• Title/Summary/Keyword: 선량 감소

Search Result 1,219, Processing Time 0.028 seconds

Effects of Gamma Irradiation on Antioxidant Properties and Physical Characteristics of Sargassum siliquastrum Water Extract (꽈배기 모자반 물 추출물의 항산화능과 물리적 특성에 대한 감마선 조사의 영향)

  • Kim, Ah-Ram;Song, Eu-Jin;Kim, Mi-Jung;Lee, So-Young;Kim, Koth-Bong-Woo-Ri;Kim, Jin-Hee;Kim, Seo-Jin;Hong, Yong-Ki;Park, Jin-Gyu;Kim, Jae-Hun;Lee, Ju-Woon;Byun, Myung-Woo;Ahn, Dong-Hyun
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.37 no.3
    • /
    • pp.357-361
    • /
    • 2008
  • In this study, the antioxidant properties and physical characteristics of irradiated Sargassum siliquastrum water extract were evaluated. Samples were irradiated with $Co^{60}{\gamma}$-ray at doses ranging from 3 to 20 kGy. They were then analyzed to investigate antioxidant properties, including total phenolic compound content and DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity. In addition, physical properties such as viscosity and color were evaluated. The results demonstrated that total phenolic compound content and DPPH radical scavenging activity were significantly improved (p<0.05) by irradiation. In terms of physical properties, viscosity and color were reduced in the irradiated extracts as compared to non-irradiated samples. In conclusion, gamma irradiation improved the antioxidant properties of Sargassum siliquastrum water extract, improving its original weak point as a natural antioxidant when applied in the food industry.

Analysis of Factors Influencing the Integrated Bolus Peak Timing in Contrast-Enhanced Brain Computed Tomographic Angiography (Computed Tomographic Angiography (CTA)의 검사 시 조영제 집적 정점시간에 영향을 미치는 특성 인자를 분석)

  • Son, Soon-Yong;Choi, Kwan-Woo;Jeong, Hoi-Woun;Jang, Seo-Goo;Jung, Jae-Yong;Yun, Jung-Soo;Kim, Ki-Won;Lee, Young-Ah;Son, Jin-Hyun;Min, Jung-Whan
    • Journal of radiological science and technology
    • /
    • v.39 no.1
    • /
    • pp.59-69
    • /
    • 2016
  • The objective of this study was to analyze the factors influencing integrated bolus peak timing in contrast-enhanced computed tomographic angiography (CTA) and to determine a method of calculating personal peak time. The optimal time was calculated by performing multiple linear regression analysis, after finding the influence factors through correlation analysis between integrated peak time of contrast medium and personal measured value by monitoring CTA scans. The radiation exposure dose in CTA was $716.53mGy{\cdot}cm$ and the radiation exposure dose in monitoring scan was 15.52 mGy (2 - 34 mGy). The results were statistically significant (p < .01). Regression analysis revealed, a -0.160 times decrease with a one-step increase in heart rate in male, and -0.004, -0.174, and 0.006 times decrease with one-step in DBP, heart rate, and blood sugar, respectively, in female. In a consistency test of peak time by calculating measured peak time and peak time by using the regression equation, the consistency was determined to be very high for male and female. This study could prevent unnecessary dose exposure by encouraging in clinic calculation of personal integrated peak time of contrast medium prior to examination.

Effects of Preoperative Radiotherapy for $T_2,\;T_3$ Distal Rectal Cancer ($T_2,\;T_3$ 하부직장암의 수술 전 방사선치료 효과)

  • Kang Ki Mun;Choi Byung Ock;Jang Hong Seok;Kang Young Nam;Chai Gyu Young;Choi Ihl Bohng
    • Radiation Oncology Journal
    • /
    • v.20 no.3
    • /
    • pp.215-220
    • /
    • 2002
  • Purpose : Preoperative radiotherapy has been used to induce tumor regression and allow complete resection of rectal cancer with a sphincter preservation surgery. This study was performed to determine the effectiveness of preoperative radiotherapy for $T_2,\;T_3$ distal rectal carcinoma. Materials and Methods : From November 1995 to June 1997, fifteen patients with invasive distal rectal cancer were treated with preoperative radiotherapy followed by sphincter preservation surgery. Classification by preoperative T stage consisted of 7 $T_2$ and 8 $T_3$ tumors. Radiation therapy was delivered with 6 MV and 15 MV linear accelerator, at 1.8 Gy fractions for 5 days per week. Total radiation doses were 45 Gy to 50.4 Gy (median : 50.4 Gy). Sphincter preservation surgery was peformed $4\~6$ weeks after the completion of radiotherapy. Median follow-up was 22 months (range : $16\~37\;months$). Results : One patient $(6.7\%)$ had a complete pathologic response. Comparing the stage at the diagnostic workup with the pathologic stage, tumor downstaging of T stages occurred in 11 of 15 patients $(73.3\%)$ and $N_1$ stages occurred in 2 of 5 patients $(40\%)$. No patient developed progressive disease undergoing treatment. Two patients suffered local recurrence at 7 and 20 months, and one a distant metastasis at 30 months. No grade 3 or 4 toxicity was observed. Conclusion : Our experience suggests that preoperative radiotherapy followed by sphincter preservation surgery is well tolerated, and can significantly reduce the tumor burden for $T_2\;T_3$ distal rectal cancer.

Resolution Evaluation of a Pinhole Collimator according to the Aperture Diameter using Micro Deluxe Phantom (Micro Deluxe Phantom을 통한 핀홀 콜리메이터 초점의 직경별 분해능 평가)

  • An, Byung Ho;Yeon, Joon Ho;Kim, Soo Young;Choi, Sung Wook
    • The Korean Journal of Nuclear Medicine Technology
    • /
    • v.19 no.1
    • /
    • pp.3-11
    • /
    • 2015
  • Purpose It is hard to obtain high quality images of knee and T.M joint because of a lot of soft tissues in the knee and T.M joint area. Most conventional system for high resolution scintigraphy was used by 4 mm aperture pinhole collimator. Performance comparison of high-resolution pinhole SPECT for Micro deluxe phantom using conventional system. the aim of this study is to evaluate performance of each aperture according to the diameter size and the usefulness of 24-hour delayed bone scintigraphy. Materials and Methods In this study 6 mm, 8 mm diameter pinhole collimators were mounted on Siemens E.CAM systems. In order to evaluate performance evaluation of each aperture and Micro Deluxe phantom was used for performance comparison of conventional SPECT system, Projection data were obtained with 9 degree increment per 30 second. Transverse images were reconstructed using dedicated OSEM algorithm with recovery of detector blurring. $^{99m}Tc-HDP$ source was used for 24-hour delayed bone scintigraphy. Results The knee joint images obtained with 24-hour delay were improved more than those obtained with 3-hour delay in our study. The 6 mm and 8 mm pinhole collimators FWHM have improved by 28% SNR and Uniformity have improved by 35%, Contrast has improved by 7% in 24-hour delayed knee joint image. While in 24-hour delayed T.M joint image of the 6 mm and 8 mm pinhole collimators FWHM have decreased by 60% SNR has decreased by 20% and Uniformity has decreased by 25%, Contrast has decreased significantly. Conclusion Pinhole collimators with 6 mm and 8 mm diameter could offer a superior performance for 24-hour delayed bone scintigraphy. The use of 24-hour delayed image provides additional benefits for pinhole scintigraphy of knee joint. Therefore, we expect that it is useful for precise diagnosis of knee joint and it is applicable to others joint imaging.

  • PDF

Effectiveness Evalution of 18F-FDG Auto Dispenser (RIID: Radiopharmaceutical Intelligent Dispenser) (18F-FDG 자동분주기 사용에 따른 유용성 평가)

  • Yoo, Moon-Gon;Moon, Jae-Seung;Kim, Su-Geun;Shin, Min-Yong;Kim, Seung-Chul;Lee, Tea-hun;An, Sung-Hyeun
    • The Korean Journal of Nuclear Medicine Technology
    • /
    • v.22 no.2
    • /
    • pp.79-83
    • /
    • 2018
  • Purpose $^{18}F-FDG$, which is commonly used in PET-CT examinations, is low in capacity and it is difficult to keep the amount of radioactivity busy when the specific activity is high, increasing the amount of space dose and radioactive contamination in the distribution room. Therefore, while evaluating the actual dose administered to patients during the manual dispense process, the medical institution intends to assess the usefulness of the auto dispenser by comparing the differences from the actual dose administered to the patient using the new automatic dispense. Materials and Methods From July 2016 to December 2016, 846 patients were manually administered by workers using $^{18}F-FDG$ and $^{18}F-FDG$ 906 patients were using auto dispenser from July 2017 to December 2017. Results Capacity administered to patients during the manual dispense averaged $35.41{\pm}27.79%$ compared to the recommended dose, and the auto dispenser process showed a small difference of $-2.15{\pm}3.99%$ compared to the recommended dose(p<0.05). Conclusion Working people did not have to touch radioactive medicines directly while they were busy in the auto dispenser, and because of the availability of other tasks far away, the time and distance to receive the exposure were also advantageous. It is believed that future use by many medical institutions will not only reduce the dose to patients but also help reduce the exposure dose to workers.

Induction Chemotherapy and Radiotherapy in Locally Advanced Non-Small Cell Lung Cancer (NSCLC) (국소 진행된 비소세포성 폐암에서 유도 화학요법 및 방사선치료)

  • Yun, Sang-Mo;Kim, Jae-Cheol;Park, In-Kyu
    • Radiation Oncology Journal
    • /
    • v.17 no.3
    • /
    • pp.195-202
    • /
    • 1999
  • Purpose : We peformed this study to evaluate the prognostic factors and the effect of induction chemotherapy in locally advanced non-small cell lung cancer (NSCLC). Materials and Methods : A retrospective analysis was done for 130 patients with locally advanced NSCLC treated with curative radiotherapy alone or induction chemo-radiotherapy from January 1986 to October 1996. Eighty-five patients were treated with radiotherapy alone, forty-five with induction chemotherapy and radiotherapy. Age, sex, performance status, histopathologic type, and stage were evenly distributed in both groups. The patients were treated with 6 MV or 10 MV X-ray. Conventional fractionation with daily fraction size 1$.8\~2.0$ Gy was done. Of the patients, 129 patients received total dose above 59.6 Gy ($56\~66$ Gy, median 60 Gy). Induction chemotherapy regimen were CAP (Cyclo-phosphamide, Adriamycin, Cisplatin) in 6 patients, MVP (Mitomycin, Vinblastine, Cisplatin) in 9 patients, MIC (Mitomycin, Ifosfamide Cisplatin) in 13 patients, and EP (Etoposide, Cisplatin) in 17 patients. Chemotherapy was done in $2\~5$ cycles (median 2). Results : Overall 1-, 2-, and 3-year survival rate (YSR) for all patients were $41.5\%,{\;}13.7\%,{\;}and{\;}7\%$, respectively (median survival time 11 months). According to treatment modality, median survival time, overall 1-, 2-, and 3-YSR were 9 months, $32.9\%,{\;}10.\5%,{\;}6\%$ for radiotherapy alone group, and 14 months, $57.8\%,{\;}20\%,{\;}7.6\%$ for induction chemotherapy group, respectively (f=0.0005). Complete response (CR) to overall treatments was $25\%$ (21/84) in radiotherapy alone and $40.5\%$ (17/42) in induction chemotherapy group (p=0.09). The Prognostic factors affecting overall survival were hemoglobin level (p=0.04), NSE (neuron-specific enolase) level (p=0.004), and respense to overall treatment(p=0.004). According to treatment modalities, NSE (neuron-specific enolase) (p=0.006) and response to overall treatment (p=0.003) were associated with overall survival in radiotherapy alone group, and response to overall treatment (p=0.007) in induction chemotherapy group. The failure Pattern analysis revealed no significant difference between treatment modalities. But, in patients with CR to overall treatment, distant metastasis were found in 11/19 patients with radiotherapy alone, and 3/13 patients with induction chemotherapy and radiotherapy (p=0.07). Locoregional failure patterns were not different between two groups (10/19 vs 6/13). Conclusion : Induction chemotherapy and radiotherapy achieved increased 2YSR compared to radiotherapy alone, At least in CR patients, there was decreased tendency in distant metastasis with induction chemotherapy. But, locoregional failures and long-term survival were not improved. Thus, there is need of more effort to increasing local control and further decreasing distant metastasis.

  • PDF

Long-Term Results of 2-Dimensional Radiation Therapy in Patients with Nasopharyngeal Cancer (이차원방사선치료를 시행한 코인두암 환자의 장기 추적 결과 및 예후인자 분석)

  • Lee, Nam-Kwon;Park, Young-Je;Yang, Dae-Sik;Yoon, Won-Sup;Lee, Suk;Kim, Chul-Yong
    • Radiation Oncology Journal
    • /
    • v.28 no.4
    • /
    • pp.193-204
    • /
    • 2010
  • Purpose: To analyze the treatment outcomes, complications, prognostic factors after a long-term follow-up of patients with nasopharyngeal carcinoma treated with radiation therapy (RT) alone or concurrent chemoradiation therapy (CCRT). Materials and Methods: Between December 1981 and December 2006, 190 eligible patients with non-metastatic nasopharyngeal carcinoma were treated at our department with a curative intent. Of these patients, 103 were treated with RT alone and 87 patients received CCRT. The median age was 49 years (range, 8~78 years). The distributions of clinical stage according to the AJCC 6th edition included I: 7 (3.6%), IIA: 8 (4.2%), IIB: 33 (17.4%), III: 82 (43.2%), IVA: 31 (16.3%), IVB: 29 (15.3%). The accumulated radiation doses to the primary tumor ranged from 66.6~87.0 Gy (median, 72 Gy). Treatment outcomes and prognostic factors were retrospectively analyzed. Acute and late toxicities were assessed using the RTOG criteria. Results: A total of 96.8% (184/190) of patients completed the planned treatment. With a mean follow-up of 73 months (range, 2~278 months; median, 52 months), 93 (48.9%) patients had relapses that were local 44 (23.2%), nodal 13 (6.8%), or distant 49 (25.8%). The 5- and 10-year overall survival (OS), disease-free survival (DFS), and disease-specific survival (DSS) rates were 55.6% and 44.5%, 54.8% and 51.3%, in addition to 65.3% and 57.4%, respectively. Multivariate analyses revealed that CCRT, age, gender, and stage were significant prognostic factors for OS. The CCRT and gender were independent prognostic factors for both DFS and DSS. There was no grade 4 or 5 acute toxicity, but grade 3 mucositis and hematologic toxicity were present in 42 patients (22.1%) and 18 patients (9.5%), respectively. During follow-up, grade 3 hearing loss in 9 patients and trismus in 6 patients were reported. Conclusion: The results of our study were in accordance with findings of previous studies and we confirmed that CCRT, low stage, female gender, and young age were related to improvement in OS. However, there are limitations in the locoregional control that can be achieved by CCRT with 20 conventional radiation therapy. This observation has led to further studies on clarifying the efficacy of concurrent chemotherapy by intensity modulated radiation therapy.

Twice Daily Radiation Therapy Plus Concurrent Chemotherapy for Limited-Stage Small Cell Lung Cancer (국한성병기 소세포폐암에서 하루 두 번 분할조사와 동시 화학방사선치료)

  • Yeo Seung-Gu;Cho Moon-June;Kim Sun-Young;Kim Ki-Whan;Kim Jun-Sang
    • Radiation Oncology Journal
    • /
    • v.24 no.2
    • /
    • pp.96-102
    • /
    • 2006
  • Purpose: A retrospective study was performed to evaluate the efficiency and feasibility of twice daily radiation therapy plus concurrent chemotherapy for limited-stage small cell lung cancer in terms of treatment response, survival, patterns of failure, and acute toxicities. Materials and Methods: Between February 1993 and October 2002, 76 patients of histologically proven limited-stage small cell lung cancer (LS-SCLC) were treated with twice daily radiation therapy and concurrent chemotherapy. Male was in 84% (64/76), and median age was 57 years (range, 32-75 years). Thoracic radiation therapy consisted of 120 or 150 cGy per fraction, twice a day at least 6 hours apart, 5 days a week. Median total dose was 50.4 Gy (range, 45-51 Gy). Concurrent chemotherapy consisted of CAV ($cytoxan\;1000mg/m^2,\;adriamycin\;40mg/m^2,\;vincristine\;1mg/m^2$) alternating with PE ($cisplatin\;60mg/m^2,\;etoposide\;100mg/m^2$) or PE alone, every 3 weeks. The median cycle of chemotherapy was six (range, 1-9 cycle). Prophylactic cranial irradiation (PCI) was recommended to the patients who achieved a complete response (CR). PCI scheme was 25 Gy/10 fractions. Median follow up was 18 months (range, 1-136 months). Results: Overall response rate was 86%; complete response in 39 (52%) and partial response in 26 (34%) patients. The median overall survival was 23 months. One, two, and three year overall survival rate was 72%, 50% and 30%, respectively. In univariate analysis, the treatment response was revealed as a significant favorable prognostic factor for survival (p<0.001). Grade 3 or worse acute toxicities were leukopenia in 46 (61%), anemia in 5 (6%), thrombocytopenia in 10 (13%), esophagitis in 5 (6%), and pulmonary toxicity in 2 (2%) patients. Of 73 evaluable patients, 40 (55%) patients subsequently had disease progression. The most frequent first site of distant metastasis was brain. Conclusion: Twice daily radiation therapy plus concurrent chemotherapy produced favorable response and survival for LS-SCLC patients with tolerable toxicities. To improve the treatment response, which proved as a significant prognostic factor for survival, there should be further investigations about fractionation scheme, chemotherapy regimens and compatible chemoradiotherapy schedule.

Evaluating The Radioprotective Effect of Avocado Peel Extracts upon Rat Exposed to 6 MV X-Ray (6 MV X-ray에 피폭된 흰쥐에 대한 아보카도 껍질 추출물의 방사선방호효과 평가)

  • Kim, Jang-Oh;Shin, Ji-Hye;Jung, Do-Young;Jeon, Chan-hee;Lee, Ji-Eun;Lee, Yoon-Ji;Min, Byung-In
    • Journal of the Korean Society of Radiology
    • /
    • v.14 no.5
    • /
    • pp.553-561
    • /
    • 2020
  • In this study aims to investigate the radiation protection effect of avocado peel extracts on the Sprague-Dawely rats. 52 male rats were randomly classified into 4 groups. NC Group was a normal control group, PA Group was a group injected avocado peel extracts, IR Group was irradiated group, and lastly PA+IR Group was set as an irradiated group after injected of avocado peel extracts. Avocado peel extract was administered orally at 200 mg/kg once a day for 14 days before irradiation, and the radiation dose was systemically irradiated with 6 MV X-ray of 7 Gy. On the 4 and 21 days after irradiation, the experimental animals were sacrificed to evaluate the change in blood cell composition, spleen index, and histopathological evaluation of the liver and small intestine. As a result, the PA+IR Group showed a significantly greater recovery of lymphocytes(p<0.01), red blood cells(p<0.01), and platelets(p<0.05) than the IR Group. It was also confirmed that the activation of Superoxide Dismutase(SOD) was further increased. Histopathologically, observed that nuclei aggregation and cytoplasmic expansion were slightly reduced in the PA+IR Group in the liver. and the damage was significantly reduce(p<0.01) in the change of villi length due to damage to the small intestine cells. Based on the above results, avocado peel extract can be expected to act as a radiation protection agent that can reduce damage to blood cells and major organs caused by irradiation.

Chungkook-jang Koji Fermentation with Rice Straw (볏짚을 이용(利用)한 청국장 제조(製造)에 관(關)한 연구(硏究))

  • Kim, Kyung-Ja;Ryu, Myung-Ki;Kim, Sang-Soon
    • Korean Journal of Food Science and Technology
    • /
    • v.14 no.4
    • /
    • pp.301-308
    • /
    • 1982
  • Chungkook-jang Koji was fermented with rice straw at $40^{\circ}C\;and\;50^{\circ}C$ for 72 hours. The changes of proximate composition, pH, titrable acidity, nitrogen compounds, protease activity and free-amino acids during the fermentation were investigated. Moisture, lipid and protein contents remained essentially unchanged during the fermentation. The pH was gradually increased from 6.4 to 7.46 and 7.82 at $40^{\circ}C\;and\;50^{\circ}C$, respectively, after 72 hour fermentation. Amino type and water soluble nitrogen increased as fermentation progressed. however, the former slightly decreased after 60 hour fermentation. Chungkook-jang fermented at $40^{\circ}C$ showed somewhat higher protease activity than $50^{\circ}C$. However, protease activity at both fermentation temperatures showed the same trend; that is, it increased until 48 hour fermentation and thereafter decrease. Free amino acid content of Chung-kook-jang after 72 hour fermentation at $40^{\circ}C$ was 6 times greater than that of the steamed soybean, while it was 2.5 times greater at $50^{\circ}C$. Based on these results. it seems that the optimum fermentation conditions for Chungkook-jang were $40^{\circ}C$ and 72 hours.

  • PDF