• Title/Summary/Keyword: knowledge levels

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The Effects of Science Question Enhancement Instruction on the Science Question Level and Achievement of Middle School Students (질문 강화 수업이 중학생들의 질문 수준과 학업 성취도에 미치는 영향)

  • Chung, Young-Lan;Bae, Jae-Hee
    • Journal of The Korean Association For Science Education
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    • v.22 no.4
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    • pp.872-881
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    • 2002
  • Student questioning is included in the priority of science literacy, to enable students to solve problems by exploring questions, communicating and constructing knowledge(AAAS, 1989). Also, the essence of student questioning in science lies in its function as a link between thinking and learning. But educators did not pay much attention to students' questioning in Korea. The purpose of this study was to investigate the effects of science question enhancement instruction on students' science questioning level and achievement. Also, this study showed the effects of other variables(logical thinking, science achievement, interest, and gender) on students' science questioning level. The pretest-posttest control group design group design was used. The sample was consisted of 80 second grade middle school students in experimental group(Science question enhancement instruction) and 74 students in control group(Traditional learning). Students in both groups were received identical content instruction on the unit 'Structures and functions of plant'. These groups were treated for 15 hours during 6 weeks. Students' questions were rated using the four levels described by the Middle School Students' Science Question Rating Scale(r= .96,)(Cuccio-Schirripa & Steinner, 2000). Science achievement data were collected using a 17 item multiple choice test(Cronbach ${\alpha}$= .84). To investigate students' logical thinking ability, a abridged GALT(Cronbach ${\alpha}$= .69) was used. Five-way ANOVA, ANCOVA, and multiple regression analysis were used to analyze the results. The results indicated that students who received instruction on researchable questioning outperformed those students who were not instructed on high-order questioning(p< .01). Results of correlations indicated that instruction(r= .640), science achievement(r= .311) and logical thinking ability(r= .212) was significantly and positively related with students' questioning level. But, interest and gender did not show any significant correlation with students' questioning level. Science question enhancement instruction was more effective on science achievement than the traditional instruction(p< .01).

A study of the effects of PDGF-BB on the characteristics of bone stromal and periodontal ligament cells (혈소판유래성장인자-BB가 골간질세포와 치주인대세포의 성상에 미치는 영향)

  • Kwon, Young-Hyuk;Park, Joon-Bong
    • Journal of Periodontal and Implant Science
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    • v.26 no.4
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    • pp.949-965
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    • 1996
  • The main goal of periodontal therapy is to restore the lost periodontal tissue and establish the attachment appratus. Current acceptable therapeutic techniques are included : removal of diseased soft tissue, demineralization of exposed root surface, using the barrier membrane for preventing the downgrowth of gingival epithelial cell, insertion of graft materials as a scaffolding action, and biological mediators for promoting the cell activity. The latest concept one among them has been studied which based on the knowledge of cellular biology of destructed tissue. Platelet-derived growth factor(PDGF) is one of the polypeptide growth factor which have been reported as a biological mediator to regulate activities of wound healing progress including cell proliferation, migration, and metabolism. The purposes of this study is to evaluate the influences of the PDGF as biological mediator to periodontal ligament and bone marrow cell. Both right and left maxillary first molar were extracted from rat which had treated with 0.4% ${\beta}-Aminopropionitril$ for 5 days, and feeded until designed date to sacrifice under anesthesisa. Periodontal ligament were removed from the extracted socket of the rat, and cultured with Dulbecco's Modified Essential Medium(DMEM) contained with 10% Fetal Bovine Serum, 100U/ml penicillin, $100{\mu}g/ml$ streptomycin, $0.5{\mu}g/ml$ amphotericin-B. Bone marrow cell were culture from bone marrow suspension with which washed out from femur with same medium. The study was performed to evaluate the effect of PDGF to periodontal ligament and bone cell, cell proliferation rate, total protein synthesis, and alkaline phosphatase activity of rat periodontal ligament(PDL) cell and bone stromal(RBS) cell in vitro. The effects of growth factors on both cells were measured at 3, 5th day after cell culture with (control group) or without growth factors(experimental group). The results were as follows: 1. The tendency of cell proliferation under the influence of PDGF showed more rapid proliferation pattern than control at 3 and 5 days after inoculation. 2. The activity of Alkaline phosphatase revealed 14, 80% increased respectively at 3, 5 days culture than control group. Measurements of ALPase levels indicated that PDL cells had significantly higher activity when compared with that of co-culture groups and GF only(P<0.05). And, ALPase activity in 10 days was higher than that of 7 days(P<0.05). 3. The tendency of formation of the mineralized nodule were observed dose-depend pattern of PDL cells. There was statistically significant difference among group l(PDL 100%), 2(PDL 70%:GF 30%), and 3(PDL 50%:GF 50%)(P<0.01). But, there was no difference among group 3, 4(PDL 30%:GF 70%), and 5(GF 100%). 4. Also, the number of nodule was greater in co-culture of PDL 70% and GF 30% than in culture of PDL 70%(P<0.05). From the above results, it is assumed that the PDGF on PDL cells and RMB cell culture. GF stimulates the cell growth, which is not that of PDL cells but GF. And, the activity of ALPase depends on the ratio of PDL cells, and ALPase may relate to the initial phase of nodule formation. Also, it is thought that the calcified nodule formation principally depends on PDL cells, is inhibited by GF, and affected by cell density. In conclusion, platelet-derived growth factor can promote rapid osteogenesis during early stage of periodontal tissue regeneration.

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Elementary School Students' Amounts of Sugar, Sodium, and Fats Exposure through Intake of Processed Food (초등학생의 주요 가공식품으로부터 섭취하는 당, 나트륨, 지방류 등의 노출실태 조사 연구)

  • Kang, Moon-Hee;Yoon, Ki-Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.1
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    • pp.52-61
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    • 2009
  • The purpose of this study was to investigate the extent of excessive sugar, sodium, cholesterol, and saturated fat consumptions by elementary school students through processed food's intake. A survey study was conducted with 384 fourth and sixth grade students and their mothers from two schools in Seoul and Gyeonggi province. The data were analyzed for the frequency analysis, chi-square test and Pearson correlation using the SPSS/Windows (ver. 15.0). Results showed that students consumed high amounts of sugars through processed milk and carbonated beverages, and yogurt. Additionally, they had high sodium and saturated fat levels in their diet through Ramen. There was significant correlation (p<0.01) between mothers' purchasing and students' intake of processed food. Overall, both students and mothers had some knowledge on the impact of sodium on human health. About 50 percent of the respondents did not have accurate information about cholesterol, saturated fat, and trans fat. More than 50 percent of students and mothers had no nutritional education on the risk of excessive intake of sugar, sodium, cholesterol, saturated fat, and trans fat. Top twenty percent of the students had 39.7 g of sugar, 940.1 mg of sodium, 17.8 mg of cholesterol, and 11.2 g of saturated fat through processed foods per day on the average. These results suggest that execution of nutritional education about processed food is needed for high risk group of elementary school students and their mothers. Moreover, government must enact the regulation and policy for the food industry to reduce the risky nutrients from children's favorite processed food.

A Study on the Botanical Garden Visitors' Eco-consciousness and Motivation (식물원 이용객의 생태의식과 이용동기에 관한 연구)

  • Jeong, Jae-Man
    • Korean Journal of Environment and Ecology
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    • v.28 no.2
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    • pp.235-246
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    • 2014
  • The purpose of this study was to determine the correlation between botanical garden visitors' ecological consciousness and their needs, in order to provide some effective measures to manage them. For this purpose, 3 study points were set up: "botanical garden visitors' ecological consciousness and their needs", "differences of such consciousness depending on their demographic variables" and the "relationship between such consciousness and their needs". To this end, Botanical garden visitors were surveyed for an empirical analysis. The visitors' awareness about ecology was measured with Dunlap's 15-item NEP Inventory, while their needs were analyzed in reference to Maslow's 7-Step Human Desire Ladder. The survey was conducted at Botanical garden for 3 days. As a result, a total of 360 questionnaires were returned. The results of this study can be summarized as follows; First, the visitors' ecological consciousness and their needs were higher than normal level. In terms of their consciousness of ecology, their awareness of the ecological crisis potential and anti-humanism were the highest. In terms of their needs, the aesthetic need was the highest, followed by the cognitive need. On the other hand, the needs for self-achievement and self-esteem were the lowest; except them, the higher the needs were positioned at Maslow's ladder of desire, the more responsive the subjects became. As a result of analyzing the correlation between the subjects' consciousness of ecology and their needs, it was found that the correlation was negative in some sub-areas, while being positive in other sub-areas. After all, the ratio of the sub-areas having a positive correlation was 3 times higher than that of the sub-areas having a negative correlation. Even as for the correlation coefficient values, they were higher in the positive sub-areas, which suggests that the correlation between wetland visitors' ecological consciousness and their needs was positive, although at a lower level, in overall terms. As a result of comparatively analyzing visitors' needs by dividing them into 3 sub-groups depending on the levels of their ecological consciousness, it was found that the higher their consciousness of ecology was, the higher their needs were. Overall, botanical garden visitors' ecological awareness was higher than the normal level, and it was estimated that such awareness would continue to increase. Hence, it could be inferred that their needs, particularly their aesthetic and cognitive ones, would also continue to increase. Accordingly, it is important to manage the wetland landscape making use of its visual resources, while keep providing the visitors with the contents fulfilling their need for knowledge.

A Study on Wetland Visitors' Awareness of Ecology and Their Needs (습지 방문객의 생태의식과 이용욕구 연구)

  • Jeong, Jae-Man;Oh, Jeong-Hak;Kim, Jin-Seon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.6
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    • pp.147-157
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    • 2013
  • The purpose of this study was to determine the correlation between wetland visitors' consciousness of ecology and their needs and thereby, provide for some effective measures to manage them. For this purpose, 3 study points were set up: "wetland visitors' consciousness of ecology and their needs", "differences of such consciousness depending on their demographic variables" and the "relationship between such consciousness and their needs". To this end, Upo Wetland visitors were surveyed for an empirical analysis. The visitors' awareness about ecology was measured with Dunlap's 15-item NEP Inventory, while their needs were analyzed in reference to Maslow's 7-Step Human Desire Ladder. The survey was conducted at Upo Wetland for 3 days, and as a result, a total of 228 questionnaires were returned. The results of this study can be summarized as follows; First, the visitors' consciousness of ecology and their needs were higher than the normal level. In terms of their consciousness of ecology, their awareness of the ecological crisis potential and anti-humanism was highest. In terms of their needs, the aesthetic need was highest, followed by the cognitive one. On the other hand, the needs for self-achievement and self-esteem were lowest; except them, the higher the needs were positioned at Maslow's ladder of desire, and subjects were more responsive to them. As a result of analyzing the correlation between the subjects' consciousness of ecology and their needs, it was found that the correlation was negative in some sub-areas, while being positive in other sub-areas. After all, the ratio of the sub-areas having a positive correlation was as 3 times high as that of the sub-areas having a negative correlation. Even as for the correlation coefficient values, they were higher in the positive sub-areas, which suggests that the correlation between wetland visitors' consciousness of ecology and their needs were positive, although at a lower level, in overall terms. As a result of comparatively analyzing visitors' needs by dividing them into 3 sub-groups depending on the levels of their consciousness of ecology, it was found that the higher their consciousness of ecology was, their needs were higher. Overall, wetland visitors' awareness of ecology was higher than the normal level, and it was estimated that such awareness would continue to increase. Hence, it could be inferred that their needs, particularly, their aesthetic and cognitive ones would continue to increase, too. Accordingly, it is deemed important to manage the wetland landscape making use of its visual resources, while continuing to provide the visitors with the contents fulfilling their need for knowledge.

The Changes of Dietary Reference Intakes for Koreans and Its Application to the New Text Book (한국인 영양섭취기준에 대한 이해 및 새 교과서에의 적용 방안)

  • Kim, Jung-Hyun;Lee, Min-June
    • Journal of Korean Home Economics Education Association
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    • v.20 no.2
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    • pp.75-94
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    • 2008
  • The purposes of this paper are to describe the newly established reference values of nutrient intakes: to apply the changed dietary reference intakes to the new text book based on the revised curriculum: and to contrive substantial contents in the domain of dietary life(foods & nutrition) of new text book. Dietary Reference Intakes for Koreans(KDRIs) is newly established reference values of nutrient intakes that are considered necessary to maintain the health of Koreans at the optimal state and to prevent chronic diseases and overnutrition. Unlike previously used Recommended Dietary Allowances for Koreas(KRDA), which presented a single reference value for intake of each nutrient, multiple values are set at levels for nutrients to reduce risk of chronic diseases and toxicity as well as prevention of nutrient deficiency. The new KDRIs include the Estimated Average Requirement(EAR), Recommended Intake(RI), Adequate Intake(AI), and Tolerable Upper Intake Level(UL). The EAR is the daily nutrient intake estimated to meet the requirement of the half of the apparently healthy individuals in a target group and thus is set at the median of the distribution of requirements. The RI is set at two standard deviations above the EAR. The AI is established for nutrients for which existing body of knowledge are inadequate to establish the EAR and RI. The UL is the highest level of daily nutrient intake which is not likely to cause adverse effects for the human health. Age and gender subgroups are established in consideration of physiological characteristics and developmental stages: infancy, toddler, childhood, adolescence, adulthood and old age. Pregnancy and lactation periods were considered separately and gender is divided after early childhood. Reference heights and weights are from the Korean Agency for Technology and Standards, Ministry of Commerce, Industry and Energy. The practical application of DRIs to the new books based on the revision in the 7th curriculum is to assess the dietary and nutrient intake as well as to plan a meal. It can be utilized to set an appropriate nutrient goal for the diet as usually eaten and to develop a plan that the individual will consume using a nutrient based food guidance system in the new books based on the revision in the 7th curriculum.

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Cross-Sectional Item Response Analysis of Geocognition Assessment for the Development of Plate Tectonics Learning Progressions: Rasch Model (판구조론의 학습발달과정 개발을 위한 지구적 인지과정 평가의 횡단적 문항 반응 분석: Rasch 모델)

  • Maeng, Seungho;Lee, Kiyoung
    • Journal of The Korean Association For Science Education
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    • v.35 no.1
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    • pp.37-52
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    • 2015
  • In this study, assessment items to examine geocognition on plate tectonics were developed and applied to middle and high school students and college students. Conceptual constructs on plate tectonics are Earth interior structure, specific geomorphology, and geologic phenomena at each plate boundary. Construct for geocognition included temporal reasoning, spatial reasoning, retrospective reasoning, and system thinking. Pictorial data in each item were all obtained from GeoMapApp. Students' responses to the items were analyzed and measured cross-sectionally by Rasch model, which distinguishes persons' ability levels based on their scores for all items and compared them with item difficulty. By Rasch model analysis, Wright maps for middle and high school students and college students were obtained and compared with each other. Differential Item Functioning analysis was also implemented to compare students' item responses across school grades. The results showed: 1) Geocognition on plate tectonics was an assessable construct for middle and high school students in current science curriculum, 2) The most distinguished geocognition factor was spatial reasoning based on cross sectional analysis across school grades, 3) Geocognition on plate tectonics could be developed towards more sophisticated level through scaffolding of relevant instruction and earth science content knowledge, and 4) Geocognition was not a general reasoning separated from a task content but a content-specific reasoning related to the content of an assessment item. We proposed several suggestions for learning progressions for plate tectonics and national curriculum development based on the results of the study.

Teaching Behavior, Confidence and Satisfaction among Teachers who Solo-Teach Technology and Home Economics in High School (고등학교 "기술.가정" 교과 교사의 교수행동, 교수자신감, 교수만족도)

  • Park Hyun-Jin;Shin Hye-Won
    • Journal of Korean Home Economics Education Association
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    • v.18 no.2 s.40
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    • pp.111-123
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    • 2006
  • This study was conducted on teachers who currently are teaching 'Technology and Home Economics' in high school, and teaching it alone, as opposed to team teaching. The study examined the teachers' fields of major study relative to their teaching behaviors and levels of confidence and satisfaction while teaching this course. The study also compared teaching behaviors, confidence and satisfaction among teachers who either have or have not participated in training sessions specifically-targeting teachers who are lack of relevant knowledge and skills in a major field. Questionnaires were mailed to high school teachers who were solo-teaching 'Technology and Home Economics' at high schools in Gyeonggi Do. Data from 83 respondents were used for the final analysis. The findings were as follows: First, it was determined that teachers tend to be more active when teaching subjects in which they have majored than subjects in which they have not. Teachers who have majored in home economics were most active when teaching home economics, followed by technology major teachers teaching technology, home economics major teachers teaching technology and technology major teachers teaching home economics, the last group exhibiting the least willingness to teach. Similarly, all teachers exhibited less confidence in areas not relevant to their majors, and confidence especially was lower while teaching practical skills versus theories. Teachers also were found to be less satisfied with teaching subjects outside of their majors. Second, analyzing technology majors currently teaching home economics and comparing those who have and have not participated in training sessions for home economics teaching, we found that 1) technology majors with such training feel that the training experience helped them in preparing various teaching media and in their evaluation of students' understanding of basic concepts and practices; 2) these training programs increased teachers' confidence teaching theories, but not practical skills; and 3) after they had participated in training programs, teachers' satisfaction increased in terms of producing teaching agendas and selecting textbooks and teaching media for their classes. However, training programs were found to have no effect on home economics majors who had participated in technology training programs, in terms of teaching behaviors, confidence or satisfaction teaching technology.

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A Study on the Administration for the Han River Water Quality Control (漢江 水質保全 行政에 관한 硏究)

  • Kim, Kwang Hyop
    • Journal of Environmental Health Sciences
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    • v.10 no.2
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    • pp.9-40
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    • 1984
  • This thesis purports to overview the diverse administrative and organizational factors and plannings developed by the government organizations, municipal or otherwise, to tackle the Han River water pollution issues in the past years. This thesis also looks into the ever-worsening Han River water pollution problems, in particular, in terms of the various government plans ostensibly designed to reduce the pollution level but with little success. Also dealt with are the efficiencies with which the laws and decrees on water pollution the administrative organizations put to use in the prosecution of the diverse antiwater pollution projects involving the Han River basin. From the early 1960's up to the 1970's the government had concentrated on the growth-oriented economic policy with the result that little attention had been paid to the water pollution and other environmental issues that are bound to arise from the massive economic growth. Belatedly, the five-year Hah River Development Project was initiated in 1982 with emphasis on reducing the water pollution level at Hah River to the minimum. The following are the gists of the thesis and recommendations for the future antiwater pollution plans by the administrative organizations: 1. Documents to date indicate that the irrigation projects along the Han River area had been the main focus of attention during the Yi Dynasty and under the Japanese rule of the country. 2. Despite that the water pollution issue became the subject of many debates among the academic and research institutions in the 1960's and in the 1970's, the administrative organizations in charge of the Han River water quality control failed to come up with a concrete plan for the river's water quality control. 3. Nevertheless, the water pollution of the Han River area in fact began in the 1950's, with the unprecedented concentration into Seoul of population and the industrial facilities on a larger scale, in particular, enforced by the government's strong growthoriented policy in its Economic Development plans in the 1960's. 4. Starting in the 1960's, the Han River water pollution level dramatically increased, but the government was reluctant to promulgate or put into effect strong measures to curb the many factors contributing to the river water pollution, thus worsening the environmental issues along the Han River basin. 5. The environmental protection law and other laws and decrees relating to the antiwater and air pollution issues that were subsequently put into effect underwent so many changes that efficient anti-water pollution policies could not be effected for the Han River basin. The frequent organizational reshuffle within the administrative units concerned with environmental problems has resulted in the undue waste in personnel management and finance. 6. The administration on the environmental protection could not be efficiently carried out due to the organizational overlapping. Under the existing law, frequent organizational frictions and inefficiency are bound to occur among the central government offices themselves, as well as between the central government and the Seoul city administration, and among the city's administrative offices over the conservation of the Han River basin and over the river's anti-water pollution issue. 7. In the planning and prosecution of the Han River project, political influences from the president down to the lower-level politicious appear to have been involved. These political influences in the past had certainly had negative influence on the project, nevertheless, it appears that in the recent years, these political influences are not all that negative in view of the fact that they serve as a positive contributing factor in developing a better water quality control project along the Han River basin. The following are a few recommendations based on the data from the thesis: First, officials in charge of the Han River water quality control should pay attention to a careful screening of the opinions and recommendations from the academic circles and from the public should be made so that the government could better grasp the core issues in the environmental problems that require preventive and other necessary measures. Second, vigorous redistribution policies of population and industrial facilities away from the Seoul area should be pursued. Third, the government should refrain from revising or revamping too frequently the laws and decrees on the anti-water pollution, which is feared to cause undue inconveniences in the environmental administration. Fourth, a large-scale streamlining should be made to the existing administrative organization in an effort to do away with the inter- and intra-organizational friction. It is recommended that a secretariat for the Hah River basis conservation be established. Fifth, High-level administrative officials, with a thorough knowledge and vision on the Han River water quality control, should be prepared to better deal with the budgeting and personnel management for the Han River water pollution control not only at the control government, but also at the Seoul city municipal government levels. Environmental issues should be kept distinct from political issues. Environmental issues should not serve as a window-dressing for sheer political purposes. Sixth, the Hah River proiect should also include, along with the main Han River basin, those areas covering North Han River, South Han River, and the tributaries to the main river basin. The 'Han River Basin Water Quality Control Board' should be established immediately as a means of strengthening the current Han River basin water quality control policy. Seventh, in drawing up the Han River proiect, the administrative officials should be aware that Han River basin is a life line for those people in the region, providing them with not only a sheer physical space, but with a psychological living space for their everyday life.

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Effect of Reduced Glutathione on Non-Protein Sulfhydryl and Non-Protein Disulfide of the Mouse Liver in Vitro (Reduced Glutathione의 In Vitro 첨가(添加)가 마우스간조직(肝組織)의 내재(內在) NP-SH 및 NP-SS에 미치는 영향(影響))

  • Oh, Sang-You
    • The Korean Journal of Physiology
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    • v.7 no.2
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    • pp.9-16
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    • 1973
  • In view of the recent knowledge on the radioprotective action of reduced glutathione (GSH), the present study was designed the elucidate the effect of some concentrations of GSH on the levels of intrinsic non-protein sulfhydryl (NP-SH) and non-protein disulfide (NP-SS) of the mouse liver incubated at 4, 25 and 37C in vitro, respectively. The liver slice of the mouse was incubated at 4, 25 and 37C in the medium composed of 100 ml of Krebs-Ringer phosphate buffer (KRP) with the addition of 10, 20 and 30 mg of GSH, respectively. Measurement of NP-SH and NP-SS was made at 5, 30 and 60 min during the course of the incubation, and the results were compared with the controls which were incubated only in KRP medium, and the normal. The results thus obtained are summarized as follows: 1. When the mouse liver slice was incubated at 4C, the values of both NP-SH and NP-SS of the control and the group where 10 mg of GSH was added to the incubation medium were similar to those of the normal group, and the increase of NP-SH and NP-SS with the increased concentrations of GSH was not prominent. 2. When the liver slice was incubated in the concentrations of GSH 20 mg/100 ml KRP and GSH 30 mg/100 ml KRP at 25 C, the rate of increase of both NP-SH and NP-SS was proportional to the increase of GSH concentration. In the group where 10 mg of GSH was added to the incubation medium, the value of NP-SH and NP-SS reached the highest value at 30 min, but a tendency of decrease was observed at 60 min. 3. The rate of increase of NP-SH and NP-SS of the liver was most marked of all the group. studied when the incubation temperatuse was elevated to 37C, and the increase was proportional to the concentration of GSH and the incubation time.

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