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1.
The results of measurements of the local irradiation dose to the most highly irradiated sections of the body of a therapy provider — the skin on the fingers and palm and regions of the chest — are presented. The measurements were performed by the method of thermoluminescence dosimetry using highly sensitive TLD-500K detectors. It was established that even for the highest total activity of these sources (1221 MBq) and the longest period of work without the use of x-ray protective gloves the maximum dose (minus the natural background and take the account to the energy dependence of the sensitivity of the detector) to the provider is 0.18 ± 0.01 mGy (the large finger on the right hand was exposed to the highest irradiation level) and 0.01 ± 0.0004 mGy (the outer side of the palm of the left-hand was exposed to the lowest irradiation level), which does not present a radiation hazard even when working repeatedly with the sources. __________ Translated from Atomnaya énergiya, Vol. 103, No. 2, pp. 125–128, August, 2007.  相似文献   

2.
The results of a reconstruction of the individual accumulated absorbed dose of internal and external whole-body irradiation (from 1986 to 2000) for the residents in the village of Zabor'e in the Krasnogorsk rayon of Bryansk oblast – the most highly contaminated populated point in Russia as a result of the Chernobyl accident (4329 kBq/m2 137Cs) – are presented. The total individual accumulated absorbed dose is 50–490 mGy. For 18 of the 42 individuals examined, the dose exceeds 200 mGy. It is found that the protective countermeasure (elimination of the family milk cows) taken in 1986 was ineffective, since in 1987 the villagers began to reacquire family cows. Measures are proposed for limiting the consumption of local contaminated food products. The computational methodology adopted, based on questioning the population and assessing the running radiation conditions, is verified by comparing with data from individual EPR dosimetry on tooth enamel for some of the individuals examined (10 samples). The agreement with the EPR data is good.  相似文献   

3.
马文财  刘延彰  赵瑛 《辐射防护》2021,41(Z1):26-28
为了加强铀纯化转化生产过程中作业人员的β外照射防护,结合国内外辐射监测实践,研究了铀纯化转化生产工艺过程中辐射源项的特性及辐射防护措施。由于铀系中主要β发射体234Th(UX1)、234mPa(UX2+UZ)、214Bi和214Pb的存在,铀化合物中的β辐射强度相当可观。在无防护措施的情况下,尤其是在进行开放式检修作业时,作业人员眼晶体、手部和皮肤的β受照剂量可能超过规定限值。因此,除了关注γ外照射和吸入内照射防护外,对作业人员β外照射的防护应该引起足够的重视。  相似文献   

4.
The content of 131I in the thyroid gland of approximately 30000 residents of Kaluga oblast was measured in May 1986. The work was supported by calibration and verification of the measurement means and procedure. The data making it possible to evaluate the individual, average, median, and collective dose of internal irradiation of the thyroid gland in people of different ages in the populated points of the oblast are presented. The irradiation dose to the thyroid gland in children is much higher than for adults. It is found that the individual dose of internal irradiation to the thyroid gland is described by a nearly log-normal distribution. Some of the individuals examined have an individual dose which is several-fold higher than the average and median dose. This indicates the presence of groups with an elevated radiation risk; attention should be focused on this group first when medical-prophylactic and protective measures are taken. The data from Kaluga oblast, combined with similar results from Bryansk oblast and Belarus, have served as basis for reconstructing the individual absorbed irradiation dose to the thyroid gland and as dosimetric support of radiation-epidemiological studies using the case-monitoring procedure. Translated from Atomnaya énergiya, Vol. 105, No. 2, pp. 97–103, August, 2008.  相似文献   

5.
王亮  彭勇  刘怡  彭红芬 《辐射防护》2019,39(6):517-521
探讨医院级各部位CT扫描辐射剂量及成人CT检查诊断剂量水平。采集2018年2月—2019年1月本院在GE Light Speed 16 CT设备上进行诊断性CT检查的全部成年人共15 440例的CT检查数据,按照检查部位进行分类,统计各部位的容积剂量指数(CTDIvol)、剂量长度乘积(DLP)。使用SPSS 19统计软件分析CTDIvolDLP的四分位数并计算有效剂量(ED)。结果表明,各部位CTDIvol的诊断剂量参考水平(DRL)值为:颅脑87.75 mGy、肺部8.09 mGy、上下腹15.82 mGy、上下腹盆腔15.79 mGy;各部位DLP的诊断剂量参考水平(DRL)值为:颅脑1 053.03 mGy·cm、肺部245.19 mGy·cm、上下腹269.96 mGy·cm、上下腹盆腔835.20 mGy·cm。研究中发现肺部CTDIvolDLPDRL值(分别为8.09 mGy、245.19 mGy·cm)低于我国其他地区和其他国家的DRL值;60岁以下患者肺部CT检查CTDIvolDLPDRL值低于8.09 mGy、245.19 mGy·cm,60岁以上患者肺部CT检查CTDIvolDLPDRL值高于8.09 mGy、245.19 mGy·cm。通过研究可以确定医院级各部位CT检查辐射剂量及成人CT检查诊断剂量水平,能为优化CT检查扫描技术和监测辐射剂量提供基础。  相似文献   

6.
Measurements of the 134,137Cs content in the bodies of the residents of the most contaminated areas of Bryansk and Kaluga oblasts have been performed since 1986. Data which make it possible to evaluate the individual and average effective dose of internal irradiation have been obtained. The work has been supported by calibration and verification of the measurement means and methods. It has been established that the individual dose is described by a nearly log-normal distribution with a long “tail” at doses substantially above the average and median values. This indicates the existence of groups with an elevated radiation risk so that these groups should be treated first when preventative-medical and protective measures are taken. It is shown that for the most highly contaminated regions of Bryansk and Kaluga oblasts most of the effective dose of internal irradiation is formed over a period of 8–10 years after the accident. __________ Translated from Atomnaya énergiya, Vol. 103, No. 3, pp. 192–197, September, 2007.  相似文献   

7.
鼻咽癌放射治疗时野外组织器官剂量的研究   总被引:1,自引:0,他引:1  
本文借助非均匀组织等效似人体模型,模拟鼻咽癌放射治疗,研究了^60Coγ射线和电子直线加速器产生的6MVX射线对野外组织器官的受照剂量。结果表明,离照射野越近组织器官受照剂量越高,加眼晶体、垂体、甲状腺等,但睾丸的受照剂量明显高于腹部;^60Coγ射线照射时野外组织器官的剂量明显高于6MVX射线;^60Coγ射线照射时,在耳前野野外挡铅可使眼晶体、视网膜受照剂量下降20%,睾丸表面挡铅可使睾丸受照  相似文献   

8.
Information about the radiation conditions in the Moscow region in 1957–2005 is presented. It is shown that the total activity of the β-emitting radionuclides, 90Sr and 137Cs, in atmospheric air, fallout, and food products changes. These data are used to estimate the total individual irradiation dose to the public, which does not exceed 0.2 mSv/yr. This is much less than the dose limit (1 mSv/yr) established in NRB-99. It is concluded that the radiation conditions in the Moscow region are satisfactory in the period studied. __________ Translated from Atomnaya énergiya, Vol. 100, No. 3, pp. 225–231, March, 2006.  相似文献   

9.
采用昆明小鼠,小剂量X射线全身照射50mGy~250mGy,剂量率为12.5mGy/min。停照后不同时间处死动物,取出脾脏。用贴壁法分离脾巨噬细胞(Mφ)和淋巴细胞,检测受照后脾Mφ与受照的脾淋巴细胞功能变化的关系。结果表明,小剂量辐射可使脾Mφ功能增强,主要表现在75mGyX射线全身照射后,脾Mφ对脾淋巴细胞ConA(刀豆蛋白A)反应增强,IL-1(白细胞介素1)分泌增多,受照的脾Mφ只对受照的脾淋巴细胞增强其ConA反应,而对未受照的脾淋巴细胞无显著影响;未受照的脾Mφ也不能增强受照的脾淋巴细胞功能  相似文献   

10.
The absorption and photoluminescence of LiF crystals, irradiated by γ radiation from a stopped reactor and a wet repository, are studied and compared with the corresponding spectra obtained by irradiation with 60Co γ rays with known power. The contribution of neutron and γ radiation of the reactor to the formation of point and complex radiation defects is determined. The dose dependences of the optical bands are used to determine the intensity of the γ radiation from the reactor and the repository. __________ Translated from Atomnaya énergiya, Vol. 100, No. 5, pp. 388–393, May, 2006.  相似文献   

11.
小剂量辐射增强化疗药物的抑瘤作用及其机制   总被引:4,自引:0,他引:4  
在丝裂霉素C(MMC)或环磷酰胺(CP)腹腔注射前6h,给予荷有Lewis肺癌的C57BL/6小鼠75mGyX射线全身照射(WBI)。结果表明75mGyX射线全身照射可增强化疗药物的抑瘤作用,肿瘤生长速度明显减慢。同时对与肿瘤免疫相关的某些免疫学指标进行了观察,发现75mGyX射线全身照射可以促进荷瘤鼠的胸腺和脾细胞的增殖,促进自然杀伤细胞(NK)、淋巴因子激活的杀伤细胞(LAK)和特异性杀伤性T细胞(CTL)的杀伤功能,增加脾细胞白细胞介素I(IL-2)的分泌量,并且减低MMC和CP对免疫功能的损害。  相似文献   

12.
孟庆勇  蔡露  金玉珂 《辐射防护》2002,22(4):212-218
采用低剂量X射线(剂量10和50mGy,剂量率50mGy/min)和低浓度丝裂霉素C(MitomycinC,MMC)、过氧化氢(Hydrogen peroxide,H2O2)、环磷酰胺(Cyclophoshamide,CP)交叉作用,观察了它们诱导的离体人血淋巴细胞、整体小鼠骨髓细胞和生殖细胞染色体畸变,以探讨辐射与化学物质之间的交叉适应性反应。结果表明:(1)预先给予10mGy的X射线照射,3h后予以不同浓度的MMC(0.5、2.5、5.0mg/kg),可诱导小鼠骨髓细胞染色体畸变的交叉适应性反应;(2)预先给予50mGy的X射线照射,3h后邓以不同浓度的MMC、H2O2、CP,其中,辐射与MMC和H2O2之间可诱导小鼠生殖细胞染色体畸变的交叉适应性反应,而辐射与CP之间未观察到交叉适应性反应,二者有协同作用;(3)预先给予MMC(终浓度为35ng/mL)处理,6h后给予1.5GyX射线照射,可诱导人血淋巴细胞染色体畸变的交叉适应性反应;(4)预先给予低浓度MMC、H2O2和CP处理,24h后给予1.5Gy射线照射,低浓度MMC和H2O2可以诱导抗X射线损伤的交叉适应性反应,而低浓度的CP不能诱导抗X射线损伤的交叉适应性反应,二者具有协同作用。提示X射线与MMC之间的交叉适应性反应不仅存在于整体的小鼠骨髓细胞中,而且在离体人外周血淋巴细胞中也可以诱生;低剂量X射线与低浓度MMC和H2O2之间的交叉适应性反应在整体的小鼠生殖细胞中可以互相诱导,但是,低剂量X射线与低浓度CP在整体的小鼠生殖细胞中未诱导出交叉适应性反应,二者有协同作用。  相似文献   

13.
采用放射性配体结合法,观察了不同低剂量X射线全身照射对小鼠脾细胞糖皮质激素受体(GCR)表达的影响及75mGy全身照射后GCR表达的时程变化。结果显示,25、50、75mGyX射线全身照射后8h小鼠脾细胞GCR表达明显下降;75mGyX射线全身照射后4hGCR表达开始下降,8hGCR表达显著低于对照组。低剂量X射线全身照射可降低小鼠脾细胞GCR的表达,提示GCR表达下调可能在低剂量辐射免疫增强效应  相似文献   

14.
The absorption spectra of unirradiated and irradiated (to fast neutron fluence 1012 and1014 cm−2 in VVR-SM) quartz-quartz fibers after additional irradiation with 60Co γ rays to 108 rad are investigated. It is shown that neutrons transform E′ centers into ≡Si-Si≡ centers. The kinetics of accumulation of bridge oxygen atoms under the action of γ radiation exhibits two stages. The first stage is due to neutron irradiation and the manifestation of preliminary potential centers of nonbridge oxygen atoms. The second stage is associated with the creation of additional nonbridge oxygen atoms under the action of γ radiation. The γ-ray dose for the onset of the second stage decreases as the fluence of the preliminary neutron irradiation increases. __________ Translated from Atomnaya énergiya, Vol. 104, No. 1, pp. 23–26, January, 2008.  相似文献   

15.
为探究低剂量α粒子辐照对斑马鱼初级造血的影响,使用241Am作为α粒子辐照源,对脱绒毛膜后的5 hpf胚胎进行0、0.425、0.85、1.7 mGy的辐照,采用整体原位杂交技术检测了约14 hpf斑马鱼胚胎初级造血分子标记物gata1a和spi1b的表达,采用实时荧光定量PCR技术检测了22 hpf斑马鱼胚胎初级造血分子标记物gata1a和spi1b的相对表达,并采用联大茴香胺染色法检测了48 hpf血红蛋白含量的变化。通过与对照组相比发现,0.425 mGy剂量组的gata1a表达无显著性差异(p>0.05),spi1b表达略有减少(p<0.05),血红蛋白含量显著减少;0.85 mGy剂量组的gata1a和spi1b表达均显著降低(p<0.01),血红蛋白含量明显减少;1.7 mGy剂量组的gata1a和spi1b表达均显著升高(p<0.001),血红蛋白含量显著增加。以上结果表明,剂量小于0.85 mGy的α粒子辐照对初级造血产生了抑制作用,而剂量为1.7 mGy的α粒子辐照诱导了胚胎兴奋效应,即剂量为1.7 mGy 的α粒子辐照对胚胎期斑马鱼初级造血具有促进作用。  相似文献   

16.
崔磊  郭丽莉  尹玉吉  王宏伟  王贵超  顾俊  祝军 《同位素》2021,34(1):1-9,I0001
2020年新型冠状病毒疫情在全世界爆发,在短期内需要大量一次性医用防护服,其中防护服的灭菌工艺是一个重要环节。医用一次性防护服若采用传统的环氧乙烷灭菌工艺需要至少7~14 d时间。γ辐照技术是一种可以对医用一次性防护服实施快速消毒灭菌的方法。因此,开展医用一次性防护服的辐照灭菌工艺研究有重要意义。选取两种典型的PET(聚对苯二甲酸乙二醇酯)材料的医用一次性防护服,一种有PU(聚氨酯)涂层,一种没有PU涂层。参考《医用一次性防护服辐照灭菌应急规范(临时)》和ISO 11137,分别进行生物负载实验。根据实验结果选择合适的方法建立灭菌剂量。使用苏州中核华东辐照有限公司BFT Ⅴ型γ辐照装置进行灭菌剂量验证。验证结果为满足无菌保证水平(SAL=10-6)的有PU涂层的防护服灭菌剂量为30.6 kGy,没有PU涂层的防护服灭菌剂量为30.8 kGy。对PET材料医用一次性防护服样品分别使用20.0 kGy、30.0 kGy和50.0 kGy的剂量辐照处理,材料断裂强力没有发生显著变化,且符合国家标准GB 19082-2009的相关要求。研究结果表明,对于以PET为主材的医用一次性防护服建立的γ辐照灭菌工艺有效,无菌保证水平为(SAL=10-6),同时对一次性防护服的辐照灭菌应用提出一些建议。  相似文献   

17.
Mathematical simulation is used to estimate the possible radiation consequences of an accidental failure of the protective dam of the coolant reservoir at the Chernobyl nuclear power plant. The dynamics of the emptying of the reservoir and the escape of radionuclides is calculated. The additional contamination of bottom deposits in the Dnepr River, which can be caused by the accidental escape of radioactive substances from the coolant reservoir, is estimated. The additional dose load to the public is estimated taking account of the food chains. A single-step mathematical model, taking account of the contamination of the water and the bottom deposits, is constructed to study the fish food chain. It is established that for an accidental failure of the protective dam of the coolant reservoir of the nuclear power plant the dose to the public will not exceed 2.5·10−3 Sv in the first year after the failure. Therefore, the destruction of the protective dam of the coolant reservoir of the Chernobyl nuclear power plant, if it occurs, will not be a radiation accident, 2. figures, 1 table, 9 references. Translated from Atomnaya énergiya, Vol. 88, No. 4, pp. 303–307, April, 2000.  相似文献   

18.
Radiotherapy uses ionizing radiation to destroy tumor cells. The absorbed dose control in the target volume is realized through radiation sensors, such as Fricke dosimeters and radiochromic film, which permit to realize bi-dimensional evaluations at once and because of that, they will be used in this study as well. Among the several types of cancer suitable for ionizing radiation treatment, the Mycosis Fungoides, a lymphoma that spreads on the skin surface and depth, requires for its treatment total body irradiation by high-energy electrons. In this work the Fricke xylenol gel (FXG) was used in order to obtain information about the absorbed dose distribution induced by the electron interactions with the irradiated tissues and to control this type of treatment. FXG can be considered as an alternative dosimeter, since up to now only films have been used. FXG sample cuvettes, simulating two selected tomos (cranium and abdomen) of the Rando anthropomorphic phantom, were positioned along with radiochromic films for comparison. The phantom was subjected to Stanford total body irradiation using 6 MeV electrons. Tomographic images were acquired for both dosimeters and evaluated through horizontal and vertical profiles along the tomographic centers. These profiles were obtained through a Matlab routine developed for this purpose. From the obtained results, one could infer that, for a superficial and internal patient irradiation, the FXG dosimeter showed an absorbed dose distribution similar to the one of the film. These results can validate the FXG dosimeter as an alternative dosimeter for the Mycosis Fungoides treatment planning.  相似文献   

19.
为了解湖南省X射线摄影设备(DR)6种主要检查部位不同的投照方位所致受检者的剂量水平,采用典型抽样法,在省内选取967例受检者作为调查样本,对常用的几种投照类型所致受检者的剂量进行调查。结果表明,湖南省内X射线摄影设备(DR),在腰椎前后位投照(AP)、腰椎侧位投照(LAT)、骨盆前后位投照(AP)、髋关节前后位投照(AP)、胸部后前位投照(PA)、胸部侧位投照(LAT)、胸椎前后位投照(AP)、胸椎侧位投照(LAT)、头颅后前位投照(PA)、头颅侧位投照(LAT)等部位投照时,所致受检者剂量的典型值分别为3.9、5.7、2.5、3.8、0.3、0.7、1.3、3.0、 0.7和0.7 mGy。无自动曝光控制(AEC)时,DR在胸部PA、胸部LAT摄影时所致受检者的剂量的平均值分别为0.77 mGy和1.44 mGy,有AEC时,DR在胸部PA、胸部LAT摄影时所致受检者的剂量的平均值分别为0.27 mGy和0.56 mGy。湖南省X射线摄影设备(DR)6种主要检查部位不同的投照方位所致受检者的剂量低于GB 18871—2002《电离辐射防护与辐射源安全基本标准》给出的典型成年受检者X射线摄影的剂量指导水平。在一定程度上, AEC能优化受检者在X射线摄影检查中受到的辐射剂量。  相似文献   

20.
A methodology remediating zones of local radioactive contamination is presented. It is based on a classification of the zones taking account of the contribution of external and internal irradiation to the total dose load to the public. The criteria for identifying such loads and the steps required for their remediation are identified. A radiation-ecological validation of the decrease in the external irradiation dose to the public in zones of local radioactive contamination is given. __________ Translated from Atomnaya énergiya, Vol. 100, No. 2, pp. 125–134, February, 2006.  相似文献   

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