• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.4
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• pp.479-484
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• 2000

The conventional treatment of skeletal class III malocclusion has been focused on the application of orthopedic forrce primarily to the mandible. Thus moderate Class III malocclusions can be corrected by the anterior displacement of the maxilla and maxillary dentition, possibly by restricting the growth of the mandible or by changing its direction. The patients having skeletal Class III malocclusion were treated with removable appliance & fixed appliance for detailed tooth movement and the following results were observed: 1. The anterior crossbite was corrected. 2. The forward and downward growth of the maxillary complex was obtained. 3. The lingual tipping of the mandiblar incisors was performed and the mandible was rotated in the clockwise direction.

• Journal of Periodontal and Implant Science
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• v.23 no.3
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• pp.535-563
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• 1993

New techniques for regenerating the destructed periodontal tissue have been studied for many years. Current acceptable methods of promoting periodontal regeneration alre basis of removal of diseased soft tissue, root treatment, guided tissue regeneration, graft materials, biological mediators. Platelet-derived growth factor (PDGF) is one of polypeptide growth factor. PDGF have been reported as a biological mediator which regulate activities of wound healing progress including cell proliferation, migration, and metabolism. The purposes of this study is to evaluate the possibility of using the PDGF as a regeneration promoting agent for furcation involvement defect. Eight adult mongrel dogs were used in this experiment. The dogs were anesthetized with Pentobarbital Sodium (25-30 mg/kg of body weight, Tokyo chemical Co., Japan) and conventional periodontal prophylaxis were performed with ultrasonic scaler. With intrasulcular and crestal incision, mucoperiosteal flap was elevated. Following decortication with 1/2 high speed round bur, degree III furcation defect was made on mandibular second(P2) and fourth(P4) premolar. For the basic treatment of root surface, fully saturated citric acid was applied on the exposed root surface for 3 minutes. On the right P4 20ug of human recombinant PDGF-BB dissolved in acetic acid was applied with polypropylene autopipette. On the left P2 and right P2 PDGF-BB was applied after insertion of ${\beta}-Tricalcium$ phosphate(TCP) and collagen (Collatape) respectively. Left mandibular P4 was used as control. Systemic antibiotics (Penicillin-G benzathine and penicillin-G procaine, 1 ml per 10-25 1bs body weight) were administrated intramuscular for 2 weeks after surgery. Irrigation with 0.1% Chlorhexidine Gluconate around operated sites was performed during the whole experimental period except one day immediate after surgery. Soft diets were fed through the whole experiment period. After 2, 4, 8, 12 weeks, the animals were sacrificed by perfusion technique. Tissue block was excised including the tooth and prepared for light microscope with H-E staining. At 2 weeks after surgery, therer were rapid osteogenesis phenomenon on the defected area of the PDGF only treated group and early trabeculation pattern was made with new osteoid tissue produced by activated osteoblast. Bone formation was almost completed to the fornix of furcation by 8 weeks after surgery. New cementum fromation was observed from 2 weeks after surgery, and the thickness was increased until 8 weeks with typical Sharpey’s fibers reembedded into new bone and cementum. In both PDGF-BB with TCP group and PDGF-BB with Collagen group, regeneration process including new bone and new cementum formation and the group especially in the early weeks. It might be thought that the migration of actively proliferating cells was prohibited by the graft materials. In conclusion, platelet-derived growth factor can promote rapid osteogenesis during early stage of periodontal tissue regeneration.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.6
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• pp.245-251
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• 2015

We have applied mechanical alloying (MA) to produce soft magnetic composite material using a mixture of elemental $Fe_2O_3$-Mg powders. An optimal milling and heat treatment conditions to obtain soft magnetic ${\alpha}$-Fe/MgO composite with fine microstructure were investigated by X-ray diffraction, differential scanning calorimetry (DSC) and vibrating sample magnetometer (VSM) measurement. It is found that ${\alpha}$-Fe/MgO composite powders in which MgO is dispersed in ${\alpha}$-Fe matrix are obtained by MA of $Fe_2O_3$ with Mg for 30 min. The saturation magnetization of ball-milled powders increases with increasing milling time and reaches to a maximum value of 69.5 emu/g after 5 h MA. The magnetic hardening due to the reduction of the ${\alpha}$-Fe grain size by MA was also observed. Densification of the MA powders was performed in a spark plasma sintering (SPS) machine at $800{\sim}1000^{\circ}C$ under 60 MPa. X-ray diffraction result shows that the average grain size of ${\alpha}$-Fe in ${\alpha}$-Fe/MgO nanocomposite sintered at $800^{\circ}C$ is in the range of 110 nm.

• Korean Business Review
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• v.21 no.2
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• pp.195-214
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• 2008

In 2004, in order to create core competences and major growth drivers for endogenous regional developments, the Korean government adopted the policies for establishing regional innovation systems, The main organization for the policies is the regional innovation council which is composed of diverse groups of scholars, professionals, and government officials. The regional innovation council of Kang-won Province consists of a couple of sub-divisions such as Operation Committee, Administration Office, Planning and Moderation Department, Strategic Industry Department, Culture and Tourism Industry Department, Regional Industry Department, and Regional Human Resource Development Department. The primary roles and jobs are planning, reviewing, evaluating and finalizing regional innovation policies. However, because of conflicts with local government, insufficient budget problems, organization structure problems, and decision making process problems, the regional innovation councils could not perform their original roles and functions. They could not adopt radical or non-traditional strategies. Although it's failure, a lot of people recognize the importance of regional innovation councils' roles and functions, I believe there would be another regional innovation councils coming continuously which would be take more important roles and have more power over budgeting problems. The purpose of this article is to identify the primary sources of strategies and organization structure problems of the previous regional innovation councils and to provide a couple of answers. In this paper, the author primarily analyze the problems of the Kang-won innovation council. A couple of answers to the desirable organization structures and the desirable roles of regional innovation councils will be presented for discussion.

• Clinical and Experimental Pediatrics
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• v.46 no.7
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• pp.687-694
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• 2003

Purpose : Regeneration and repair after ischemic renal injury appears to be modulated by circulating or locally produced growth factors. This study examined the changes of serum insulin like growth factor(IGF-I) and renal expression of IGF-I and II, vascular endothelial growth factor(VEGF), transforming growth $factor-{\beta}$($TGF-{\beta}$), and connective tissue growth factor(CTGF) during the active regeneration period after acute ischemic injury. Methods : Sera and kidney tissue samples(whole kidney, cortex, outer medullae and inner medullae) were obtained before and after one, three, five and seven days of 40 minutes bilateral renal pedicle clamping. Acute renal failure was assessed by measuring the concentration of serum creatinine. Serum IGF-I level was measured by radioimmunoassay. The mRNA expression in kidney was measured by RT-PCR. The distribution of IGF-I and CTGF was detected by immunohistochemistry. Resuts : Serum IGF-I concentration after one day following acute ischemic renal injury was significantly decreased compared to preischemic value. The mRNA levels of IGF-I, IGF-II, $TGF-{\beta}1$ and VEGF in whole kidney were temporally decreased on day one of ischemic injury. IGF-I and IGF-II expressions in outer medullae were significantly decreased on day one after ischemic injury. $TGF-{\beta}1$, CTGF and VEGF expressions were markedly decreased in medullae after one day of ischemic injury compared to other kidney sections. IGF-I was markedly decreased in cortical tubules on day one of uremic rat. CTGF was markedly increased on tubule within three days of ischemic injury. Conclusion : These findings suggest that IGFs, $TGF-{\beta}1$ and CTGF may involve in the pathogenesis or the recovery from acute ischemic renal injury.

• The Journal of the Korea Contents Association
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• v.11 no.3
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• pp.351-367
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• 2011

Few previous researches have been studied in terms of franchisees' perceptions of franchisors' entrepreneurial activities within the boundary of restaurant franchising industry settings. The sampling frame for this study included 605 restaurant franchisees in the business-format franchising system in Korea and data were collected from 1 October 2009 to 28 February 2010. This study, from franchisees' views, investigated the relationship among franchisors' entrepreneurship, external environment, organizational structure(mechanistic-organic) and managerial performance, with structural equation modeling(SEM). The research findings were, firstly, external environment positively affected entrepreneurship which positively affected market orientation and managerial performance, and secondly, market orientation made franchisors select organic structure and heighten managerial performance. Also, external environment led franchisors to adopt organic structure and aggravated their managerial performance. The implications of these findings were as follows. Firstly, the more franchiors had initiatives, innovatedness and risk-taking attitudes, the higher they had managerial performances and market orientation. Secondly, franchisors should keep and heighten market share with keeping in mind with customer orientation, competition orientation, harmony between departments, long-term orientation and profitability. Thirdly, continuous and cautious environmental scanning was necessary because external restaurant environment made organizational structure being changed and managerial performance being aggravated.

• Korean Journal of Head & Neck Oncology
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• v.30 no.1
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• pp.1-4
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• 2014

배경 및 목적 타액선 선양낭성암종은 느린 성장 속도와 늦은 원격 전이를 특징으로 하는 드문 상피성종양이다. 본 연구는 다양한 임상 병리학적 변수를 통해 선양낭성암종의 원격 전이에 영향을 주는 인자를 조사하고자 하였다. 대상 및 방법 1999년 10월부터 2011년 12월까지 본원 이비인후과에서 타액선 선양낭성암종으로 진단되어 치료 받은 44명(남자 19명, 여자 25명)을 대상으로 원격전이를 유발하는 위험 인자를 조사하였다. 8명의 환자는 배제 기준에 따라 제외하였다. 환자의 평균 연령은 54세였다. 환자의 병리 보고서, 종양의 크기, T 병기, 수술 절제연의 종양 존재 유무, 신경 조직 침습, 림프절 전이가 조사되었다. 결 과 15명의 환자가 원격전이가 있었으며 21명은 원격 전이가 없었다. 원격 전이를 유발할 수 있는 여러 인자들을 비교하였을 때, 원격 전이는 수술 절제연의 종양 세포 잔존(p=0.014), 종양의 크기(p=0.038), 진행된 T 병기(p=0.024)가 통계적으로 유의하게 연관성이 있었다. 림프절 전이와 신경 조직 침습은 원격 전이와 연관이 없었다. 결 론 종양의 크기, 진행된 T 병기, 수술 후 절제연의 종양 세포 잔존은 원격 전이의 예측 인자로 생각된다. 따라서 이에 해당하는 환자의 경우 더욱 철저한 관리 및 경과 관찰을 요한다.

• Journal of Chest Surgery
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• v.39 no.2 s.259
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• pp.166-170
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• 2006

Myxofibrosarcoma represents one of the most common soft tissue sarcomas of the extremities in adult and elderly patients. However, it only rarely occurs in the chest wall. A 58 years old woman presented with a huge painless lump (8 ${\times}$ 6.5 cm) in the right lower parasternal area which recurred a few months following excision from General surgery of our hospital. Histology showed an infiltrative deep seated dermal and subcutaneous tumor. It had a distinctive lobular growth pattern with prominent myxoid change and moderate cellularity. Tumor cells were spindleshaped with varying degrees of pleomorphism and frequent mitotic figures. Numerous blood vessels with curvilinear growth pattern were also seen. Immunostains for S-100, CD68, Mac 387, and FX IIIa were all negative, but positive for Vimentin. The histologic feature was of an intermediate grade myxofibrosarcoma. Wide excision was performed and recovered in good condition without any physical disabilities and was discharged at one month later. Currently she is waiting for the skin graft without chemotherapy and radiotherapy.

• Journal of Practical Agriculture & Fisheries Research
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• v.23 no.1
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• pp.117-128
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• 2021

The skeletal muscle development of Hanwoo steer has been processed in the prenatal and postnatal periods. Bovine satellite cell located in perimysium of muscle tissues has differentially distributed in peripheral tissues. The study of postnatal development of satellite cells can help understand the genetic and functional regulation of meat characteristics. Factors affecting muscle size increase are related to the accumulation of DNA or synthesis of RNA proteins. In this study, we observed muscle development and differentiation after culturing bovine satellite cells derived from longissimus dorsi and semimembranosus regions of Hanwoo muscle tissue. In addition, RNA sequencing data were analyzed for differentially expressed genes (DEG) involved in intracellular muscle development and growth. The DEG of the two muscle tissues were compared according to 1day, 2day, 4day, and 7day. The overall gene expression level was confirmed by the heat map. Gene Ontology (GO) classification method was used to compare the expression level of gene groups affecting LD and SM development. The histology of GO was consistent with the time-cause change of LD and SM cell morphology. SM showed more active skeletal muscle development than LD. Even within the same time, SM expressed more genes than LD, thus synthesizing more muscle fibers

• Journal of Science and Technology Studies
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• v.6 no.1 s.11
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• pp.119-152
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• 2006

This paper deals with the historical development of research community in Korea. As the former studies of the korean scientific community show, the government supported institutes played an important role in the formation of research community. Therefore the theme of this study is concerned with the historical development of the government supported institutes and the features of their researcher group. In this paper following questions will be answered: How the social status of these researcher group is changed, what kind of response on social problems or national politics they had, and which characteristic they showed with regards to the identity problem. After the korean liberation the government institutes, such as the Chungang Kongop Yonguso(industrial research center)and the Korean Atomic Energy Research Institute, contributed to the development of the first generation of research group. However this research group could hardly identify themselves as researcher, because they spent much time on testing, evaluation or education. The identity problem is also resulted from the deficiency of authority as research institute. The status of researcher had no difference from that of civil servant. With the establishment of KIST the korean research community came into blossom. The government supported institutes, which were founded after the model of KIST, allowed quantitative and qualitative growth of research community. Thanks to the guarantee of institutional authority and the new reward system, the researcher could get respect and improve its social status. During this period the researcher volunteered to help the government policies. We can find often the nationalistic statements in the research community. During 1990s the research group demonstrated different behaviors and attitude toward the government. The nationalistic ideology disappeared. Instead of that, the research group criticized the government policies and took actions against the government. Those changes are related with the lowered position of government supported institutes.