백혈병 세포에서 Multidrug Resistance Gene-1 (mdr1)의 과발현이 ^99m Tc-sestaMIBI 섭취에 미치는 영향

천경아,이재태,이상우,강도영,손상균,이종기,정준기,전수한,이규보 경북대학교 의학연구소 2000 경북대학교병원의학연구소논문집 Vol.4 No.1

Purpose: To determine whether 99mTc-MIBI is recognized by the multidrug resistant P-glycoprotein (Pgp), we have measured quantitatively 99mTc-MIBI uptake in cancer cells. The effects of various Pgp reversing agents on cellular 99mTc-MIBI uptake were also investigated in the presence of multidrug resistance gene-1(mdr1 gene) overexpression. Materisls and Methods: We measured percentage uptake of 99mTc-MIBI at different incubation temperatures both in mdr1 positive and negative cells. The effects of verapamil, cyclosporin, and dipyridamole on cellular uptake of 99mTc-MIBI were also evaluated with or withouts overexpression of mdr1 gene in Cultured murine leukemia L1210 cells. Results: The mdr1 gene expressing cell lines were effectively induced in in vitro with continuous application of low-dose adriamycin or vincristine. Cellular uptake of 99mTc-MIBI was higher in mdr1 negative L 1210 cells than those of mdr1 positive cells, and higher when incubated in 37℃ than 4℃. In the presence of verapamil, cyclosporin or dipyridamole, 99mTc-MIBI uptake was increased upto 604% in mdr1 positive cells. Conclusion: Cellular uptake of 99mTc-MIBI is lower in leukemia cells over-expressing mdr1 gene, and MDR-reversing agents increase cellular uptake. These results suggest that 99mTc-MIBI can be used for characterizing Pgp expression and developing MDR-reversing agents in vitro. (Korean J Nucl Med 1999;33: 152-62)

毛髮 및 爪甲의 성장에 따른 단백성분의 산화

정영도,최기오,양성렬,이춘기,안봉환,이민화 한국노화학회 1992 한국노화학회지 Vol.2 No.1

Fe-Ni-Co 저열팽창성 합금의 고온 변형 특성 및 열간가공에 따른 열팽창 거동 연구

이기안,박종혁,조봉현,남궁정,김문철 대한금속재료학회 2003 대한금속·재료학회지 Vol.41 No.9

The high temperature deformation behavior and the effect of hot compression on the thermal expansion behavior of Fe-29Ni-17Co low thermal expansion Kovar alloy were investigated in the compressive temperature range of 900~1300℃ at the strain rate range of 25~0.01 sec.^(-1). The temperature (T) and strain rate (ε˙) dependence of the flow stress (σ_(0.7)) could be well described by hyperbolic sine law as ε˙= A [sinh(0.0084 σ)^(5.2018)] exp(-330.41/RT). Surface hot cracking and significant voids around grain boundary could be found at low temperature below 1000℃ and low strain rate (0.01 sec.^(-1)). Thermal expansion coefficient α_(30~400) generally increased with increasing compressive temperature. Moreover, α_(30~400) remarkably increased as strain rate decreased at high temperature above 1100℃. However the thermal expansion coefficient α_(30~400) of low compressive temperatures (900℃ and 1000℃) anomalously increased especially at high strain rates. Experimental results indicated that not only α phase appearance but also grain size had definite influence on the thermal expansion behavior with hot deformation. The correlation between microstructure and thermal expansion behavior of Kovar alloy were also discussed.

저열팽창성 Fe-29Ni-17Co 코바 합금의 고온균열 발생과 고온연성에 미치는 S 및 Mn의 영향

이기안,박종혁,조봉현,남궁정,김문철 대한금속재료학회 2003 대한금속·재료학회지 Vol.41 No.12

The effect of S & Mn on the hot ductility of Fe-29Ni-17Co Kovar alloy and the mechanism of high temperature cracking occurrence were investigated. It has been found that the brittle intergranular fracture at high temperature cracking is closely associated with the sulfide along grain boundary. Experimental results showed, especially when the S content was high and the Mn content was free, that small cavities could be nucleated easily on FeS particles along grain boundary and propagated fast at high temperature. The hot ductility of Kovar alloy was drastically increased with the addition of Mn and it was also increased with decreasing S content. SEM and FE-SEM analyses showed that the Mn addition in this alloy could cause ductile intergranular fracture appearance below 1150℃ by the precipitation of MnS. It was proposed from the results that the addition of Mn and optimum S content (below 30 ppm) in Kovar alloy was necessary in order to reduce the hot cracking susceptibility.

치과용 금합금에 대한 금속 프라이머 처리와 열순환 처리가 교정용 브라켓의 전단결합강도에 미치는 영향

이영기,차정열,유형석,황충주 대한치과교정학회 2009 대한치과교정학회지 Vol.39 No.5

치과용 금합금에 교정용 브라켓 접착 시 금속 프라이머와 열순환 처리가 전단결합강도에 미치는 영향을 알아보기 위하여 80개의 치과용 금합금 시편을 샌드블라스팅만 처리한 군과 3종류의 금속 프라이머(Alloy Primer, Metaltite, V-Primer)처리를 시행한 군으로 분류하고, 이를 열순환 처리 시행 여부에 따라 모두 8개 군으로 분류하였다. 만능물성 시험기를 사용하여 브라켓의 전단결합강도를 측정하고, modified ARI (Adhesive Remnant Index) scores를 통해 브라켓 접착면의 파절 양상을 평가하였다. 열순환 처리 미시행 시에는 금속 프라이머의 적용 시 샌드블라스팅만 단독으로 처리한 경우에 비하여 통계적으로 유의성 있는 전단결합강도의 증가가 있었다 (p < 0.05). 열순환 처리를 시행한군에는 금속 프라이머의 처리에 의한 전단결합강도의 변화는 유의한 차이가 없었다 (p > 0.05). 금속 프라이머를 적용한 경우 열순환 처리 미시행 시에는 파절 양상이 브라켓과 접착제 계면에서의 파절 발생 빈도가 높았으나, 열순환 처리 시행 시에는 각 군 간 파절 양상에 유의한 차이가 없었다. 이상의 결과로 금속 프라이머의 적용이 치과용 금합금에 대한 교정용 브라켓 접착 시 초기 접착 강도에서는 유의성 있는 결합력의 증가를 보이나, 열순환 처리 시행 후에는 결합 강도에서는 유의한 차이가 없는 것으로 나타나 금속 프라이머에 의한 결합력 증가가 감소하는 것으로 생각한다. Objective: The aim of this study was to evaluate the effect of metal primers and thermocycling on shear bond strength between the orthodontic bracket and gold alloy. Methods: For this study, 80 specimens made of dental gold alloy were divided into 8 groups based on the combination of metal primers (none, Alloy primer, Metaltite, V-primer) and thermocycling (with and without thermocycling). Shear bond strength testing was performed with a universal testing machine. Bond failure sites were classified by a modified ARI (Adhesive Remnant Index) score. Results: All metal primer treated groups showed a significantly higher shear bond strength than the only sandblasting treated group without thermocycling (p < 0.05). There were no significant differences on shear bond strength in the groups with thermocycling (p > 0.05). Bond failure sites of the metal primer treated group without thermocycling occurred at gold alloy/adhesive interface, whereas there were no differences on bonding failure sites in the groups with thermocycling. Conclusions: These findings suggest that using metal primer on gold alloy enhances the initial bracket bond strength. But, this effect was not shown with thermocycling.

주요우울증에 대한 Milnacipran의 효과 및 안정성 : Fluoxetine과의 비교

이민수,함병주,기백석,김정범,연병길,오강섭,오병훈,이철,정한용,지익성,최병무,백인호 大韓神經精神醫學會 2004 신경정신의학 Vol.43 No.4

Objectives : This 6-week, open label randomized, multicenter study was conducted to evaluate the antidepressant effect and safety of milnacipran and fluoxetine in patients with major depression. Methods : The study was done in patients with major depression diagnosed by DSM-IV who score ≥17 in 17 items Hamilton Rating Scale for Depression (17-item HAM-D) and score ≥25 in Montgomery and Asberg Depression Rating Scale (MADRS). A total of 87 patients were randomized to milnacipran group and fluoxetine group. In cases of the patients taking other antidepressants, 6 weeks of each medication was administered after 7 days of drug excretion period. The evaluation was done using 17 item HAM-D, MADRS, Clinical Global Impression Scale (CGI), and COVI scale after baseline, 1 week, 2 weeks, 4 weeks, and 6 weeks. The side effects that had occurred during the period of our study were put in records by developed/disappeared time, severities, incidences, managements and results. Results : A total of 87 patients were enrolled. 70 (mitnacipran group 39 ; fluoxetine group 31) of them were included for the 6 weeks of research and 17 of them dropped out with in the first week, not due to adverse reactions or deficiency of effects. Total 17 item HAM-D scores, total points of MADRS, and CGI showed significant decrease after 1 week in each treatment group and continued decrease after 2 weeks and 4, 6 weeks. But there was no difference between milnacipran group and fluoxetine group in the antidepressant effect. There were no significant changes in vital sign, CBC, chemistry, and EKG in each treatment group. The commonly reported side elfects of minlacipran were nausea (25.0%), headache (10.7%), vomiting (7.1%),constipation (7.1%), dizziness (7.1%) and those of fluoxetne were GI trouble (11.1%), diarrhea (11.1%), insomnia (11.1%),agitation (5.6%), and dizziness (5.6%). Conclusion : Milnacipran was effective for the improvement of depressive symptoms and was well tolerated and safe in patients with depression.

깨달음과 치유 : "그리스도 요법" 서설

이정기 연세대학교 신과대학 2004 신학논단 Vol.37 No.-

副腎皮質 腺腫을 同伴하는 原發生 Aldosteronism

이기형,전정열 慶熙大學校 1983 論文集 Vol.12 No.-

A 41-year-old-woman with hypertension and hypokalemia underwent adrenalectomy for primary aldosteronism, She was found to have and adenoma in right adrenocortical region on pathologic result. The diagnosis was made by finding low plasma renin activity, which could not be stimulated, and unsuppresable elevated plasma or urin aldosterone. The localization of an adenoma was accomplished by adrenal angioraphy, venography ultrasonogram, and CT. The CT was more helpful to identify the localization of the tumor than other radiologic studies. The patient was recovered completly from hypertension and hypokalemia after operation.

Magnetron sputtering법으로 제조된 Al-1%Cu/Tungsten Nitride 다층 박막

이기선,서수정,김장현,김남철 공주대학교 자원재활용신소재지역협력센터 2000 2차년도 센터 사업 성과집 Vol.2000 No.1

표면 탄성파 디바이스의 전극재료로 사용되는 Al-1%Cu(4000Å)/tungsten nitride 박막을 magnetron sputtering법으로 제조하고 전기저항을 평가한 결과 비정질상의 tungsten nitride 박막을 제조할 수 있었고, 비정질 형성을 위해서 질소비 (R = N2/(Ar+N2))가 10∼40% 정도 필요하였다. Tungsten nitride 박막의 잔류응력은 비정질이 형성되면서 급격히 감소되었다. 이러한 비정질 박막위에 Al-1%Cu합금막이 형성되었다. 다층막은 453K에서 4시간 동안 열처리함으로써 3.6μΩ-cm의 저항를 나타냈는데, 이는 박막내 결정립 성장과 결정 결함의 감소에 기인하였다. As a power durable-electrode in SAW filter. Al-1%Cu/tungsten nitride multi-layer thin film was fabricated by magnetron sputtering process. Tungsten nitride films had the amorphours phase at the nitrogen ratio, R, ranging from 10~40%. The amorphization could be controlled by nitrogen ratio. R = N2/(N2+Ar) as a sputtering process parameter. Residual stress in tungsten nitride abruptly decreased with the formation of amorphous phase. Al-1%Cu thin film was deposited on the amorphous tungsten nitride. After the multi-layed thin film was annealed for 4 hours at 453K, the resistivity decreased as 3.6 μΩ-cm, which was due to grain growth and reduced crystal defects.

객체에 근거한 선호도 제약 중심 스케줄링 언어와 성능향상 기법

이기철,문정모,송성헌 한국경영과학회 1995 經營 科學 Vol.12 No.2

For a complex scheduling system like time table construction, its optimal solution, if exists, is hard to obtain. In this paper, the scheduling environment is reasonably confined as where objects have their own events competing for better slots on boards, and objects have their own board slot preferences and belong to one or more classes of the society which globally constrains them. Here, two phase method is suggested, where the first phase is human-like preference dirven and the second phase is for fine tuning by considering all the factors given. Designed and implemented in our system HI-SCHED are dynamic object switching, temporal-constraint-driven intelligent backtracking, case-based revisions, object-based approach, and so on. Some satisfaction degrees are also defined to measure the usefulness of our method. In addition, look-ahead dynamic object switching is considered, and additional global constraints are introduced and processed. A simple scheme is also used to verify the usefulness of the post processing scheme.