방사선조사가 설의 개방성창상치유에서 섬유아세포의 재형성에 미치는 영향에 관한 연구

최순철,박태원,유동수,이진구 大韓口腔顎顔面 放射線學會 1997 Imaging Science in Dentistry Vol.27 No.1

Radiation-impaired wound healing in animal experiments was believed to be an another logical experimental model to understand the wound healing mechanism in patients. The purpose of this study was to reveal the block point which would result in impaired healing. Twenty four rats(Sprague-Dawley strains) were divided into two groups according to the time interval between irradiation and wounding. Group I, observing the healing effect on the lst day and GroupⅡ are the healing effects on the 7th days after irradiation to the wound of the rat tongue. Experimental animals were sacrificed 3, 6, 12, and 24 hours after wounding. The specimens were examined by the light microscope and transmission electron microscope. The following results were obtained 1. Fibroblasts in both groups showed degenerative changes which were dilated mitochondria and rER, reduced microorganelle, vacuoles and little cytoplasmic process. 2. Average length between bands and quantity of the newly produced collagen fibers around fibroblasts remained unchanged against control group. 3. The severity of degenerative change of the fibroblast and impairment of wound healing including shortening of the thickness of collagen fibers were more severe in the group Ⅱ than in the group I.

크롬-망간鋼에서 析出된 複合炭化物의 粗大化 特性에 관한 硏究

崔鎭源,李相允,安哲佑 東亞大學校 大學院 1987 大學院論文集 Vol.12 No.-

This study has been carried out to investigate into the Ostwald Ripening behaviors of comples carbide particles precipitated in Cr-Mn steel during spheroidizing treatment at a range of temperature 650℃ to 710℃ after standarding the initial particle size distribution. The results obtained from the experiment are as follows; 1. Optical micrographs have shown that the precipitated particles mostly grow along grain boundaries with their shapes being irregular and that particles within the ferrite matrix appear to be small spheres. 2. Average particle size measurements have presented that a reciprocal of the slopes of three straight lines obtained from the relation between the log of average particle radius and the log of spheroidiaing time for 650℃, 680℃ and 710℃ approaches a value of 3.5 and that the growth of complex carbide particles occurs by a diffusion controlled mechanism combined with volume diffusion and grain boundary diffusion. 3. In has been found from the measured values for the average particle radius and the number of particles per unit volume that the average value of activation energy is 48.3Kcal/mole, which shows that the coarsening of complex carbide particles is governed by the interdiffusion mechanism of Fe, C, Cr and Mn atoms. 4. X-ray diffraction analysis has shown that the complex carbide particles precipitated during spheroidizing treatment are of two types, (Fe, Cr, Mn)₃C and (Fe, Cr, Mn)? C₃. 5. Experimentally measured particle size distribution curves approach the steady state distribution curve obtained for volume diffusion but their width and height are relatively broader and lower.

프레탈^(R)정(실로스타졸 50mg)에 대한 실로졸^(R)정의 생물학적 동등성

최한곤,권기철,이승호,김학미,박병주,유봉규,이종달,이경희,하정희,우종수,박인숙,최진석,용철순 한국병원약사회 2003 병원약사회지 Vol.20 No.1

Bioequivalence of two cilostazol tablets, the Pletaal^(R)(Korea Otsuka Pharmaceutical Co., Ltd.) and the Cilozol^(R)(Hanmi Pharmaceutical Co., Ltd.), was evaluated according to the guideline of KFDA, Sixteen normal male volunteers(age 20~29 years old) were divided into two groups and a randomized 22 cross-over study was employed. After two tablets containing 50㎎ of cilostazol were orally administered. blood was taken at predetermined time intervals and the concentration of cilostazol in plasma was determined with an HPLC method using UV detector. The pharmacokinetic parameters(C_(max), T_(max) and AUC_(t)) were calculated and ANOVA was utilized for the statistical analysis of parameters. The results showed that the differences in C_(max), T_(max) and AUC_(t) between two tablets were 4.99%, 1.74% and 7.68%, respectively. The powers(1-β) for C_(max), T_(max) and AUC_(t) were83.92%, 80.12% and 85.03%, respectively. Detectable differences(Δ) and confidence intervals were all less than 20%, and confidence interval of all the parameters were also less than 20% at the significance level(α) of 0.05. All of these parameters met the criteria of KFDA for bioequivalence, indicating that Cilozol^(R) tablet is bioequivalent to Pletaal^(R) tablet.

蓄熱用 TMA 包接化合物의 熱物性에 關한 實驗 硏究(Ⅰ)

최영범,한영옥,하옥남,김병철,김진흥 조선대학교 동력자원연구소 1996 動力資源硏究所誌 Vol.18 No.2

This paper presents the test-tube experimental results of thermal properties of TMA clathrate compounds for latent heat storage applications. The results are : ⅰ) subcooling in TMA clathrate compound is the lower than water, ⅱ) Phase change temperature in TMA clathrate compound is the higher than water. ⅲ) Latent heat of 25wt% TMA clathrate compounds of 220.4kJ/㎏K appear to be maximum. ⅳ) Comparing with water, volume of TMA clathrate compounds decreased as the phase change. ⅴ) TMA clathrate compounds precipitated because of increase of density as phase change. Thus, TMA clathrate compounds are found to be the promising compounds for the heat storage from the viewpoint of thermal property.

Homocysteine과 대사증후군의 관계

최진욱,김선현,염창환,정규철 관동대학교 의과학연구소 2006 關東醫大學術誌 Vol.10 No.1

전유전체 서열 분석과 가시화를 위한 워크벤치 개발과 응용

최정현,진희정,김철민,장철훈,조환규 한국유전학회 2002 Genes & Genomics Vol.24 No.2

An increasing number of genome sequencing projects results in explosive growth of whole genome sequences. Furthermore the number of studies on the functions of individual genes has also been rapidly increased. However on-memory algorithms are not applicable to the analysis of whole genome sequences, since the size of individual whole gene a ranges from several million base pairs to hundreds billion base pairs. In order to effectively manipulate the huge sequence data, it is necessary to use the indexed data structure for external memory. In this paper, we introduce the development and application of the workbench for the analysis and visualization of whole genome sequences using string B-tree that is suitable for the analysis of huge data. This system consists of two main parts, the analysis query part and the visualization part. The query system supports various transactions such as pattern matching, k-occurrence, and k-mer analysis. The visualization system helps biologists to easily understand whole genome structure and specificity by various kinds of visualization such as whole genome sequence viewer, annotation viewer, CGR (Chaos Game Representation) viewer, k-mer viewer, RWP (Random Walk Plot) viewer, and map viewer. We can find the relationships among organisms, support gene prediction in a genome, and study the function of junk DNA using our workbench. In this paper, we apply our workbench to investigating specific sequence such as avoided sequence, common sequence, and classifiable sequence.

백서에서 실험적 치아이동시 치조골 흡수에 미치는 Bisphosphonate의 영향 : Biochemical & Histological Observations

최진휴,김종철 전남대학교 치과대학 1998 전남치대논문집 Vol.10 No.1

This study was performed to examine the effect of bisphosphonate, an inhibitor of bone resorption, on the formation of osteoclast and bone resorption during experimental tooth movement. Whether bisphosphonate has a cytotoxicity in high dose was also examined. Eighty-seven male Sprague-Dawley rats, weighing 260-350g, were classified into normal (no appliance + 0.9% NaCl), control (appliance + 0.9% NaCl) and four bisphosphonate-treated (appliance + 0.8, 4, 20 or 100 ㎎/㎏) groups. The maxillary left first molar was moved mesially with the tipping movement using 50-70g of force. Bisphosphonate(etidronate disodium) was injected intraperitoneally with a dose of 0.8, 4, 20, or 100 ㎎/㎏ simultaneously with the application of the orthodontic force. They were killed at day 1, 3, or 7 after the application of the orthodontic force. The activities of serum acid phosphatase and lactate dehydrogenase (LDH) were assayed, and osteoclasts and the degree of bone resorption were examined histologically. The results obtained were as follows: 1. Acid phosphatase activities were significantly higher in the appliance groups, both control and bisphosphonate-treated (4, 20, and 100 ㎎/㎏) groups, at day 1 and 3 than these in normal. At day 1, bisphosphonate-treated(4, 20㎎/㎏) groups showed even higher acid phosphatase than control. However, at day 7, no significant difference was noted between the control and bisphosphonate-treated groups. 2. LDH activities in the 4, 20㎎/㎏ bisphosphonate-treated groups were increased during the experimental periods examined, but there were no significant differences in the 0.8, 100㎎/㎏ bisphosphonate-treated groups. 3. There was no bone resorption at day 1, but severe bone resorption was observed at days 3 and 7 in the control. Bone resorption was reduced by bisphosphonate-treatment at day 3. Bone resorption observed at day 7 was similat between the control and bisphosphonate-treated groups. 4. Few osteoclasts were observed at the alveolar bone in the control and bisphosphonate-treated groups at day1. At day 3, numerous osteoclasts were shown in the control, the degree of which was reduced in bisphophonate-treated groups. These results suggest that the inhibition of the osteoclast formation was not the mechanism of bone resorption by the bisphosphonate-treated during experimental tooth movement. There was no distinct cytotoxicity with a high dose of bisphosphonate. And the drug should be administrated repeatedly to maintain the inhibitory effect of bone resorption.

Molar Uprighting Spring에 의해 발생되는 치조골내의 응력분포에 관한 광탄성학적 연구

최진휴,김종철 전남대학교 치과대학 1990 전남치대논문집 Vol.2 No.1

This study was performed to analyze the effects of forces to the alveolar bone by various molar uprighting spring such as helical uprighting spring, T-loop spring, Modified T-loop spring and open coil spring. The simplified two-dimensional photoelastic model was constructed with a lower left posterior quadrant containing the second molar, the first and second premolars and the canine, with the first molar missing. Several molar uprighting springs were fabricated from 0.017 by 0.022 inch blue Elgiloy and applied to the photoelastic model. Two-dimensional photoelastic stress analysis was performed, and the stress distribution was recorded by photography. The results obtained were as follows ; 1. In all the kinds of the springs, the center of rotation of the mandibular second molar was observed at the apical 1/5-1/6 between the alveolar crest and the root apex. 2. In all the kinds of the spring, the stress induced in the mesial root surface of the manibular second molar was relatively homogeneous but there was some difference in the magnitude of the stress. 3. In the kinds of the springs, the distal crown tipping moment of the second molar was increased in turn as open coil spring, helical uprighting spring, T-loop spring, and modified T-loop spring. 4. The largest extrusive force was occured in the T-loop spring, intrusive force was occured in Modified T-loop spring only, and the largest distal tipping force was occured in open coil spring. 5. In the T-loop spring with activation, the stress induced in the mesial root surface of the second molar was increased gradually from the root apex to the alveolar crest and highly concentrated in the alveolar crest.

Goretex를 이용한 융비술

최진영,민철기,명훈,황순정,서병무,이종호,정필순,김명진 大韓顎顔面成形再建外科學會 2003 Maxillofacial Plastic Reconstructive Surgery Vol.25 No.4

융비술시 실리콘 고무는 다루기 쉽고 조직 반응이 적어 현대 많이 돌출의 합병증이 생길 수 있다. 저자등은 이러한 실리콘의 단점을 보완할 수 있는 goretex를 사용하여 융비술을 시행하고 비첨에 대해서 자가연골을 이식하여 만족할 만한 결과를 얻었기에 goretex가 안면부 연조직의 증강을 위한 이식재료로 적합하다고 생각되어 문헌고찰과 함께 보고하는 바이다. Many different materials have been used to provide augmentation of the nasal dorsum. this include both autogenous and homogenous materials,as well as allografts. Silicone among the artificial materials has been most widely used. The silicone has some advantages and disadvantages. Goretex(expanded polytetra-fluoroethylene) which has widely used in vascular surgery and abdominal surgery can be used for facial soft tissue augmentation. The author presemts 2 cases of nasal augmentaion using goretex with literature review.

회야강(울산)의 식물플랑크톤 군집구조

최철만,배진현 한국환경과학회 2002 한국환경과학회지 Vol.11 No.3

This study was conducted to find the structure of phytoplankton community in the Hoeya river(Ulsan) from March 2000 to February 2001. The taxa of phytoplankton identified included 135 species, 5 divisions, 33 families and 82 genera. Among them, chrysophyta(diatoms) were 63 species(46.7%), chlorophyta(green algae) 47 species(34.8%), pyrrophyta(dinoflagellates) 13 species(9.6%), cyanophyta (cyanobacteria) 8 species(5.9%) and euglenophyta(euglenoids) 4 species(3.0%) respectively. Ecological important species is called frequently appearing species, red tide causative species, seawater species and pollution indicator. 22 species including Aulacoseira granulata were recorded frequently appearing species. 19 species including Ceratium furca were recorded as red tide causing species. And the pollution indicators were 33 species including Actinastrum hantzschil var. fluviatile. The highest standing crops were 3,103,441 cell/ℓ in August at the RW-1 and the lowest 1,245 cell/ℓ in January at the RW-5. In the community analysis, the dominanance indices ranged from 0.34(October, RW-2) to 0.94(January, RW-1) and the diversity indices from 0.50(May, RW-2) to 2.57(September, RW-2). The saprobic indices were 2.43 in RW-1, 2.41in RW-2, 2.375 in RW-3, 2.40 in RW-4, 2.43, in RW-5. Therefore, these areas were investigated "β-mesosaprobic". According to the similarity index among the stations, these areas were defined as residential district areas(RW-2 and RW-3), lower part of the dam (RW-1) and seawater areas(RW-4 and RW-5).