재발된 원발성 고환림프종이 동반된 류마티스 관절염 환자에서 Rituximab으로 치료한 1예

박열,박상민,한경택,강지인,이준,김상현 朝鮮大學校 附設 醫學硏究所 2006 The Medical Journal of Chosun University Vol.31 No.3

Several studies have shown that patients with rheumatoid arthritis(RA) have a doubled to tripled increased risk for developing lymphomas compared with the general population, Indeed, primary testicular lymphoma accounts for about 1% of all lymphomas. We present a case of RA with primary testicular lymphoma treated with rituximab. A 67-year-o1d man was admitted due to aggravated polyarthralgia and morning stiffness. hIe was diagnosed testicular diffuse large B cell lymphoma (DLBCL) and done orchidectomy last year. There was no adjuvant chemotherapy nor radiotherapy because of patient's loss. Abdominal computed tomography (CT)scan showed about 6x4cm mass on the left adrenal gland. Malignant lymphoma (DLBCL) was proven by CT guided needle biopsy and he was treated with CHOP (cyclophosphamide, hydroxydaunorubicine, oncovin, prednisone) and rituximab (375㎎/㎡) combination regimen. After two cycle treatment, the clinical symptoms and laboratory data improved.

Analysis of Genetic Diversity of Korean Wheat Cultivars Using Microsatellite DNA Polymorphisms

Park,Yong-Jin,Cho,Gyu-Taek,Ma,Kyung-Ho,Lee,Sok-Young,Lee,Jung-Ro,Kim,Young-Chang,Cho,Eun-Gi,Kim Chang-Yung,Nam,Jung-Hyun,Rao,V,Ramanatha,Kang,Hee-Kyoung 한국자원식물학회 2004 Plant Resources Vol.7 No.2

Genetic background and phylogenetic relationships among 20 Korean wheat cultivars were assessed using microsatellites after amplifying with 13 SSR primer pairs. Average allele number per primer pair was 3.36. Genetic similarities for every pair of cultivars ranged from 0.42 to 0.97, with 0.69 of overall average. Korean cultivars were divided into two major groups based on microsatellite DNA polymorphisms. Group I consisted of relatively old cultivars developed until 1970s, and group II contained the recent cultivars developed during 1980s and 1990s. Amongst old elite cultivars/lines, ‘Yukseung 3’, ‘Norin 12’ and ‘Norin 72’ contributed most to the genetic background of cultivars belonging to group I, and ‘Norin 4’, ‘Norin 12’, ‘Norin 43’ and ‘Norin 72’ to group II, respectively. The phylogenetic relationship of Korean wheat cultivars was in accordance with the genealogical data of each cultivar. The genetic background of each cultivar was assessed from the point of breeding and germplasm management such as variety identification and duplicated accessions for assisting in developing a system for the registration of new variety based on the molecular characterization in future.

치과 재료용 NiTi 합금의 특성에 대한 Ag 첨가의 영향

오근택,박기호,심형민,황충주,김경남 大韓齒科器材學會 2001 대한치과재료학회지 Vol.28 No.4

Equiatomic and near-equiatomic nickel-titanium alloys have shape memory effect and superelasticity. However nickel-titanium alloys are extremely sensitive to the precise nickel-titanium ratio and alloying additions. There are many reports on the alloying additions such as Fe, Al, Cr, Co, V, Pt, Pd, Zr, Hf, Nb and Cu. The purpose of this study was to investigate the effect of silver addition to nickel-titanium alloy for dental and medical application.Arc melting process was used to fabricate nickel-titanium alloys. The casts were heat-treated in a vacuum furnace at 950℃ for 72 hours to homogenize their composition. Subsequently, they were hot-rolled at 950℃ to obtain the plate samples and annealed in a vacuum furnace at 950℃. To investigate the properties of nickel-titanium alloys, phases, transformation temperature, compositions, corrosion resistance and hardness were evaluated using X-ray diffractometer, differential scanning calorimeter, energy dispersive spectroscopy or atomic absorption spectroscopy, potentiostat and micro-vickers hardness tester, respectively. NiTiAg alloys showed the low silver recovery rate for the cast due to its low evaporation temperature, and showed low silver solubility to NiTi alloy. Silver addition to NiTi alloy increased transition temperature range (TTR) above 100℃ and stabilized martensitic phase(monoclinic structure) at room temperature because Ms temperature was above room temperature. Martensitic and austenitic phase existed in x-ray diffraction pattern of solution annealed NiTiAg alloys. The Silver addition is considered to improve corrosion resistance and change largely the mechanical properties depending upon the amount of alloying addition and types of addition elements.

폐 FRP/Urethane Foam 충진 혼성복합재의 제조 및 기계적 물성에 관한 연구

황택성,신경섭,박진원 공주대학교 자원재활용신소재지역협력센터 2000 2차년도 센터 사업 성과집 Vol.2000 No.1

욕조 생산시 발생하는 폐 FRP와 냉장고 등 가전품과 폐단열재로부터 발생하는 폐우레탄폼을 흡음 및 경량판재로 재활용하기 위하여 불포화 폴리에스테르 매트릭스 수지에 보강하여 복합재를 제조하였다. 또한 충진재의 함량의 변화가 복합재의 기계적 물성에 미치는 영향과 기지와 보강재간의 계면현상을 관찰하였다. 충진제의 함량이 70 wt%인 복합재의 인장강도는 82.34MPa로 가장 우수하였으며, 인장탄성율은 보강재의 함량이 증가함에 따라 감소하였다. 또한 굴곡강도와 굴곡탄성율은 폐FRP의 함량이 70wt% 충진된 복합재가 가장 우수하였으며, 그 값은 각각 72.5, 958.4MPa이었다. SEM 관찰 결과 70 wt% 충진된 충진제 매트릭스 수지의 계면에서 pull out 현상이 확인되지 않았으며 균열도 발생하지 않았고, 매트릭스 수지내에 충진된 폐 FRP/우레탄폼 충진제가 잘 분산되어 있음을 확인할 수 있었다. The waste FRP oocured in the fabrication of SMC (sheet molding campound) bathtubs and the waste polyurethane foam occured in electronic manufacture and waste insulator were applied as a soundproof and light weight pannel in the waste FRP unsaturated polyester matrix resin composites to recycle. The effect of filler contents of the mechanical properties and interfacial phenomena of the filler and matrix on the composites was evaluated. The tensile strength of composites reached its maximum value of 82.34 MPa when the filler content was 70 wt%, and the more content of reinforcement is increased, the more tensile modulus was decreased. The flexural strength and modulus of csomposites, reinforced 70 wt% with filler content, were dominant compared to the other samples to 72.5 Mpa, 958.4 MPa respectively. When composite of reinforced 70 wt% with filler content, it was confirmed that pull out phenomena and cracks did not occur in the interface of reinforcement and matrix resin through the SEM observation. Also, waste FRP and urethane foam were dispersed well into matrix resin as filler.

알루미늄 튜브 하이드로포밍에서의 예비 굽힘 공정의 효과에 관한 연구

임희택,박경창,김형종,김헌영 江原大學校 産業技術硏究所 2004 産業技術硏究 Vol.24 No.B

Recently social demands of fuel economy and environmental regulations require the development of lightweight components and new manufacturing technologies. The aluminum tube hydroforming is a manufacturing process which can provide lightweight components as automotive parts. In this paper, the hydroformability of aluminium tube in different condition of bending process is presented. An investigation has been conducted on how to control the deformed shape and its effect on thinning distribution after hydroforming by using finite element simulation. Finite element simulation of tube hydroforming for automotive trailing arm is carried out to explore the effect of 2-dimensional and 3-dimensional bending.

교정학적 적용을 위한 초내식성 스테인리스강의 특성

오근택,김금진,황충주,박용수,김경남 大韓齒科器材學會 2001 대한치과재료학회지 Vol.28 No.3

Various kinds of orthodontic appliances have been developed for ideal tooth movement during orthodontic treatment. The orthodontic appliances made of metals are bands, arch wires, brackets and miniscrews as orthodontic anchorage. Generally, these appliances are made of stainless steel, pure titanium, Ni-Ti and TMA with the proper biocompatibility. However, localized corrosion of these materials can frequently occur in the particular environment. Super stainless steels, recently developed, have good corrosion resistance to reduce metal ion release induced by many kinds of corrosion. Recently, it has been reported that nickel ion release from orthodontic appliances affect the prevalence of nickel sensitization; however, there has been some controversy about nickel hypersensitivity to orthodontic appliances containing nickel. The purpose of this study was to evaluate and compare the microhardness, nickel ion release, corrosion resistance and cytotoxicity of 4 types of super stainless steels and 316L stainless steel as the control group according to nickel contents, and to determine the acceptability as the new material for various kinds of orthodontic appliances. All super stainless steels showed higher microhardness than 316L stainless steel, SR-3Mo showed especially the highest microhardness. In anodic polarization test, corrosion resistance was high in order of SR-50A, SFSS, SR-6DX, 316L stainless steel, SR-3Mo. There was no increase in nickel ion release from SR-50A, SR-6DX, 316L stainless steel with immersion time in artificial saliva; whereas there was some increase from SFSS and SR-3Mo with immersion time. All super stainless steels showed very low cytotoxicity regardless of nickel contents although SR-3Mo showed relatively higher cytotoxicity than the others. It is concluded that SR-50A among super stainless steels has the highest corrosion resistance and biocompatibility. It is undesirable to consider the alloys with high nickel content to release lots of nickel ion.

골내 고정 장치용 초내식성 오스테나이트 및 듀플렉스 스테인리스강 가공재의 특성

오근택,강국진,박용수,김경남 大韓齒科器材學會 2003 대한치과재료학회지 Vol.30 No.3

Nickel is one of the most common causes of allergic contact dermatitis and hypersensitivity. In case of stainless steel as biomaterials, the higher the corrosion resistance and the lower the nickel content, the better it is or the human body. However, because nickel plays an essential role in the stabilization of the austenitic phase and the corrosion resistance of stainless steel, it is difficult to remove the nickel from the constituents of stainless steels completely. Therefore, the purpose of this study was to investigate corrosion resistance, cytotoxicity, and mechanical property of super stainless steels, which had high corrosion resistance by synergistic effect of Mo(or W) and N, with respect to nickel content and to evaluate their potential for orthodontic applications. Super austenitic stainless steel(SR-50A) had high nickel content of 22% and super duplex stainless steels nickel contents of 6~10%. Super austenitic and duplex stainless steels had nitrogen contents of above 0.2%. Also, these steels had high Mo or W contents which were able to increase the localized corrosion resistance. In terms of hardness, super stainless steels, which had Vickers hardness values of 374~400 Hv in cold-rolled state and 186~285 Hv in annealed state, exhibited higher values than 316L S. S.. Duplex stainless steels exhibited higher mechanical properties than austenitic stainless steels. In terms of corrosion resistance, super stainless steels exhibited lower passive current density(2.3~3.8 ㎂/cm^2) than pure Ti(6.6㎂/cm^2) in the body-simulated solution and similar potentiodynamic polarization behaviors. Pitting corrosion occurred in 316L S. S. but not in the others. Thus these steels were considered to have high corrosion resistance in the human body. In terms of cytotoxicity, SR-5OA and SAF2507 exhibited none cytotoxicity and the others slight. This results indicated that the cytotoxicity of alloys containing nickel had no relation with nickel content because SR-5OA with the highest nickel content exhibited none cytetoxicity In conclusion, it is considered that super stainless steels with high corrosion resistance and good biocompatibility can be used for orthodontic applications because of the enhanced passive film by high addition of Mo, W, N, etc.

초내식성 스테인리스강 선재와 브라켓의 내식성 및 금속 이온 용출 특성

오근택,정경진,황충주,박용수,김경남 大韓齒科器材學會 2001 대한치과재료학회지 Vol.28 No.4

Metallic orthodontic appliances are known to release metal ions in an oral cavity. It is not advisable that toxic corrosion products derived from the appliances is absorbed into the body. Metal ions release from orthodontic appliances is known to have large effects on the result of orthodontic treatment and systemic health. Metal bracket and wire were made of super stainless steel(S32050) with high corrosion resistance. The corrosion resistance and ion release property of S32050 and conventionally used appliances were examined. Four types of wire were ligated in either super stainless steel(SB) or Tomy bracket(TB) with O-ring, and then each group was immersed in an artificial saliva at 37℃ for 12 weeks. Amount of released metal ions was measured with immersion time by graphite furnace atomic absorption spectroscopy and surface morphology was investigated. S32050 showed the low passive current density of about 1 μA/㎠ and the stable passive region to a high potential in artificial saliva. S32050 appliances did hardly release nickel ions in artificial saliva. S32050 wire(SRW) and NiTi wire(NW) didn't show significant difference of Ni ion release with immersion time, meanwhile, Remanium wire(RW) showed significant difference in 12 weeks. Ni ion releasce from the brackets didn't show any significant difference with immersion time and between SB and TB. Amounts of Ni ion released from TB-SRW showed significant difference in 12 weeks, those from TB-RW showed significant difference from 4 weeks later and highest release among all groupsin12weeks. TB-NW released little Ni ion for all immersion time and showed significant difference from 4 weeks later, TB-TW(TMA wire) showed significant difference in 12 weks. SB-SRW didn't show any significant difference and SB-RW signigicant difference in 12 weeks,but lower compared with TB group. SB-NW and SB-TW didn't show any significant difference. Corrosion products didn't be observed in mostly groups during the immersion time, except that in TB-RW, they were observed on the bracket surface between O-ring and wire from 8 weeks later. Super stainless steel wire had good corrosion resistance compared with stainless steel wire, and it is believed that it can be used as orthodontic material for bracket and wire.

인터넷 메타데이타 검색 및 관리 시스템의 설계 및 구현

이원석,박경용,양영종,정효택,김순용,이규철 한국문헌정보학회 1997 한국문헌정보학회지 Vol.31 No.2

인터넷은 디지탈 형태의 다양한 정보를 신속하게 전달한다는 점에서 매우 각광을 받고 있다. 그러나, 대량의 인터넷 정보 중에서 자신이 원하는 정보 자원을 정확하게 많이 얻어 낼 수 있는 방법의 제공은 매우 어려운 문제이다. 본 논문에서는 인터넷 정보 자원의 메타데이타를 관리하기 위해 SeriCore라는 SGML 형식의 메타데이타 DTD(Document Type Definition)를 정의하고, 이들 메타데이타를 효율적으로 저장하고 검색, 관리할 수 있는 시스템을 설계, 구현하였다 The Internet has gained popularity because ot provides various information in digital format. However, it is very difficult to provide methods which make it possible to search adequate information resource from bulk of Internet information. In this paper, we define a SGML metadata DTD, named SeriCore, and design and implement a metadata retrieval and management system which can store, retrieve and manage the Internet metadata efficiently

연소에 의한 엔진 진동 특성에 관한 연구

장석영,박경석,오택열,백영남 慶熙大學校 1993 論文集 Vol.22 No.-

Generally, a knock sensor for a high power engine detects cylinder wall vibration and estimates pressure vibration in the combustion chamber. In this study, so combustion pressure detected by pressure tranducer and cylinder wall vibration detected by an accelation sensor are estimated and the difference of those two signals are anlayzed. These two signals are analysed by frequency analysis method and compared with theorical knocking mode in the combustion chamber of the spark ignition engine. Design parameters of the knock sensor are determined by these analysed data.