최근 8년간(2001-2008) 서울대학교치과병원 소아치과의 진료현황 및 수익분포 변화에 대한 조사

손유진,현홍근,김영재,김정욱,이상훈,김종철,한세현,장기택 大韓小兒齒科學會 2010 大韓小兒齒科學會誌 Vol.37 No.1

The practice pattern of pediatric dentistry in the university dental hospital has been changing for the last several decades, due to socioeconomic changes, developments in dental materials and increasing number of private pediatric dental clinics. The purpose of this study is to survey the changing patterns of pediatric dental treatment in the university dental hospital and to present the future direction for pediatric dentistry. Patient distribution and practice trends were reviewed based on the OCS (order communication system) records of the department of pediatric dentistry, Seoul National University Dental Hospital from 2001 to 2008. Results were as follows; 1. The number of patients increased up to 2005 and decreased in 2006, and has remained constant up to 2008. 2. The proportion of preventive and orthodontic treatment increased and the proportion of restorative and pulpal treatment decreased. 3. In restorative treatment, amalgam restoration decreased and resin restoration increased. 4. Frequency of sedation decreased in 2006, 2007 and increased in 2008. 5. Frequency of general anesthesia increased up to 2008. 소아치과 전문 지역 의원의 증가, 소아치과에 대한 보호자의 인식 변화, 치의학의 발전, 소아치과 진료 범주의 확대 등에 의해 최근 소아치과의 진료 양상이 크게 변화하고 있다. 이러한 변화 양상을 파악하고 앞으로의 대학병원 소아치과 및 소아치과 전문 지역 의원의 진료분담에 대한 방향성을 제시하고자 본 연구를 시행하였다. 2001년 1월 1일부터 2008년 12월 31일까지 서울대학교치과병원 소아치과에 내원한 모든 초진 및 재진 환자를 대상으로, 서울대학교치과병원 종합의료정보시스템(OCS)을 통하여 1년간의 외래환자집계 및 수가코드별 진료 행위 건수 및 수익 분포를 조사하여 다음과 같은 결과를 얻었다. 1. 내원환자의 수는 2001년부터 2005년까지 대체로 증가하다 2006년에 감소하였으며 그 이후에는 2006년도와 별다른 변화가 없었다. 2. 2001년에는 예방치료가 6.84%, 수복치료가 49.96%, 치수치료가 9.64%, 외과치료가 10.78%, 교정치료가 22.78%를 차지하였으나, 2008년에는 예방치료가 15.40%, 수복치료가 28.97%, 치수치료가 3.28%, 외과치료가 14.83%, 교정치료가 37.52%를 차지하여 수복치료와 치수치료의 비율은 감소하고 예방치료와 교정치료는 증가하였다. 3. 수복치료의 비율에 있어서 아말감과 글라스 아이오노머 수복 및 기성금관수복의 비율은 감소하였고, 레진의 비율은 증가하였다. 4. 진정요법하 치과치료는 2005년까지 증가하다 2006년, 2007년에는 감소하였고, 2008년에 다시 증가하였다. 5. 전신마취하 치과치료는 2001년부터 2008년까지 꾸준히 증가하였다.

Silorane-based 복합레진의 색안정성에 관한 연구

손유진,현홍근,김영재,김정욱,이상훈,김종철,한세현,장기택 大韓小兒齒科學會 2010 大韓小兒齒科學會誌 Vol.37 No.1

본 연구의 목적은 silorane-based 복합레진의 색안정성을 기존의 methacrylate-based 복합레진과 비교하여 평가하는 것이다. Silorane-based 복합레진인 P90(3M ESPE, USA), methacrylate-based 복합레진인 Tetric Ceram(Ivoclar Vivadent, Liechtenstein), Z250, Z350(3M ESPE, USA)을 이용하여 시편을 제작하고, 증류수, 커피, 레드 와인, 카레 용액에 담가 1일, 3일, 7일, 14일, 21일, 28일 후 색 변화를 분광광도계로 측정하고 실험 전후의 색상차이(ΔE*_(ab))값을 산출하여 다음과 같은 결과를 얻었다. 1. 카레 용액 > 레드 와인 > 커피 > 증류수의 순으로 레진 시편의 변색이 크게 나타났다. 2. 네 가지 종류의 레진을 비교하였을 때, Z350 > Z250 > Tetric Ceram > P90의 순으로 변색이 크게 나타났다. 3. 카레 용액의 경우 네 종류의 레진 모두에서 침지 1일 이후 수용도 역치 이상(ΔE*_(a)b>3.3)의 변색이 나타났다. 4. 레드 와인의 경우 Z350, Z250, Tetric Ceram에서 침지 1일 이후, P90에서는 침지 28일 이후에 수용도 역치 이상의 변색이 나타났다. 5. 커피의 경우 Z350에서 침지 1일 이후, Z250에서 침지 3일 이후, Tetric Ceram에서 침지 7일 이후에 수용도 역치 이상의 변색이 나타났으나 P90에서는 침지 28일 이후에도 수용도 역치 이상의 변색이 나타나지 않았다. The objective of this study was to evaluate the color stability of new silorane-based composite resin compared with methacrylate-based composite resins after immersion in 3 staining solutions. One silorane-based composite(Filtek P90) and 3 methacrylate -based composites(Filtek Z250, Filtek Z350, Tetric Ceram) were evaluated. Twenty disk-shaped specimens(10×2mm) of each of 4 composite resins were prepared. The specimens were then divided into 4 groups of 5 specimens each and immersed in 3 staining solutions( coffee, red wine, curry solution) or distilled water(control) for 28-day test period. Color of the specimens was measured with a spectrophotometer(Color Eye 7000A) using CIE L*a*b* color space relative to CIE standard illuminant D65 at baseline, 1day, 3days, 7days, 14days, 21days and 28days after staining. The color differences( ΔE*_(ab)) were calculated. The results were obtained as follows ; 1. The mean color changes(ΔE*_(ab)) of the composites were greatest in curry solution, then red wine, coffee and distilled water, in decreasing order. 2. The mean color changes(ΔE*_(ab)) of the composites were greatest in Z350, Z250, Tetric Ceram and P90, in decreasing order.

Evaluation of Hot Deformation and Dynamic Recrystallization Behaviors of Advanced Reduced-Activated Alloy (ARAA)

Sang‑Wook Kim,Hyeon‑Woo Son,Taek‑Kyun Jung,Young‑Bum Chun,Yi‑Hyun Park,Ji‑Woon Lee,Soong‑Keun Hyun 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.4

The hot deformation behavior of advanced reduced-activation alloy (ARAA) was investigated using hot torsion tests. Thefl ow stress decreased as deformation temperature increased and as strain rate decreased. The fl ow behavior demonstratedthe typical dynamic recrystallization (DRX). Based on the constitutive analysis of peak stress, the activation energy for hotdeformation was found to be 330.3 kJ mol −1 . Peak stress was analyzed as a function of the Zener–Hollomon parameter, andcalculated and experimental values were in good agreement. A DRX kinetic model for ARAA was derived with deformationconditions based on the Avrami-type model. It was confi rmed that the volume fraction of dynamically recrystallized grainsincreased as deformation temperature increased and as strain rate decreased. The necklace structure and grain boundarybulging were observed in the deformed microstructure of ARAA. The suggested DRX mechanism for ARAA during hotworking is discontinuous DRX.

Actinobacillus sp. EL-9로부터 생산된 생분해성 폴리에스터의 구조 및 특성

손홍주,이건,김근기,김한수,김용균,이상준 부산대학교 유전공학연구소 1998 분자생물학 연구보 Vol.14 No.-

Actinobacillus sp. EL-9로 부터 추출, 정제된 PHB를 GC, IR 및 NMR로 분석한 후, 그 구조를 확인하였으며, 열적 성질, 점도 및 분자량 등을 검토하였다. Actinobacillus sp. EL-9로부터 추출, 정제된 PHB를 IR,500㎒ ^1H-NMR 및 125㎒ ^13C-NMR 를 이용하여 조성분석을 실시한 결과, 본 공시균이 생산한PHB는3-hydroxybutyric acid 의 homopolymer임을 알 수 있었다. 또한 PHB의melting temperature(T_m)은 169.7℃임을 알 수 있었으며, crystallization trmperature(T_c)는 69.13℃이었다. PHB의 점도는 1.08×10^6(±3,000)이었다. In this study, the composition and characteristic of poly-β-hydroxybutyrate(PHB) biosynthesized by Actinobacillus sp. EL-9 are investigated. PHB produced by Actinobacillus sp. EL-9 was identified as the homopolymer of 3-hydroxybutyric acid(PHB)by infrared spectroscopy and nuclear magnetic resonance spectroscopy analysis. The melting temperature(T_m), and crystallization trmperature(T_c)of PHB was 169.7℃ and 69.13℃, respectively. the viscosity on the basis of Brookfield viscometer was 6.01㎗/g. The viscosity-average molecular weight estimated by Mark-Ho-wink-Sakurada equation was 1.08×10^6(±3,000).

CFT용 초고강도 콘크리트를 이용한 실물대 실험

손영준,송인명,양동일,정근호,정상진,최문식 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

The column for Steel Framed Reinforced Concrete Structure (SFRCS) and the column for Reinforced Concrete Structure (RCS) could be the most common building structure. The increasing of the need for massive space hasaffected the size of building components for supporting the massive structure. However, the changing of components size makes inefficient space of building. Hence, to meet the need for acquiring efficient space comparing the budget and cost the new structure method, Concrete Filled Tube Steel (CFT), was developed. CFT is the structure for which steel tube instead of other materials such as wood for holding concrete is used. The most benefit of this one is to help in reducing the size of the building components and local buckling because of tube steel holding concrete. For this reason, this research will examine the probability of applying CFT on construction sites by using the concrete (800kg/cm2) especially for CFT through the data from the real size mock-up.

연쇄상구균을 실험감염시킨 넙치치어의 병리조직학적 관찰

조성환,류시윤,김현수,박배근,김덕환,손화영,윤원기,신창호 충남대학교 수의과대학 동물의과학연구소 1999 動物醫科學硏究誌 Vol.7 No.-

Pathological observations were examined after abdominal inoculation in 7∼8㎝ sized flounder (Paralichthys olivaceus) with 1X10^7 cfu/㎖ of Streptococcus faecalis. The infected flounder were clinically observed and weighed a fish body at 0, 5, 10, 15, 20, 25, 30 days post inoculation. In infected group, mortality were 70% and feed efficiency were 7.2%. In non-infected group, mortality were 10% and feed efficiency were 18.2%. Macroscopically, the significant lesions were characterized by protrusions and opacity of the eyes and ulcer of the caudal pecuncle. Histopathologically, the lesions were observed a degeneration. necrosis and inflammatory cells in muscle of the caudal peduncle and a degeneration and necrosis of the rod cells and detached retina from the black pigmented layer

고유동 콘크리트용 분리저감형 유동화제의 개발에 관한 기초적 연구

전충근,손성운,김성수,한천구 청주대학교 산업과학연구소 2001 産業科學硏究 Vol.19 No.1

The purpose of this paper is to develope segregation reducing type superplasticizer for high fluidity concrete and to manufacture high fluidity concrete by applying developed segregation reducing type superplasticizer using flowing concrete method in the rane go of 45% of W/C. According to test results, as dosage of superplasticizer increases, it shows that fluidity and bleeding increase, while air content and segregation resistance decrease. It also shows that adding of viscosity agent reduce bleeding and improve segregation resistance. Dosage of AE agent recovers loss of air contents during flowing Procedure. Combination of proper contents of superplasticizer, viscosity agent and AE agent make possible to develope segregation reducing type soperplasticizer According to experimental results, optimal proportion of superplasticizer, viscosity agent and AE agent show to be 1'0.60'0.027 Compressive strength of high fluidity concrete is simihar to comprssive strength of base concrete

시멘트 킬른 더스트를 사용한 콘크리트의 역학적 특성에 관한 연구

전충근,차천수,차완호,손성운,한천구 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1(구조계)

This paper is intended to investigate the properties of fresh and hardened concrete, in which cement and fine aggregate are replaced with cement kiln dust(CKD), for effective using method of CKD, a by-product produced in the process of making cement. According to the results, as the replacing ratio of CKD increases, slump and air content of concrete decreases remarkably due to an increase of viscosity and filling of the pores respectively. As the properties of setting, setting time are shortened with an increase of the replacing ratio of CKD. Compressive strength increases due to the filling effect of the pores in comparison with plain concrete, and compressive strength ratio is high at early age.

한국 재래 우 및 산양 위장관의 somatostatin cell에 대한 면역조직화학적 분포

조성환,김현수,박배근,윤원기,손화영 충남대학교 수의과대학 동물의과학연구소 1995 動物醫科學硏究誌 Vol.3 No.-

The relative frequency and distribution of somatoatatin immunoreactive cells were investigated by the immunohistochemical method in the gastrointestinal tract of the Korean native cattle and goat. The results obtained were as follows: In the Korean native cattle, somatoststin cells were a few in the pyloric and duodenal region and rarely seen in fundic region, jejunum, ileum, cecum, proximal colon, central coil, distal colon and rectum. In the Korean native goat, somatostatin cells were the most numerous in the pyloric region and the next in the fundic region. And they were a few in the duodenum, not detected in the cecum and sparse in the jejunum, ileum, proximal colon, central coil, distal colon and rectum.

개에서 관찰된 모기질세포종의 증례보고

조성환,손화영,김혜성,최종윤,류시윤,박배근,윤원기,홍성혁,김덕환 충남대학교 수의과대학 동물의과학연구소 2002 動物醫科學硏究誌 Vol.10 No.-

Pilomatricoma was histopathologically diagnosed in a 2.5-year-old male Alaskan malamute. The patient was referred to Chungnam National University, Veterinary Medical Teaching Hospital with solitary, firm and well-circumscribed mass at shoulder. Grossly, the mass was dome shaped to tumor like and 10 x 8 x 5㎝ in size. Some lesions had gritty or bony consistency and was chalky when sectioned Histopathologic feature included mumerous clusters of tightly arranged, basaloid cells with evenly distributed chromatin and ghost cells were characterized by a central unstained zone. The ghost cells often become calcified and osseous metaplasia was also present.