• 제목/요약/키워드: background count

검색결과 336건 처리시간 0.026초

SPECT/CT에서 인공고관절에 대한 감쇠보정지도(Attenuation Map)의 매개변수 변화에 따른 금속 인공물(Metal Artifact)의 영향 평가 (Evaluation of the Effect of Metal Artifacts Varying the Parameters of the Attenuation Map for the artificial Hip Joint in SPECT/CT)

  • 김상규;김정열;박민수;조승현;임한상;김재삼
    • 핵의학기술
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    • 제18권2호
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    • pp.3-7
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    • 2014
  • CT를 기반으로 감쇠보정이 시행되는 SPECT/CT 검사에서는 금속 삽입물에 의한 선속경화현상으로 인접한 부위의 과대평가를 유발하며, 영상의 질을 저하시킨다. 이에 대해, 본 연구에서는 인공고관절이 삽입된 팬텀을 이용하여 감쇠보정지도의 매개변수 변화에 따른 금속 인공물이 SPECT/CT 영상에 미치는 영향을 알아보고자 한다. SPECT/CT 장비는 Siemens사의 Symbia T16을 사용하였다. SPECT/PET 팬텀에 인공고관절을 삽입하고, CT영상에서 Bright Streak 영역에 직경 17 mm의 구를 배후방사능 대비 8배가 되도록 Tc-99m을 채웠다. 이후 감쇠보정지도에서 Wide Beam Coefficient[수동모드(0.1~0.9), 자동모드]변화에 따른 열소와 배후방사능의 계수를 측정하였고, 고관절의 유무에 따라 Metal과 Non-Metal의 병소 대 배후방사능 비(Region to Background Ratio, RBR)를 산출 및 비교 분석하였다. 수동모드의 값이 증가할수록 Metal과 Non-Metal의 열소 계수는 증가하는 경향을 나타냈으며, 수동모드 0.4와 0.5에서 두 군과의 열소 계수비가 가장 일치하게 나타났다(수동모드 0.4=1.001, 0.5=0.999). 또한 $RBR^{Metal}$$RBR^{Non-Metal}$의 비는 자동모드에서 1.135이였고, 수동모드 0.4와 0.5에서 통계적으로 유의한 차이를 보이지 않았다(0.4=0.999, 0.5=1.028, p=0.78). 감쇠보정지도에서 Wide Beam Coefficient의 자동모드는 13.52% 과 보정 되는 것을 알 수 있었으며, 수동모드 중 0.4와 0.5에서 인공물에 의한 과 보정을 최소화 할 수 있었다. 이를 활용하여 환자에게 적용하기 위해서는 추가적인 연구가 이루어져야 할 것이며, 고관절전치환술 환자의 인공고관절 주변에서 금속 인공물에 의한 과 보정을 감소시켜 진단능을 향상시킬 수 있을 것으로 사료된다.

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PET/CT 영상 획득 시 사전설정법 차이에 따른 영상 질 평가 (Evaluation of the Image Quality According to the Pre-set Method in PET/CT Image)

  • 박선명;이혁;홍건철;정은경;최춘기;석재동
    • 핵의학기술
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    • 제15권2호
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    • pp.41-46
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    • 2011
  • 영상장치를 이용한 검사 시 영상의 질은 검사결과와 밀접하게 연관되어 있으며, 이는 영상획득 조건들과 이에 대한 평가방법으로 인해 달라 질 수 있다. 본 연구에서는 영상획득 시 사전설정법(Pre-set method)차이에 따른 영상의 질을 평가하였다. 장비는 PET/CT Discovery STe16(GE Healthcare, Milwaukee, USA)을 사용하였으며, Chest PET Phantom (실험 1)과 94 NEMA Phantom (실험 2)을 이용하였다. 실험 1의 경우 3.5, 6.0, 8.6 kBq/mL, 실험 2의 경우는 3.3, 5.5, 7.7, 9.9, 12.1, 16.5 kBq/mL의 $^{18}F$-FDG를 채웠고, 열소와 배후방사능과의 방사능 농도는 4:1의 비율을 유지하였다. 각 실험은 CT 투과촬영 후 3D로 2분 30초/프레임으로 시간설정법(Time-set method)과 1억 계수의 계수설정법 (Count-set method)을 적용하여 방출촬영 하였다. 영상의 질에 대한 평가는 잡음 등가 계수율 (Noise Equivalent Count Rate, NECR)과 신호 대 잡음비 (Signal to Noise Ratio, SNR)를 이용하였다. 실험 1에서 NECR과 SNR은 방사능 농도의 증가에 따라 시간설정법에서 53.7, 66.9, 91.4 과 7.9, 10.0, 11.7로 평가 모두에서 증가함을 보였으나, 계수설정법은 53.8, 69.1, 97.8과 14.1, 14.7, 14.4로 SNR은 NECR과 다르게 증감현상을 보이지 않았다. 또 다른 모형실험인 실험 2에서도 NECR과 SNR은 방사능 농도가 증가에 따라 시간설정법에서 45.1, 70.6, 95.3 115.6 134.6 162.2 과 7.1, 8.8, 10.6, 11.5, 12.7, 14.0으로 증가함을 보였으나, 계수설정법에서는 42.1 67.3 92.1 112.2 130.7 158.7 과 15.2, 15.9, 15.6, 15.4, 15.5, 14.9로 실험 1에서와 마찬가지로 SNR에서는 증감현상을 보이지 않았다. 사전설정법 변화와 관계없이 단위 질량당 방사능량 증가는 영상의 질도 비례하여 향상된다. 그러나 동일한 단위 질량당 방사능량에서는 영상획득의 시간을 늘려 총계수값을 증가시켜도 NECR에 영향을 주지는 않는다. 이는 NECR을 이용한 영상 질 평가는 영상획득 시 얻은 총 계수 값보다는 단위 시간당의 계수율이 영향을 준다는 것을 의미한다고 할 수 있다. 실험 모두에서 계수설정법으로 얻은 경우에는 단위 질량당 방사능량의 증가에도 불구하고 거의 비슷한 SNR값을 보이게 된다. 따라서 좋은 질의 영상을 얻기 위해서는 총 계수값의 증가보다는 단위질량당 방사능량을 높여야 하며, SNR만을 이용한 영상의 질에 대한 평가는 적절하지 않을 수 있다는 점을 고려하여야 한다.

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도체탕(導滯湯) 위주의 한방치료로 호전된 활동성 궤양성 대장염 환자 치험 1례 (A Case Report of a Patient with Active Ulcerative Colitis Treated with Do-Che Decoction-based Korean Medicine)

  • 윤성우
    • 대한암한의학회지
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    • 제17권2호
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    • pp.17-22
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    • 2012
  • Background : Sulfasalazine for treating ulcerative colitis has a clinical limitation due to its adverse effects. This case is about a patient with ulcerative colitis who could not tolerate sulfasalazine and was improved by Do-che decoction-based Korean medicine. Method and Results : Purulent and bloody diarrhea more than 20 times a day, mild fever, chilling and tenesmus were main symptoms of this patient who was diagnosed as ulcerative colitis 10 years ago. Do-che decoction-based Korean medicine which was recommended for purulent and bloody diarrhea in Dong-Ui-Bo-Gam, the classic literature of Traditional Korean Medicine was given to the patient for more than 1 month. After treatment, the frequency of purulent and bloody diarrhea, tenesmus and fever was decreased remarkably, and C-reactive protein, erythrocyte sedimentation rate, white blood cell count and maximum temperature also dropped to the normal range. Conclusion : Do-che decoction-based Korean medicine has a potential effect and may be a alternative therapeutic option in patients with ulcerative colitis who cannot tolerate sulfasalazine due to its adverse effects.

천연염색(天然染色) 의상제품(衣類製品)의 구매실태(購買實態) 조사(調査) 연구(硏究) (제1보)(題1報)-보유(保有) 현황(現況)과 착용(着用)이미지를 중심(中心)으로- (A Study on the Purchasing Condition of Natulal-dyed Clothing Product I - Focusing on the Holding Conditions and Wearing Images-)

  • 조영아
    • 패션비즈니스
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    • 제11권4호
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    • pp.1-17
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    • 2007
  • The purpose of this study was to provide for the useful fundamental data to enterprise which produces the natural-dyed clothing products by investigating with the holding conditions and pursuit of wearing images. The subjects were females aged 20 to 59, a questionnaire was developed by the researcher and distributed to 237 females. A sample of 223 females responded to the questionnaire. Data analyses were processed by SPSS WIN 10.0 Program; Frequency count and percentage, $X^2-test$, ANOVA and Duncan's multiple range test were used for statistical analysis. The results of this study were as follows: First, there were significant differences in holding items, period and private ownership according to age, any academic background and a monthly income. Second, the result by classification of the pursuit of wearing images could be identified four factors: factor 1) sexual and feminine image, factor 2) simple and common image, factor 3) comfortable and natural image and factor 4) dynamic image.

정량화한 $^{99m}Tc$-DMSA 신섭취율의 공식표 (Formal Charts for Qnantified $^{99m}Tc$-DMSA Renal Uptake Rates)

  • 문태용;김용기;황수희;윤종병;성경탁
    • 대한핵의학회지
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    • 제27권2호
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    • pp.248-255
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    • 1993
  • To Assessment of the quantified renal uptake rates in every $^{99m}Tc$-DMSA scan tests of patients is actually difficult because of time consumption and complicated calculations required to measure the correct dose of the infused radionulide and radiation decay, the adjustment for the depth of kidney and the subtraction of background count. We've formulated two regression models for the quantified renal uptake rates[I] from the simple renal uptake rates[H] with a square shaped ROI (Region-Of-Interest) in 25 cases (Group 1) and with a kidney shaped ROI in 37 cases (Group 2), respectively. The regression model for the Group 1 was $[I]_1$=0.885 $[H]_1$-4.575 (P<0.005), and for the Group 2 was $[I]_2$=0.591 $[H]_2$-2.105 (p<0.005). The formal charts were clinically convenient to evaluate the individual renal functions in patients with $^{99m}Tc$-DMSA renal scan.

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Monitoring of Microorganisms Added into Oil-Contaminated Microenvironments by Terminal-Restriction Fragment Length Polymorphism Analysis

  • JUNG SEONG-YOUNG;LEE JUNG-HYUN;CHAI YOUNG-GYU;KIM SANG-JIN
    • Journal of Microbiology and Biotechnology
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    • 제15권6호
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    • pp.1170-1177
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    • 2005
  • Terminal-restriction fragment length polymorphism (T-RFLP) analysis was used to monitor inoculated oil-degrading microorganisms during bioremedial treatability tests. A pair of universal primers, fluorescently labeled 521F and 1392R, was employed to amplify small subunit rDNA in order to simultaneously detect two bacterial strains, Corynebacterium sp. IC10 and Sphingomonas sp. KH3-2, and a yeast strain, Yarrowia lipolytica 180. Digestion of the 5'-end fluorescence/labeled PCR products with HhaI produced specific terminal-restriction fragments (T-RFs) of 185 and 442 bases, corresponding to Corynebacterium sp. IC10 and Y. lipolytica 180, respectively. The enzyme NruI produced a specific T-RF of 338 bases for Sphingomonas sp. KH3-2. The detection limit for oildegrading microorganisms that were inoculated into natural environments was determined to be $0.01\%$ of the total microbial count, regardless of the background environment. When three oil-degrading microorganisms were released into oil-contaminated sand microenvironments, strains IC10 and 180 survived for 35 days after inoculation, whereas strain KH3-2 was detected at 8 days, but not at 35 days. This result implies that T-RFLP could be a useful tool for monitoring the survival and relative abundance of specific microbial strains inoculated into contaminated environments.

액체섬광계수법을 이용한 방사성탄소 연대측정법 연구 (Study on the Radiocarbon Dating with Liquid Scintillation Counting)

  • 김낙배;우형주;홍완;조수영
    • 분석과학
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    • 제5권4호
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    • pp.381-387
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    • 1992
  • 액체섬광계수법을 방사성탄소 연대측정에 이용하기 위하여 섬광용액과 섬광용액 대 벤젠의 부피비, 그리고 베타선 스펙트럼 측정범위를 변화시키면서 삼중수소의 영향을 최소화하고 최대 FOM을 얻기 위한 저준위 액체섬광계수기의 최적계측조건을 결정하였다. 결정된 조건하에서 백그라운드 계수율을 $2.26{\pm}0.03cpm$ 까지 낮출 수 있었으며, 이때의 최대 측정가능 연대는 약 40,000년에 이르렀다. 또한 고개시료 및 토탄시료 등의 실제시료에 적용하여 측정계의 실용성을 확인하였다.

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가미열다한소탕(加味熱多寒少湯) 투여후 아토피 피부염 환자의 임상상 변화에 대한 연구 (A study on the alteration of general characteristics and therapeutic effect of GamiYeoldahansotang(加味熱多寒少湯) in patients with Atopic Dermatitis)

  • 정환수;이진용
    • 대한한방소아과학회지
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    • 제15권2호
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    • pp.177-188
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    • 2001
  • Background : Atopic Dermatitis is thought to be a common and chronic relapsing inflammatory skin disease that probably results from allergic reaction. Because it make some serious problems in children, it is needed to treat and at least subside symptoms. Objective : The aim of this study was to evaluate the efficacy of GamiYeoldahansotang(加味熱多寒少湯) for treating Atopic Dermatitis and survey the general characteristics in children with Atopic Dermatitis. Method : Atopic Dermatitis with typical clinical symptoms were included in this study. Forty two patients were treated with hot water extract of GamiYeoldahansotang(加味熱多寒少湯) for four weeks. Clinical evaluation were made by Jacob T scoring system before and after treatment. Total Serum IgE, Eosinophil count were also conducted. Results : Reduction in body surface area was not observed. But significant reductions of severity scores before and after adminstration of GamiYeoldahansotang(加味熱多寒少湯) were observed in all of three groups: mind, moderate, severe. specially severe intensity group was very statistically significant.(p<0.05) Conclusion : We speculate that GamiYeoldahansotang(加味熱多寒少湯) has some therapeutic effects in mitigating the symptoms of Atopic Dermatitis.

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Cytoprotective effect of rhamnetin on miconazole-induced H9c2 cell damage

  • Lee, Kang Pa;Kim, Jai-Eun;Park, Won-Hwan
    • Nutrition Research and Practice
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    • 제9권6호
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    • pp.586-591
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    • 2015
  • BACKGROUND/OBJECTIVES: Reactive oxygen species (ROS) formation is closely related to miconazole-induced heart dysfunction. Although rhamnetin has antioxidant effects, it remained unknown whether it can protect against miconazole-induced cardiomyocyte apoptosis. Thus, we investigated the effects of rhamnetin on miconazole-stimulated H9c2 cell apoptosis. MATERIALS/METHODS: Cell morphology was observed by inverted microscope and cell viability was determined using a WelCount$^{TM}$ cell proliferation assay kit. Miconazole-induced ROS production was evaluated by fluorescence-activated cell sorting with 6-carboxy-2',7'-dichlorofluoroscein diacetate ($H_2DCF$-DA) stain. Immunoblot analysis was used to determine apurinic/apyrimidinic endonuclease 1 (APE/Ref-1) and cleaved cysteine-aspartic protease (caspase) 3 expression. NADPH oxidase levels were measured using real-time polymerase chain reaction. RESULTS: Miconazole (3 and $10{\mu}M$) induced abnormal morphological changes and cell death in H9c2 cells. Rhamnetin enhanced the viability of miconazole ($3{\mu}M$)-treated cells in a dose-dependent manner. Rhamnetin (1 and $3{\mu}M$) treatment downregulated cleaved caspase 3 and upregulated APE/Ref-1 expression in miconazole-stimulated cells. Additionally, rhamnetin significantly reduced ROS generation. CONCLUSIONS: Our data suggest that rhamnetin may have cytoprotective effects in miconazole-stimulated H9c2 cardiomyocytes via ROS inhibition. This effect most likely occurs through the upregulation of APE/Ref-1 and attenuation of hydrogen peroxide levels.

한라산 흑오미자의 자생환경 및 삽목증식 연구 (A Study on the Native Environment and Cutting Propagation for the Black-berry Magnolia Vine [Schisandra repanda (Siebold & Zucc.) Radlk] in Halla Mountain)

  • 부재윤;김주성
    • 한국약용작물학회지
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    • 제28권5호
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    • pp.354-359
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    • 2020
  • Background: The recent, decline in Black-berry Magnolia Vine (Schisandra repanda; BMV) native to Jeju Island, Korea, has raised concerns about the causes of this decline. We investigated the native environment of S. repanda and evaluated its propagation through cuttings to provide preliminary data for its restoration in Jeju Island. Methods and Results: The native environment of the BMV in the Hallasan National Park was surveyed and the climatic variables (temperature and humidity) were analyzed. The effects of the sex of the donor plant (male/female) type of cutting (softwood/hardwood), and treatment with a plant growth regulator (indole-3-butylic acid/rootone) on the rooting of BMV were investigated. Additinallly, the rooting rate, root count, and root length, as well as temperature and humidity were measured in the vinyl moist chambers. BMV was observed in 63 plants distributed from 567 m to 1,364 m above sea level of the Hallasan National Park. In the cutting experiment, the rooting rate was 71.9%, and it was higer in female plants (75.0%) than in male plants (68.8%). Conclusions: The mass propagation of BMV through cuttings valuable for its restoration as without such safeguard measures, the population could face extinction within a few decades.