• 제목/요약/키워드: Background counts

검색결과 210건 처리시간 0.023초

Effects of Fully Filling Deep Electron/Hole Traps in Optically Stimulated Luminescence Dosimeters in the Kilovoltage Energy Range

  • Chun, Minsoo;Jin, Hyeongmin;Lee, Sung Young;Kwon, Ohyun;Choi, Chang Heon;Park, Jong Min;Kim, Jung-in
    • Journal of Radiation Protection and Research
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    • 제47권3호
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    • pp.134-142
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    • 2022
  • Background: This study investigated the characteristics of optically stimulated luminescence dosimeters (OSLDs) with fully filled deep electron/hole traps in the kV energy ranges. Materials and Methods: The experimental group consisted of InLight nanoDots, whose deep electron/hole traps were fully filled with 5 kGy pre-irradiation (OSLDexp), whereas the non-pre-irradiated OSLDs were arranged as a control group (OSLDcont). Absorbed doses for 75, 80, 85, 90, 95, 100, and 105 kVp with 200 mA and 40 ms were measured and defined as the unit doses for each energy value. A bleaching device equipped with a 520-nm long-pass filter was used, and the strong beam mode was used to read out signal counts. The characteristics were investigated in terms of fading, dose sensitivities according to the accumulated doses, and dose linearity. Results and Discussion: In OSLDexp, the average normalized counts (sensitivities) were 12.7%, 14.0%, 15.0%, 10.2%, 18.0%, 17.9%, and 17.3% higher compared with those in OSLDcont for 75, 80, 90, 95, 100, and 105 kVp, respectively. The dose accumulation and bleaching time did not significantly alter the sensitivity, regardless of the filling of deep traps for all radiation qualities. Both OSLDexp and OSLDcont exhibited good linearity, by showing coefficients determination (R2) > 0.99. The OSL sensitivities can be increased by filling of deep electron/hole traps in the energy ranges between 75 and 105 kVp, and they exhibited no significant variations according to the bleaching time.

Low-level Laser Therapy with Novel Array of Light Source and Individualized Program for Treatment of Androgenetic Alopecia: A 16-week, Randomized, Double-blind, Sham Device-controlled Study

  • Kim, Jee-Woo;Kwon, Yeo-Seon;Chang, Yoon-Young;Hong, Sung-Ho;Shin, Jung-Won;Na, Jung-Im;Huh, Chang-Hun
    • Medical Lasers
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    • 제9권2호
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    • pp.150-158
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    • 2020
  • Background and Objectives Low-level laser therapy (LLLT) is used widely to promote hair growth in androgenetic alopecia (AGA). This study examined the clinical efficacy and safety of a home-use LLLT device with a newly designed array of light sources and software optimized for individual types of AGA. Materials and Methods The study was a randomized, double-blind, sham device-controlled trial. Forty-eight subjects (39 men and nine women) were assigned randomly in a 2:1 ratio to use either the test device (LG Pra'L HGN1, LG electronics, Korea) or sham device. The subjects used the LLLT device three times a week for 16 weeks. Phototrichogram was used to measure the hair density and hair thickness at 0, 8, and 16-weeks. Adverse events were closely monitored. Results After 16 weeks of using the device, the test group showed a significant increase in hair density and hair thickness compared to the control. In the test group, the hair density increased 6.96 counts/cm2 at eight weeks and 13.67 counts/cm2 at 16 weeks from the baseline. The hair thickness increased 7.21 ㎛ at eight weeks and 11.80 ㎛ at 16 weeks compared to the baseline. Conclusion The home-use LLLT device with a novel array of light sources and an individualized program according to the types of hair loss appears to be an effective and safe treatment modality for both male and female AGA patients.

Poor Prognosis Significance of Pretreatment Thrombocytosis in Patients with Colorectal Cancer: a Meta-Analysis

  • Zhao, Jian-Meng;Wang, Yong-Hong;Yao, Nan;Wei, Kong-Kong;Jiang, Lei;Hanif, Shahbaz;Wang, Zi-Xia
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권9호
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    • pp.4295-4300
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    • 2016
  • Background: Recently, several studies have reported that elevated platelet counts may be associated with the poor prognosis of colorectal cancer. However, conclusions remain controversial. This meta-analysis was therefore designed to analyze and evaluate the prognostic role of preoperative or pretreatment thrombocytosis in patients with colorectal cancer. Materials and Methods: We searched PubMed, EMBASE, the Cochrane Library and Web of Science to March 29th, 2015. The citation lists of included studies were also hand-searched to identify further relevant trials. To investigate the association between thrombocytosis and prognosis of colorectal cancer, the 1-year, 3-year and 5-year survival of each studies were obtained. The odds ratio (OR) with its 95% confidence interval (CI) was used to evaluate the relation of overall survival (OS) between thrombocytosis and normal platelet counts (PLT). Likewise, disease free survival (DFS) was obtained and evaluated. The analysis was performed and assessed using Review Manager 5.2. Results: A total of 14 studies (N=5,566 participants, 11 including 4,468 for OS, 6 including 1,533 for DFS) were included in this meta-analysis, of which seven (N=3810) defined thrombocytosis as a platelet count ${\geq}400{\times}10^9/L$, and 375 (9.8%) patients exhibited pretreatment thrombocytosis. Thrombocytosis have a close relationship with the poor OS of colorectal cancer compared with normal PLT, with the pooled ORs of 1-year, 3-year and 5-year survival being 0.41 [95% CI 0.34-0.51; P<0.001], 0.28 [95% CI 0.21-0.38; P<0.001] and 0.26 [95% CI 0.20-0.34; P<0.001], respectively. For DFS, the same results were showed as the pooled ORs of 1-year, 3-year and 5-year survival respectively being 0.34 [95% CI 0.24-0.50; P<0.001], 0.31 [95% CI 0.23-0.43; P<0.001] and 0.25 [95% CI 0.18-0.34; P<0.001]. Conclusions: This meta-analysis indicated that thrombocytosis may predict poor prognosis for patients with colorectal cancer, and platelet counts may be a cost-effective and noninvasive marker.

Korean Red Ginseng affects ovalbumin-induced asthma by modulating IL-12, IL-4, and IL-6 levels and the NF-κB/COX-2 and PGE2 pathways

  • Lee, Soon-Young;Kim, Min-Hee;Kim, Seung-Hyun;Ahn, Taeho;Kim, Sung-Won;Kwak, Yi-Seong;Cho, Ik-Hyun;Nah, Seung-Yeol;Cho, Seung-Sik;Park, Kyung Mok;Park, Dae-Hun;Bae, Chun-Sik
    • Journal of Ginseng Research
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    • 제45권4호
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    • pp.482-489
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    • 2021
  • Background: Asthma is an incurable hyper-responsive disease of the pulmonary system that is caused by various allergens, including indoor and outdoor stimulators. According to the Global Asthma Network, 339 million people suffered from asthma in 2018, with particularly severe forms in children. Numerous treatments for asthma are available; however, they are frequently associated with adverse effects such as growth retardation, neurological disorders (e.g., catatonia, poor concentration, and insomnia), and physiological disorders (e.g., immunosuppression, hypertension, hyperglycemia, and osteoporosis). Methods: Korean Red Ginseng has long been used to treat numerous diseases in many countries, and we investigated the anti-asthmatic effects and mechanisms of action of Korean Red Ginseng. Eighty-four BALB/c mice were assigned to 6 treatment groups: control, ovalbumin-induced asthma group, dexamethasone treatment group, and 3 groups treated with Korean Red Ginseng water extract (KRGWE) at 5, 25, or 50 mg/kg/day for 5 days. Anti-asthmatic effects of KRGWE were assessed based on biological changes, such as white blood cell counts and differential counts in the bronchoalveolar lavage fluid, serum IgE levels, and histopathological changes in the lungs, and by examining anti-asthmatic mechanisms, such as the cytokines associated with Th1, Th2, and Treg cells and inflammation pathways. Results: KRGWE affected ovalbumin-induced changes, such as increased white blood cell counts, increased IgE levels, and morphological changes (mucous hypersecretion, epithelial cell hyperplasia, inflammatory cell infiltration) by downregulating cytokines such as IL-12, IL-4, and IL-6 via GATA-3 inactivation and suppression of inflammation via NF-κB/COX-2 and PGE2 pathways. Conclusion: KRGWE is a promising drug for asthma treatment.

18F-FDG와 99mTcO4-를 이용한 당일 검사 시 상호 영향에 대한 Phantom 연구 (Phantom Study of the Mutual Influences Between 18F-FDG and 99mTcO4- on the Same Day)

  • 함준철;박민수;반영각;임한상;김재삼
    • 핵의학기술
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    • 제18권2호
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    • pp.68-72
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    • 2014
  • 핵의학 검사는 반감기로 인한 동위원소의 잔류로 당일에 두 가지 검사를 시행하는데 어려움이 있다. 본 연구는 $^{18}F$-FDG와 $^{99m}TcO_4{^-}$의 상호 영향을 연구함으로써 당일 검사를 진행할 경우 고려될 사항에 대해 알아보고자 한다. NEMA-1994 Phantom을 이용하여 세 번의 실험을 진행했다. 첫 실험은 $^{99m}TcO_4{^-}$을 HOT과 BKG 비 4:1로 만들어 GE사의 INFINIA 장비로 SPECT를 시행하였고, BKG 영역에 $^{18}F$-FDG 37 MBq을 주입 후 동일 조건으로 60분에 1회씩 13회 Scan 했다. 두 번째는 $^{18}F$-FDG를 HOT과 BKG 비 4:1 로 만들어 GE사의 PET/CT Discovery 600 에서 Scan 하였고, BKG 영역에 $^{99m}TcO_4{^-}$을 148 MBq 주입 후 동일 조건으로 60분에 1회씩 6회 Scan 했다. 마지막 실험은 $^{18}F$-FDG를 HOT과 BKG 비 4 : 1로 만들고 1 Bed Scan 후 $^{99m}TcO_4{^-}$을 148 MBq 및 296 MBq씩 증가 시키며 같은 조건으로 1 Bed Scan했다. HOT과 BKG 영역의 비, CNR 혹은 SNR 그리고 총 획득 계수를 측정 후 비교 했다. $^{18}F$-FDG는 SPECT 시행 시 비율 및 CNR에 유의한 차이를 보였다(p>0.05). $^{99m}TcO_4{^-}$는 PET/CT 시행 시 비율 및 SNR이 유의한 차이를 보이지 않았다(p<0.05). $^{99m}TcO_4{^-}$이 PET/CT 검사의 Total Counts를 감소시킨다는 결과를 획득했다. PET/CT 검사를 한 경우 12시간 까지도 $^{99m}TcO_4{^-}$을 이용한 검사에 영향을 미칠 수 있으며, $^{99m}TcO_4{^-}$를 먼저 시행한 경우에는 PET/CT 검사에 SUV 및 SNR에 영향은 없지만 검출 효율을 감소시켰다. 당일 검사 시에는 $^{99m}TcO_4{^-}$을 이용한 검사를 먼저 진행하고 PET/CT의 검사 시간을 늘려 검출 효율을 보완하는 방법을 권장하고자 한다.

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Gamma Camera에 있어 측면 선란선의 영향에 대한 평가 (The Evaluation of Lateral Scatter Ray of Gamma Camera)

  • 김재일;이은별;조성욱;노경운;강건욱
    • 핵의학기술
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    • 제22권1호
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    • pp.46-50
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    • 2018
  • 검출기 외부에 강한 선원은 collimator와 상호 작용으로 산란선이 만들어지게 되는데, 그 산란선이 영상에 얼마나 영향을 주는지 평가하고자 한다. SKY LITE를 사용하여, phantom study의 경우, $^{99m}Tc$ 1.11 GBq를 점선원으로 만들어 검출기 주변을 $10^{\circ}$ 간격으로 돌아가면서 측정하여 각 각도에서의 산란선의 정도를 계수율과 스펙트럼으로 분석을 하였다. Patient study의 경우, 3-phase bone scan을 하는 환자를 대상으로, blood flow와 blood pool 영상을 획득하면서 산란선의 양과 스펙트럼을 분석하였다. 추가로 blood pool 검사 시, 환자의 손위에 납가운을 올려놓고 영상을 획득하였고, 환자의 몸에 납가운을 입히고 영상을 획득하여 각 영상에서의 산란선과 스펙트럼을 비교, 평가하였다. 그 결과, phantom study의 경우, 후방에서는 산란선의 없었지만, 측면부터 전방 $50^{\circ}$ 까지는 산란선이 많이 검출 되었다. patient study의 경우 blood flow 영상과 blood pool 영상에서 환자 몸에서 나온 감마선으로 인해 생긴 산란선이 입사됨을 알 수 있었다. 그리고 납가운은 손 위를 차폐하는것 보다, 환자 몸을 차폐 하는 것이 산란선이 많이 줄었다. 그러므로 외부에 강한 선원이 존재하고, hand blood flow, blood pool 검사처럼 계수 자체가 낮을 검사를 할 경우, 몸에서 나오는 선원 자체를 차폐하는 것이 산란선을 줄이는데 보다 효과가 있으며, 영상에서도 배후 방사선을 줄이는데 효과가 있음을 알 수 있었다.

Surfactant Protein A mRNA을 이용한 유전자 재결합 반응에서 비특이성 RNA의 첨가에 의한 특이성 검정 (Assessment of the Specificity of A Hybridization of Surfactant Protein A by Addition of Non-specific Rat Spleen RNA)

  • 김병철;김미옥;김태형;손장원;윤호주;신동호;박성수
    • Tuberculosis and Respiratory Diseases
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    • 제56권4호
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    • pp.393-404
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    • 2004
  • 연구배경 : 유전자 재결합 반응에 있어서 다른 종류의 RNA의 첨가에도 불구하고 유전자 반응에 영향이 없어야 여타 실험의 정량적 분석에 이용이 가능하다. 이에 저자들은 쥐를 대상으로 filter hybridization방법과 SP-A mRNA을 이용하여 비특이성 RNA 즉, 쥐의 비장 RNA의 첨가가 surfactant protein A (SP-A)의 유전자 재결합반응의 linearity, 상관계수 및 특이성에 미치는 영향을 알아보기 위하여 이 연구를 시행하였다. 방 법 : SP-A transcript mRNA의 정량, 즉 0, 0.1, 0.5, 1 및 2.5 ng에 비특성 RNA 즉 비장 RNA를 각각 0,1, 5 및 $10{\mu}g$을 첨가하여 filter hybridization 방법을 이용하여 SP-A mRNA양과 cpm과의 연관성을 비교정량측정하여 각각의 linearity, 상관계수 및 특이성의 분자생물학적 정도관리에 대한 비교 관찰을 하기 위하여 이 연구를 시행하였다. 결 과 : 1. 쥐의 spleen RNA 0, 1, 5, 10 및 $20{\mu}g$에 대한 cpm과의 표준곡선 및 상관계수는 Y=0.13X-19.35(X=cpm, Y=spleen RNA input)이고, 상관계수는 0.98이었다. 2. SP-A sense 전사체 0, 0.1, 0.5, 1.0, 2.5 및 5 ng에 대한 cpm과의 표준곡선 및 상관계수는 Y=0.00066X-0.046 (X=cpm, Y=SP-A mRNA 전사체)이고, 상관계수는 0.99이었다. 3. 쥐의 비장 RNA $1{\mu}g$을 첨가 후 SP-A sense 전사체 0, 0.1, 0.5, 1.0, 2.5 및 5 ng에 대한 cpm과의 표준곡선 및 상관계수는 Y=0.00056X-0.051(X=cpm, Y=SP-A mRNA 전사체)이고, 상관계수는 0.99이였다. 쥐의 비장 RNA $5{\mu}g$을 첨가 후 표준곡선은 Y=0.00065X-0.088 (X=cpm, Y=SP-AmRNA 전사체)이고, 상관계수는 0.99이였다. 쥐의비장 RNA $10{\mu}g$을 첨가 후 표준곡선은 Y=0.00051X-0.10 (X=cpm, Y=SP-A mRNA 전사체)이고, 상관계수는 0.99이었다. 결 론 : 이상의 결과는 비특이성 RNA인 비장 RNA의 첨가 후 SP-A sense mRNA양과 cpm과의 상관관계는 sense 유전자와 anti-sense 유전자의 유전자 재결합 반응에 있어서 다양한 양의 비특이성 RNA의 첨가나 오염에도 불구하고 linearity, 상관계수 및 그 특이성이 잘 유지됨을 입증해 준 결과라 생각된다.

중등학교 가정과 교사들의 주거개념에 대한 중요도 인지 및 주거학 교육방법에 관한 연구 - 부산시를 중심으로 - (Scondary home economics teachers' opinions reganiding importance of teaching verious housing concepts and use of teaching method and media)

  • 최영순
    • 한국주거학회논문집
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    • 제1권1호
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    • pp.113-128
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    • 1990
  • This study was designed to identify the problems in teaching housing course at secondary level. The main tasks of Investigation were to: (1) identify appropriate housing concepts to be taught at secondary school, (2) determine the Kinds of media and methods used for teaching housing course at secondary school. The questionnaire was divided Into three sections: (1) the teacher`s background, (2) the teacher`s opinion regarding the importance of various housing topics to teaching. (3) what type of media and methods were used by teachers. Data were collected In Pusan during November 1959. The Sample, 150Home Economics teacher was randomly selected from secondary school list in Pusan. Responses from 122 Home Economics teachers, were processed by the S.P.S.S. computer program. and N.P.E.R.C using for frequency counts and percentages to analyze the data from all three sections of questionnaire. One-way Analysis of Variance and Newman-kuels Multiple Comparison test were used to reject or accept the hypotheses. The major findings were: (1) there were some difference between teachers` opinions regarding the importance of various housing topics to teach and teachers actural practice of teaching housing concepts and topics, (2) teachers taught housing concepts which were important to teach by their opinion, even though those concepts were neglected in textbook, (3) teachers did not use a various of media and methods for their teaching housing class, (4) the important reasons given why the teachers for not using the various media and methods were because of undesirable educational situations, and (5) there were some significant differences between teachers` background and teachers` opinion regarding importance of teaching topics in housing class at secondary school, using media and methods.

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갑상선섭취율검사시(甲狀腺攝取率檢査時) 측정조건(測定條件)에 관(關)한 조사연구(調査硏究) (Study on Measurements in Thyroid Uptake Rate Test)

  • 경광현;김화곤
    • 대한방사선기술학회지:방사선기술과학
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    • 제4권1호
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    • pp.55-62
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    • 1981
  • This study was conducted, during the period of 20-30th, July in 1981, to survey measurement methods in thyroid uptake rate test in Seoul city. The results were summarized as follows: 1. For the great part of nuclear medcine department, a mount of radioiodine($^{131}I$) administrated to the patients was $50-100{\mu}Ci$ in thyroid uptake rate test. 2. Distribution of scintillation, counter with crystal size of $1\frac{1}{2}inch$ was 43%, 3inch(22%), 2.5inch(14%) and $2\frac{1}{2}inch$ was 7% in RAI uptake rate test. 3. When RAI uptake rate test was performed, distribution of collimator in use was flat field type collimator(78%) in general and cylindrical type collimator was 22%. 4. High voltage applied to the P-M tube was $900{\sim}1000V$(50%) and most units provided $3{\sim}15%$ of the window range for the $^{131}I$ peak $\gamma-ray$ energy. 5. Distribution on the use of neck phantom for measurements standard solution was 57% and distribution of b filter in use for room background counts and extrathyroidal tissue was 43% and 50%. 6. The distance between the counter and the source was 25cm(58%) in measuring radioactivity of standard solution, thyroid tissue and background radioactivity count. 7. The early uptake measurements(2, 4, 6 hours) are done after administration of the radioiodine dose and also 24-hour and 48-hour uptake measurements are done in routine test.

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환경 방사능 처리기술에서의 Compton suppression 및 Unsuppression system을 이용한 토양시료의 MDA 측정 (Measurement of MDA of Soil Samples Using Unsuppression System and Compton Suppression of Environmental Radioactivity in Processing Technology)

  • 강수만;임인철;이재승;장은성;이미현;권경태;김창태
    • 한국방사선학회논문지
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    • 제8권6호
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    • pp.293-299
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    • 2014
  • Compton suppression 장치는 Compton 산란 반응을 이용하여, 스펙트럼의 Compton continuum 부분을 억제함으로써 Compton continuum 영역 내에서의 감마선 피크들의 분석을 보다 명확하게 할 수 있게 해주는 장치이다. 표층토양 시료에서 검출된 인공 방사능인 $^{137}Cs$과 자연 방사능인 $^{40}K$핵종의 방사능 농도 값들에 대한 방사능 계수치가 백그라운드를 상회하는 측정값이 발생되거나, 불필요한 방해피크나 비해석 대상 피크에 대하여 검출된 표준선원의 방사능 농도 값들의 실측치에 대한 background를 비억제 스펙트럼(Compton Unsuppression)과 억제 스펙트럼(Compton suppression)을 적용시켜 측정 에너지에 대한 교정을 알고자 점선원인 $^{137}Cs$을 거리별에 따라 측정하여, 몬테칼로 시뮬레이션과 비교 분석함으로서 효율적인 검출 능력을 얻고자 함이며, Compton 억제 인자를 보면 거리가 멀어짐에 따라 CSF 값이 클수록 더 많은 Compton suppression가 이루어졌음을 알 수 있고, $^{137}Cs$을 이용한 컴프턴 비억제 모드와 억제모드로 측정된 스펙트럼에서 컴프턴 연속에 의한 백그라운드가 감소함을 알 수 있었다.