• 대한소아치과학회지
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• 제51권2호
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• pp.165-175
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• 2024

This study aimed to investigate the effects of blood contamination on the Vickers hardness and the surface morphology of premixed MTA and compare them with the effects on conventional MTA. The Vickers microhardness of Endocem MTA Premixed Regular (EP) and ProRoot MTA (PM) was assessed after immersion in fetal bovine serum (FBS) and saline. Stem cells from human exfoliated deciduous teeth (SHED) were seeded on MTA after immersion in FBS, saline, and deionized water (DW). Cell adhesion patterns and surface morphology were visualized via scanning electron microscopy (SEM). The surface microhardness of EP and PM in FBS was lower than in saline. However, short-term exposure of PM to FBS did not reduce the microhardness compared to saline. Angular crystals formed in water, while rounded crystals with more air voids appeared in FBS. Favorable SHED attachment occurred in all groups. Overall, the surface hardness of EP and PM decreased after FBS exposure, although PM was less influenced. We suggest minimizing the amount of bleeding when using MTA clinically; nevertheless, PM remains an option with more expected blood contamination than EP. In summary, exposure to FBS decreased mechanical performance but allowed cell adhesion for both MTAs, with PM being more resistant to these changes.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.687-691
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• 2000

This paper reviews recent international standards related to human-related vibration and compares them to KS standards. This comparison and analysis reveals that the current direction and activity in ISO is in progress and presents logical ways of updating Korean standards in the future. Finally, the current activity of upgrading Korean standards in the Korean TC 108/SC 4 is introduced.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.209-211
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• 2002

A number of polycyclic aromatic hydrocarbons (PAHs), such as benzo［a］pyrene, are carcinogenic and thought to contribute to the overall burden of human cancer (1). PAHs are ubiquitous in the environment and humans are exposed to them via multi-pathways, e.g. air or soil of urban areas, exposure to direct or indirect tobacco smoke, and ingestion of food or water polluted by combustion effluents (2-3). (omitted)

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2006년도 Perspectives of Evironmental Health Issues in Asia-Pacific Region
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• pp.90-110
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• 2006

In the natural course of events, most human exposure to MeHg is through fish/shellfish consumption. The methylmercury exposure levels depends on the amount and species of fish/shellfish consumed daily. The developing brain in the late gestation period is known to be most vulnerable. Further, more methylmercury accumulates in the fetuses than in mothers. Therefore, efforts must be made to protect the fetuses from the risk of methylmercury, especially in populations which consume a lot of fish/shellfish.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-1
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• pp.73-73
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• 2003

The heavy metal cadmium is a xenobiotic toxicant of environmental and occupational concern and it has been classified as a human carcinogen. Inhalation of cadmium has been implicated in the development of emphysema and pulmonary fibrosis, but, the detailed mechanism by which cadmium induces adverse biological effects is not yet known. Therefore, we undertook the investigation of genes that are induced after cadmium exposure to illustrate the mechanism of cadmium toxicity. (omitted)

• 한국환경보건학회지
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• 제31권3호
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• pp.192-198
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• 2005

The occurrence of toxic cyanobacterial blooms has been reported worldwide and poses a threat to human health through drinking water exposure. The toxins they produce are highly water soluble and can leach into the water body. To eliminate any risk of drinking water exposure, removal of these toxins is essential before the water is consumed. Conventional water treatment techniques such as chlorination, if managed well, can be effectively used to remove some of these toxins, however, saxitoxin and its derivatives pose a problem. Little toxicological data are available to evaluate the real threat of these toxins.

• 한국생활과학회지
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• 제13권5호
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• pp.691-699
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• 2004

The purpose of this study was to analyze the relationship between family functioning and family violence. The SPSS 10.0 for Windows was used to analyze data obtained through 1,044 children who live in Gwangju Chonnam area. Major findings are as follows: 1. Wife abuse and child abuse showed significant difference according to family cohesion, family flexibility, and family-system types. 2. In family violence non-experience group, 'balanced family' was found in 36.2% of the sample and 'extreme family' in 7.8%. In family violence experience group, 'balanced family' was found in 12.7% of the sample and 'extreme family' in 15.4%. 3. There were significant negative correlations between family functioning and family violence. Family cohesion and family flexibility had significant negative correlation with wife abuse and child abuse.

• 한국대기환경학회지
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• 제18권4호
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• pp.327-334
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• 2002

The work presents sensitivity and uncertainty analysis of 2-compartment model for the evaluation of indoor radon pollution in a house. Effort on the development of such model is directed towards the prediction of the generation and transfer of radon in indoor air released from groundwater. The model is used to estimate a quantitative daily human exposure through inhalation of such radon based on exposure scenarios. However, prediction from the model has uncertainty propagated from uncertainties in model parameters. In order to assess how model predictions are affected by the uncertainties of model inputs, the study performs a quantitative uncertainty analysis in conjunction with the developed model. An importance analysis is performed to rank input parameters with respect to their contribution to model prediction based on the uncertainty analysis. The results obtained from this study would be used to the evaluation of human risk by inhalation associated with the indoor pollution by radon released from groundwater.

• Asian Pacific Journal of Cancer Prevention
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• 제15권18호
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• pp.7505-7513
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• 2014

Several toxic substances have been detected in plants which are responsible for animal and human diseases. Bracken fern (Pteridium aquilinum) is one example, widely distributed in many parts of the world. It is known to cause cancer in humans and other animals. In fact, man can be directly or indirectly exposed to the danger by consuming fern, contaminated water, milk, meat, and spore inhalation. Experimental studies have shown an association between bracken exposure and gastric cancer, and research has shown genotoxic and cytotoxic effects in vitro. This paper describes and reviews toxic, carcinogenic, genotoxic/cytotoxic, and immunomodulatory effects of bracken and included possible toxic agents. The chemistry of Ptaquiloside (PT) reactions is emphasized, along with bracken problems in livestock, possible pathways of exposure in man, and control for human health.

• Toxicological Research
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• 제33권3호
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• pp.233-238
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• 2017

Xylene is a cyclic hydrocarbon and an environmental pollutant. It is also used in medical technology, paints, dyes, polishes and in many industries as a solvent; therefore, an understanding of the interaction between xylene and human lymphocytes is of significant interest. Biochemical assessment was used to demonstrate that exposure of lymphocytes to xylene induces cytotoxicity (at 6 hr), generates intracellular reactive oxygen species, collapse of mitochondrial membrane potential, lysosomal injury, lipid peroxidation and depletion of glutathione (at 3 hr). The findings show that xylene triggers oxidative stress and organelle damage in lymphocytes. The results of our study suggest that the use of antioxidant, mitochondrial and lysosomal protective agents can be helpful for individuals subject to chronic exposure to xylene.