• 제목/요약/키워드: ROIs

검색결과 168건 처리시간 0.022초

넙치, Paralichthys olivaceus 병어에서 분리된 Streptococcus parauberis의 면역 저항 특성 (Immunomodulatory characteristics of Streptococcus parauberis isolated from infected olive flounder, Paralichthys olivaceus)

  • 황성돈;우승호;김수현;하수진;정영은;박수일
    • 한국어병학회지
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    • 제21권3호
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    • pp.157-166
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    • 2008
  • Streptococcal diseases are known as serious problems in fresh water and marine fish culture industry worldwide. Recently, the importance of the infection of Streptococcus parauberis has been increased among the streptococcicosis since severe outbreaks in cultured olive flounder (Paralichthys olivaceus) were recorded in Korea. The aims of the present study were to investigate immunomodulatory differences between S. parauberis and S. iniae. In this study, S. parauberis isolated from diseased olive flounder was investigated on the characteristics of morphological and immune responses. Immune response of the fish to the pathogen was characterized by bactericidal activity in the serum, phagocytic activity and reactive oxygen intermediaters (ROIs) production of olive flounder. The capsules of both bacteria, S. parauberis and S. iniae seem to be associated with the ability to resist killing activity of normal sera. Also, capsulated strains could survive in the phagocytes and induce to lower ROIs production.

한국형 디지털 마모그래피에서 SVM을 이용한 계층적 미세석회화 검출 방법 (A Hierarchical Microcalcification Detection Algorithm Using SVM in Korean Digital Mammography)

  • 권주원;강호경;노용만;김성민
    • 대한의용생체공학회:의공학회지
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    • 제27권5호
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    • pp.291-299
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    • 2006
  • A Computer-Aided Diagnosis system has been examined to reduce the effort of radiologist. In this paper, we propose the algorithm using Support Vector Machine(SVM) classifier to discriminate whether microcalcifications are malignant or benign tumors. The proposed method to detect microcalcifications is composed of two detection steps each of which uses SVM classifier. The coarse detection step finds out pixels considered high contrasts comparing with neighboring pixels. Then, Region of Interest(ROI) is generated based on microcalcification characteristics. The fine detection step determines whether the found ROIs are microcalcifications or not by merging potential regions using obtained ROIs and SVM classifier. The proposed method is specified on Korean mammogram database. The experimental result of the proposed algorithm presents robustness in detecting microcalcifications than the previous method using Artificial Neural Network as classifier even when using small training data.

An Assessment of the Usefulness of Time of Flight in Magnetic Resonance Angiography Covering the Aortic Arch

  • Yoo, Yeong-Jun;Choi, Sung-Hyun;Dong, Kyung-Rae;Ji, Yun-Sang;Choi, Ji-Won;Ryu, Jae-Kwang
    • 방사선산업학회지
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    • 제12권4호
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    • pp.325-332
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    • 2018
  • Carotid angiography covering the aortic arch includes contrast-enhanced magnetic resonance angiography (CEA), which is applied to a large region and usually employs contrast media. However, the use of contrast media can be dangerous in infants, pregnant women, and patients with chronic renal failure (CRF). Follow-up patients informed of a lesion may also want to avoid constant exposure to contrast media. We aimed to apply time-of-flight (TOF) angiography to a large region and compare its usefulness with that of CEA. Ten patients (mean age, 58 years; range, 45~75 years) who visited our hospital for magnetic resonance angiography (MRA) participated in this study. A 3.0 Tesla Achieva magnetic resonance imaging (MRI) system (Philips, Netherland) and the SENSE NeuroVascular 16-channel coil were employed for both methods. Both methods were applied simultaneously to the same patient. Three TOF stacks were connected to cover the aortic arch through the circle of Willis, and CEA was applied in the same manner. For the quantitative assessment, the acquired images were used to set the regions of interest (ROIs) in the common carotid artery (CCA) bifurcation, internal carotid artery, external carotid artery, middle cerebral artery, and vertebral artery, and to obtain the signal-to-noise ratio (SNR) and the contrast-to-noise ratio (CNR) for the soft tissues. Three radiologists and one radiological resident performed the qualitative assessment on a 5-point scale - 1 point, "very bad"; 2 points, "bad"; 3 points, "average"; 4 points, "good"; and 5 points, "very good" - with regard to 4 items: (1) sharpness, (2) distortion, (3) vein contamination, and (4) expression of peripheral vessels. For the quantitative assessment, we estimated the mean SNR and CNR in each of the 5 ROIs. In general, the mean SNR was higher in TOF angiography (166.1, 205.2, 154.39, 172.23, and 161.95) than in CEA(92.05, 95.43, 84.76, 73.69, and 88.3). Both methods had a similar mean CNR: 67.62, 106.71, 55.9, 73.74, and 63.46 for TOF angiography, and 67.82, 71.19, 60.52, 49.45, and 64.07 for CEA. In all ROIs, the mean SNR was statistically significant (p<0.05), whereas the mean CNR was insignificant (p>0.05). The mean values of TOF angiography and CEA for each item in the qualitative assessment were 4.2 and 4.28, respectively for item 1; 2.93 and 4.55, respectively, for item 2; 4.6 and 3.13, respectively, for item 3; and 2.88 and 4.65, respectively, for item 4. Therefore, TOF angiography had a higher mean for item 3, and CEA had a higher mean for items 2 and 4; there was no significant difference between the two methods for item 1. The results for item 1 were statistically insignificant (p>0.05), whereas the results for items 2~4 were statistically significant (p<0.05). Both methods have advantages and disadvantages and they complement each other. However, CEA is usually applied to a large region covering the aortic arch. Time-of-flight angiography may be useful for people such as infants, pregnant women, CRF patients, and followup patients for whom the use of contrast media can be dangerous or unnecessary, depending on the circumstance.

디지탈영상에서 골판톰의 프랙탈분석 (A fractal analysis of bone phantoms from digital images)

  • 김재덕;김진수;이창율
    • Imaging Science in Dentistry
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    • 제35권1호
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    • pp.33-40
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    • 2005
  • Purpose : (1) To analyse the effect of exposure time, ROI size and one impact factor in the image processing procedure on estimates of fractal dimension; and (2) to analyse the correlated relationship between the fractal dimension and the Cu-Eq value (bone density). Materials and Methods : The cylindric bone phantoms of 6 large and 5 small diameter having different bone densities respectively and human dry mandible segment with copper step wedge were radiographed at 1.0 and 1.2 sec esposure (70 kVp, 7 mA) using one occlusal film and digitized. Eleven rectangular ROIs from 11 cylindric bone phantoms and 4 rectan-gular ROIs from cortical, middle, periodontal regions, and socket of bone were selected. Gaussian blurred Image was subtracted from original image of each ROI and multiplied respectively by 1, 0.8, and 0.5, and then the image was made binary, eroded and dilated once, and skeletonized. The fractal dimension was calculated by means of a box counting method in the software ImageJ. Results : The fractal dimension was decreased gradually with continued bone density decrease showing strong correlations (bone phantom; r> 0.87, bone; r> 0.68) under 70 kVp 1.0 sec M = 0.8. Fractal dimensions showed the significant differerence (p < 0.05) between two different exposure times on the same small ROI of bone phantom. Fractal dimensions between two different sizes of ROI on bone phantom showed the significant differerence (p < 0.05) under 1.2 sec exposure, but did not show it (p > 0.05) under 1.0 sec exposure. Conclusions : Exposure time, ROI size, and modifying factor during subtracting could become impacting on the results of fractal dimension. Fractal analysis with thoroughly evaluated method considering the various impacting factors on the results could be useful in assessing the bone density in dental radiography.

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구내방사선사진의 프랙탈 분석을 이용한 골다공증 예측 (Prediction of osteoporosis using fractal analysis on periapical radiographs)

  • 박금미;정연화;나경수
    • Imaging Science in Dentistry
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    • 제35권1호
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    • pp.41-46
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    • 2005
  • Purpose : The purpose of this study was to investigate whether the fractal dimension and radiographic image brightness of periapical radiograph were useful in predicting osteoporosis. Materials and Methods : Ninety-two postmenopausal women were classified as normal, osteopenia and osteoporosis group according to the bone mineral density of lumbar vertebrae and periapical radiographs of both mandibular molar areas were taken. The ROIs of 358 areas were selected at periapical and interdental areas and fractal dimension and radiographic image brightness were measured. Results : The fractal dimension in normal group was significantly higher than that in osteoporosis group at periapical ROI (P < 0.05). The radiographic image brightness in normal group was higher than that in osteopenia and osteoporosis group. There was significant difference not only between normal and osteopenia group (P < 0.05) but also within osteopenia and osteoporosis group (P< 0.01) at periapical ROI. Significant difference was observed not only between normal and osteopenia group but also between normal and osteoporosis group at interdental ROI (P< 0.01). Positive linear relationship was weakly shown at Pearson correlation analysis between fractal dimension and radiographic image brightness. BMD significantly correlated with fractal dimension at periapical ROI (P< 0.01), and BMD and radiographic image brightness significantly correlated at both periapical and interdental ROIs (P< 0.01). Conclusion : This study suggests that the fractal dimension and radiographic image brightness of periapical ROI may predict BMD. (Korean J Oral Maxillofac Radiol 2005: 35 : 41-6)

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청기산(淸肌散)과 가미청기산(加味淸肌散)이 마우스의 항(抗)알레르기 및 면역반응(免疫反應)에 미치는 영향(影響) (Effects of Cheonggisan and Gagamcheonggisan on the anti-allegic and immune responses in mice)

  • 박은정;김양귀
    • 대한한방소아과학회지
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    • 제12권1호
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    • pp.183-210
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    • 1998
  • Cheonggisan(CGS) is well known for its effect on such allergic disease as urticaria and atopic dermatitis. Gagamcheonggisan(GCGS) was formulated by subtracting several herbs from CGS and adding several herbs to CGS. Even though it is being used frequently in the clinicai medicine for the treatment of above hypersensitivity diseases, basic study to make sure the mechanism of its action is rare. In this study the author tried to know the effect of CGS and GCGS on the vascular permeability, contact dermatitis, granular secretion from mast cells and function of macrophages. The results obtained in this study are as follows : 1. Administration of CGS and GCGS decreased the vascular permeability induced by serotonin and histamine. The decrease by serotonin is more typical and dose-dependent. 2. Administration of CGS and GCGS inhibited foot-pad and ear swelling responses induced by sheep red blood cells and picryl chloride respectively, the inhibition of foot-pad swelling responses is bigger than that of ear swelling responses and both of them are not dependent on the dose3. Treatment of peritoneal mast cells with CGS and GCGS water extract decreased the histamine release triggered by compound 48/80 in a dose dependent fashion 4. Administration of CGS and GCGS increased the phagocvtic activity of peritoneal macrophages and treatment of peritoneal macrophages with CGS activated phagocytic function in a dose dependent fashion. 5. Administration of CGS and GCGS enhanced such reactive oxygen intermediates(ROIs) as superoxide and hydrogen peroxide production from peritoneal macrophages. 6. Treatment of CGS and GCGS activated peritoneal macrophages for the production of ROIs. The above results show that CGS and GCGS decreased the hypersensitivity reactions by inhibiting non-specific inflammatory mediator release and vascular permeability without affecting general immune responsiveness.

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다중 컬러필터 조리개 시스템을 위한 적응적 히스토그램 평활화를 이용한 영상 개선 (Image Enhancement Using Adaptive Region-based Histogram Equalization for Multiple Color-Filter Aperture System)

  • 이은성;강원석;김상진;백준기
    • 대한전자공학회논문지SP
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    • 제48권2호
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    • pp.65-73
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    • 2011
  • 본 논문은 다중 컬러 필터 조리개 (multiple color-filter aperture; MCA) 시스템에서 영역 적응적 히스토그램 평활화를 사용하여 저노출 환경에서도 강건한 새로운 디지털 다중초점 (multifocusing) 방법을 소개한다. MCA 시스템은 획득된 영상의 컬러 채널 간에 발생하는 부정합 (misalignment) 정도를 측정하여 카메라의 거리에 따른 장면의 상대적 심도 정보를 추출한다. 추출된 상대적 심도 정보는 관심영역 (regsion-of-interests; ROIs) 분류 (classification), 정합 (registration), 융합 (fusion) 등의 과정을 통하여 다중초점 영상을 생성한다. 그러나 MCA 시스템은 유한한 구경의 조리개로 때문에 저노출 환경에서 성능의 저하를 초래하게 된다. 이러한 문제를 해결하기 위해 공간 적응적 히스토그램 확장을 이용한다. 실험결과에서 볼 수 있듯이, 제안한 기술은 저노출 환경에서도 콘트라스트가 향상된 다중초점 영상을 복원할 수 있음을 보여준다.

환경 요인에 독립적인 관심 영역 추출을 위한 프레임워크의 개발 (Development of A Framework for Robust Extraction of Regions Of Interest)

  • 김성훈;이광의;허경용
    • 한국컴퓨터정보학회논문지
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    • 제16권12호
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    • pp.49-57
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    • 2011
  • 영상으로부터 관심 영역을 추출하는 작업은 비젼을 이용한 응용 분야에서 첫 번째 단계로 이후 처리 단계에 영향을 미치는 중요한 작업이다. 하지만 관심 영역추출은 조명이나 카메라 등의 주변 환경에 민감하여 일반적으로 문제에 관련된 지식이나 후처리를 도입하여 추출된 영역을 보정하고 있다. 이 논문에서는 환경에 민감하지 않으며 이후 처리 과정에 독립적인 관심 영역 추출을 위한 프레임워크를 제안한다. 제안하는 프레임워크는 차영상과 색상 분포를 이용하여 관심 영역을 추출하며 색상 분포를 학습함으로써 환경의 변화에 적응할 수 있다. 또한 프레임워크의 각 구성 요소들이 독립적으로 동작하는 유연한 구조를 가지므로 확장성이 뛰어나다. 제안하는 프레임워크의 유용성은 동영상에서 손 영역 추출을 통해 확인할 수 있다.