• Journal of Periodontal and Implant Science
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• v.29 no.3
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• pp.561-578
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• 1999

The goal of periodontal therapy is the periodontal regeneration by the removal of microorganisms and their toxic products from the periodontally diseased root surface. To achieve periodontal regeneration, root conditioning as an adjunct to root planing has been done. There are low pH etchants such as citric acid, tetracycline-HCl, and EDTA solution which is a neutral chelating agent. The purpose of present study was to examine the effect of root conditioning by citric acid, tetracycline HCl, and EDTA. Total 35 root specimens(6${\times}$3${\times}$2mm) were prepared from the periodontally diseased teeth, scaled and root planed. The specimens were treated with normal saline for 1 minute, saturated citric acid(pH 1) for 3 minutes, 50mg/ml tetracycline-HCl(pH 2) for 5 minutes, 15% EDTA(pH 7) for 5 minutes using rubbing technique. The specimens were examined under scanning electron microscopy at 1000, and 3000 magnification. On the microphotographs taken at 1000 magnification, the numbers of opened and patent dentinal tubules per unit area(10,640${\mu}m^2$) were counted. And the diameters of opened dentinal tubules per unit are (10,640${\mu}m^2$) were measured. The differences of number and diameter among all groups were statistically analyzed by Kruskal Wallis Test. The results were as follows; 1. In the specimens applied with normal saline(control group), the root surface was finely cracked, and was covered by irregular smear layer. Neither exposed dentinal tubules nor any patent dentinal tubules could be seen. 2. In the specimens applied with saturated citric acid(experimental 1 group), the globular collagen fibers were exposed around the peritubular space, and many dentinal tubules were revealed. 3. In the specimens applied with tetracycline-HCl(experimental 2 group), the process-like collagen fibers were exposed around the peritubular space, and some dentinal tubules were revealed. 4. In the specimens applied with 15% EDTA(experimental 3 group), the root surface was covered by the collagenous fibrillar network, and many dentinal tubules were revealed. 5. The numbers of opened and patent dentinal tubules were significantly more in exp. 1 group and exp. 3 group than in exp. 2 group(P<0.05). But there was no significant difference between exp. 1 group and exp. 3 group. In control group, the number of opened and patent dentinal tubules could not be counted because any dentinal tubules couldn't be seen. 6 . The diameter of opened dentinal tubules was significantly smaller in exp. 1 group and exp. 3 group than in exp. 2 group(P<0.05). But there was no significant difference between exp. 1 group and exp. 3 group. In control group, the diameter of opened dentinal tubules could not be measured because any dentinal tubules couldn't be seen. The results demonstrate that root conditioning with citric acid, tetracycline- HCl, and EDTA is more effective in periodontal healing than only root planing, and 15% EDTA solution can replace low pH etching agents such as citric acid, tetracycline-HCl for root conditioning.

• Journal of Preventive Medicine and Public Health
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• v.32 no.3
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• pp.361-373
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• 1999

Objectives: Receive Operating Characteristic(ROC) curve with the area under the ROC curve(AUC) is one of the most popular indicator to evaluate the criterion validity of the measurement tool. This study was conducted to develop a standardized questionnaire to discriminate workers at high-risk of work-related musculoskeletal disorders using ROC analysis. Methods: The diagnostic results determined by rehabilitation medicine specialists in 370 persons(89 shipyard CAD workers, 113 telephone directory assistant operators, 79 women with occupation, and 89 housewives) were compared with participant's own replies to 'the questionnair on the worker's subjective physical symptoms'(Kwon, 1996). The AUC's from four models with different methods in item selection and weighting were compared with each other. These 4 models were applied to 225 persons, working in an assembly line of motor vehicle, for the purpose of AUC reliability test. Results: In a weighted model with 11 items, the AUC was 0.8155 in the primary study population, and 0.8026 in the secondary study population(p=0.3780). It was superior in the aspects of discriminability, reliability and convenience. A new questionnaire of musculoskeletal disorder could be constructed by this model. Conclusion: A more valid questionnaire with a small number of items and the quantitative weight scores useful for the relative comparisons are the main results of this study. While the absolute reference value applicable to the wide range of populations was not estimated, the basic intent of this study, developing a surveillance fool through quantitative validation of the measures, would serve for the systematic disease prevention activities.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.3
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• pp.520-527
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• 1999

For the purpose of providing some suggestions in selection of filling materials used in 'sandwich technique', the bond strengths between glass ionomer cement bases and composite resins were investigated and compared. For lining materials, 'Vitrebond' and 'Ketac-fil' were used. Using these two as bases, 10 of each following resins were built up on the top ; Z-100 (light curing resin) Clear-fil (chemical curing resin), Bis-core (dual cure resin), Dyract (compomer), therfore 10 specimens of each group and total of 80 specimens were made. After storing specimens in $37^{\circ}C$ deionized water for 24 hours, the shear bond strengths were measured under universal testing machine with 50 kg of full load scale and 1mm/min of cross-head speed and obtained the results as follows : 1. Over Vitrebond base, Z-100 showed the lowest bond strength but the other three did not show any difference in bond strength. 2. Over Ketac-fil base, Clear-fil showed the highest bond strength followed by Dyract, Bis-core, and Z-100 showed the lowest bond strengths. 3. Whereas Clear-fil showed the similar bond strengths on the Vitrebond base as other resins, it showed the highest bond strength on Ketac-fil base, which showed some difference in bond strength by differing GIC bases. 4. The bond strengths between base materials and composite resin showed a stronger resin-dependence tendency in cases with Ketac-fil bases rather than with Vitrebond bases.

• Journal of Korean Orthopaedic Sports Medicine
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• v.5 no.1
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• pp.41-44
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• 2006

Purpose: To evaluate the short-term results of arthroscopic ACL reconstruction using fresh frozen Achilles allograft Materials & Methods: From March 2002 to March 2004, arthroscopic ACL reconstructions using fresh frozen Achilles allograft were performed in 25 knees of 25 patients. The average age at operation was 30.1 years (range, 18-50 years) and the average follow-up was 17 months (range, 12 to 27months). Preoperative and follow-up clinical results were evaluated using the Lysholm knee score, IKDC knee rating system, physical examination and KT-2000 arthrometer. Results: The Lachman test was positive in 25 patients preoperatively and 18 patients(72%) had negative results at latest follow-up. The average side-to-side differences of anterior tibial translation using KT-2000 arthrometer under loading of 301b were improved from $7.9{\pm}2.4mm\;to\;2.6{\pm}1.6mm$. The average Lysholm score was improved from $61.1{\pm}13.9\;to\;93.5{\pm}5.3$ points. The IKDC grade was abnormal(C) or severely abnormal(D) in 25 cases preoperatively They improved 22(88%) of normal(A) or nearly normal(B) and 3(12%) of abnormal. Conclusion: Short term results of ACL reconstruction using Achilles allograft was acceptable. Achilles allograft can be a reasonable graft alternative to autograft for ACL reconstruction.

• Journal of Food Hygiene and Safety
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• v.21 no.2
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• pp.118-128
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• 2006

This study was conducted to determination of the endocrine distruptor function of 'Parabens' by dosing ethyl paraben, propyl paraben, isopropyl paraben, butyl paraben and isobutyl paraben to the immature SD rats. 18 groups were given vehicle control group, negative control group (Dibutyl phthalate), postive control group ($1'7-{\alpha}$ Ethynylestrdiol) and each paraben groups involved 3 dose level. Rats were injected with 62.5, 250 and 1,000mg/kg from postnatal day 19 till 21 once a day in subcutaneous and a total 3, times. There was no treatment related death. but, subcutaneous nodule, edema, alopecia and scrub formation on injection site was observed. These signs was become worse in high dose level. these signs was cause from physical stimulation by test substance which parabens were mix with com oil as vehicle. In the analysis of organ weights, absolute and relative weights of brain, spleen, liver, thymus, heart, kidneys, adrenals, ovaries and vagina were no difference with control group. but, wet and blotted weight of uterus was increased in every high dose parabens treat group. Especially, all dose level of isobutyl paraben was showed increment of uterus weight. uterus dilatation of parabens treated group was observed in gross anatomic pathology and these result was agree with wet and blotted weight of uterus. In the result of this study, estrogenic effect as endocrine distruptor was observed in ethyl paraben, propyl paraben, isopropyl paraben, butyl paraben and isobutyl paraben. and it was considered isobutyl paraben has highest estrogrnic effect under the condition of this study.

• Food Science and Preservation
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• v.9 no.3
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• pp.271-276
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• 2002

To develop a wrapping film, which suppresses the microbial decay through the storage and prolongs the selflife of fruits and vegetables, the antimicrobial packaging films were prepared and applied to the preservation of strtwberries and cucumbers. Low density polyethylene(LDPE) film of 50㎛ thickness was faricated with 1% of Scutellariae baicalensis extract. The LDPE film impregnated with Scutellariae baicalensis extract showed antimicrobial activity on the disk test against Bacillus cereus, Escherchia coli and Fusarium sp.. The antimicrobial film changed the color and light transmittance, but did not affect heat shrinkage, mechanical tensile strength and wattability. Strawberries and cucumbers were separately wrapped with packaging films in the state of closely-adhered packaging as well as modified atmosphere packaging(MAP). The wrapped strawberries and cucumbers were stored for 21 days at 5$\^{C}$ and for 40 days at l0$\^{C}$, respectively. For the packaged strawberries and cucumbers at 5$\^{C}$ and 10$\^{C}$, the LDPE film impregnated with Scutellariae baicalensis extract showed the reduced growth of total aerobic bacteria, molds and yeasts and did not give any negative effect on other quality attributes during storage in comparison with conttrol film without any additive.

• Journal of Radiation Protection and Research
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• v.37 no.4
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• pp.208-212
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• 2012

In previous studies, ovarian follicle in rat has been used a higher radiation dose than that for cancer radiotherapy in clinical practice. The aim of this study was to evaluate the effect of radiation dose used for cancer radiotherapy on ovarian follicle atresia in rat. Mice of 4-week-old female were whole body irradiated with 2 cGy or 2 Gy (Mevatron 67, Siemens, Germany) and sacrificed by cervical dislocation. Ovaries were collected at 24 hours after irradiation to observe the degree of follicular atresia. Ovaries were fixed in neutral formaldehyde solution for 24 hours and embedded with paraffin. Cutted in $5{\mu}m$ thickness with microtome and stained with hematoxylin and eosin (H&E) and TUNEL immunohistochemical stain, and examined histologically under a light microscope. All data were presented as mean ${\pm}SD$, calculating the ratio of normal or atretic follicles to total ovarian follicles. Statistical analysis was performed by the Mann Whitney test using the SPSS ver 19.0. Ratio of atretic to total follicles of 2 Gy group was significantly higher than control or 2 cGy groups (p<0.05). Ratio of normal to total follicles of 2 Gy group was significantly lower than control group in preantral follicle (64.0 vs. 87.7, p=0.027). Ratio of normal to total follicles of 2 cGy group was significantly increased more than control or 2 Gy groups in antral follicle, and there were no significant difference between control and 2 Gy groups (p=0.522). Radiation dose of 2 Gy for cancer radiotherapy have a significant effect on ovarian follicle atresia in rat.

• The Korean Journal of Elementary Counseling
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• v.6 no.1
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• pp.141-169
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• 2007

One of the most common feelings in everyday life is anger. Anger plays an important role in activating emotional energy and increasing intolerance when confronted with hardships, frustration and improper treatments. And it provides us with controlling interpersonal behavior, organizing internal, physiological, psychological process and various adaptive functions. If anger is not properly expressed, it brings about offensive attitude, leading to not only physical impairment but also anxiety in interpersonal relations and maladaptive to everyday life. For elementary school students, frequent quarrels, abusive words and defiant attitude toward adults are also caused by students' anger. Therefore, students' anger is one of the most difficult problems to be dealt with not only psychologically but also in elementary schools. In this respect, after investigating frequently experienced anger- inducing situations and inventing anger-inducing situation questionnaire, we postulated specific situations changing irrational belief into rational one. Based on these situations, we accounted for how to cope with anger inducing factors and change irrational belief into rational one, introducing several strategies needed to control anger, invented cognitive behavioral anger control program and tried to clarify the relationship between anger inducing experience and anger regulation ability. In order to derive usual anger-inducing situations, we made 180 students with fifth and sixth grade to record the reason why he/she got angry, mood, thought, behavior and result. Through this process, we could derive 47 situations bringing about anger and prepared anger-inducing situation questionnaire. It can be divided into 3 anger inducing situations by using factor analysis into 500 elementary students of fifth and sixth grade. Cognitive behavioral anger control program used in this study consists of 13 sessions. From first to fifth session, it is composed of 10 anger control methods to make students be aware of and control their anger. From sixth through thirteenth session, the relationship between irrational belief and anger inducing is introduced is focused on how irrational belief is changed into rational one. To examine the effects of the program, high anger students and the students lacking anger control are selected. Thirty students through pre-test using anger-inducing questionnaire and anger control ability questionnaire are taught the goals and procedures. Volunteer students and students with parents' consent allocated to experimental group (12 students) and the rest of the students are control group (12 students). Cognitive Behavioral Anger Control Program are applied every 50 minutes twice a week for 7 weeks and 4 weeks before and after this program, anger-inducing situation questionnaire and anger control ability questionnaire are practiced. Data collected in this study analyzed by SPSS and Kwakstat. In the middle of this program, quarterly reports and satisfaction measuratings were evaluated to examine whether there is verbal and non-verbal behavior change and students feel satisfied with the program. The results of this study are as follows: First, Cognitive-behavioral anger control program used in this study effectively reduced anger experience and lasted for 4 weeks. Second, cognitive behavioral anger control program increased students' ability to control anger inducing situations and also effective for 4 weeks. And its effect on verbal and non-verbal behaviour was very impressive Students come to realize that irrational belief is the cause of their anger and actively apply cognitive-behavioral anger control technique to themselves as well. Students became improved in their peer relations and felt confident in everyday life. The overall evaluation of this program can be listed as follows; "very satisfactory (91.67%)", "satisfactory (8.33%)", "very helpful (91.67%)", "helpful (8.33%). In this study we first investigated several anger-inducing situations and invented anger-inducing situation questionnaire and then applied cognitive behavioral anger control program in order to control their. anger and not to experience it. By creating workbooks and manuals this method can easily be used in school education settings.

• Journal of Korean Society of Forest Science
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• v.81 no.3
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• pp.224-233
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• 1992

This report succeds the previous paper, the source of materials and statistical designs used were not altered. Under the hypothesis of maleffect of atmospheric pollutions emitted mainly by traffic automobiles on 20-year-old, Prunus yedoensis roadside trees planted along national road between Cheonju abd Kunsan, chlorophyll a and b contents, magnesium and sodium contents of leaves were analysed on September 15. Besides control sites considered to be a pollution free district, 20 polluted road-side sites, 10 on left roadside and 10 on right roadside, oppositely faced in pairs were selected. The leaves collected from 5 trees at each sampling site were bulked to eliminate the individual tree variation. Chlorophyll were extracted by Mackinney and Arnon method. The results obtained are as follows : 1. The planting belt width between road shoulder and paved road face edge for cherry trees, 160~170cm, was considered too narrow for the growing space. 2. On an average, the total chlorophyll content between Cheonju and Iri($8.60{\sim}9.31ml/cm^2$) was lower than that for between Iri and Kunsan($9.24{\sim}10.74ml/cm^2$). 3. The chlorophyll b content showed the difference, higher on right roadside and lower on left side. However this difference could be confirmed by matched pair T-test at 10% level. 4. Without exception, the chlorophyll contents of control sites were higher than those of road-side trees, implying the maleffect of atmospheric pollutants on cherry tree growth. 5. On the contrary, magnesium and sodium contents of the leaves of road-side trees were higher than that of control site trees.

• The Korean Journal of Nuclear Medicine
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• v.35 no.5
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• pp.334-341
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• 2001

Purpose: Ascorbic acid us known to act as an antioxidant. Therefore, it can be used in increasing the efficiency of radiochemical labeling of Technetium-99m setamibi by inhibition of oxidation of $Sn^{2+}$ at low concentration. We intended to estimate the efficiency of radiochemical labeling and the stability of the newly formed formulation when ascorbic acid was added to a commercial kit. Materials and Methods: Synthesis of sestamibi was performed according to Dong-A's patent procedure (No.10-2001-0012877). First, we undertook a study to evaluate the efficiency of radiochemical labeling of sestamibi containing ascorbic acid. The stability of the vials was assessed using either $7.5{\mu}g\;or\;75{\mu}g$ of ascorbic acid, added to commercial vials under the accelerated condition(Temp : $40^{\circ}C{\pm}2^{\circ}C$, Relative humidity : $75{\pm}5%$). Results: Sestamibi was synthesized in overall 35-40% yield over 5 steps from a commercially available methallyl chloride as a starling material. When ascorbic acid was added, the efficiency of radiochemical labeling was maintained compared to the vial with no ascorbic acid. The accelerated test showed that the addition of ascorbic acid inhibited the oxidation of $Sn^{2+}$ ion by antioxidation mechanism. Also, the efficiency of radiochemical labeling of this vial after 9 months was nearly the same as the starting point. Therefore, the storage period of the kit is likely to be extended. Taken together, it suggests that the addition of ascorbic acid as a stabilizer is desirable. Conclusion: To increase the stability of a sestamibi cold kit, it is desirable to add ascorbic acid as a stabilizer to the commercial formulation.