관상동맥 시술 도중 발생한 좌주간부 관상동맥 박리에 대한 스텐트 삽입 치료의 단장기 임상 결과 : acute and long-term results

이세환,이승환,홍명기,김영학,이철환,한기훈,송종민,강덕현,송재관,김재중,박성욱,박승정 대한내과학회 2004 대한내과학회지 Vol.66 No.6

목적 : 심도자 사용 시술과 관련된 좌주간부 관상동맥박리에 대한 적절한 치료는 아직 확실히 정립되지 않은 상태이다. 이에 본 연구는 좌주간부 관상동맥 박리에 대한 스텐트 삽입술의 단장기 임상결과를 후향적으로 분석하였다. 방법 : 좌주간부 관상동맥 박리에 대한 치료로 즉각적인 스텐트 삽입술을 시행하는 것이 안전하고 효과적인 방법임을 가설하였고, 이러한 즉각적인 스텐트 삽입을 시행한 10명의 환자를 대상으로 단장기적 임상경과를 의무기록 고찰과 전화 면담을 통해서 평가하였다. 결과 : 전체 환자 모두 처음부터 좌주간부 관상동맥에 유의한 협착을 가진 환자는 없었으며, 8명의 환자는 심도자의 조작으로 인한 박리가 발생한 경우였고(진단적 혈관 조영술 중에 3명, 유도 도자 조작 중에 5명), 나머지 2명은 다른 병변에 스텐트 삽입시술을 하는 중에 박리가 발생하였다. 이 10명의 환자에서 모두 즉각적인 스텐트 삽입술이 시행되었고, 4명의 환자에서 시술 도중 혈압 저하로 Intra-aortic Ballon Pump (IABP)를 장착하였다. 모든 환자에서 성공적으로 스텐트가 삽입되었고, 병원내 사망은 1명도 없었다. 6개월 추적 관상동맥 조영술은 8명의 환자에서 시행되었다. 혈관 조영상의 재협착(직경 협착 50% 이상)은 8명 모두에게서 관찰되지 않았으며, 퇴원 후 평균 31±25개월의 추적관찰 결과 주요 심장사건은 1건도 발생하지 않았다. 결론 : 비록 대상 환자가 적은 연구였지만 좌주간부 관상동맥 박리에 대한 스텐트 삽입술은 기술적으로 안전하고 빠르게 시행 할 수 있으며, 훌륭한 단장기적인 치료 효과를 보여준다. Background : The optimal treatment of patients with left main coronary artery (LMCA) dissection during catheter-based procedure remains uncertain. We retrospectively analyzed the acute and long-term results of bail-out stenting for LMCA dissection. Methods : In cases with significant LMCA dissection occurring during catheter-based procedure, prompt stent implantation may be safe and associated with favorable clinical outcome. We evaluated the acute and long-term results of bail-out stenting for LMCA dissection occurring during catheter-bases procedure in 1- patients. Results : Initially, there was significant stenosis of LMCA segment in these patients. Catheter-induced dissection occurred in 8 patients (during diagnostic angiography in 3 patients and guiding catheter manipulation in 5 patients). Two patients suffered dissection in the setting of stent deployment in other vessels. Therefore, bail-out stenting LMCA dissection was performed in a total of 10 patients. In 4 patients, hypotension developed and intra-aortic balloon pump was placed during procedure. Stents were successfully deployed in all patients. There was no in-hospital mortality. Six-month angiographic follow-up was performed in 8 patients. Angiographic restenosis(diameter stenosis 50%) was not observed in all patients at follow-up study. During a mean follow-up of 31±25 months after hospital discharge, there was no major adverse cardiac event (death, myocardial infarction, and target lesion revascularization). Conclusion : Bail-out LMCA stenting is technically feasible, and showed good acute and long-term results in a small series of patients.

감속기 기어의 결함진단에 관한 연구

이재현,국재창,이재응 중앙대학교 기술과학연구소 1999 기술과학연구소 논문집 Vol.29 No.-

본 논문에서는 감속기 기어의 결함진단의 문제가 고려되었고, 시간-주파수 영역의 분석 방법인 위이블렛 변환을 결함진단 연구에 이용하였다. 웨이블렛 변환은 시간-주파수 영역에서 좋은 성능을 나타내며 다양한 기본 웨이블렛 함수를 가지고 있고 융통성과 적응력이 있는 변환방법과 해상도를 가지고 있어서, 급격히 변화하는 신호나 비정상 충격신호를 위치신호의 손실없이 잘 분석할 수 있는데, 이는 기어면에서 금속충돌이 일어나고 여거 기어이를 가지고 있는 복잡한 기어 시스템에서 더욱 유용하게 쓰일 수 있다. 또한 웨이블렛이 가진 주요 특성 중 하나인 잡음제거(de-noise) 기능을 사용하여 잡음이 합쳐져 있는 실제 신호를 더욱 효과적으로 분석 할 수 있었다. 실험대상은 두 쌍의 기어 물림이 있는 기어구동계를 사용하였고, 먼저 실험대상인 기어열에서 이론적으로 발생할 수 있는 싸인파들의 합성으로 이루어진 신호를 가지고 시뮬레이션을 실시하였고, 실험장치를 통해 정상상태기어에서의 신호와 기어에 인위적으로 발생시틴 결함에 의해 발생되는 신호를 측정하였으며 이러한 신호를 웨이블렛 변환하는 방법을 통해 결함을 분석하였다. In this paper, the problems of the fault detection of gear trains are considered, and the wavelet transforms are applied to evaluate the performance of detecting the incipient gear damage with real experimental data. The wavelet transform enables one to look at the evolution in time of a signal's frequency content. This property make it very suitable for the detection of transient vibrations generated by developing localized faults in gear trains. Recent applications of the wavelet technique have focused on the use of DWT(Descret Wavelet Transform) coefficients only. In this study, the wavelet denosing is also applied to remove the effect of the noise in the measured vibration signals. The denoised wavelet map is found to display distinctive features in the presence of several kinds of fault in a tooth.

Maximizing Tendency, Purchase Involvement, and Perceptions of Online Bookstores

Lee,Gyudong,Kim,Jang-Hyun,Lee,Jae-Eun 韓國商品學會 2011 商品學硏究 Vol.29 No.6

This paper investigates the effects of the maximizing tendency (i.e., individual differences in pursuing the best option) on purchase involvement and the perceptions of Web sites. By using survey data collected from South Korea and the United States, we analyze the differences in purchase involvement, perceptions of Web sites, and intention to use between satisficers (those with low maximizing tendency) and maximizers (those with high maximizing tendency). In both samples, maximizers show higher purchase involvement than their counterparts. While the perceptions of usefulness and ease of use are significantly different between the two groups in the United States sample, we do not confirm the same pattern in the South Korean sample. We conclude with a discussion of the results and implications.

칼라센서를 이용한 도정도 측정장치 개발

이용국,이대원,윤두현,이재현 성균관대학교 생명과학자원연구소 1996 生命資源科學硏究 Vol.3 No.2

A whiteness measurement system was designed and constructed using the color sensor. The results of its performance were compared with commercial product (Japan, Kett Co.). A degree of rice milling grading is very closely related to the rice color. Measuring and evaluating the small amount of the reflectance depend on the system including color sensor, light source, detector sensitivity, and its geometric shapes. The main components of prototype included lamps as a light source, Amorphous full color sensor with three filters, D. C. power supply, amplifier, A/D converter, and compatible PC computer. Based on the results of this research the following conclusions were made: [1] It was considered suitable that the amorphous full color in the system was used in rice milling degree measurement. [2] The results of comparison between prototype and the Kett whiteness meter were showed that correlation coefficient of prototype was 0.9687 and that of the commercial whiteness meter was 0.9954.

기종성 신우신염 1례

이재욱,구정태,서정일,양창헌,이정호,이동철,이영현,이활,이경섭 동국대학교 경주대학 1997 東國論集 Vol.16 No.1

기종성 신우신염은 주로 당뇨병환자나 폐쇄성 요로질환을 가진 환자에 발생하며 특징적으로 신실질 및 그 주위조직에 가스를 형성하면서 심한 조직괴사를 일으키는 매우 드문 급성 화농성 신감염으로 사망률이 높은 질환이다. 이 질환은 1989년 Kelly와 MacCallum에 의해 처음 보고된 이래 외국문헌에 약 90례 정도가 보고되어 있으며 국내에는 28례가 보고되어 있다. 수액 및 전해질 보충, 인슐린 투여를 통한 적절한 혈당조절 및 항생제 투여등의 내과적 치료와 절개배농 및 신적출술등의 수술적 치료 방법이 있다. 내과적 치료로 가스의 감소가 없는 경우에는 즉각적인 수술적 치료를 시행하여야하므로 이 가스변화에 대한 추적관찰이 중요하다 하겠다. 본 저자들은 당뇨병환자에서 발생한 기종성 신우신염 1례를 내과적 요법을 치험하였기에 문헌고찰과 함께 보고하고자 한다. Emphysematous pyelonephritis is rare, life-threatening infection of the renal parenchyma and perirenal tisseue. This disease is characterized by the production of intrarenal and perirenal gas and is frequently encountered in patients with diabetes mellitus or urinary obstruction. We experienced a case of emphysematouse pyelonephritis in a 62 years old women with poorly controlled diabetes mellitus who had been managed with medical theraphy. So we report this case with a review of the referenced literatures.

봉독약침이 류마티스 관절염 환자의 기능회복 및 삶의 질에 미치는 영향

이상훈,이현종,박상민,김수영,박재경,홍승재,양형인,이재동,최도영,김건식,이두익,이윤호 WHO COLLABORATING CENTRE FOR TRADITIONAL MEDICINE 2003 東西醫學硏究所 論文集 Vol.2003 No.-

Objective: To evaluate the effects of bee venom acupuncture(BVA) on the rehabilitation and quality of life in rheumatoid arthritis(RA) patients Methods: Patients with RA were treated with the BVA therapy twice a week for 3 months. Tender joint counts, swollen joint counts, morning stiffness, Erythrocyte Sedimentation Rate(ESR), C-reactive protein(CRP), patient global assessment, physician global assessment, Korean health assessment questionnaire(KHAQ) were estimated and analyzed before and after BVA therapy. Results: Tender joint counts, swollen joint counts, morning stiffness showed significant decrease after BVA therapy. But, as acute inflammatory reactants, ESR showed no significant difference and CRP showed significant increase after BVA therapy. Patient global assessment physician global assessment, and KHAQ index showed significant improvement after BVA therapy. Conclusions: BVA therapy can improve rehabilitation and health-related quality of life RA patients as well as clinical symptom and signs. Further study is required in more population with large scale including acute inflammatory reaction of BVA therapy.

Light-extraction efficiency control in AlGaN-based deep-ultraviolet flip-chip light-emitting diodes: a comparison to InGaN-based visible flip-chip light-emitting diodes.

Lee, Keon Hwa,Park, Hyun Jung,Kim, Seung Hwan,Asadirad, Mojtaba,Moon, Yong-Tae,Kwak, Joon Seop,Ryou, Jae-Hyun Optical Society of America 2015 Optics express Vol.23 No.16

<P>We study light-extraction efficiency (LEE) of AlGaN-based deep-ultraviolet light-emitting diodes (DUV-LEDs) using flip-chip (FC) devices with varied thickness in remaining sapphire substrate by experimental output power measurement and computational methods using 3-dimensional finite-difference time-domain (3D-FDTD) and Monte Carlo ray-tracing simulations. Light-output power of DUV-FCLEDs compared at a current of 20 mA increases with thicker sapphire, showing higher LEE for an LED with 250-관m-thick sapphire by ~39% than that with 100-관m-thick sapphire. In contrast, LEEs of visible FCLEDs show only marginal improvement with increasing sapphire thickness, that is, ~6% improvement for an LED with 250-관m-thick sapphire. 3D-FDTD simulation reveals a mechanism of enhanced light extraction with various sidewall roughness and thickness in sapphire substrates. Ray tracing simulation examines the light propagation behavior of DUV-FCLED structures. The enhanced output power and higher LEE strongly depends on the sidewall roughness of the sapphire substrate rather than thickness itself. The thickness starts playing a role only when the sapphire sidewalls become rough. The roughened surface of sapphire sidewall during chip-separation process is critical for TM-polarized photons from AlGaN quantum wells to escape in lateral directions before they are absorbed by p-GaN and Au-metal. Furthermore, the ray tracing results show a reasonably good agreement with the experimental result of the LEE.</P>

심혈관계 질환으로 관상질환 집중치료실에 입원한 환자들의 혜후 측정을 위한 APACHEⅢ점수 체계의 임상적 유용성

이공섭,이창선,최현주,홍종서,강지향,김도형,이민영,오인균,김병엽,김상억,김학찬,한승혜,이재용,지영우,안경주 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.8

Low doses of ionizing radiation suppress doxorubicin-induced senescence-like phenotypes by activation of ERK1/2 and suppression of p38 kinase in MCF7 human breast cancer cells

신재식,우상혁,이형찬,홍승우,유두현,홍석일,이왕재,이명석,진영우,안성관,진동훈,박인철 Sookmyung Women's University Research Institute of 2010 여성과 건강 Vol.6 No.1

가토 외고정 모델을 이용한 치밀체형 세라믹스의 골결합능 평가

이재협,이동호,이재학,공현식,안영준,류현승,서준혁,홍국선,김환,장봉순,이춘기 대한정형외과연구학회 2003 대한정형외과연구학회지 Vol.6 No.2