• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.339-346
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• 2010

The acute toxicity test of high bio-active plant essential oils was conducted with Lavender, Lemon eucalyptus and Cassia oils selected to develop environment-friendly insecticides. The results of acute oral toxicity using rats showed that $LD_{50}$ of over 2,000 mg/kg bw for Lavender, Lemon eucalyptus and Cassia oils. The calculated acute dermal $LD_{50}$ value of all testing materials was over 4,000 mg/kg bw. The Skin irritation test indicated that Lavender and Lemon eucalyptus oil have no irritation while Cassia oil has a moderate irritation. For the Eye Irritation test, the result showed no irritation for Lavender and Lemon Eucalyptus oil and irritation for Cassia oils. However, the irritation was not showed for Eye Irritationwashing test of Cassia oil. Consequently, the Lavender and Lemon eucalyptus oils were showed to be low in toxicity whereas Cassia oil indicated to cause a moderate irritation on the skin and eyes.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.490-498
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• 2010

Isotianil is a fungicide which has prevention effects against rice blast disease. In order to register this new pesticide, the series of toxicity data on animal testing were reviewed to evaluate its hazards to consumers and to determine its acceptable daily intake. Isotianil was almost excreted by urine and feces. It has low acute oral toxicity while has no skin toxicity and ocular irritation. Its skin sensitization was evaluated as slight. Genotoxicity of parent compound and metabolite was negligible. Chronic toxicity tests on rats and dogs showed changes of hematology, clinical biochemistry and liver weight. It had no reproductive and teratogenic effects. The estimation of Acceptable Daily Intake(ADI) is based on the lowest no-observed adverse effect level (NOAEL). The lowest NOAEL of 2.83 mg/kg bw/day was found in the twelve-months rats study. The NOAEL was based on increased liver weight and treatment-related effect on clinica chemistry finding at the nest higher dose level of 2.83 mg/kg bw/day. Therefore, it is considered appropriated to apply an uncertainty factor of 100 to the NOAEL 2.83 mg/kg bw/day from the rat study, resulting in an ADI of 0.028 mg/kg bw/day.

• The Journal of the Korea Contents Association
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• v.10 no.9
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• pp.309-317
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• 2010

The stainless steel wire is extensively used for the orthodontic treatment. But, the stainless steel wire that has commonly superior corrosion resistance has caused hypersensitive reaction or allergy as side effects because of corrosion in the oral environment. For improving the problem of corrosion, we was evaluated the suitability of the duplex stainless steel(DSS) as orthodontic wire through this study. The DSS wire was evaluated the mechanical strength and bio-stability for suitability and bio-compatibility as orthodontic wire. In this work, the DSS and stainless steel(SS) as common use of medical grade were prepared for the tensile strength test. The DSS wire were treated by heat. and Temperature conditions of the heat treatment were $28^{\circ}C$, $500^{\circ}C$, $600^{\circ}C$, $700^{\circ}C$, $800^{\circ}C$, $900^{\circ}C$, respectively. And the DSS wires that treated by heat on the optimum temperature condition were conducted the bending moment test and calculated the S-Max value and the modulus of elasticity. For evaluating the bio stability, each materials were conducted in vitro test for measuring the cell survival rate. The most interesting results was that the tensile strength test of SS wire($8.17\times10^4\;N/mm^2$) and DSS wire($8.05\times10^4\;N/mm^2$) that treated at $500^{\circ}C$ by heat were similar in mechanical strength. In the bio-stability study, the DSS has no cytotoxicity (p=0.05) Thus, we could make a conclusion that the duplex stainless steel wire has vastly superior corrosion resistance was suitable as orthodontic wire.

• The Journal of Pediatrics of Korean Medicine
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• v.12 no.1
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• pp.63-76
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• 1998

BACKGROUND : The purpose of this study was to investigate the new effective oriental medical treatments in pediatric diseases and its clinical applicability. METHOD : The study was composed of 1725 new patients who had been treated at the pediatric unit in the Dongguk Bun-Dang Oriental Medicine Hospital for 1 year, from 1 January 1997 to 31 December 1997, and had ages between 0 and 18 years. The chief complaint was mainly categorized by oral examination on patients and their care-givers. RESULT 1. The ratio of male to female was 1.35:1 and the number of each age group and its percentage distribution was 228 patients (13.2%) for the age group between 0 and 1 year, 746 patients (43.2%) between 2 and 6 years, and 751 patients (43.6%) for the age group over 7 years. 2. The chief complaint of the new outpatients was weakness, asthma, common cold, sinustis, skeletal disease, atopic dermatitis, stomach-ache, short stature, diarrhea, nasal blooding, night terror, allergic rhinitis, gastric disorder, enuresis, dermatitis, strabismus in the order of majority.3. The number of patients and its percentage for the most three complaints was 494 patients (28.6%) for weakness, 647 patients (37.4%) for respiratory disease, 144 patients (8.3%) for digestive disease. 4. The digestive disease tended to increase in summer, and appeared mostly in the age group between 0 and 2 years. The respiratory disease increased In inter-season and winter, but decreased significantly in summer. The age group between 1 and 5 years was the largest group of respiratory disease. CONCLUSION 1. The chief complaint in pediatric diseases that needed an oriental medical treatment was mainly the disease that tends to take long time and the weakness, and appeared frequently in digestive and respiratory diseases. 2. The oriental medical treatment was still preferred as a way to improve the weakness by patients, rather than a way to overcome their disease. In particular, the study shows that the oriental medical treatment should be emphasized in terms of preventing the disease. 3. The new diseases, which were developed with the change of human life and environment, (atopic dermatitis, enuresis, short stature, obesity, dysthymic disorder, strabismus), should be investigated as a new field of oriental medical treatment.

• Journal of Plant Biotechnology
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• v.32 no.4
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• pp.233-241
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• 2005

Plants have considerable advantages for the production of antigenic proteins because they provide an inexpensive source of protein and an easy administration of vaccine. Since a publication describing edible plant vaccine of HBsAg in 1992, a number of laboratories around the world have studied the use of plants as the bioreactor to produce antigenic proteins of human or animal pathogens. Over the last ten years, these works have been mainly focused on three major strategies for the production of antigenic proteins in plants: stable genetic transformation of either the nuclear or plastid genome, or transient expression in plants using viral vectors. As many antigenic proteins have been expressed in tobacco, also several laboratories have succeeded to express genes encoding antigenic proteins in other crop plants: potato, tomato, maize, carrot, soybean and spinach. At present many works for the production of edible plant vaccine against bacteria-mediated diseases have mostly performed the studies of enterotoxins and adhesion proteins. Also the development of new-type antigens (pili, flagella, surface protein, other enterotoxin and exotoxin etc.) is required for various targets and more efficacy to immunize against microorganism pathogens. Many works mostly studied in experimental animals had good results, and phase I clinical trial of LTB clearly indicated its immunogenic ability. On the other hand, edible plant vaccines have still problems remained to be solved. In addition to the accumulation of sufficient antigen in plants, human health, environment and agriculture regulation should be proven. Also oral tolerance, the physiological response to food antigens and commensal flora is the induction of a state of specific immunological unresponsiveness, needs to be addressed before plant-derived vaccine becomes a therapeutic option.

• The Journal of Korean Society for School & Community Health Education
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• v.2 no.2
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• pp.39-55
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• 2001

The purpose of this study was to provide the necessary fundamental data in composing a systematic text content of the public health by analyzing each text, domain, and teaching contents suggested in the textbooks as well as teachers' guides of the 7th elementary school education curriculum, while the study subjects were as follows. 1. The health education content suggested in the 7th physical education curriculum were analyzed and examined. 2. The health teaching content of each textbook in the 7th elementary school curriculum was to be analyzed and examined. In order to resolve the above research issues, the physical, spiritual, and social domain along with the (1) Proper living habit, (2) Health and nutrition, (3) Sex education, (4) Prevention of the sense-organic diseases, (5) Cleanliness of food, (6) Oral hygiene, (7) Individual health and public health, (8) Safety in living, (9) Abuse and usage of medication, educational content suggested in the 7tand (10) Environment pollution focused around the health of the elementary school education curriculum was analyzed and its outcome was as below First, compared with the 6th elementary school education curriculum, the health content suggested in the 7th elementary school education curriculum was decreased. Second, although each grade's teaching content of the health domain in the physical education was considered in its structure following after the according systems, they were preponderant in partial subjects such as the safety in living, nutrition, proper living habit, sport, and health in sport. oo. Third, the health education content was organized in 4 units such as the physical growth and development, prevention of diseases, safe living, and leisure living(leisure, spiritual health, and etc.) for the 3rd and 4th grade. Then, as for 5th and 6th grade, it was organized in 3 units such as the understanding the human body, prevention of disease, and leisure and safe living. Fourth, in the physical educational health domain, a strong point was constructed within the physical, spiritual, and social areas of the elementary school physical education. Fifth, the number of the public health education contents directly related with the health education was 43 as with 25 indirect contents. Sixth, each grade's domain unit structure of the public health content was heavy upon the physical and social area throughout every grade while in opposite, the spiritual domain' s unit structure was weak. In according to each grade, the physical domain was stressed in 4, 5, and 6 grades while the social domain was stressed in 1, 5, and 6 grades.

• Journal of dental hygiene science
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• v.14 no.4
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• pp.554-562
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• 2014

This study was conducted to identify the factors influencing toothbrushing behaviors of elementary school students by adding the variable of 'self-efficacy' to the behavioral model based on the theory of planned behavior. To collect the data for an analysis, the self-administered questionnaire was distributed to 443 students in 4th to 6th grades of elementary school placed in Inchon Metropolitan City. The statistical package of PASW 18.0 was employed for the analysis. Results of the analysis revealed that the toothbrushing intention was explained by the subjective norm (${\beta}=0.343$), the self-efficacy (${\beta}=0.171$), the perceived behavioral control (${\beta}=0.163$), and the attitude toward the tooth-brushing behavior (${\beta}=0.135$). The toothbrushing behavior was explained by the toothbrushing intention (${\beta}=0.355$) and the self-efficacy (${\beta}=0.113$). The synthesis of such results suggested that both parents and teachers in school who would be influential to students should guide elementary school students to be habituated to the right toothbrushing. Also it was estimated that the students should understand the importance of toothbrushing through proper oral health education, and they should also become confident in spontaneous toothbrushing by providing them with an environment that could help them practicing the toothbrushing easily.

• The Journal of Advanced Prosthodontics
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• v.3 no.2
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• pp.57-62
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• 2011

MATERIALS AND METHODS. Ceramics have a long history in fixed prosthodontics for achieving optimal esthetics and various materials have been used to improve ceramic core strength. However, there is a lack of information on how color is affected by fabrication procedure. The purpose of this study was to evaluate the effects of various dentin ceramic thicknesses and repeated firings on the color of zirconium oxide all-ceramic system (LavaTM) fabricated using CAD/CAM technology. MATERIALS AND METHODS. Thirty disc-shaped cores, 12 mm in diameter with a 1 mm thickness were fabricated from zirconium oxide based all ceramic systems ($Lava^{TM}$, 3M ESPE, St Paul, MN, USA) and divided into three groups (n = 10) according to veneering with dentin ceramic thicknesses: as 0.5, 1, or 1.5 mm. Repeated firings (3, 5, 7, or 9) were performed, and the color of the specimens was compared with the color after the initial firing. Color differences among ceramic specimens were measured using a spectrophotometer (VITA Easyshade, VITA Zahnfabrik, Bad $S{\ddot{a}}ckingen$, Germany) and data were expressed in CIELAB system coordinates. A repeated measures ANOVA and Bonferroni post hoc test were used to analyze the data (n = 10, ${\alpha}=.05$). RESULTS. $L^{\ast}a^{\ast}b^{\ast}$ values of the ceramic systems were affected by the number of firings (3, 5, 7, or 9 firings) (P<.001) and ceramic thickness (0.5, 1, or 1.5 mm) (P<.001). Significant interactions were present in $L^{\ast}a^{\ast}b^{\ast}$ values between the number of firings and ceramic thickness (P<.001). An increase in number of firings resulted in significant increase in $L^{\ast}$ values for both 0.5 mm and 1.5 mm thicknesses (P<.01, P=.013); however it decreased for 1 mm thickness (P<.01). The $a^{\ast}$ values increased for 1 mm and 1.5 mm thicknesses (P<.01), while it decreased for 0.5 mm specimens. The $b^{\ast}$ values increased significantly for all thicknesses (P<.01, P=.022). As the dentin ceramic thickness increased, significant reductions in $L^{\ast}$ values (P<.01) were recorded. There were significant increases in both $a^{\ast}$ and $b^{\ast}$ values (P<.01) as the dentin ceramic thickness increased. CONCLUSION. The number of firings and dentin ceramic thickness have a definite effect on the final color of all ceramic system tested. The mean ${\Delta}E$ value increased as the dentin ceramic thicknesses increased for zirconium-oxide based all ceramic specimens tested. However, the mean ${\Delta}E$ values were less than 3.7${\Delta}E$ units which is rated as a match in the oral environment.

• Journal of Periodontal and Implant Science
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• v.34 no.1
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• pp.71-81
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• 2004

Peri-implantitis could be the result of biomechanical and occlusal overload as well as microbiologic invasion. The dental implant may be more susceptible to dental plaque than the natural tooth, as the predictability of a stable soft tissue attachment complex has not yet been confirmed. With the development of peri-implantitis, the implant surface would be exposed to the oral environment and becomes coated with bacteria. The objective of therapy for this condition is to regain integration of the implant with bone. Since fibroblast adherence to surfaces is impeded by endotoxin, it would seem that decontamination would be desirable to obtain maximum osseointegration. The purpose of this study was to determine whether various chemotherapeutic and mechanical treatments(distilled water, air-powder abrasive, hypersaturated citric acid, tetracycline) can detoxify contaminated titanium implant surface by means of kinetic LAL test. Experimental rough surface titanium disks were fabricated. All of them were divided into two groups(A.a group and P.g group) and each contaminated by A. actinomycetemcomitans and P. gingivalis suspension. Contaminated disks were treated with distilled water, air-powder abrasive, citric acid and tetracycline, and then all disks were placed into LPS-free water for elution. The results were as follows : 1. In A.a group, LPS elute level of all test groups were significantly lower than control group(p<0.05). 2. In A.a group, LPS elute level of test 2, test 3 and test4 groups were significantly lower than that of control group(p<0.05). But, among the test 2, test 3, test4 groups, the significant differences were not detected. 3. In P.g group, LPS elute level of test 2, test 3 and test 4 groups were lower than that of control group(p<0.05). But, among the test groups, the significant differences were not detected. From the result of this study, it would be concluded that air-powder abrasive, hypersaturated citric acid and tetracycline treatments may be effective at reducing endotoxin level on rough titanium implant surfaces, and can be clinically used. But the treatments in peri-implantitis differentially impact osseointegration making one method clinically superior. To gain this knowledges, further molecular biologic and histopathologic studies should be developed.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.1
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• pp.146-153
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• 2001

The difference of composition of composite resin may affect the mechanical properties of composite resin and the environment is important for the properties of materials. The composite resin restoration is always exposed to fluid in oral cavity and the composite resin matrix is able to absorb water, which is accompanied by some swelling of the composite The uptake of water by composites has been correlated with decreases in surface hardness and wear resistance. The purpose of this study was to investigate the effects of water storage in $37^{\circ}C$ distilled water after 7days, 30days, 60days, 120days on compressive strength and flexural strength of dental composite resin, Z-100(group 1) Spectrum(group 2), Clearfil AP-X(group 3), Pyramid(group 4), Heliomolar(group 5). The compressive and flexural strength were measured by instron machine. The following results were obtained: 1. There were significant reduction of compressive strength as water storage time increased, 7days, 30days, 60 days, 120days(p<0.05). 2. There were significant reduction of flexural strength as water storage time increased, 7days, 30days, 60days, 120days(p<0.05). 3. Group 1, 2, 3 -hybrid type showed higher compressive and flexural strength than group 5-microfine type which had lower filler contents.