p-Anisaldehyde가 조골세포 분화에 미치는 영향

김경민 ․ 이도원 ․ 김현준 ․ 김아랑 ․ 장원구 대구대학교 산업기술연구소 2018 産業技術硏究 Vol.29 No.2

p-Anisaldehyde is a natural fragrance extracted from Pimpinella anisum L., and used as a preservative. This study examined the effect of p-anisaldehyde on osteoblast differentiation. First, cytotoxicity tests were carried out after examining the concentrations that did not show toxicity to the cells. The expression of osteoblast differentiation marker gene was confirmed by RT-PCR and was not effective in the treatment with p-anisaldehyde alone. However, p-anisaldehyde decreased the expression levels of inhibitor of differentiation-1 (Id1), distalless related homeobox (Dlx5), and runt-related transcription factor 2 (Runx2), which are osteogenic differentiation marker genes, which are increased in osteogenic condition. alkaline phosphatase (ALP) activity was also confirmed by ALP staining that p-anisaldehyde reduced ALP activity. These results show that p-anisaldehyde is effective in reducing osteoblast differentiation.

볼링후 발생한 전골간신경 증후군-증례 보고-

김혜경,이희숙,박준명,정광익,박동식 大韓再活醫學會 1998 Annals of Rehabilitation Medicine Vol.22 No.4

탄소 나노튜브의 전계방출 특성

이경원,김은미,권민철,김용,이재열,박홍준 동아대학교 기초과학연구소 2000 基礎科學硏究論文集 Vol.17 No.1

본 연구에서는 emitter와 collector 사이의 간격과 current density 대 electric field (J-K)특성을 초점으로 카본나노튜브의 전계방출 특성을 조사하였다. 카본 소스로 CH4, 촉매 및 희석가스로서 NH3를 사용하고 HFCVD를 이용하여 실리콘 위에 카본나노튜브를 성장하였다. 나노튜브의 지름이 20-40nm이고 길이는 15㎛이다. I-V곡선에서 onset voltage는 Vons=3.36V/㎛이고, 2.5V/㎛ 의 전기장에서 8mA/cm2이상의 높은 전류밀도 특성을 보였다. Fowler-Nordheim 그래프를 그려서 팁의 특성을 나타내는 β값을 계산하였다. We report the field emission properties of carbon nanotube, focusing on current density versus electric field (J-F) characteristics and the spacing between the emitter and collector. We grow carbon nanotubes on sillicon using hot-fillament chemical vapor deposition, using CH4 gas as the carbon source and NH3 gas as the catalyst and dilution gas. Nanotubes are distributed from 20 to 40nm in diameter and 15㎛ long. Onset field of the field emission is 3.36V/㎛ and the current density is 8mA/cm2 at an electric field of 2.5V/㎛. A Fowler-Nordheim plot was made. Field enhancement factor β is calculated.

상악 후방의 부분 무치악부에 Sintered porous surface implant의 적용에 관한 문헌고찰 및 증례보고

최희준,이광호,이영석,손경준 조선대학교 구강생물학연구소 2002 Oral Biology Research (Oral Biol Res) Vol.26 No.2

Implant therapy based on the principle of osseointegration has seen a remarkable expansion of its application in dentistry in recent years. This article is a consideration of an endosseous dental implant device(Endopcre, Innova) that uses a sintered porous surface geometry to achieve implant fixation by bone ingrowth. Its implant is documented excellent survival rate(97.2% after a mean functional time of 34.6 months) in Partially edentulous maxillae and insignificant crestal bone loss from baseline. The combination of an innovative, minimally invasive, indirect sinus elevation procedure with a porous-surfaced dental implant system may allow the routine treatment of posterior maxillary site in patients who would otherwise require much more sophisticated and expensive reconstructive surgery to receive longer dental implants .

상악 유전치부의 치간공간과 인접면 우식에 관한 조사연구

김진영,이광희,라지영,안소연,정승열,임경욱,반재혁 大韓小兒齒科學會 2009 大韓小兒齒科學會誌 Vol.36 No.3

본 연구는 상악 유전치부의 치간공간과 인접면 우식의 상관관계를 평가해보고자 하였다. 익산에 거주하는 만3-7세의 어린이 555명을 대상으로 하였으며 탐침이 통과하는지 여부로 치간공간이 있음과 없음으로 분류하였고 와동이 형성되었거나 법랑질 표면이 연화되었을 경우 인접면 우식이 존재하는 것으로 판단하였다. 연구 결과 다음과 같은 결론을 얻었다. 1. 상악 유전치부의 치간공간은 영장류 공간이 77.4%, 발육공간이 유측절치와 유중절치 사이에서 54.4%, 양유중절치 사이에서 39.0%로 나타났다. 2. 인접면 우식발생율은 우측유견치가 6.3%, 우측유측절치가 14.7%, 우측유중절치가 33.5%, 좌측유중절치가 33.7%, 좌측유측절치가 16.0%, 좌측유견치가 4.7%로 나타났다. 3. 치간공간의 수가 많을수록 상악 유전치의 우식발생율은 낮아졌으나 그 상관관계(r=0.024)는 미약하였다. 4. 상악 유전치부에 공간이 존재하지 않을 경우 존재할 때 보다 평균 우식발생율이 높았으며, 치간공간이 전혀 존재하지 않는 경우 한 곳이라도 치간공간이 존재하는 경우보다 평균 우식발생율이 2배 이상 높은 것으로 나타났다. The purpose of this study was to assess the relationship between interdental spaces and proximal caries in maxillary anterior primary teeth. 555 children aged 3-7 inhabit in Iksan were divided into two groups, depending on the presence of interdental space which was detected by a dental explorer. They were determined to have proximal caries if cavity was formed or the enamel surface was softened. The results were as follows : 1. Regarding interdental spaces, 77.4% had primate spaces; 54.4% had developmental spaces between central and lateral incisor, and 39.0% between central incisors. 2. Interproximal caries incidences in right primary canine, lateral incisor, and central incisor were 6.3%, 14.7%, and 33.5%, respectively. Also interproximal caries incidences in left primary central incisor, lateral incisor, and canine were 33.7%, 16.0%, and 4.7%, respectively. 3. Children with more interdental spaces had less caries incidence, but the relationship was weak(r=-0.024). 4. The mean caries incidence was higher in absence of interdental space of maxillary primary incisors than in presence of space. The mean caries incidence with no interdental space was twice as high as that with presence of interdental space.

Dietary vitamin B12 requirement of Pacific white shrimp, Litopenaeus vannamei

Nalin Medagoda,Kyeong-Jun Lee1 한국수산과학회 양식분과 2023 한국수산과학회 양식분과 학술대회 Vol.2023 No.6

Filler의 양에 따른 치면열구전색재의 물리적 성질에 관한 연구

김경남,이서영,박경준 大韓齒科器材學會 1991 대한치과재료학회지 Vol.18 No.2

Pit and fissure sealants, widely used in preventive dentistry contains Bis-GMA, and due to least amount of filler or not at all, abrasion resistance, strength, and coefficiency of thermal expansion vary markedly with tooth structure in addition to high polymerization shrinkage. For those reasons, adding filler such as direct filling resin can improve some of the shortcoming mentioned above. However, addition of filler reduces fluidity, therefore resulting in less penetration into pits and fissures and reducing the value of pit and fissure sealants. Therefore, the author investigated an appropriate filler content which enhances the abrasion resistance and other properties while maintaining the flow of pit and fissure sealants, on increasing filler content of both base and catalyst by 0, 1, 2, 3, 4, and 5%(wt%) and of base only by 8.4wt% which is maximum addition in manufacturing processes. Penetration coefficiency, diametral tensile strength, abrasion resistance, water absorption, and solubility tests were tested. As a results, 1. Penetration coefficiency was inversely proportional to filler content. 2. Diametral tensile strength, water absorption, and solubility were not significantly affected by filler content. 3. Abrasion resistance was proportional to filler content. 4. By adding 8.4 wt% of filler to base only, the material with overall filler content of 4.2wt% displayed satisfactory abrasion resistance and fluidity.

연산 증폭기 (TL494) 를 이용한 DC/DC 승압 컨버터 제어 시스템 설계

정구종,이혜연,문경주,정유석,이준영,손영익 明知大學校 産業技術硏究所 2009 産業技術硏究所論文集 Vol.28 No.-

A simple control system using an op Amp (TL494) is presented for a DC/DC boost converter. The DC/DC boost converters have many industrial applications including renewable energy sources and hybrid automobiles. The problem of regulating the output voltage in the presence of load variation has been a research subject of interest for many years. After computer simulations with SimPower system of Matlab Simulink, we have developed the converter system in university laboratory according to the design specifications. Since the chip TL494 has both op Amp and PWM comparator even beginners can easily develop the control system. Experimental results show that the proposed system has some robustness with respect to the load variation.

우심방을 침범한 거대 비호지킨씨 림프종 1예

강상범,진승원,이은경,박용현,최용호,김용주,박준철,김재형,홍순조,최규보,권종범,원용순,박건,이은희 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.4

동합금의 생물학적 친화성에 대한 연구

김경남,박경준,이서영 大韓齒科器材學會 1991 대한치과재료학회지 Vol.18 No.2

The rise in the cost of gold was lead to use base metal alloy instead of using gold alloy which was known to be most biocompatible. But these base metal alloys are too hard and have low biocompatibility compared to gold alloy. Especially, nickel allergy & hypersensitivity came to be a problem, so use of these alloys is needed to take a careful consideration. In addition, copper alloy has been used in dentistry until now because of giving a golden color but it has lower castability and higher solubility in the oral environment compared to gold alloy. Many reports also have been made on the high toxicity of copper alloy, which revealed the inadequate dental uses of copper alloy. Recently, NPG copper alloy (Alba Dent Co., U.S.A.) have been introduced in Korea. This study was done cell toxicity test (Agar overlay test) and tarnish test in artificial saliva for 30 days and in 5% Na₂S solution for 13 days for 3 gold alloys, a Ag-Pd alloy, and NPG copper alloy. The results were as followed; 1. NPG copper alloy indicated zone index 3 and lysis index 5 in agar overlay test, which revealed high toxicity compared to gold or silver alloys. 2. In tarnish test, contrast to a small color change of gold and silver alloys, NPG copper alloy had a striking color change, 1st day in artificial saliva indicated 2 degree, 30th day in artificial saliva indicated 4 degree and in 5% Na₂S solution, extreme color change of 5 degree showed even on the 1st day.