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Comparison between Myocardial Perfusion and Function in Rest State in Coronary Artery Disease - Dipyridamole $^{99m}Tc-MIBI$ SPECT and Rest Gated Blood Pool Scan - (관상동맥질환에서 휴식기의 심근관류 정도와 휴식기 심기능 변화의 비교 - Dipyridamole 부하 $^{99m}Tc-MIBI$ SPECT와 휴식기 Gated Blood Pool Scan -)

  • Choi, Chang-Woon;Lee, Dong-Soo;Kim, Sang-Eun;Bae, Sang-Kyun;Yang, Hyung-In;Chung, June-Key;Lee, Myoung-Mook;Lee, Myung-Chul;Park, Young-Bae;Seo, Jung-Don;Lee, Young-Woo;Koh, Chang-Soon
    • The Korean Journal of Nuclear Medicine
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    • v.26 no.2
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    • pp.265-273
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    • 1992
  • Rest gated blood pool scan (Rest GBP scan) and dipyridamole $^{99m}Tc-MIBI$ SPECT were Performed in 34 patients with or suspected coronary artery disease. Both studies were performed within $2\sim32$ days (mean 8.1 days). A significant correlation was present between left ventricular ejection fraction (r= -0.7356, p<0.001) and peak ejection rate and peak filling rate in rest GBP scan and perfusion defect in MIBI SPECT. And there were acceptable correlations (0.05$26.2{\pm}10.8%$, severe hypokinesia, akinesia or dyskinesia in 16 regions: $78.2{\pm}23.7$, p<0.001). These data indicate there is a significant coupling between the degree of myocardial perfusion and the myocardial functional change in coronary artery disease.

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Comparison of $^{99m}Tc-MIBI$ Myocardial Uptake at Rest with Reinjection and 24-hour after Reinjection Images of $^{201}Tl$ ($^{201}Tl$$^{99m}Tc-MIBI$에 의한 생존심근의 진단 비교 -재분포영상에 고정관류결손을 보인 환자에서 $^{201}Tl$ 재주사법 및 $^{99m}Tc-MIBI$ 휴식기스캔에 의한 심근섭취 비교-)

  • Bom, Hee-Seung;Kim, Ji-Yeul;Park, Joo-Hyung;Ahn, Young-Keun;Jeong, Myung-Ho;Cho, Jeong-Gwan;Park, Jong-Choon;Kang, Jung-Chaee
    • The Korean Journal of Nuclear Medicine
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    • v.26 no.2
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    • pp.274-279
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    • 1992
  • Clinical role of $^{99m}Tc-MIBI$ myocardial scintigraphy in the diagnosis of coronary artery disease (CAD) is now well accepted, however, the role of it in the identification of viable myocardium in patients with chronic CAD has not yet been clarified. To determine the usefulness of rest-injected $^{99m}Tc-MIBI$ scan as a marker of myocardial viability, the regional uptake of this agent at rest was compared with that of $^{201}Tl$ on reinjection and 24 hours after reinjection images. Subject patients were 13 chronic CAD patients who showed irreversible perfusion defect(s) on standard pharmacologic (dipyridamole) stress-redistribution images. Immediately after the redistribution images were obtained, 37 MBq thallium was injected at rest, and images were reacquired at 10 minutes and 24 hours after reinjection. After then 740 MBq $^{99m}Tc-MIBI$ was injected, and 1 hour later rest MIBI myocardial imaging was performed. Five sets of imagestress, redistribution, reinjection, delayed images of thallium, and rest image of MIBI) were then analyzed qualitatively and quantitatively. Left ventricle was arbitrarily divided into 9 segments (apex, basal and apical portions of anterior, septal, inferior, and lateral walls). Seven patients and 30 regions showed a fixed perfusion defect on the stress-redistribution images. Among 30 regions, 15 showed positive uptakes and 6 showed negative uptakes on both $^{201}Tl$ reinjection/delayed images and $^{99m}Tc-MIBI$ rest images. Five regions showed only thallium uptake and were regarded as viable clinically. Of four regions which showed only $^{99m}Tc-MIBI$ uptake, two were regarded as viable, while the other two were regarded as a nonviable scar tissue clinically. In conclusion, $^{201}Tl$ reinjection technique was more reliable in the identification of viable myocardium. However, the role of $^{99m}Tc-MIBI$ in identification of viable myocardium was still remained to be clarified because 2 of 9 regions showed only $^{99m}Tc-MIBI$ uptake and were regarded as viable tissues.

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The Distribution Characteristics of Floating Debris on the Cruising Routes from Cheju Island to Qindao Harbor in the Yellow Sea (한국 제주도와 중국 청도의 항로상에 부유하는 해양폐기물의 분포에 관한 연구)

  • Kim, Min-Suk;Kim, Jong-Hwa;Kim, Sam-Kon
    • Journal of Fisheries and Marine Sciences Education
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    • v.11 no.2
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    • pp.203-215
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    • 1999
  • Floating debris was recorded from a training ship, Kaya, of Pukyong National University with about 12 knots speed at July 19~21, 1999 and July 24~26. The sampled area is the Yellow Sea (YS) connected from Cheju Is. of Korea to Qindao harbor of China, divided into 88 unit segments on survey routes. Debris fabrication materials were categorized with 6 items using the following; man-made or natural wood items, paper and cardboard, nylon netting and rope, styrofoams, vinyl and plastics, floating metal and glass containers. All identified items within a $120{\pm}20m$ wide band were recorded but ignored if beyond this boundary. The results of distribution of floating debris in the area are as follows: 1. The greatest quantities of marine debris discovered during the survey were $184pieces\;per\;km^2$ near Qindao harbor. The next polluted areas, Sohuksan islands, positioned in the eastern part of YS were scattered in about $40pieces/km^2$ or so. 2. Among items, woods, paper and cardboard, vinyl and plastics were found out near Qindao Coast of China. On the other hand, there were many styrofoams, nylon netting and rope near the area of Sohuksan islands in the eastern part of YS. 3. The distribution densities of western part of YS near Qindao are varied with largely range in items and quantities but those of the eastern part, near Sohuksan islands were nearly constant. 4. Styrofoams were composed of 63% among all debris in YS, next paper and cardboard 15%, and wood item, vinyl and plastics each 10%. Therefore, marine debris of YS is revealed that distribution characteristics and composition are very different in each area. These phenomena are concluded that they largely depend on the life styles in land and the utilities of the sea. And of items, styrofoams is dominated by the distribution pattern of YS. Furthermore, surveys are continuously being investigated, and from this it is hoped that a much wider coverage can be achieved, perhaps all sites of the YS and contributed to the finding sources, the stationary area and removal method of debris joined the flow patterns.

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Calculation of Greenhouse Gas and Air Pollutant Emission on Inter-regional Road Network Using ITS Information (지능형교통체계(ITS) 정보를 이용한 지역 간 도로의 온실가스 및 대기오염물질 배출량 산정)

  • Wu, Seung Kook;Kim, Youngkook;Park, Sangjo
    • Journal of Korean Society of Transportation
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    • v.31 no.3
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    • pp.55-64
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    • 2013
  • Conventionally, greenhouse gas (GHG) emissions in the transport sector have been estimated using the fuel consumption (i.e. Tier 1 method). However, the GHG emissions on road networks may not be practically estimated using the Tier 1 method because it is not practical to monitor fuel consumption on a road segment. Further, air pollutant emissions on a road may not be estimated efficiently by the Tier 1 method either due to the diverse characteristics of vehicles, such as travel speed, vehicle type, model year, fuel type, etc. Given these conditions, the goal of this study is to propose a Tier 3 level methodology to calculate $CO_2$ and $NO_X$ emissions on inter-regional roads using the information from ITS infrastructure. The methodology may avoid the under-estimation issue caused by the concavity of emission factor curves because the ITS speed or volume information is aggregated by a short time interval. The proposed methodology was applied to 4 road segments as a case study. The results show that the management of heavy vehicles' speed is important to control the $CO_2$ and $NO_X$ emissions on road networks.

Effects of Electroacupucture on NMDA Receptor-dependent Spinal ERK MAPK Expression in CFA-induced Pain Model (전침에 의한 CFA유발 통증모델의 NMDA 수용체 의존적 ERK MAPK 발현 변화)

  • Kim, Ha-Neui;Kim, Yu-Ri;Jang, Ji-Yeon;Choi, Yung-Hyun;Lee, Yong-Tae;Choi, Byung-Tae
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.24 no.6
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    • pp.983-988
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    • 2010
  • The present study aims to investigate a possible mechanism of electroacupuncture (EA) in the spinal dorsal horn that may underlie N-methyl-D-aspartate (NMDA) receptor-associated extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK) signaling pathways. The hot plate latency of the ipsilateral hindpaw of EA-treated rats was significantly decreased compared with complete Freund's adjuvant (CFA)-injected ones. The expressions of NR1 and NR2B subuint mRNA of NMDA receptor in the whole L4-5 segments are decreased by CFA treatment, but NR2B subunit was significantly recovered by EA treatment. When we detected the expression of ERK, there were no significant difference between normal and CFA-treated rats with EA or NMDA receptor antagonist MK801. But phosphorylated ERK expressions were markedly induced by CFA, but these inductions were significantly modulated by EA treatment. Although hosphorylation of ERK was also arrested by MK801, these inductions of CFA-injected rats was markedly inhibited only by co-treatment with EA and MK801. Phosphorylated cAMP response element-binding protein (CREB), ERK-related transcriptional factor, showed a significant increase in CFA-treated rats and this increase was slightly inhibited by EA and MK801 treatments. But immunoreaction for phosphorylated CREB were significantly increased by CFA treatment in the superficial laminae of the dorsal horn and these inductions were significantly arrested by co-treatment of EA and MK801. Consequently, the hyperalgesia induced by CFA are associated NMDA receptor and EA and MK801 may showed anti-hyperalgesia via same mechanism for inhibition of ERK and CREB phosphorylation in the dorsal horn.

Microtuber Formation from In Vitro Codonopsis lanceolata Plantlets by Sugar (탄소급원처리에 의한 기내 더덕 식물체의 비대근 형성)

  • Kim, Ji-Ah;Moon, Heung-Kyu;Choi, Yong-Eui
    • Journal of Plant Biotechnology
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    • v.40 no.3
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    • pp.147-155
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    • 2013
  • In this experiment, we report for the first time mass propagation by in vitro mircrotuberization of Codonopsis lanceolata. We first examined the effect of cytokinins on multiple shoot induction. 2.0 $mg{\cdot}L^{-1}$ of kinetin not only gave the highest rate of shoot induction (19.1%) but also the elongation of shoot (17.1 mm). Secondly, we investigated the effect of sugars on in vitro microtuberization from nodal segments. The diameter of tuberous roots was enlarged in the half-strength MS medium supplemented with 145.9 mM sucrose. Histological analysis revealed that the number of parenchymatous cell containing starch grains increased in the tuberous roots. In addition, unlike in non-tuberous root, vascular bundles were scattered inner cortex layer. Thirdly, in order to preserve and stimulate the germination, microtubers were stored at $4^{\circ}C$ refrigerator during 9 months and then transplanted to the artificial soils (vermiculrite : peatmoss = 1:1 v/v), resulting that the rates of survival and germination were 75% and 70%, respectively. These results indicated that mass propagation of C. lanceolata was achieved by in vitro microtuber formation, suggesting that this protocol might be applied for not only the propagation of elite clones but also conservation of C. lanceolata germplasm.

A Study on the Estimation of Regional Myocardial Blood Flow in Experimental Canine Model with Coronary Thrombosis using Rb-82 Dynamic Myocardial Positron Emission Tomography (실험 개에서 Rb-82 심근 Dynamic PET 영상을 이용한 국소 심근 혈류 예측의 기본 모델 연구)

  • Kwark, Cheol-Eun;Lee, Dong-Soo;Kang, Keon-Wook;Hwang, Eun-Kyung;Jeong, Jae-Min;Chang, Kee-Hyun;Chung, June-Key;Lee, Myung-Chul;Seo, Joung-Don;Koh, Chang-Soon
    • The Korean Journal of Nuclear Medicine
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    • v.29 no.1
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    • pp.48-53
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    • 1995
  • This study investigates a simple mathematical model for the quantitative estimation of regional myocardial blood flow in experimental canine coronary artery thrombosis using Rb-82 dynamic myocardial positron emission tomography. The coronary thrombosis was induced using the new catheter technique by narrowing the lumen of coronary vessel gradually, which finally led to partial obstruction of coronary artery. Ten Rb-82 dynamic myocardial PET scans were performed sequentially for each experiment using our 5, 10 and 20 second acquisition protocol, respectively, and three regions of interest were drawn on the transaxial slices, one on left ventricular chamber for input function and the other two on normal and decreased perfusion segments for the flow estimation in those regions. Single compartment model has been applied to the measured sets of regional PET data, and the rate constants of influx to myocardial tissue were calculated for regional myocardial flow estimates with the three parameter fits of raw data by the Levenberg-Marquardt method. The results showed that, (1) single compartment model suggested by Kety-Schmidt could be used for the simple estimation of regional myocardial blood flow, (2) the calculated regional myocardial blood flow estimates were dependent on the selection of input function, which reflected partial volume effect and left ventricular wall motion, and (3) mathematically fitted input and tissue time activity curves were more suitable than the direct application of the measured data in terms of convergence.

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Development of relational river data model based on river network for multi-dimensional river information system (다차원 하천정보체계 구축을 위한 하천네트워크 기반 관계형 하천 데이터 모델 개발)

  • Choi, Seungsoo;Kim, Dongsu;You, Hojun
    • Journal of Korea Water Resources Association
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    • v.51 no.4
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    • pp.335-346
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    • 2018
  • A vast amount of riverine spatial dataset have recently become available, which include hydrodynamic and morphological survey data by advanced instrumentations such as ADCP (Acoustic Doppler Current Profiler), transect measurements obtained through building various river basic plans, riverine environmental and ecological data, optical images using UAVs, river facilities like multi-purposed weir and hydrophilic sectors. In this regard, a standardized data model has been subsequently required in order to efficiently store, manage, and share riverine spatial dataset. Given that riverine spatial dataset such as river facility, transect measurement, time-varying observed data should be synthetically managed along specified river network, conventional data model showed a tendency to maintain them individually in a form of separate layer corresponding to each theme, which can miss their spatial relationship, thereby resulting in inefficiency to derive synthetic information. Moreover, the data model had to be significantly modified to ingest newly produced data and hampered efficient searches for specific conditions. To avoid such drawbacks for layer-based data model, this research proposed a relational data model in conjunction with river network which could be a backbone to relate additional spatial dataset such as flowline, river facility, transect measurement and surveyed dataset. The new data model contains flexibility to minimize changes of its structure when it deals with any multi-dimensional river data, and assigned reach code for multiple river segments delineated from a river. To realize the newly developed data model, Seom river was applied, where geographic informations related with national and local rivers are available.

Effects of Explants and Growth Regulators on Direct Somatic Embryogenesis in Liquid Culture of Scrophularia buergeriana (현삼의 액체배양에서 체세포배 형성에 대한 치상조직과 생장조절제의 영향)

  • Song, Ji-Sook;Lim, Wan-Sang;Chae, Young-Am
    • Korean Journal of Medicinal Crop Science
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    • v.6 no.4
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    • pp.294-298
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    • 1998
  • The factors affecting direct somatic embryogenesis from different parts of explant in liquid culture of Scrophularia buergeriana were investigated. Direct somatic embryogenesis was dependent on the explant tissues and stem was the most efficient explant. Rapid shoot development occurred on stem after 3-week culture but roots were not developed yet. Plantlets were not formed through somatic embryogenesis after 3-week culture of petiole. Though direct somatic embryo was not observed from leaf segment culture for 3 weeks, normal plantlets were developed after 8-week culture. BA played the main role for somatic embryogenesis in liquid culture and adding of either IAA or NAA caused rather adverse effects. Culture of stem segments in MS liquid medium with BA at 0.5 mg/ l or 0.1 mg/ l was proved to be the most efficient method for producing plantlets through direct somatic embryos.

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A Study on the Automatic Detection of Railroad Power Lines Using LiDAR Data and RANSAC Algorithm (LiDAR 데이터와 RANSAC 알고리즘을 이용한 철도 전력선 자동탐지에 관한 연구)

  • Jeon, Wang Gyu;Choi, Byoung Gil
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.31 no.4
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    • pp.331-339
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    • 2013
  • LiDAR has been one of the widely used and important technologies for 3D modeling of ground surface and objects because of its ability to provide dense and accurate range measurement. The objective of this research is to develop a method for automatic detection and modeling of railroad power lines using high density LiDAR data and RANSAC algorithms. For detecting railroad power lines, multi-echoes properties of laser data and shape knowledge of railroad power lines were employed. Cuboid analysis for detecting seed line segments, tracking lines, connecting and labeling are the main processes. For modeling railroad power lines, iterative RANSAC and least square adjustment were carried out to estimate the lines parameters. The validation of the result is very challenging due to the difficulties in determining the actual references on the ground surface. Standard deviations of 8cm and 5cm for x-y and z coordinates, respectively are satisfactory outcomes. In case of completeness, the result of visual inspection shows that all the lines are detected and modeled well as compare with the original point clouds. The overall processes are fully automated and the methods manage any state of railroad wires efficiently.