• Title/Summary/Keyword: Background control

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Comprehension and Appropriate Use of a Flood Table on a Gamma Camera (감마 카메라의 Flood Table에 대한 이해와 적절한 이용)

  • Kim, Jae-Il;Im, Jeong-Jin;Kim, Jin-Eui;Kim, Hyun-Joo
    • The Korean Journal of Nuclear Medicine Technology
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    • v.15 no.1
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    • pp.29-33
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    • 2011
  • Background and Purpose: Uniformity is the one of the important quality control features with respect to gamma cameras. To maintain adequate uniformity, we must acquire suitable flood table (=flood map) data because the flood table effects energy, and the type or dose of input radiation. Therefore, in this study we evaluated the difference in uniformity when uniformity does not match between the type of input radiation and the flood table data or collimator type. Subjects and Methods: For input radiation, we prepared 370 MBq of $^{57}Co$, $^{99m}Tc$, and $^{201}Tl$. Using SKYLight (Philips) and Infinia gamma cameras (GE), we acquired nine uniformity data that were corrected by technetium, cobalt flood table and did not corrected image for the three sources. Additionally, we acquired two uniformity images with a collimator that were corrected by intrinsic and extrinsic flood tables. Using this data, we evaluated and compared the uniformity values. Results: In the case of the SKYLight gamma camera, the uniformities of the images that matched between the input radiation and flood table with respect to $^{99m}Tc$ and $^{57}Co$ were better than the unmatched uniformity (3.96% vs. 5.69% ; 4.9% vs. 5.91%). However, because there was no thallium flood table, the uniformities of images at Tl were significantly incorrect (7.49%, 7.03%). The uniformities of the Infinia gamma camera had the same pattern as the SKYLight gamma camera (3.7% vs. 4.5%). Moreover, the uniformity of the $^{99m}Tc$ image acquired with a collimator and corrected by an extrinsic flood table was better than the intrinsic flood table (3.96% vs. 6.28%). Conclusion: Correcting an image by a suitable flood table can help achieve better uniformity for a gamma camera. Therefore, we have to acquire images with suitable uniformity correction, and update the flood table periodically. Whenever we acquire a nuclear medicine image, we always have to check the appropriate flood table according to the acquired condition.

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Health Assessment of Shift Workers in a Automobile Manufacturing Plant (자동차공장 교대작업 근로자들의 건강상태평가)

  • Lee, Jung-Jeung;Chung, Jong-Hak
    • Journal of Preventive Medicine and Public Health
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    • v.28 no.1 s.49
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    • pp.103-121
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    • 1995
  • An investigation on psychophysiological health and social well-being of shift workers been carried out on workers of a automobile manufacturing plant in Ulsan, for 1 month from April, 1993. This cross-sectional survey compared shift workers(n=544) with day workers(n=115). Each subject completed a questionnaire about his personal habit, background, shift schedule, sleep and eating patterns, subjective digestive symptom and psychological well-being and distress using the General Well-Being Schedule(GWB) by self administrated questionnaire that was developed for the U.S. Health and Nutrition Examination Surveys (HANES I). Chi-square analysis was used for discontinuous data and the t-test was used for continous data to determine whether differences noted between the two groups. In terms of sleep quality, a greater percentage of shift workers frequently had trouble getting back to sleep once awakend(p<0.01), and a greater percentage of shift workers awakend tired or sleepy frequently more often than day workers(p<0.05). In rating the quality of their sleep, more shift workers rated their sleep fair to poor than day workers, and greater percentage of shift workers felt tired or sleepy at work two or more times per week(p<0.01) and a much higher percentage of shift workers felt tired or sleepy after work every days(p<0.01). In terms of sleep patterns, a much higher percentage of day workers reported uninterrupted sleep per 24hours than shift workers. The shift workers reported different eating patterns from day workers but there were no statistically significant and rate of their appetite. Thirteen percent of day workers reported the best appetite but only 6.6% of shift workers had the best appetite. The gastric complaints is more frequent in shift workers than day workers(p<0.01). Among subscores in General Well-Being Schedule, anxiety, depression, positive well-being and vitality subscale of shift workers were lower than those of day workers(p<0.05) and general health and self control subscale of shift workers were lower than .those of day workers but there were no statistical significant difference. Based on these study result, it could be concluded that the shift work has significant effects on some psychophysiological conditions of the workers.

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Temporal Variations of Cerebrovascular Diseases in a University Hospital (일개 대학병원을 대상으로 한 뇌혈관질환의 시간적 변동양상)

  • Lee, Mi-Yon;Lee, Sang-Bock;Lee, Jun-Hang;Lee, Sam-Yul;Lee, Tae-Soo;Jin, Gye-Hwan
    • Journal of the Korean Society of Radiology
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    • v.1 no.1
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    • pp.17-23
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    • 2007
  • Background: Cerebrovascular diseases are known to show different patterns of incidence among regions and races. Therefore, it is very important to determine the incidence pattern of a specific area in order to diagnose, treat and prevent cerebrovascular diseases. The objective of the present study is to analyze quantitatively the incidence ratios of hemorrhagic and ischemic cerebrovascular diseases by season, by gender and by age. Methods: The subjects of this study were 1603 patients hospitalized for hemorrhagic or ischemic cerebrovascular diseases at the Department of Neurosurgery or the Department of Neurology of a University Hospital. Statistical analysis of data used Excel 2003 of Microsoft, and t-test was conducted using ORIGIN 6.0 of MICROCAL. Results: In the subjects, the incidence ratios of hemorrhagic and ischemic cerebrovascular diseases for four years, the period of this research, were 38.55% and 61.45%, respectively. The mean and standard deviation of age when hemorrhagic cerebrovascular diseases occurred were 58.20 and 12.60, respectively, and the percentages of subjects in their 40s, 50s, 60s and 70s were all around 20%. On the contrary, the mean and standard deviation of age when ischemic cerebrovascular diseases occurred were 65.01 and 13.59, respectively. The average age of patients with ischemic cerebrovascular diseases was older than that of patients with hemorrhagic brain diseases, and the percentages of those in their 60s, 70s and 80s were 15.53%, 37.06% and 27.72%, respectively. The season when hemorrhagic cerebrovascular diseases appeared most frequently was winter, which was followed by summer, spring and autumn. The season when hemorrhagic cerebrovascular diseases appeared most frequently was spring, which was followed by summer, winter and autumn. Conclusions: In this study, the incidence rates of hemorrhagic and ischemic cerebrovascular diseases were 38.55% and 61.45%, showing the rising percentage of ischemic cerebrovascular diseases. For making adequate prevention and disease control plans, it is considered necessary to make a long-term epidemiological investigation of cerebrovascular diseases.

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The Effects of Packed Red Blood Cell Washing and Circuit Precirculation-Ultrafiltration on the Production of Cytokines by Open Heart Surgery (충전용 농축적혈구의 세척 및 체외순환로의 전순환-초여과법이 개심수술에 의한 사이토카인 형성에 미치는 영향)

  • 전태국;노준량
    • Journal of Chest Surgery
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    • v.35 no.3
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    • pp.199-208
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    • 2002
  • Background: The washing of packed red blood cells could remove pro-inflammatory mediators, cell debris, and micro-particles contained in packed red blood cells, and the preci-rculation-ultrafiltration (recirculation and ultrafiltration of circuit itself before cardiopulmonary bypass) could attenuate the initial inflammatory reaction and remove the initial proinflam-matory mediators. This study was performed to evaluate whether the washing of packed red blood cells and precirculation-ultrafiltration can reduce the production of cytokines that have an important role in myocardial reperfusion injury. This study investigated the effects of washing the packed red blood cells and precirculation-ultrafiltration on the production of cytokines during and after cardiopulmonary bypass and open heart surgery. Material and Method: Forty eight infants with VSD undergoing open heart surgery under cardiopulmonary bypass were randomized into control group (group C, n=12), washing group (group W, n= 12), precirculation-ultrafiltration group (group F, n: 12), and combined group(washing and precirculation-ultrafiltration, group WF, n=12). Blood samples were obtained before, during, and after the bypass to assess plasma level of tumor necrosis factor-$\alpha$(TNF-$\alpha$), interleukin-6(IL-6), and interleukin-8 (IL-8). Results: Expressions of TNF-$\alpha$ were significantly reduced in combined group (group WF) compared with group C, group W, and group F (p<0.05). Expression of IL-6 were significantly reduced in group W, group F, and group WF compared with group C (p<0.05), but similar among group W, group F, and group WF (p=0.053). Expression of IL-8 were reduced in group W and group WF compared with group C (p<0.05), but similar among group W, group F, and group WF (p=0.067). Conclusion: In conclusion, the washing of packed red blood cells and precirculation-ultrafiltration blunted the increase of TNF-$\alpha$ , IL-6, and IL-8 during and after open heart surgery with cardiopulmonary bypass. However, the clinical benefits of these treatments remains unproven.

Is $^{99m}Tc$-MDP Mammoscintigraphy Useful in Patients with Breast Mass Lesions? ($^{99m}Tc$-MDP 유방 스캔은 유방 종괴의 감별진단에 임상적인 유용성이 있는가?)

  • Park, Seok-Gun;Lee, Yeon-Hee;Rhyu, Jin-Woo;You, Sun-Mee
    • The Korean Journal of Nuclear Medicine
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    • v.32 no.2
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    • pp.151-160
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    • 1998
  • Purpose: Piccolo et al. advocated the usefulness of $^{99m}Tc$-MDP breast scan in differential diagnosis of breast mass with high accuracy. But there are little or no follow-up studies about it as we know. We studied $^{99m}Tc$-MDP uptake pattern and lesion/background ratio in patients complaining palpable breast lesions to evaluate the clinical usefulness of $^{99m}Tc$-MDP scan. Materials and Methods: Total 34 patients were studied with physical examination, mammo-gram and $^{99m}Tc$-MDP scan prospectively. Anteroposterior and both lateral view of breast were obtained 5 minutes after iv injection of 740 MBq $^{99m}Tc$-MDP. Breast uptake pattern of $^{99m}Tc$-MDP was analyzed by a grade system: 0=no uptake, grade 1=bilateral diffuse uptake, grade 2=asymmetric faint uptake, grade 3=focal hot uptake. 20 cases were pathologically confirmed by excision biopsy or aspiration biopsy. 14 cases were normal in physical examination and mammogram. Results: Pathologic results showed 7 carcinomas, 6 benign solid tumors, and 7 fibrocystic changes. Grade 3 pattern of $^{99m}Tc$-MDP uptake was noted in 4/7 carcinomas, 3/6 benign solid tumors, and 1/7 fibrocystic changes. Grade 2 pattern was 217, 0/7, 3/7 respectively. The average L/B ratio was 1.66 in carcinomas, 1.68 in benign solid masses, 1.20 in fibrocystic diseases, 1.05 in normal patients. L/B ratio was higher in carcinoma and benign mass groups than in fibrocystic change and normal control groups(p=0.005). But there was no statistical difference between L/B ratio of malignant mass group and benign mass group. Conclusion: $^{99m}Tc$-MDP scan is not suitable to routine clinical use for breast mass diagnosis. It might be used in limited conditions when whole body bone scan is planned.

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Effects of Potassium-Channel Opener on Thallium-201 Kinetics: In-vitro Study in Rat Myocyte Preparations and In-vivo Mice Biodistribution Study (K-통로개방제가 배양심근세포와 생쥐 체내의 Thallium-201역동학에 미치는 영향)

  • Lee, Jae-Tae;Kim, Eun-Ji;Ahn, Byeong-Cheol;Sohn, Kang-Kyun;Lee, Kyu-Bo;Ha, Jeoung-Hee;Kim, Chun-K.
    • The Korean Journal of Nuclear Medicine
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    • v.30 no.4
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    • pp.507-515
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    • 1996
  • Background : Potassium channel opener (K-opener) opens ATP-sensitive K'-channel located at cell membrane and induces potassium efflux from cytosol, resulting in intracellular hyperpolarization. Newly synthesized K-opener is currently examined for pharmacologic potency by means of rubidium release test from smooth muscle strip pre-incubated with Rb-86. Since in-vivo behavior of thallium is similar to that of rubidium, we hypothesized that K-opener can alter T1-201 kinetics in vivo. Purpose : This study was prepared to investigate the effects of pinacidil (one of potent K-openers) on the T1-201 uptake and clearance in cultured myocyte, and in-vivo biodistribution in mice. Methods : Spontaneous contracting myocytes were prepared to imitate in-vivo condition from 20 hearts of 3-5 days old Sprague-Dawley rat and cultured for 3-5 days before use ($5{\times}10^5$ cells/ml). Pinacidil was dissolved in 10% DMSO solution at a final concentration of 100nM or l0uM and was co-incubated with T1-201 in HBSS buffer for 20-min to evaluate its effect on cellular T1-uptake, or challenged to cell preparation pre-incubated with T1-201 for washout study. Two, 40 or $100{\mu}g$ of pinacidil was injected intravenously into ICR mice at 10 min after $5{\mu}Ci$ T1-201 injection, and organ uptake and whole body retention rate were measured at different time points. Results : Co-incubation of pinacidil with T1-201 resulted in a decrease in T1-201 uptake into cultured myocyte by 1.6 to 2.5 times, depending on pinacidil concentration and activity of T1-201 used. Pinacidil enhanced T1-201 washout by 1.6-3.1 times from myocyte preparations pre-incubated with T1-201. Pinacidil treatment appears to be resulted in mild decreases in blood and liver activity in normal mice, in contrast, renal and cardiac uptake were mildly decreased in a dose dependent manner. Whole body retention ratios of T1-201 were lower at 24 hour after injection with $100{\mu}g$ of pinacidil than control. Conclusion : These results suggest that treatment with K-opener may affect the interpretation of T1-201 myocardial images, due to decreasing thallium accumulation and enhancing washout from myocardium.

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Serum Lmmunoglobulin G and M Level after Xenograft Valve or Valved Conduit Implantation (이종 조직판막 도관 혹은 판막 이식술 직후 면역 글로불린 항체 G, M의 혈중 농도 변화)

  • Kwak, Jae-Gun;Yoo, Jae-Suk;Yoon, Sun-Hee;Kim, Woong-Han;Kim, Kyung-Hwan;Kim, Yong-Jin
    • Journal of Chest Surgery
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    • v.41 no.2
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    • pp.223-228
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    • 2008
  • Background: The aim of this study is to confirm that peripheral blood sampling for measuring of serum immunoglobulin can predict immunological changes after xenograft implantation. Material and Method: Between March 2006 and January 2007, 19 patients were enrolled (10 xenograft implantation group, 9 control group). Through 3 peripheral blood samples, we measured changes in serum immunoglobulin G and M levels preoperatively, and 2 and 10 days postoperatively. Result: In both groups, serum immunoglobulin levels showed similar changes-they decreased 2 days postoperatively, then increased up to the baseline levels 10 days postoperatively. However, this postoperative change of immunoglobulin G and M was not significantly different in absolute value or pattern between the 2 groups (Ig G; p-value=0.393, Ig M; p-value=0.193). Conclusion: We could not predict immunological changes after xenograft implantation by measuring serum immunoglobulin levels by simple blood sampling. Direct checking of ${\alpha}$-Galactose antibody may confirm an immunological reaction after xenograft implantation.

Introduction of Stay Green Mutant for the Development of Black Seed Coat and Green Cotyledon Soybean Variety (녹색자엽 검정콩 품종 육성을 위한 Stay green 변이체 활용)

  • Kang, Sung-Taeg;Seo, Min-Jung;Moon, Jung-Kyeong;Yun, Hong-Tae;Lee, Young-Ho;Kim, Si-Ju;Hwang, Young-Sun;Lee, Suk-Ki;Choung, Myoung-Gun
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.55 no.3
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    • pp.187-194
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    • 2010
  • The soybean stay green mutant genotype (SSG) derived from the nuclear gene, d1d2, and cytoplasmic gene, cytG, inhibit the breakdown of chloroplast in the leaves, pod walls, seed coats, and embryos during maturity. Soybean seed with black seed coat and green cotyledon (SBG) are preferred than black seed coat with yellow cotyledon (SBY) especially for cooking with rice and as source of traditional food in Korea. The researchers evaluated the seed's chlorophyll content of SSG and introduced SSG to the SBG variety breeding program. The seed chlorophyll content of SSG with d1d2 was $39.93{\sim}60.80\;{\mu}g/g$ and SSG with cytG $38.08{\sim}39.89\;{\mu}g/g$. The Korean SBG variety which was derived from SSG with cytG, contains $16.35{\sim}37.73\;{\mu}g/g$. The composition of seed chlorophyll differs according to the genetic background of SSG genotype. Inheritance study showed that cotyledon color was segregated 15:1 (yellow:green) at $F_2$ seed indicating two recessive genes control green cotyledon as revealed by previous study. Only less than 3% soybean lines showed black seed coat with green cotyledon among crosses SBY and SSG (d1d2). Results showed that SSG with d1d2 can be used as a good source for SBG with high chlorophyll content in the seed cotyledon, but due to the complex genetic behavior, breeding resource of SBG with d1d2 should be prepared to improve the breeding efficiency for development SBG variety.

Residual Characteristics of Bistrifluron and Chlorantraniliprole in Strawberry (Fragaria ananassa Duch.) for Establishing Pre-Harvest Residue Limit (생산단계 잔류허용기준 설정을 위한 딸기 중 bistrifluron과 chlorantraniliprole의 잔류 특성 연구)

  • Lee, Jae Won;Kim, Ji Yoon;Kim, Hee gon;Hur, Kyung Jin;Kwon, Chan Hyeok;Hur, Jang Hyun
    • Korean Journal of Environmental Agriculture
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    • v.36 no.1
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    • pp.57-62
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    • 2017
  • BACKGROUND: Pesticide residue analysis is essentially required for safety evaluation of agricultural products. Bistrifluron and chlorantraniliprole have been currently considered as potentials to deeply evaluate their residues in agricultural products because they are frequently found in strawberry. This work was performed to investigate the residual patterns of bistrifluron and chlorantraniliprole in strawberry after harvest. METHODS AND RESULTS: Strawberry was treated with bistrifluron and chlorantraniliprole 0, 1, 2, 3, 5, 7 and 10 days before harvest under greenhouse conditions. The strawberry samples were subjected to solvent and solid phase extractions followed by LC-MS/MS analysis. There covery percentages of bistrifluron and chlorantraniliprole for tified in the control samples ranged from approximately 82 to 103% with the method limit of 0.005 mg/kg. The concentrations of bistrifluron and chlorantraniliprole in strawberry samples decreased significantly in 10 days after treatment, giving the safety levels of 0.04 to 0.06 mg/kg at 10 days after application, as considered maximum residue limit. The half-lives of bistrifluron and chlorantraniliprole based on first order kinetics were determined to 6.3 days and 6.4 days, respectively. CONCLUSION: Bistrifluron and chlorantraniliprole are suggested to use in strawberry 10 days before harvest to reach residual safety levels.

A Clinical Review and Results of Treatment in Non-squamous Cell Tumor of the Maxilla (상악동에 발생한 비편평세포암의 임상양상 및 치료성적)

  • Kim Se-Heon;Kim Kwang-Moon;Choi Eun-Chang;Keum Ki-Chang;Koh Yoon-Woo;Hong Won-Pyo
    • Korean Journal of Head & Neck Oncology
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    • v.14 no.2
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    • pp.182-190
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    • 1998
  • Background: Most of the cancers of maxillary sinus are the squamous variety, but various histopathologic types of malignant tumor can occur in the maxillary sinus. These non-squamous cell tumors have quite different patterns of clinical behavior compared with squamous variety, such as invasive characters, route of metastasis, treatment modality, and so on. Objectives: The authors intend to establish the clinical characteristics and treatment modalities of non-squamous cell tumors of the maxillary sinus. Material and Methods: We experienced 16 cases of non-squamous cell tumors arisen from the maxillary sinus during the 10-year period from 1987 to 1996. We analyzed their clinical features, therapeutic modalities and results with review of literatures. Results: According to AJCC TNM system, 13 patients presented with $T_{1-2}$, 3 with $T_{3-}4$, Two patients were treated with surgery after radiotherapy, 3 patients with surgery after chemotherapy and radiotherapy, 4 patients with chemotherapy and radiotherpy, 5 patients with chemotherapy and radiotherapy after surgery. Conclusion: In cases of adenoid cystic carcinoma, adenocarcinoma and sarcoma, we believe that the best form of therapy is wide surgical excision. If there is microscopic evidence of disease at or close to the resection margin, postoperative radiation was used to achieve better local control. In cases of undifferentiated carcinoma, preoperative chemotherapy and radiation therapy showed improved outcomes.

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