• 대한치과의사협회지
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• 제48권6호
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• pp.454-458
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• 2010

Dental caries is one of the most common chronic diseases in the world, which are caused by complex actions of oral such factors as the bacteria, food, tooth, saliva and other factors. Although this is one of the typical oral diseases, we can acquire a high prophylactic effect by use of proper prophylactic measures and management. At the beginning of the 1940s, fluorine was first introduced to prevent dental caries which now is widely used. The fluorine application effects are varied from different concentrations and categories of fluorine, and different application method and frequency, etc. There is great debate on the best application method at the present. Dental clinics use iontophoresis as the application method and use it clinically. It uses APF (1.23%, Acidulated phosphate fluoride, APF) and uses 2% NaF so as to encourage more absorption of fluorine. Recently, fluoride varnish, which uses admixture mucus of colophony resin into 5% NaF, and a variety of forms that can be applied in the oral cavity are still being continuously researched. When using fluoride topical application on the enamel surface, it was highly recommended that fluoride varnish be used directly after fluoride iontophoresis rather than fluoride iontophoresis only or fluoride varnish by itself. The new method is more effective and does not need repeated application.

• 한국광학회지
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• 제6권4호
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• pp.296-301
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• 1995

광섬유격자와 단방향성 광섬유 loop mirror를 이용하여 단일모드로 발진하는 erbium첨가 광섬유레이저를 구성하였다. 이득매질인 erbium첨가 광섬유를 단방향성 loop내에 둠으로써 레이저광이 이득매질내에서 진행파를 이루도록 하고 loop 밖에서 반사 선폭이 0.2nm인 광섬유격자로 파장선택적 귀환시켜 주는 방식으로 공진기를 구성하였다. 수동형 광섬유 링공진기 형태의 광스펙트럼 분석기를 별도로 구성하여 광섬유레이저의 모드 스펙트럼을 관찰한 결과, 외부 온도변화로 인한 분 단위의 모드 튐을 제외하고는 대부분의 시간에 안정적인 단일모드 및 단일편광 상태의 특성을 나타냄을 확인할 수 있었다.

• 대한구순구개열학회지
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• 제10권1호
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• pp.17-22
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• 2007

The vertebrate upper lip forms from initially freely projecting maxillary, medial nasal, and lateral nasal prominences at the rostral and lateral boundaries of the primitive oral cavity. These facial prominences arise during early embryogenesis from ventrally migrating neural crest cells in combination with the head ectoderm and mesoderm and undergo directed growth and expansion around the nasal pits to actively fuse with each other. Initial fusion is between lateral and medial nasal processes and is followed by fusion between maxillary and medial nasal processes. Fusion between these prominences involves active epithelial filopodial and adhering interactions as well as programmed cell death. Slight defects in growth and patterning of the facial mesenchyme or epithelial fusion result in cleft lip with or without cleft palate, the most common and disfiguring craniofacial birth defect. This review will summarize the current understanding of the basic morphogenetic processes and molecular mechanisms underlying upper lip development.

• Journal of Chest Surgery
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• 제22권5호
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• pp.800-805
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• 1989

The roentgenologic appearance of carcinoma of the lung may vary considerably from case to case. And when it forms cavitary lesion, it is frequently confused with benign lesions and treated conservatively. Twenty-seven patients with cavitary bronchogenic carcinoma were treated in our St. Marys Hospital during the period 1984-1989. There were 24 males and 3 females. They ranged in age from 43 to 76 years. Symptoms of cough, blood-streaked sputum or pleuritic chest pain were present in all patients one month to 6 months before hospital admission and 7 patients among them were delayed in recognition of the malignancy from z month to 3 months. Of 27 malignancies with cavity, 22[81.5 %] were squamous cell ca., 3[11.1%] were large cell ca., and 2[7.4%] were adenoca. And of 22 squamous cell carcinomas, 5 were well differentiated, 13 were moderately and 4 were poorly. All lobes except Rt. middle lobe were involved [RUL 2 cases, RLL 13 cases, LUL 3 cases and LLL 9 cases]. We explored 16 patients and performed 7 lobectomy, 4 bi-lobectomy, 2 pneumonectomy and 3 08zC. Post-operative follow-up examination of the resected 13 patients indicated one and two year survival rates of 69.1 %[9/13 cases] and 37.5%[3/8 cases] respectively, and now 6 survivors whose post-operative periods were from 4 months to 37 months.

• 소성∙가공
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• 제7권6호
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• pp.554-561
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• 1998

This paper describes a research work of developing a computer-aided design of lead frame semicon-ductor with piercing operation which is very precise for progressive working. An approach to the sys-tem is based on to knowledge-based rules. Knowledge for the system is formulated from plasticity theories experimental results and the empirical knowledge of field experts. This system has been writ-ten using AutoLISP to AutoCAD on a personal computer and is composed of three main modules which are input and shape treatment production feasibility check and strip-layout module. Based on the knowledge-based rules the system is designed by considering several factors such as material and thickness of product complexities of blank geometry and punch profile, and availability of press. Also strip-layout drawing generated by piercing operation according to punch profiles considered V-notch dimple. pad chamfer spank cavity punch camber and cross bow of lead frame is displayed in graphic forms. This system can be used by a novice who may not have any knowledge of tool design and will invrease efficiencies to the designer in this field.

• International Journal of Naval Architecture and Ocean Engineering
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• 제4권2호
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• pp.123-131
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• 2012

When the object is traveling in the water at tremendously high speeds, the cavity forms and grows up at a fore part of the object called cavitator, and the object is eventually enveloped by vaporized water, supercavitation. As a result, the only part of the object in direct contact with the water is the cavitator, so skin-friction drag is significantly reduced. This is why recently supercavitating objects have been interested in many applicable fields. In this study we are focused out attention on supercavitating flows around various shapes of two and three dimensional cavitators. First, general features of supercavitation are examined by analyzing results obtained by the previously developed numerical method. Second, experimental observations are carried out at a cavitation tunnel at the Chungnam National University (CNU CT), and supercavity dimensions are scrutinized.

• 대한소아치과학회지
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• 제37권4호
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• pp.488-496
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• 2010

치외치는 교합면에 법랑질이 원추형으로 돌출되어 결절을 형성한 치아로서, 치아발육 중 법랑기의 내측법랑상피가 외부로 과증식되거나 치수 간엽조직이 국소적으로 과증식되어 나타난다. 교합력이나 저작에 의해 파절 또는 마모되기 쉬우며 따라서 이로 인하여 치수노출에 의한 감염이 야기될 수 있다. 상악 전치부 설면에도 원추형으로 돌출된 결절이 관찰되기도 하는데 이를 탈론 교두(talon cusp)라 한다. 치내치는 치아 발육 중 설측의 법랑상피가 일부 함입되어 설측에 깊은 소와가 형성된 형태로서 크기나 전체적인 모양은 정상이다. 방사선 사진상에서 치경부의 법랑질 일부가 함입되어 함입강을 형성하고 그 기저부는 치수에 가까이 위치하고 있어 치수와 개통되어 있을 가능성도 있다. 탈론 교두(talon cusp)와 치내치는 비교적 흔한 형태 이상이지만, 한 치아에 동시에 발생하는 경우는 매우 드물다. 이러한 환자에서 탈론 교두(talon cusp)가 교합력이나 저작에 의해 파절되거나, 교두 사이 열구가 우식에 이환되어 치수치료가 시행 될 때, 치내치의 복잡한 근관 형태로 인해 많은 어려움이 있다. 따라서 교합조정, 치면열구전색술 등의 예방적 처치와 주기적인 검진이 필요하고, 치수치료시 정확한 방사선학적 진단을 통한 치내치의 근관 형태 파악이 필요하다. 조선대학교 치과병원 소아치과에 내원한 10세 남아(하악 좌측 중절치)와 8세 여아(상악 우측 중절치) 그리고 7세 남아(상악 우측 중절치)에서 치내치를 동반한 탈론 교두(talon cusp)가 관찰되어 본 증례를 보고하고자 한다. 9세 남아와 8세 여아는 치수 병변으로 인해 치수 치료 중이고, 7세 남아는 병적 소견 없이 교합조정 후 관찰 중이다.

• 한국광물학회지
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• 제15권3호
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• pp.147-159
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• 2002

한 구릉상에 자연적으로 노출된 지표면을 따라 대략 50 cm 이내의 두께를 이루며 분포한다. 풍화된 벤토나이트에는 몬모릴로나이트 외에 7 $\AA$형 할로이사이트가 수반되고 그 하부에 인접하는 벤토나이트에 비해서 상대적으로 원암의 광물성분이 거의 잔류되지 않는 점토광물 위주의 광물조성을 보인다. 전자현미경 하에서 몬모릴로나이트와 할로이사이트는 서로 혼재되기보다는 따로 구획되어 분리된 상태로 산출되는 경향이 있다. 몬모릴로나이트의 엽편상 결정형의 테두리가 다소 변형되어 무딘 편상 결정형의 양상을 보인다. 할로이사이트는 0.3 $\mu$m 내외의 폭과 2 $\mu$m 이내의 길이를 갖는 침상 내지 관상의 결정형을 이루고 흔히 다발형태의 집합체를 형성한다. 전자현미경 관찰을 통한 이들의 미시적 조직 및 산출 관계에 대한 해석에 의하면, 몬모릴로나이트에서 할로이사이트로의 상전이는 혼합층상 구조형 (M/H)과 같은 이들의 중간형 점토광물상을 거치지 않는 형식으로 이루어진 것으로 판단된다. 또한 몬모릴로나이트로부터 할로이사이트로의 변질반응은 산화조건에서 용해 및 침전 반응형식으로 진행되었던 것으로 해석된다 이 풍화변질 과정에서 $SiO_2$를 비롯하여 Na, K 및 Ca과 같은 화학성분들이 심하게 용탈되어 많은 용해공극이 형성되었고, 상대적으로 잔류.농집된 $A1_2$$O_3$와 Fe에 의해서 할로이사이트의 생성여건이 조성되었던 것으로 해석된다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권4호
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• pp.355-362
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• 2000

Neoplastic growth is characterized by alterations of oncogenes and antioncogenes. The interaction between activated oncogenes and functional deletion of antioncogene appears to be the driving force directing normal cells to uncontrolled growth resulting in tumor. In addition to those genes mentioned, other genes controlling the entry of cells into the cell cycle have recently been implicated in cancer development. The overexpression of the cyclin D1 gene, which has been mapped to 11q13, either by gene rearrangement or amplification has been noted in various malignant tumors. The product of the cyclin D1 gene forms a complex with cyclin-dependent protein kinases(CDK4) that governs a key transition in the cell cycle. The relationships between the overexpression of cyclin D1 assessed by immunihistochemistry and the amplification of the cyclin D1 gene by differential polymerase chain reaction(DPCR) using primers for dopamin D2 receptor gene in 13 cases of squamous cell carcinomas of the oral cavity have been studied. The semiquantitative assay of cyclin D1 amplification has been made by cyclin D1/dopamin D2 receptor(CD/DR) ratio. The results were as follows; 1. In the normal tissue and the tumor, the CD/DR ratios were 0.82 and 1.36 respectively. This implicates 1.65-fold amplification of cyclin D1 gene in tumor compared to that in normal tissue. 2. The tumor tissue which showed overexpression of cyclin D1 by immunohistochemistry revealed 2-fold amplification of cyclin D1 compared to the normal tissue. 3. The tumor tissue which showed mild expression of cyclin D1 by immunihistochemistry revealed 1.7-fold amplification of cyclin D compared to the normal tissue. 4. The cyclin D1 was overexpressed in the tumor tissue at the rate of 38%. Above results suggest that cyclin D1 has close correlation with the development of carcinoma in the oral cavity. But further studies were needed to elucidate the carcinogeneic mechanisms by comparative studies among cyclin D1, pRb and p53.

• Asian Pacific Journal of Cancer Prevention
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• 제15권18호
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• pp.7891-7895
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• 2014

Background: Tobacco products continue to be used in large quantities in India despite the mandatory inclusion of pictorial health warnings (PHWs) on all tobacco packaging. The circumstances as to how people could continue the use of tobacco to the point of developing head and neck cancer despite enhanced awareness about the ill effects of tobacco is the main focus of this study. Materials and Methods: This study concerned patients with least 5-years history of tobacco use, having been diagnosed with histopathologically proven malignancies of the hypopharynx, larynx, oropharynx and oral cavity presenting at the Government Medical College-Haldwani, Nainital, India. A total of 183 patients were eligible for inclusion during July 1 2013 - June 30 2014. Of these, 59 patients used smoked tobacco exclusively, 22 patients used smokeless tobacco exclusively, and 102 patients used both forms of tobacco. Among users of smoked forms, 75.2% (n=121) were beedi users, and 24.8% (n=40) were cigarette users. Patients were asked direct questions as to whether they had noticed the presence of PHWs upon tobacco products. The reasons as to why PHWs were not effective in stopping the patients from tobacco use were investigated. Results: Of the 183 patients, 146 reported being aware about the presence of PHWs, and when they were asked reasons as to why they continued tobacco despite being aware of ill-effects, the commonest reason chosen (by 53.4%) was that patients had not regarded themselves as using tobacco heavy enough to cause cancer. Among the 36 patients who reported as being oblivious to the presence of PHWs on tobacco products, 63.9% reported that the products they used never displayed any PHWs, and 36.1% reported never having paid attention to the packaging. The awareness about PHWs was higher among cigarette smokers in comparison to beedi smokers (100% vs 76.1%, p=0.0002). Conclusions: Locally produced and marketed tobacco products such as beedis and oral tobacco often fail to display PHWs. The presence of PHWs without doubt enhances awareness about the carcinogenic risks of tobacco. However, enhanced awareness alone may not be enough, and as elucidated by this study, some persons continue to use tobacco to the point of developing malignancies. The need of the hour is the implementation of legal and economic sanctions discouraging the use of tobacco products.