collector to determine the size, shape, and concentration of particles. Samples of coal and coal ash were collected to measure the density and radioactivity of particles. The dose conversion factor and annual radionuclide inhalation amount were derived based on the characteristics of the particles. Finally, the internal radiation dose due to particle inhalation was evaluated. Overall, the internal radiation dose to workers in the main processes of coalfired power plants A and B ranged from 1.47×10^-5~1.12×10^-3 mSv y^-1. Due to the effect of dust generated during loading operations, the internal radiation dose of fly ash loading processes in both coal-fired power plants A and B was higher than that of other processes. In the case of workers in the coal storage yard at power plants A and B, the characteristic values such as particle size, airborne concentration, and working time were the same, but due to the difference in radioactivity concentration and density depending on the origin of the coal, the internal radiation dose by origin was different, and the highest was found when inhaling coal imported from Australia among the five origins. In addition, the main nuclide contributing the most to the internal radiation dose from the main processes in the coal-fired power plants was thorium due to differences in dose conversion factors. However, considering the external radiation dose of workers in coal-fired power plants presented in overseas research cases, the annual effective dose of workers in the main processes of power plants A and B does not exceed 1mSv y^-1, which is the dose limit for the general public notified by the Nuclear Safety Act. The results of this study can be utilized to identify the internal exposure levels of workers in domestic coal-fired power plants and will contribute to the establishment of a data base for a differential safety management system for NORM-handling industries in the future.

• Journal of Radiation Protection and Research
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• 제29권4호
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• pp.243-249
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• 2004

본 연구는 소핵분석과 염색체 1번 및 4번의 DNA probe를 이용한 FISH 기법을 병행하여 방사선에 의한 소핵과 이수성에 관여하는 각 염색체의 감수성을 평가하고자 하였다. 방사선 선량에 따라 소핵의 빈도는 증가하였으며 염색체 1번과 4번의 이수성도 대조군, 1 Gy 및 2 Gy 에서 각각 2000개의 BN세포 당 9개, 47개 및 71개로 유의하게 증가하였다. 염색체 1번의 이수성 빈도는 4번에 비해 높게 관찰되었다. 염색체 1번 및 4번을 포함하는 소핵도 방사선의 선량에 따라 증가하였으며, 소핵내 염색체 1번의 포함빈도가 4번보다 높게 관찰되었다. 또한 방사선에 의한 소핵 중 낮은 빈도의 염색체 signal를 포함하는 소핵이 관찰됨으로써 방사선에 의한 소핵은 대부분 절단에 의한 것임을 확인할 수 있었다. 따라서 본 연구 결과 방사선은 이수성을 유도하며 이에 염색체가 다르게 관여할 수 있음을 보여준다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.2323-2328
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• 2014

Background: Epidemiological findings are controversial relating to the relationship between dietary folate intake and the risk of breast cancer. We therefore conducted a meta-analysis of prospective cohort studies to clarify this association. Materials and Methods: PUBMED, EMBASE, and MEDLINE databases were searched for all relevant literature published in English from January 1, 1966 to August 2013. Summary relative risk (RR) and 95% confidence intervals (CIs) were calculated using a fixed or random effects model. Results: Dietary folate intake was not significantly associated with the risk of breast cancer. The combined RR with 95%CI for the highest vs. lowest category dietary intake of folate [fifteen studies; 1,836,566 participants and 24,083 patients with breast cancer] was 0.98 (0.90-1.05). Among subgroup analysis by menstrual status, hormonal status and the consumption of alcohol, methionine and vitamin B12, no significant association was observed for the dietary intake of folate and the risk of breast cancer. Dose-response analysis showed that a 220 ${\mu}g/day$ increment in dietary folate intake was not associated with the risk of breast cancer. Conclusions: Our findings indicate that dietary folate intake has no significant effect on the risk of breast cancer.

• Asian Pacific Journal of Cancer Prevention
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• 제15권13호
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• pp.5293-5298
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• 2014

To investigate the association between salt processed food and gastric cancer, a hospital based case-control study was conducted in a high risk area of China. One hundred and seven newly diagnosed cases with histological confirmation of gastric cancer and 209 controls were recruited. Information on dietary intake was collected with a validated food frequency questionnaire. Unconditional logistic regression was applied to estimate the odds ratios with adjustment for other potential confounders. Comparing the high intake group with never consumption of salt processed foods, salted meat, pickled vegetables and preserved vegetables were significantly associated with increased risk of gastric cancer. Meanwhile, salt taste preference in diet showed a dose-response relationship with gastric cancer. Our results suggest that consumption of salted meat, pickled and preserved vegetables, are positively associated with gastric cancer. Reduction of salt and salt processed food in diets might be one practical measure to preventing gastric cancer.

• 한국환경보건학회지
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• 제31권4호
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• pp.254-259
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• 2005

Permethrin, a synthetic pyrethroid insecticide, has been widely used to protect domestic animals and the public health, as well as in agriculture against a variety of pests, which provides potential for environmental exposure. Permethrin is classified as possible human carcinogen and endocrine disrupting chemical by many international authorities. However, its developmental effects have been rarely studied. This study investigated the effects of permethrin during embryo-genesis. Developmental toxicity of permethrin was evaluated using short-term in vitro battery system. Gestation day 9.5 rat embryos (organogenesis) were cultured with permethrin (0.1,0.4 and 0.8 mg/ml) for 48 hours using whole embryo culture system. All the treatments exhibited significant decreases in the total morphological score. Permethrin induced significant growth retardation and the developmental abnormality at doses of 0.4 and 0.8 mg/ml. Moreover, the DNA and protein contents of embryos decreased in dose-dependent manner. These observations suggest that permethrin contributes to toxicity on embryonic developments in rats.

• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 2002년도 춘계학술발표대회 및 심포지움
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• pp.216-216
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• 2002

Generally, tobacco smoking has noxious effects such as DNA damage, lung cancer induction, coronary artery disease. Nowadays, as concerns on health and longevity increases, a huge variety of products that aim to assist to quit smoking or reduce addictive symptoms such as nicotine patches are developed and manufactured with safely evaluation, but the safety of the most recent products of interest which do not contain tobacco and nicotine, and shape cigarettes is not evaluated and guaranteed relatively. In this study, we used H-menthol(nicotine free-tobacco fine) which are widely consumed through the world to evaluate the single and repeated dose inhalation toxicity and genotoxicity of H menthol (Nicotine free-tobacco free) herbal cigarettes provided by Cigastop Ltd. in ICR mice.