구내 접근법에 의한 하악골 골절 치료에 대한 임상적 고찰

정성훈,박형식,권준호 大韓顎顔面成形外科學會 1989 Maxillofacial Plastic Reconstructive Surgery Vol.11 No.1

This is a retrospective study on the transoral approach to open reduction of the Mandibular fractures. Our study was based on a series of 64 patients with mandibular fractures among 99 patients of facial bone fractures who had been treated by transoral approach with or without extraoral approach at Department of Oral and Maxillofacial Surgery, Yonsei Medical Center, Yonsei University from January 1981 to October 1988. We studied favorite sites of open reduction, fixation methods, results and prognosis related to transoral approaches of Mandibular fractures, and which compared with extraoral approaches. The results obtained are as follows : 1. The transoral open reduction was used more frequently in Mandibular fractures(64.6%) than Midfacial bone fractures(35.4%). Among 64 patients of mandibular fractures, 47 patients(73.4%) were treated only by transoral approach and others(26.6%) were treated by both trans and extraoral approach. Among 92 sites of mandibular fractures 75 sites(81.5%) were treated by transoral approach and 17(18.5%) were treated by extraoral approach. 2. The most favorite site for transoral approach compared with extraoral approach was symphysis(100%), and Angle(62.5%) was next in order of frequency on Mandibular fractures. 3. Direct Interosseous Wiring(DIW) was most commonly used for fixation(64.6%) and Miniplate osteosynthesis was used next in 28.1%. 4. Simple(39.1%) and Compound(52.2%) fractures were frequently indicated for transoral approach, however comminuted fractures were rarely indicated. 5. The direction of fracture lines on Angle of the mandible did not influence to determine whether transoral approach should be selected or not. However this area seemed to be more difficult to reduce exactly by transoral procedure than other areas because simultaneous superior and inferior fixation was applied predominantly on this area. 6. The success rate of reduction and fixation analyzed from us was more excellent in Direct Interosseous Wiring(29/53=54.7%) than in Rigid Internal Fixation(9/29=31.0%). But it might be depended upon various factors as like as sugeon's skill. 7. The postoperative complication due to transoral open reduction of mandible was not high(12.0%) and this rate was similar with other published reports.

댐퍼붙이 거위목바이트를 使用하는 切削系의 動的 安定性에 關한 硏究

李炯植,鄭準基,盧光春 연세대학교 산업기술연구소 1982 논문집 Vol.14 No.2

The effect of the damped goose-neck tool upon the dynamic stability of machine tool was investigated. The dynamic stability of machine tool is directly related to the chatter in the metal cutting process. By the test of the dynamic characteristics for the damped goose-neck tool, theoretical approach of dynamic stability of machine tool is identified. It's results are compared with the results of actual cutting test. And the dynamic stability of machine tool is improved by the higher elasticity and the increase of damping coefficient for the damped goose-neck tool.

Dimethylformamide가 Mouse 肝細胞의 微細構造에 미치는 影響

이형록,정호삼,이규식 한양대학교 의과대학 1985 한양의대 학술지 Vol.5 No.2

Dimethylformamide (DMF) has been widely used in the synthetic textile industry as an organic solvent. However, it is known that DMF irritates to skin and mucous membranes and causes several toxic symptoms when dermal and respiratory exposure to DMF is prolonged. It is supposed that DMF provoked toxic reaction in the liver during the metabolic process of the DMF-injected experimental animal. Therefore, the authors observed changes cytoplasmic organelles of the hepatic parenchymal cells in order to demonstrate the effect of DMF on the mouse liver. Healthy male mice of ICR strain were used in this experiment and the weight of the experimental animals were around 20gm. The animals of the experimental group were administered DMF diluted in the water for injection, by intraperitoneal injection in a dose of 1.5ml per kg of body weight in a volume of 0.2ml. The animals of the control group were amdinistered only water for injection. The experimental animals were killed at intervals of 6, 12, 24 and 48 hours after administration of DMF, respectively. Liver specimens of 1mm³ size were prefixed in the 2% glutaraldehyde-2.5% paraformaldehyde phosphate buffer solution (pH 7.2) and post-fixed in the 1% osmic acid. After specimens were dehydrated and embedded in the epon 812, ultrathin sections(600-800A°thickness) were made and double stained with uranyl acetate and lead citrate. These preparations were observed with JEM 100B electron microscope. The results obtained were as follows: 1. Cisternae of rough endoplasmic reticulum were intensely dilatated and fragmented partly. 2. Smooth endoplasmic reticulum was markedly proliferated and glycogen particles were markedly decreased or depleted. 3. The atrophies of the Golgi complex were found. 4. Primary lysosomes and secondary lysosomes-residual bodies, autophagic vacuole and multivesicular bodies were increased in number. 5. Numerous lipid droplets of irregular size were produced. Consequently, it is concluded that DMF would induce the degenerative changes in cytoplasmic organelles of the hepatic parenchymal cell in the mouse.

Centerless Feeder 장치의 개발

강형모,권경우,김기길,정의식,허영환 한밭대학교 산업과학기술연구소 1994 논문집 Vol.2 No.-

This paper presents results of the development of centerless feeding system which are applicable to bearing metal processes. As a result, the feeding system can be applied to automatic surface finishing on the bearing metal process such as bush, and has greatly effects on the increase of the prodnctiving and the decrease of the man power an effect on increase the productivity and decrease the man power and effect on increase the productivity and decrease the man power of the bush machining process.

非線形 理論에 依한 채터 解析

이형식,정준기,박태형 연세대학교 산업기술연구소 1983 논문집 Vol.15 No.2

The chatter analysis has been studied by many authors using non-linear. In this study, the stability chart obtained from experimental work with a lathe was qualitatively compared with the result of chatter analysis by non-linear theory. Experimental results verify that the stability of the machining process is affected by the width of cut in the following manner. As the chip width is increased from zero with the rotational speed of the workpiece kept constant, three ranges are distinguished; (a) unconditionally stable range, (b) conditionally stable range, (c) unstable range. In the conditionally stable range the system is stable for small disturbances but unstable when these exceed a certain level. When the chatter occurs, the amplitude initially increases and stabilizes itself at a finite level. This phenomenon agrees well with the analysis of non-linear theory qualitatively.

熱間 알미늄 押出型材의 型材係數에 관한 연구

박정수,이형식 연세대학교 산업기술연구소 1975 논문집 Vol.6 No.1

In the hot extrusion of aluminum alloys for architectural uses, a wide variety of extrusion shapes are encountered under various requirements necessitating it different operational conditions to adopt. However, the prevailing cost estimate for the extrusion shapes practised so far among the extruders in this country has been a unique cost per kilogram without regard to the geometric configuration and its operational condition, which has presented itself as one of the most unreasonable aspect in the plant operation and for the estimation of their prices. In this study, a shape factor that indicates the degree of relative complexity in the extrusion process for every extrusion shape reflecting its geometric configuration and operational condition was established, and the relationship between the shape factor and the productivity was observed through the practical operation. It was found that a logarithmic relationship was existing between the shape factor and the extrusion output per hour, where the output being decreased with the increase of the shape factor. And also, empirical equations were established for obtaining the extrusion output per hour with the variable of the shape factor. Meanwhile, the extrusion recovery, the life span of die and the fuel and power consumption in the extrusion were analyzed, which, together with the extrusion time, were used in establishing a formula for an overall cost estimate for every extrusion shape. There were marked differences in the overall costs of aluminum shapes, and the costs were dependent on the shape factor, type of die and the applicable dimensional tolerances. Among them, the shape factor was found to be the most dominant agent in the cost estimate. Comparing with the conventional method of unique cost estimation, the formulas for calculation of the overall costs for every shape which were newly established in this study provide the most reasonable basis for the pricing of extruded aluminum shapes, thereby making it possible to benefit both the manufacturers and the consumers.

電氣痙攣型衝擊이 白鼠 海馬의 GABA와 Glutamate 代謝에 關與하는 酸素의 活性度에 미치는 影響에 關한 硏究

李昌仁,李定均,金容植,金亨來 서울醫大 1991 精神醫學 Vol.16 No.1

쇼트피닝 가공한 평기어의 피로특성

정성균,정동건,박충식,김태형,이재헌 서울産業大學校 2002 논문집 Vol.53 No.1

In this paper, the effect of shot peening on the fatigue characteristics have been investigated. Two types of specimens were used to obtain the experimental results. One type of specimen was made by machining and heat-treating SCM415 steel. The other type of specimen was made by machining, heat-treating, and shot peening SCM415 steel. The hydraulic testing machine was used to do the fatigue test (R=0.1, 10Hz). The experimental results show that the fatigue life and strength of shot peened gear were largely improved compared with the unpeened gear.

보신 관광에서 감염된 수입성 Sparganosis 1예 : Intake of Thailand Snake during Trip

서환조,박명재,고경식,백영한,조유정,양현종,류경남,정형근,전정열 대한감염학회 1992 감염 Vol.24 No.1

Human sparganosois was reported more than 100 cases in Korean population. However no case reported yet in Korea as a patient was infected by sparganum from other geographical area, such as Thailand. The case we are reported here is a 38 year-old Korean male who had been suffered from mass being a small, round and soft consistance in upper portion of his right thigh. The patients stated that he had an opportunity to eat living snake in Bangkok, Thailand during trip. As therapy praziquantel (75㎎/㎏/day) was given p.o. for 14 days, but in vain to cure. Following medical treatment, surgical exicision was performed to remove a alive, soft, whitish-milky, mobile and elongated sparganum. Serlogical test by micro-ELISA for sparganum-specific antibody revealed a high serum antibody level of absorbance 0.67 (positive criterion: absorbance 0.22).

Hairy Root Culture of Polygonum tinctorium for Indirubin Production in a Split-flow Air-lift Bioreactor

Chung, Choong Sik,Hong, Sung Hyun,Kim, Chang Heon,Lee, Youn Hyung,Lee, Hyong Joo,Chae, Young Am,Chung, In Sik 한국응용생명화학회 2000 Journal of Applied Biological Chemistry (J. Appl. Vol.43 No.2