• Korean Journal of Environmental Agriculture
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• 제20권3호
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• pp.155-161
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• 2001

This study was carried out to investigate cytotoxicity of paraquat or bentazone on NIH 3T3 fibroblasts, toxicity of paraquat or bentazone, and compensatory effects of 3-Methylcholanthrene(3-MC) on the rat liver. In order to MTT assay, the $5.0{\times}10^4$ cell/mL of NIH 3T3 fibroblast in each well of 24 multidish were cultured. After 24 hours, the cells were treated with solution of paraquat or bentazone(1, 25, 50, 100 ${\mu}M$ respectively). After the NIH 3T3 fibroblast of all groups were cultured in same condition for 48 hours. MTT assay were performed to evaluate the cytotoxicity of cell organelles. Paraquat or bentazone $MTT_{50}$ were 1668.97 ${\mu}M$ and 1506.97 ${\mu}M$, respectively. These $IC_{50}$ of paraquat or bentazone were decided low cytotoxicity by Borenfreund. In order to observe the toxicity and compensatory effects of paraquat or bentazone on the rat liver, Sprague-Dawley male rats were used as experimental animals and divided into paraquat or bentazone only treated group and simultaneous application group of paraquat or bentazone and 3-MC. At 30 min and 1, 3, 6, 12, 24, 48 and 96 hrs interval after each treatment, the animals were sacrificed by decapitation and liver were immediately removed, immersed in fixatives, and processed with routine method for light microscopic study. Paraffin sections were stained with H-E, PAM and Best Carmine. Under the light microscope, degenerative changes of hepatic lobules were frequently observed in portal area from 3 hrs after paraquat or bentazone treatment. All hepatic cells were induced degenerative change at 12 hrs and more severe degenerative change at 48 hrs after paraquat or bentazone treatment. Especially, hepatic cells of bentazone only treated group were distinctly showed pyknotic. Glycogen granules were increased in portal area at 3 hrs, all hepatic cells at 12 hrs and remarkably increased at 48 hrs after paraquat or bentazone treated group. But hepatic cells of bentazone only treated group were regeneration at 48 hrs from portal area and glycogen granules of hepatic cells of paraquat or bentazone and 3-MC combination treated group showed in central area only at 48 hrs. The results indicate that 3-MC may be decrease paraquat or bentazone cytotoxicity on the rat liver.

• The Journal of Korean Academy of Prosthodontics
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• 제47권3호
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• pp.301-311
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• 2009

Statement of problem: Flapless implant surgery using a soft tissue punch device requires a circumferential excision of the mucosa at the implant site. To date, Although there have been several reports on clinical outcomes of flapless implant surgeries, there are no published reports that address the appropriate size of the soft tissue punch for peri-implant tissue healing. Purpose: In an attempt to help produce guidelines for the use of soft tissue punches, this animal study was undertaken to examine the effect of soft tissue punch size on the healing of peri-implant tissue in a canine mandible model. Material and methods: Bilateral, edentulated, flat alveolar ridges were created in the mandibles of six mongrel dogs. After a three month healing period, three fixtures (diameter, 4.0 mm) were placed on each side of the mandible using 3 mm, 4 mm, or 5 mm soft tissue punches. During subsequent healing periods, the peri-implant mucosa was evaluated using clinical, radiological, and histometric parameters, which included Gingival Index, bleeding on probing, probing pocket depth, marginal bone loss, and vertical dimension measurements of the peri-implant tissues. Results: The results showed significant differences (P <0.05) between the 3 mm, 4 mm and 5 mm tissue punch groups for the length of the junctional epithelium, probing depth, and marginal bone loss during healing periods after implant placement. When the mucosa was punched with a 3 mm tissue punch, the length of the junctional epithelium was shorter, the probing depth was shallower, and less crestal bone loss occurred than when using a tissue punch with a diameter $\geq$ 4 mm. Conclusion: Within the limit of this study, the size of the soft tissue punch plays an important role in achieving optimal healing. Our findings support the use of tissue punch that 1 mm smaller than implant itself to obtain better peri-implant tissue healing around flapless implants.

• Journal of the korean academy of Pediatric Dentistry
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• 제31권2호
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• pp.190-201
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• 2004

The aim of this study was to evaluate the resistance to degradation and to compare the wear resistance characteristics of four esthetic restorative materials in an alkaline solution. The brands studied were Charmfil, Charmfil flow(composite resin), Compoglass F and PrimaFlow(compomer). The results were as follows: 1. The mass loss were not significantly different among the materials(p>0.05). 2. The sequence of the degree of degradation layer depth was in descending order by Compoglass F, PrimaFlow, Charmfil, and Charmfil flow. There were significant differences between Compoglass F and the others(p<0.05). 3. The sequence of the Si loss was in descending order by Charmfil flow, Charmfil, PrimaFlow, and Compoglass F. There were significant differences among these materials(p<0.05). 4. When observed with SEM, destruction of bonding between matrix and filler was observed and when observed with CLSM, the depth of degradation layer of specimen surface was observed. 5. The sequence of maximum wear depth was in descending order by Comfoglass, PrimaFlow Charmal, and Charmfil flow. There were significant differences among these materials(p<0.05). 6. The correlation coefficient between Si loss and degradation layer depth (r=0.602, p<0.05) Vicker's hardness number and maximum wear depth (r=0.501, p<0.05) were relatively high. These results indicate that wear and hydrolytic degradation may be considered to be evaluation factors of composite resins and compomers.

• The Korean Journal of Rehabilitation Nursing
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• 제3권1호
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• pp.27-42
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• 2000

The purpose of this study was to identify the degree of sexual adjustment and quality of life in married men with spinal cord injuries and to furnish primary data to sexuality rehabilitation nursing practice which can lead to ideal sexual life and quality of life those men with SCI. Seventy married men with SCI were conveniently sampled in Kwangju, Suncheon, Mokpo and Seoul for responding the questionnaire, which was based on this research. With the research scale, SIS (Sexual interest and satisfaction) by Siosteen et al.(1990) and SB(Sexual behaviour) by Kreuter et al.(1996) were used for the measurement of sexual adjustment. And, for measuring quality of life was used SCI QL-23(Spinal cord injury of life-23) scale by Lundqvist et al.(1997). Data were collected from January 20 to March 20, 1999, using a structured questionnaire. A hundred volumes of questionnaire were used. and 85 volumes were collected, 70 volumes were used as research data after excluding 15 volumes unsuitable to data analysis. The obtain data were analysed using percentage, t-test, ANOVA, Duncan test, and Pearson's correlation by SAS PC+ program. The results were as follows: 1. The mean score of sexual interest and satisfaction of the subjects was 8.42. out of 18. The ways of their sexual behavior after spinal cord injuries were embracing and caressing (62.9%), kissing(58.6%), caressing breast with hands (55.7%), caressing breast with hands (52.9%), caressing genitals with hands (37.2%), caressing genitals with mouth(30.0%) and sexual intercourse (18.6%). The mean score of quality of life was 52.53 out of 100. 2. Age(F=3.24, p=.045) and caregiver (F=4.02, p=.022)were major variables which reveals significant differences in terms for sexual interest and satisfaction. The later results on Duncan's test showed that subjects who were in their 30s or 40s were significant higher than subjects whose age were in their 50s in their sexual interest and satisfaction. Also subjects with their spouse's care or mother's care were higher than those with other's care. 3. Subjects with incomplete paraplegia were higher than those with the complete paraplegia in sexual interest and satisfaction (F=3.01, p=.036). 4. Variables that showed the significant differences in the quality of life were education(t=2.860, p=.007) and period of marriage(t=2.125, p=.037). and occupational status(t=-2.161, p=.034). High school graduates, those who married before spinal cord injuries and those who didn't have occupation were higher than the other subjects. 5. Variables that revealed significant differences in the quality of life were time passage after spinal cord injuries(F=8.72, p=.001) and injured level of spinal cord(F=3.32, p=.042). Duncan's test showed that subjects who had lived for less than 4 years were higher those with time passage of 5-9 years and 10 years. Also subjects with lumbar injuries were higher than those with thoracic injuries in terms of quality of life. 6. There was negatively correlated between sexual interest and satisfaction and quality of life(r=-.256, p<.05). As a result of these findings sexuality rehabilitation for individuals with SCI was very important issue for their quality of life. Thus, registered nurses who care clients with SCI should activily participate in the client's sexual needs. Also, various sexual behaviors as well as sexual intercourse should be encouraged for the sexual adjustment of client's with SCI.

• Tuberculosis and Respiratory Diseases
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• 제46권6호
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• pp.846-855
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• 1999

Background : Secondary pulmonary hypertension is an important final endpoint in patients with chronic hypoxic lung disease, accompanied by deterioration of pulmonary hemodynamics. The clinical diagnosis of pulmonary hypertension and/or cor pulmonale could be difficult, and simple noninvasive evaluation of pulmonary artery pressures has been an relevant clinical challenge for many years. Doppler echocardiography might to be a more reliable method for evaluating pulmonary hemodynamics in such patients in terms of the accuracy, reproducibility and easiness for obtaining an appropriate echocardiographic window than M-mode echocardiography. The aim of this study was to assess echocardiographic parameters associated with pulmonary arterial hypertension, defined by increasing right ventricular systolic pressure(RVSP), calculated from trans-tricuspid gradient in patients with chronic hypoxic lungs. Method : We examined 19 patients with chronic hypoxic lung disease, suspected pulmonary hypertension under the clinical guidelines by two dimensional echocardiography via the left parasternal and subcostal approach in a supine position. Doppler echocardiography measured RVSP from tricuspid regurgitant velocity in continuous wave with 2.5MHz transducer and acceleration time(AT) on right ventricular outflow tract in pulsed wave for the estimation of pulmonary arterial pressure. Results : On echocardiography, moderate to severe degree of pulmonary arterial hypertension was defined as RVSP more than 40mmHg, presenting tricuspid regurgitation. Increased right ventricular endsystolic diameter and shortened AT were noted in the increased RVSP group. Increased RVSP was correlated negatively with the shortening of AT. Other clinical data, including pulmonary functional parameters, arterial blood gas analysis and M mode echocardiographic parameters were not changed significantly with the increased RVSP. Conclusion : These findings suggest that shortened AT on pulsed doppler can be useful when quantifying pulmonary arterial pressure with increased RVSP in patients with chronic lung disease with hypoxemia. Doppler echocardiography in pulmonary hypertension of chronic hypoxic lungs is an useful option, based on noninvasiveness under routine clinical practice.

• Applied Biological Chemistry
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• 제19권4호
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• pp.202-218
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• 1976

In this experiment American Summer Pairman apple was selected as test fruit in order to study the effect of sub-atmospheric pressure storage in the apple. keeping a certain pressure condition, a new sub-atmospheric pressure system was designed and constructed in which fruits were stored at $25^{\circ}C$ under two different atmospheric pressure conditions such as Normal Atmospheric Pressure (NAP) and Sub-Atmospheric Pressure (SAP). Moreover, they were divided into plots of 5% and 0% of $CO_2$, on the basis of gas composition. Under these conditions, the amount of respiration and ethylene evolution, and the changes of intercellular gas composition and organic components were investigated throughout the storage. The results obtained are as follows: (1) The intercellular gas was exhausted so rapidly by the SAP treatment that the gas equilibrium in the tissues reached within 5 minutes. (2) The amount of respiration was found to be higher in plots of NAP than SAP, and under the conditions, controlling $CO_2$ content, plots of $CO_2$ 5% were lower in the amount of respiration than $CO_2$ 0%. The climateric rise was revealed more slowly in plots of the SAP than NAP. These results indicate that the SAP treatment was an efficient method for controlling the respiration of fruits. Furthermore, these results were also realized with the results of the respiratory quotient (R.Q) and intercellular gas composition. (3) Evolution of ethylene, the ripening hormone in plant, was shown the similar tendency to the climacteric pattern of respiration; at the stage of climacteric maximum, the maximun amount of ethylene was found earlier in plots of NAP than SAP, and post climacteric stage was prolonged in the plots of the SAP compared to those of the NAP. The ethylene concentration in tissue appeared lower in plots of the SAP than NAP, which might suggest that the SAP treatment was caused to restriction of ethylene evolution. (4) Effects of the SAP treatment mentioned hitherto were proved also with the test of the external appearance such as changes of color and freshness, firmness, rotting and weight loss. (5) In the investigation of organic components, vitamin C and organic acids varied less in plots of SAP than NAP. Specially, it was remarkable that the loss of malic acid was least decreased by the SAP treatment. These effects of the SAP treatment were distinctive in the changes of the ratios of malic and citric acid to total acid, and the ratios of free sugar to free acid.

• Journal of Korean Society of Industrial and Systems Engineering
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• 제35권4호
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• pp.227-234
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• 2012

In this study, the masking effect of olfactory stimulus on the awakening state due to sound stimuli while driving using Graphic Driving Simulator was observed through the response of autonomic nervous system. The test was conducted for 11 males in their twenties. The siren of ambulance car was presented to them as auditory stimulus for 30 secs while driving in a situation of high way in the condition of both peppermint and control, respectively, and LF/HF ratio of HRV (Heart Rate Variability), the activity index of sympathetic nerve, and GSR (Galvanic Skin Response) response were examined. The test was proceeded in the order of three stages, that is, sound stimuli (test 1), driving performance, and sound stimuli (test 2), and fragrance stimulus, driving performance, and sound stimuli (test 3), and the physiological signal of GSR, HRV was measured in the whole stages. As a result of test, comparing the results of before and after auditory stimulus test (1) (p < 0.01), test (2) (p < 0.05), and test (3) (p < 0.01), driving performance test (2) (p < 0.01), test (3) (p < 0.01), and olfactory stimulus test (3) (p < 0.05), respectively, GSR response increased, showing significant difference in all the tests. It indicates that when auditory stimulus was presented to the subjects, they were in the awakening state as sympathetic nervous system got activated. As a result of comparing auditory stimulus while driving before and after presenting olfactory stimulus, there was no significant difference in GSR response. The LF/HF ratio of HRV increased, showing a significant difference only in test (2) (p < 0.05), and in driving performance test (2) (p < 0.05) in auditory stimulus, however, it showed no significant difference in olfactory stimulus. As a result of comparing auditory stimulus while driving before and after presenting olfactory stimulus, there was a decrease, showing significant difference (p < 0.05) in LF/HF ratio of HRV. That is, it means that the activation of sympathetic nervous system decreased, and that parasympathetic nervous system got activated. From these results, it was observed that while driving, the awakening level due to auditory stimulus was settled with olfactory stimulus. In conclusion, it was drawn that while driving, olfactory stimulus could have the masking effect on auditory stimulus.

• Journal of the Society of Cosmetic Scientists of Korea
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• 제32권2호
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• pp.105-110
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• 2006

This study was to describe the differences in efficacy and effect of herbal extracts by the part and solvent extraction from the medical plants used as materials of oriental herbs cosmetics. And, this study was to apply to the test method of efficacy and effect related to the antioxidation as herbal extracts, complex of actual ingredient, not existing analytical methods of single ingredient. After screening the medical plants with the antioxidative activity primarily and selecting 11 sorts of medical plants to be used by the part in the literature, this study was to confirm the differences through the well-known test methods like DPPH radical scavenging activity test and hydroxyl radical scavenging activity test. For examples, in case of Trachelospermum asiaticum, compared with the aerial part and fruit, the value of DPPH radical scavenging activity test had $25.2 {\pm} 0.2$ and $62.4 {\pm}1.6$ each. It has shown that the value of fruit had 2.4 times higher effect than the one of aerial part. In case of hydroxyl scavenging activity test, it was effective in the fruit, but it has shown that there was no effect on the aerial part. It showed the same phenomena in some other plants. From the result above, this researcher could understand that it needed to consider extracting the medical plants or plants with the active principle by the part. Also, this study was to confirm the differences in effect according to the solvent as it changed the solvent extraction after selecting a plant (Lithospermum erythrorhizon) widely used for medicine and dye. As a result of measuring the actual value of superoxide scavenging activity test, this study was to consider that there were differences by the part or solvent extraction in extracting and using the medical plants as it has shown that the effect differences produced $10{\sim}80%$ according to the solvent. When it was applied to the products, this study has shown that it needed to decrease the possible errors.

• Journal of the Korean Chemical Society
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• 제52권1호
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• pp.96-106
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• 2008

The purpose of this study was to identify the actual conditions of operation in school and investigate the perceptions of science teachers and students regarding the 7th elective-centered curriculum of high school science subjects. For this study, a questionnaire survey was conducted for the selected subjects including 127 high school science teachers and 763 high school students in their third year who had experienced the 7th elective-centered curriculum. As a result of the study, concerning the way to present the elective subjects of science, many cases were the alternative way and the group-elective way in humanity courses while natural science courses had the alternative way and the free-elective way in most cases. In other words, in many cases, the right of elective was given within a limited range. The result of the investigation on science teachers' perceptions on the elective-centered curriculum was that negative views dominated as a whole. Especially, earth science teachers showed the most negative attitudes. The number of biology and chemistry teachers who supported students' right to opt subjects were lower than that of physics teachers and earth science teachers who were against it. To help students make a right choice, many viewed that the system of the college Scholastic Ability Test should be complemented in order to prevent any disadvantage to each elective subject or that it was necessary to have systematic and realistic career education. As the result of investigating the perception of high school students in their third year regarding the elective-centered curriculum, they were usually not very satisfied with it. As the reason for it, many said the selection right was limited. Many others also expressed that there were lack of public relations and education on subjects and careers. Based on these results, limits still exist in accepting all demands although there are a lot of efforts made to smoothly adjust supply and demand of science teachers as well as students' electives in the field of school. It is considered necessary to come up with counterplan and complements to prevent basic science from being neglected or lower academic achievement in the subject of science from happening, and at the same time to harmoniously deal with supply and demand of science teachers as well as the issues of students' demands given the actual conditions of school.

• Korean Journal of Agricultural Science
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• 제3권1호
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• pp.121-134
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• 1976

There are many evidences that vaiious plant pathogenes were introduced with imported plants and agricultural productsrfrom foreign countries and caused heavy losses of domestic economic plants, ever since the early twentieth century when our country began to trade plants and agricultural products with foreign countries. There are many ways that foreign plant pathogenes have been introduced into our country, but the main route is considered to be imported plants and agricultural products contaminated with plant pathogenes. Plant quarantine which prevent effectively introduction of plant pathogenes from abroad was practiced for the first time in our country in 1912, and that is relatively earlier activity in the history of plant quarantine of the world. Several plant pathogenes have been introduced into our country even after plant quarantine had been practiced. Particularly for about 15 years, from the 2nd World War to 1961 when the law of Plant Protection was enacted and practical works of plant quarantine was reoperated, Korean agriculture was opened to various foreign plant pathogenes as a lapse period of plant quarantine in our country. Introduced plant pathogenes are, for the most part, from Japan because of depending upon Japan in the foreign trade of plants and agricultural products of our country. As present plant quarantine is required more exactness and rapidness, reasonable organization of quarantine system including more trained quarantine specialists, modernized facilities and introduction of improved quarantine techniques are necessary. Reasonable organization and improvement of plant quarantine system are important not only for protection of korean agriculture to plant pathogenes possible to be introduced from foreing countries, but also for increasing and stabilization of export of plants and agricultural product of our country.