• Title/Summary/Keyword: 선량 감소

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Effects of Heat Treatment on the Antigenicity of Gamma-Irradiated Egg White Albumin (감마선 조사된 난백 알부민의 항원성에 미치는 가열의 영향)

  • 이주운;육홍선;조경환;김미리;김천제
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.5
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    • pp.848-853
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    • 2001
  • This research was conducted to study the effects on antigenicities (allergenicity) and structural changes of gamma-irradiated hen’s egg albumin (ovalbumin, OVA) by heating. Three groups of OVA solution (2.0 mg/mL) were prepared; 1) heat treatment; 2) irradiation after heating; 3) heating after irradiation. Samples were isothermally heated and/or irradiated at the absorption dose of 10 kGy. Competitive indirect ELISA was individually formatted with egg-allergic patients IgE (P-IgE), and mouse murine monoclonal IgG (M-IgG) and rabbit polyclonal IgG (R-IgG) for evaluating bindinhg abilities of antibodies to OVA in the sample solutions. Binding abilities of antibodies to thermally denatured OVA were changed : R-IgG to the sample treated with above 6$0^{\circ}C$, M-IgG to that above 7$0^{\circ}C$, and P-IgE to that above 8$0^{\circ}C$, respectively. P-IgE did not well recognize OVA heated at 8$0^{\circ}C$ and the above. However, binding abilities of M-IgG and R-IgG highly in creased. Significant differences of binding abilities were not observed in all samples with the combination of heat treatment and irradiation, regardless the order of the treatment. Turbidity of samples in creased both by heating and by irradiation, and the increase by irradiation was much higher than by heating. These results showed that allergenicity of OVA reduced by gamma irradiation was not affected by heating.

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Comparison of Heel Effect with Distance and Direction Change (거리와 방향 변화에 따른 힐이팩트 비교)

  • Kim, Hyung-Woo;Seok, Ji-Eun;Kang, Min-Yeong;Jo, Chan-Haeng;Jeon, Min-Cheol
    • Journal of the Korean Society of Radiology
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    • v.16 no.4
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    • pp.435-442
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    • 2022
  • The heel effect creates a density difference in the X-ray images because the intensity of the anode and cathode side of the X-ray tube is not equal. The purpose of this study is to evaluate the density difference due to the heel effect by rotating the step wedge by 180 degrees and then changing the distance. After fixing the tube voltage and tube current to 72 kVp and 10 mAs, the forward and reverse directions were taken using a step wedge. At this time, the distance (80 cm ~ 130 cm) was taken at 10 cm intervals, and the density value was measured by setting the region of interest for each step of the step wedge through the M6 program. First, the difference in intensity between the anode and the cathode was confirmed through the radiation exposure test. In addition, when the distance (from 80 cm to 130 cm) was changed, the difference in density between the cathode and the anode decreased as the projection distance increased. As a result, images of uniform density can be obtained as the projection distance increases.

Studies on the Relationship between Radiosensitivity and Mutation Induction in Soybean (대두의 방사선감수성과 돌연변이 출현양상에 관한 연구)

  • Kwon, S.H.;Won, J.L.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.26 no.4
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    • pp.318-323
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    • 1981
  • This study was conducted to establish an effective radiation treatment and selection method for induced mutants in M_1 population of soybean treated with gamma-ray. About 64% of total M_1 plants was reduced in plant height up to 50 - 60% and among which 60 - 70% of the plants were contained mutations in M_2 generation. About 60% of the MI plants have born 6 - 15 seeds per plant and 50 - 60% of their progenies produced mutants in M_2 generation. Positive correlation between plant height and number of seeds per plant in M_1 population was found. Higher visible macro-mutation rate in M_2 was observed in the groups of reduced plant height and seed number in the M_1 generation, whereas the frequency of chlorophyll mutation was increased in the group of less damaged plants. The size of mutation sector was increased with reduction in number of seeds per M_1 plant and the mutants were occurred at random in all the parts of M_1 plants. For the effective selection of mutants in soybean mutation breeding, the M_1 seeds should be harvested from the radiation damaged M_1 plants with the application of higher doses of mutagens, and handling M_2 generation by bulk population method is recommendable.

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Adaptation of Deep Learning Image Reconstruction for Pediatric Head CT: A Focus on the Image Quality (소아용 두부 컴퓨터단층촬영에서 딥러닝 영상 재구성 적용: 영상 품질에 대한 고찰)

  • Nim Lee;Hyun-Hae Cho;So Mi Lee;Sun Kyoung You
    • Journal of the Korean Society of Radiology
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    • v.84 no.1
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    • pp.240-252
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    • 2023
  • Purpose To assess the effect of deep learning image reconstruction (DLIR) for head CT in pediatric patients. Materials and Methods We collected 126 pediatric head CT images, which were reconstructed using filtered back projection, iterative reconstruction using adaptive statistical iterative reconstruction (ASiR)-V, and all three levels of DLIR (TrueFidelity; GE Healthcare). Each image set group was divided into four subgroups according to the patients' ages. Clinical and dose-related data were reviewed. Quantitative parameters, including the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), and qualitative parameters, including noise, gray matter-white matter (GM-WM) differentiation, sharpness, artifact, acceptability, and unfamiliar texture change were evaluated and compared. Results The SNR and CNR of each level in each age group increased among strength levels of DLIR. High-level DLIR showed a significantly improved SNR and CNR (p < 0.05). Sequential reduction of noise, improvement of GM-WM differentiation, and improvement of sharpness was noted among strength levels of DLIR. Those of high-level DLIR showed a similar value as that with ASiR-V. Artifact and acceptability did not show a significant difference among the adapted levels of DLIR. Conclusion Adaptation of high-level DLIR for the pediatric head CT can significantly reduce image noise. Modification is needed while processing artifacts.

Combined Chemotherapy and Radiation Therapy in Limited Disease Small-Cell Lung Cancer (국한성 소세포 폐암에서 항암 화학 및 흉부 방사선치료의 병합요법 적응)

  • Kim Moon Kyung;Ahn Yong Chan;Park Keunchil;Lim Do Hoon;Huh Seung Jae;Kim Dae Yong;Shin Kyung Hwan;Lee Kyu Chan;Kwon O Jung
    • Radiation Oncology Journal
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    • v.17 no.1
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    • pp.9-15
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    • 1999
  • Purpose : This is a retrospective study to evaluate the response rate, acute toxicity, and survival rate of a combined chemotherapy and radiation therapy in limited disease small cell lung cancer, Materials and Methods : Firty-six patients with limited disease small-cell lung cancer who underwent combined chemotherapy and radiation therapy between October 1994 and April 1998 were evaluated. Six cycles of chemotherapy were planned either using a VIP regimen etoposide, ifosfamide, and cis-platin) or a EP regimen (etoposide and cis-platin). Thoracic radiation therapy was planned to deli- ver 44 Gy using 1 OMV X-ray, starting concurrently with chemotherapy. Response was evaluated 4 weeks after the completion of the planned chemotherapy and radiation therapy, and the prophylaetic cranial irradiation was planned only for the patients with complete responses. Acute toxicity was evaluated using the SWOG toxicity criteria, and the overall survival and disease-free survival were calculated using the Kaplan-Meier Method. Results : The median follow-up period was 16 months (range:2 to 41 months). Complete response was achieved En 30 (65$\%$) patients, of which 22 patients received prophylactic cranial irradiations. Acute toxicities over grade III were granulocytopenia in 23 (50$\%$), anemia in 17 (37$\%$), thrombo- cytopenia in nine (20$\%$), alopecia in nine (20$\%$), nausea/vomiting in five (11$\%$), and peripheral neuropathy in one (2$\%$). Chemotherapy was delayed in one patient, and the chemotherapy doses were reduced in 58 (24$\%$) out of the total 246 cycles. No radiation esophagitis over grade 111 was observed, while interruption during radiation therapy for a mean of 8.3 days occurred in 21 patients. The local recurrences were observed in 8 patients and local progressions were in 6 patients, and the distant metastases in 17 patients. Among these, four patients had both the local relapse and the distant metastasis. Brain was the most common metastatic site (10 patients), followed by the liver as the next common site (4 patients). The overall and progression-free survival rates were 79$\%$ and 55$\%$ in 1 year, and 45'/) and 32% in 2 years, respectively, and the median survival was 23 months. Conclusion : Relatively satisfactory local control and suwival rates were achieved after the combined chemotherapy and radiation therapy with mild to moderate acute morbidities in limited disease small cell lung cancer.

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Low Dose Cisplatin as a Radiation Sensitizer in Management of Locally Advanced Scluamous Cell Carcinoma of the Uterine Cervix : Evaluation of Acute Toxicity and Early Response (국소 진행된 자궁경부암의 방사선치료와 저용량 cisplatin 항암요법 동시치료시 급성독성 밀 초기반응 평가)

  • Kim Hunjung;Cho Young Kap;Kim Chulsu;Kim Woo Chul;Lee Sukho;Loh J K
    • Radiation Oncology Journal
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    • v.17 no.2
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    • pp.113-119
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    • 1999
  • Purpose : To evaluate possible acute toxicity and early response of concurrent radiation therapy and low dose daily cisplatin as a radiosensitizer in patients with locally advanced uterine cervical carcinomas. Materials and Method : From December 1996 to January 1999, 38 previously untreated Patients with locally advanced squamous cell carcinoma of the uterine cervix (from stage IIB to stage IIIB) were treated at Inha University Hospital. All patients underwent standard pretreatment staging Procedures after the initial evaluation by gynecologists and radiation oncologists. Sixteen Patients with huge cervical mass (>4 cm) were submitted to the group treated with concurrent radiation therapy and low dose daily cisplatin while the remainder was treated with radiation therapy alone. Radiation therapy consisted of 4500 cGy external beam irradiation to whole pelvis (midline block after 3000 cGy), 900$\~$1000 cGy boost to involved parametrium, and high dose-rate intracavitary brachytherapy (a total dose of 3000$\~$3500 cGy/500 cGy per fraction to point A, twice per week). In the group treated with low dose cisplatin concurrently, 10 mg of daily intravenous cisplatin was given from the 1st day of radiation therapy to the 20th day of radiation therapy. Acute toxicity was measured according to expanded common toxicity criteria of the NCI (C) Clinical Trials. Early response data were analyzed at minimum 4 weeks' follow-up after completion of the treatment protocol. Results: Hematolgic toxici쇼 was more prominent in patients treated with radiation therapy and cisplatin. Six of 16 patients (37.5$\~$) treated with radiation therapy and cisplatin and one of 22 patients (4.5$\~$) treated with radiation therapy alone experienced grade 3 leukopenia. In Fisher's exact test, there was statistically significant difference between two groups regarding leukopenia (P=0.030). There was no apparent difference in the frequency of gastrointestinal and genitourinary toxicity between two groups (P=0.066). Three of 16 patients (18.7$\~$) treated with radiation therapy and cisplatin and two of 22 patients (9.1$\~$) treated with radiation therapy alone experienced more than 5 kg weight loss during the treatment. There was no statistically significant difference on weight loss between two groups (P=0.63). Two patients on each group were not evaluable for the early response because of incomplete treatment. The complete response rate at four weeks' follow-up was 80$\~$(16/20) for the radiation therapy alone group and 78$\~$ (11/14) for the radiation therapy and cisplatin group. There was no statistically significant difference in early response between two treatment groups (P=0.126). Conclusion : This study led to the conclusion that the hematologic toxicity from the treatment with concurrent radiation therapy and low dose daily cisplatin seems to be more prominent than that from the treatment of radiation therapy alone. There was no grade 4 hematologic toxicity or mortality in both groups. The hematologic toxicity in both treatment groups seems to be well managable modically. Since the risk factors were not balanced between two treatment groups, the direct comparison of early response of both groups was not possible. However, preliminary results regarding early response for patients with bulky cervical tumor mass treated with radiation therapy and low dose daily cisplatin was encouraging. Longer follow-up is necessary to evaluate the survival data. A phase III study is needed to evaluate the efficacy of concurrent daily low dose cisplatin with radiation therapy in bulky cervical cancer.

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The Efficacy of the Change in Belly Board Aperture Location by the Addition of Bladder Compression Device for Radiotherapy of Rectal Cancer (직장암 환자의 골반 방사선치료에서 벨리보드 하위 경계 위치 변화의 영향)

  • Yoon, Hong-In;Chung, Yoon-Sun;Kim, Joo-Ho;Park, Hyo-Kuk;Lee, Sang-Kyu;Kim, Young-Suk;Choi, Yun-Seon;Kim, Mi-Sun;Lee, Ha-Yoon;Chang, Jee-Suk;Cha, Hye-Jung;Seong, Jin-Sil;Keum, Ki-Chang;Koom, Woong-Sub
    • Radiation Oncology Journal
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    • v.28 no.4
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    • pp.231-237
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    • 2010
  • Purpose: We investigated the effect of location changes in the inferior border of the belly board (BB) aperture by adding a bladder compression device (BCD). Materials and Methods: We respectively reviewed data from 10 rectal cancer patients with a median age 64 years (range, 45~75) and who underwent computed tomography (CT) simulation with the use of BB to receive pelvic radiotherapy between May and September 2010. A CT simulation was again performed with the addition of BCD since small bowel (SB) within the irradiated volume limited boost irradiation of 5.4 Gy using the cone down technique after 45 Gy. The addition of BCD made the inferior border of BB move from symphysis pubis to the lumbosacral junction (LSJ). Results: Following the addition of BCD, the irradiated volumes of SB and the abdominopelvic cavity (APC) significantly decreased ($174.3{\pm}89.5mL$ vs. $373.3{\pm}145.0mL$, p=0.001, $1282.6{\pm}218.7mL$ vs. $1,571.9{\pm}158mL$, p<0.001, respectively). Bladder volume within the treated volume increased with BCD ($222.9{\pm}117.9mL$ vs. $153.7{\pm}95.5mL$, p<0.001). The ratio of irradiated bladder volume to APC volume with BCD ($33.5{\pm}14.7%$) increased considerably compared to patients without a BCD ($27.5{\pm}13.1%$) (p<0.001), and the ratio of irradiated SB to APC volume decreased significantly with BCD ($13.9{\pm}7.6%$ vs. $24.2{\pm}10.2%$, p<0.001). The ratios of the irradiated SB volume and irradiated bladder volume to APC volume negatively correlated (p=0.001). Conclusion: This study demonstrated that the addition of BCD, which made the inferior border of BB move up to the LSJ, increased the ratio of the bladder to APC volume and as a result, decreased the irradiated volume of SB.

Pre-operative Concurrent Chemoradiotherapy for Stage IlIA (N2) Non-Small Cell Lung Cancer (N2 병기 비소세포 폐암의 수술 전 동시화학방사선요법)

  • Lee, Kyu-Chan;Ahn, Yong-Chan;Park, Keunchil;Kim, Kwhan-Mien;Kim, Jhin-Gook;Shim, Young-Mog;Lim, Do-Hoon;Kim, Moon-Kyung;Shin, Kyung-Hwan;Kim, Dae-Yong;Huh, Seung-Jae;Rhee, Chong-Heon;Lee, Kyung-Soo
    • Radiation Oncology Journal
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    • v.17 no.2
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    • pp.100-107
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    • 1999
  • Purpose: This is to evaluate the acute complication, resection rate, and tumor down-staging after pre-operative concurrent chemoradiotherapy for stage IIIA (N2) non-small cell lung cancer. Materials and Methods Fifteen patients with non-small cell lung cancer were enrolled in this study from May 1997 to June 1998 in Samsung Medical Center. The median age of the patients was 61 (range, 45~67) years and male to female ratio was 12:3. Pathologic types were squamous cell carcinoma (11) and adenocarcinoma (4). Pre-operative clinical tumor stages were cT1 in 2 patients, cT2 in T2, and cT3 in 1 and all were N2. Ten patients were proved to be N2 with mediastinoscopic biopsy and five had clinically evident mediastinal Iymph node metastases on the chest CT scans. Pre-operative radiation therapy field included the primary tumor, the ipsilateral hilum, and the mediastinum. Total radiation dose was 45 Gy over 5 weeks with daily dose of 1.8 Gy. Pre-operative concurrent chemotherapy consisted of two cycles of intravenous cis-Platin (100 mg/m$^{2}$) on day 1 and oral Etoposide (50 mg/m$^{2}$/day) on days 1 through 14 with 4 weeks' interval. Surgery was followed after the pre-operative re-evaluation including chest CT scan in 3 weeks of the completion of the concurrent chemoradiotherapy if there was no evidence of disease progression. Results : Full dose radiation therapy was administered to all the 15 patients. Planned two cycles of chemotherapy was completed in 11 patients and one cycle was given to four. One treatment related death of acute respiratory distress syndrome occurred In 15 days of surgery. Hospital admission was required in three patients including one with radiation pneumonitis and two with neutropenic fever. Hematologic complications and other acute complications including esophagitis were tolerable. Resection rate was 92.3% (12/l3) in 13 patients excluding two patients who refused surgery. Pleural seeding was found in one patient after thoracotomy and tumor resection was not feasible. Post-operative tumor stagings were pT0 in 3 patients, pTl in 6, and pT2 in 3. Lymph node status findings were pN0 in 8 patients, pN1 in 1, and pN2 in 3. Pathologic tumor down-staging was 61.5% (8/13) including complete response in three patients ($23.7%). Tumor stage was unchanged in four patients (30.8%) and progression was in one (7.7%). Conclusions : Pre-operative concurrent chemoradiotherapy for Stage IIIA (N2) non-small cell lung cancer demonstrated satisfactory results with no increased severe acute complications. This treatment shceme deserves more patinet accrual with long-term follow-up.

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Active Inferential Processing During Comprehension in Poor Readers (미숙 독자들에 있어 이해 도중의 능동적 추리의 처리)

  • Zoh Myeong-Han;Ahn Jeung-Chan
    • Korean Journal of Cognitive Science
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    • v.17 no.2
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    • pp.75-102
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    • 2006
  • Three experiments were conducted using a verification task to examine good and poor readers' generation of causal inferences(with because sentences) and contrastive inferences(with although sentences). The unfamiliar, critical verification statement was either explicitly mentioned or was implied. In Experiment 1, both good and poor readers responded accurately to the critical statement, suggesting that both groups had the linguistic knowledge necessary to the required inferences. Differences were found, however, in the groups' verification latencies. Poor, but not good, readers responded faster to explicit than to implicit verification statements for both because and although sentences. In Experiment 2, poor readers were induced to generate causal inferences for the because experimental sentences by including fillers that were apparently counterfactual unless a causal inference was made. In Experiment 3, poor readers were induced to generate contrastive inferences for the although sentences by including fillers that could only be resolved by making a contrastive inference. Verification latencies for the critical statements showed that poor readers made causal inferences in Experiment 2 and contrastive inferences in Experiment 3 doting comprehension. These results were discussed in terms of context effect: Specific encoding operations performed on anomaly backgrounded in another passage would form part of the context that guides the ongoing activity in processing potentially relevant subsequent text.

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HW/SW Partitioning Techniques for Multi-Mode Multi-Task Embedded Applications (멀티모드 멀티태스크 임베디드 어플리케이션을 위한 HW/SW 분할 기법)

  • Kim, Young-Jun;Kim, Tae-Whan
    • Journal of KIISE:Computer Systems and Theory
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    • v.34 no.8
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    • pp.337-347
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    • 2007
  • An embedded system is called a multi-mode embedded system if it performs multiple applications by dynamically reconfiguring the system functionality. Further, the embedded system is called a multi-mode multi-task embedded system if it additionally supports multiple tasks to be executed in a mode. In this Paper, we address a HW/SW partitioning problem, that is, HW/SW partitioning of multi-mode multi-task embedded applications with timing constraints of tasks. The objective of the optimization problem is to find a minimal total system cost of allocation/mapping of processing resources to functional modules in tasks together with a schedule that satisfies the timing constraints. The key success of solving the problem is closely related to the degree of the amount of utilization of the potential parallelism among the executions of modules. However, due to an inherently excessively large search space of the parallelism, and to make the task of schedulabilty analysis easy, the prior HW/SW partitioning methods have not been able to fully exploit the potential parallel execution of modules. To overcome the limitation, we propose a set of comprehensive HW/SW partitioning techniques which solve the three subproblems of the partitioning problem simultaneously: (1) allocation of processing resources, (2) mapping the processing resources to the modules in tasks, and (3) determining an execution schedule of modules. Specifically, based on a precise measurement on the parallel execution and schedulability of modules, we develop a stepwise refinement partitioning technique for single-mode multi-task applications. The proposed techniques is then extended to solve the HW/SW partitioning problem of multi-mode multi-task applications. From experiments with a set of real-life applications, it is shown that the proposed techniques are able to reduce the implementation cost by 19.0% and 17.0% for single- and multi-mode multi-task applications over that by the conventional method, respectively.