大面积照射及其相应的一次全身等效剂量的研究

本文主要应用红骨髓干细胞法来估算大面积、非均匀条件的照射剂量归一于全身均匀照射剂量,这样就可以利用日常的一些特殊照射来建立不同程度的造血型放射病模型。通过对各种不同的归一等效剂量的方法进行比较,认为干细胞法的估算与临床实际最为符合,是一种值得重视的估算等效剂量的方法。     

介入放射学照射剂量对患者淋巴细胞微核的影响

医疗照射是人工电离辐射主要来源。介入放射是医疗照射的重要组成部分。介入放射学是否造成患者遗传物质的损伤，目前这方面报道还较少，因此我们用人淋巴细胞微核为指标（ＣＢ法），检测介入放射学患者照射前后的双核微核变化，以判别患者的淋巴细胞遗传物质的损伤情况。...     

三例大面积放疗病人染色体畸变率、微核率检测及全身等效剂量估算

为探讨在高度不均匀照射条件下 ,以微核 (ＭＮ)率和双 环 (ｄｉｃ ｒ)率所估算的相当于一次全身均匀受照剂量 ,我们用常规ＣＡ分析和ＣＢＭＮ法对接受全淋巴区、全腹和下半身放疗的 3例晚期肿瘤病人进行了外周血淋巴细胞ＣＡ率和ＭＮ率检测 ,比较了以ｄｉｃ ｒ率和ＭＮ率所估算的相当于一次全身均匀受照剂量。并针对ＣＢＭＮ法用作辐射生物剂量计时 ,其相对偏高的本底对剂量估算的影响进行了探讨。一、材料和方法1 病人 :接受全淋巴区、全腹和下半身6 0 Ｃｏγ射线放疗的 3例男性晚期肿瘤病人 ,中心平面剂量分别为 8、6和 6Ｇｙ。2 血样…     

狗全身照射后淋巴细胞微核蜕减规律的探讨

狗全身照射后淋巴细胞微核蜕减规律的探讨蒋本荣，张海鹰，姚波淋巴细胞微核ＯＩ入）检测在核辐射事故受照者剂量估算中的重要性日益受到重视。国内一些学者相继以常规法及ＣＢ法建立了ＭＮ的剂量效应刻度曲线，用于临床，取得可喜的结果。由于射线诱发的ＭＮ主要源于染色...     

计算机在淋巴细胞微核作为放射损伤生物剂量计时的应用

放射事故后，尽快提供人员的受照剂量对及时的医学救援至关重要。该文用Ｃ语言给该实验室研制的各类淋巴细胞微核剂量效应刻度曲线估算剂量及其９５％可信区间的计算过程编制了一套计算机程序以代替繁琐的手算。经验证，本程序操作简便，结果可靠，计算速度快，对计算机在临床诊断效率方面的应用是一次有益的尝试，所叙述的编程技巧同样适用于其他类型实用程序的开发。     

不同LET射线及其联合照射下淋巴母细胞微核率的剂量效应

目的 探讨在α粒子、γ射线以及联合照射下淋巴母细胞微核率的剂量效应.方法 以HMy2.CIR淋巴母细胞为对象,分别以不同剂量的α粒子和γ射线进行照射,以及先以0.025 ～0.500 Gy的α粒子照射后即刻以不同剂量的γ射线进行照射,用胞质分裂阻断法检测淋巴细胞微核,建立不同照射条件下淋巴母细胞微核率的剂量-效应曲线.结果 对于γ射线照射,微核率剂量-效应符合线性平方模型Y=c+αD+ βD2.对于α粒子照射,当照射剂量＜0.250 Gy时,细胞微核率随剂量的增加呈线性增加,当其剂量进一步增加时,微核率剂量-效应曲线呈现下弓型,可以采用反映辐射旁效应的BaD模型Y=c +αD +σ[1 -exp(-δD)]exp(-βD)进行很好地拟合.对于联合照射,当α粒子剂量较低时,微核率的剂量效应与γ射线照射时的相似;但当α粒子剂量较大时,微核率的剂量-效应更接近于α粒子照射.同时,0.2、0.5 Gyα粒子联合γ射线照射引起的微核率显著高于它们单独照射时的微核率之和(=5.22 ～ 11.86,P＜0.05).结论 α粒子照射具有与γ射线不同的辐射损伤规律,辐射旁效应可能在其中发挥了重要作用,而联合照射则可以引起细胞损伤的协同增强.     

快中子照射离体血建立淋巴细胞微核的剂量效应曲线

十年来，国内外学者们用ＣＢ微核法研究了各种辐射类型诱发微核的剂量效应关系和影响因素，并建立了多条剂量效应曲线［１～４］。国内学者已报道多例用ＣＢ法估算生物剂量的结果［５～７］。本研究目的是用快中子照射离体血建立淋巴细胞微核的剂量效应曲线，以备用于中子...     

干细胞剂量在不均匀照射时应用的生物学依据探讨

事故照射全身剂量常为高度不均匀,骨髓型放射病的靶器官是分布于全身的红骨髓．因此,在不均匀照射时就有估计等效剂量的问题．     

A phantom experiment for the evaluation of whole body exposure during BNCT using cyclotron-based epithermal neutron source (C-BENS)

At Kyoto University Research Reactor Institute (KURRI), cyclotron-based epithermal neutron source was installed in December 2008, and the supplementary construction works have been performed. As of December 2010, the various irradiation characteristics important for BNCT were mostly evaluated. The whole body exposure during BNCT medical irradiation is one of the important characteristics.In this article, measurements of absorbed dose for thermal and fast neutrons and gamma-ray at ten positions corresponding to important organs are reported.     

Quantification of DNA damage in patients undergoing non-contrast and contrast enhanced whole body PET/CT investigations using comet assay and micronucleus assay

Abstract

Objective: To quantify DNA damage in patients undergoing non-contrast and contrast-enhanced ¹⁸F-FDG PET/CT whole body positron emission tomography/computed tomography (WB PET/CT) investigations using comet assay technique and micronucleus assay, and to study the effect of other baseline parameters of patients on DNA damage.

Methodology: Eighty-four patients referred for ¹⁸F-FDG PET/CT investigation were included in the study of which 44 patients underwent contrast-enhanced WB PET/CT and 40 patients underwent non-contrast WB PET/CT investigations. The investigations were performed on Discovery 690 PET/CT. For contrast-enhanced investigation, Omnipaque300 was injected intravenously based on the patient body weight. Absorbed dose resulting from the intravenous administration of ¹⁸F-FDG was estimated using the ICRP 106 dose coefficients. Radiation dose from the acquisition of CT scans was estimated using CT dose index and dose-length product. Blood samples were collected from the patients for DNA damage analysis. Comet assay and MN assay was used to assess the DNA damage. The Differences in the comet TM (Tail Moment) and MNBC % in both groups were calculated.

Result: The radiation dose received by the study population during ¹⁸F-FDG WB PET/CT examination was 27.03?±?2.33 mSv. Comet TM and percentage frequency of MNBC % was 65.22?±?35.42 and 18.55?±?10.14, respectively in the patients injected with contrast and 42.49?±?28.52 and 13.76?±?7.52 for non-contrast group. Significant increase in DNA damage was observed in the contrast group as compared to non-contrast group. Significant association was observed between patient weight, contrast volume and TM and MNBC%. Baseline parameters of the patients did not show significant correlation with TM and MNBC%.

Conclusion: The patients undergoing contrast-enhanced WB PET/CT investigations have demonstrated higher DNA damage. The DNA damage was also observed to be more in heavier patients. The other baseline parameters of patients like age, sex, CBG, serum creatinine did not show any correlation with DNA damage.     

Standardized assessment of whole body adipose tissue topography by MRI

PURPOSE: To assess standardized whole body adipose tissue topography in a cohort of subjects at an increased risk for type 2 diabetes and to compare fat distribution in subgroups regarding anthropometric (age, body mass index [BMI]) and metabolic parameters (insulin sensitivity). MATERIALS AND METHODS: A total of 80 volunteers (40 females, 40 males) underwent T1-weighted MR imaging of the entire body. Standardized adipose tissue (AT) profiles were calculated considering the different body structure of the participants. The measured data were interpolated to a defined number of sampling points enabling a direct comparison of the profiles independent on body structure. Resulting mean profiles and region-dependent standard deviations of four age groups and three BMI-groups were compared for females and males. Correlations between insulin sensitivity and body fat distribution were analyzed. RESULTS: Reliable adipose tissue profiles could be obtained from all volunteers. In BMI-matched subgroups, females show significant higher AT and subcutaneous abdominal AT (P < 0.05 both), but lower visceral AT (P < 0.01) compared to the males. Furthermore, visceral AT increases with age, as shown in the matched age groups. In both gender groups, insulin-resistant subjects are characterized by higher visceral adipose tissue (VAT) compared to insulin-sensitive subjects. In addition, profiles of insulin-resistant subjects show more AT in the shoulder/neck region but less AT in the upper extremities. CONCLUSION: Standardized assessment of whole body AT profiles based on T1-weighted MRI provides a reliable basis for interindividual comparison of the body fat distribution and allows a fast and reliable quantification of total body adipose tissue and the distribution of different AT components as subcutaneous and visceral fat in different body regions. Differences in standardized profiles might enable an early identification of people at risk of metabolic disorders, as not only the amount but also the distribution of AT is expected to play an essential role in the pathogenesis of metabolic diseases.     

手表红宝石事故剂量计在电离辐射事故剂量测量中的应用

研制了两种用于手表红宝石事故剂理计测量的特殊热释光剂量读出装置；对国内、外１０种不同种类、型号的手表红宝石热释光剂理特性进行了实验研究，结果表明：在热释发光曲线、灵敏度、重复使用性、衰退性、光敏性、能量响应、剂量响应等性能满足事故个人剂量测量的要求，手表红宝石是目前人体佩戴物中方便易得的实用个人事故剂量计；在几起辐射事故中得到了成功的应用，其中列举了一起有代表性的＾６０Ｃｏ源事故受照者的剂量测量和     

A semi-automated micronucleus-centromere assay to assess low-dose radiation exposure in human lymphocytes

Abstract

Purpose: The in vitro micronucleus (MN) assay is a reliable method to assess radiation-induced chromosomal damage in human peripheral blood lymphocytes. It is used to evaluate in vivo radiation over-exposure and to assess in vitro chromosomal radiosensitivity. A limitation of the MN assay is the relatively high and variable spontaneous MN frequency that restricts low-dose estimation to doses of about 0.3 gray (Gy). As radiation-induced MN mainly contain acentric fragments and spontaneous MN originate from lagging chromosomes, both MN types can be distinguished from each other by using fluorescence in situ hybridisation (FISH) with a pan-centromeric probe. The aim of this study was to investigate if the sensitivity, reliability and processing time of the MN assay can be enhanced by combining the automated MN assay with pan-centromere scoring.

Materials and methods: Blood samples from 10 healthy donors were irradiated in vitro with low doses of gamma-rays. Dose response curves were determined for fully-automated and semi-automated MN scoring and semi-automated scoring of centromere negative MN (MNCM?).

Results: A good correlation was obtained between fully-automated and semi-automated MN scoring (r² = 0.9973) and between fully automated MN scoring and semi-automated scoring of MNCM? (r² = 0.998). With the Wilcoxon test, a significant p value was obtained between 0 and 0.2 Gy for the fully-automated MN analysis, between 0 and 0.1 Gy for semi-automated MN analysis and between 0 and 0.05 Gy for semi-automated scoring of MNCM?.

Conclusion: The semi-automated micronucleus-centromere assay combines high-speed MN analysis with a more accurate assessment in the low-dose range which makes it of special interest for large-scale radiation applications.     

上海市1990～1994年放射工作人员外照射个人剂量水平与评价

作者提出了一种应用联合国原子辐射效应科学委员会１９８２年报告中推荐的放射工作人员个人剂量监测结果的几个参量［１］：个人年平均剂量当量、年集体剂量当量和个人剂量当量大于１５ｍＳｖ人员年集体剂量当量与总年集体剂量当量的比值ＭＲ１５的新方法。并以这种方法评价上海市放射工作人员外照射个人剂量水平。结果表明在１９９０～１９９４年期间上海市放射工作人员个人剂量［２］年平均剂量当量在０．４０～４．０４ｍＳｖ，低于国家标准所规定的剂量当量限值的十分之一（５ｍＳｖ），超过年剂量当量的十分之三（１５ｍＳｖ）有１１６人次，ＭＲ１５在０．０１～０．４９。有３２８人次超调查水平（月剂量当量限值１．２０ｍＳｖ）．对超调查水平者进行随访调查。针对＂真实＂、＂虚假＂者进行详细分析，并为有关放射工作单位提出相应的改进意见和个人防护措施。并指出今后搞好放射防护和个人剂量监测的关键［３］。     

FOLFOX4化疗联合全身热疗治疗晚期大肠癌的临床观察

目的观察FOLFOX4方案化疗联合太空舱全身热疗治疗晚期直肠癌的近期疗效及安全性。方法将2008年1月—2010年12月收治的38例晚期结、直肠癌患者,分为两组,观察组20例在深度镇静下行FOLFOX4方案化疗联合太空舱全身热疗仪进行全身热化疗,对照组18例采用FOLFOX4方案进行化疗。结果观察组有效率(RR)60.0%,疾病控制率(DCR)80.0%;对照组RR 27.8%,DCR 44.4%。两组间RR、DCR比较差异均有统计学意义(P<0.05)。观察组与对照组的主要化疗毒副反应为骨髓抑制及恶心、呕吐等,两组间比较差异无统计学意义(P>0.05)。观察组中出现Ⅰ～Ⅱ度皮肤烧伤4例,无一例出现急性心肺功能衰竭。结论采用太空舱全身热疗系统联合FOLFOX4方案进行全身热化疗治疗晚期结、直肠癌安全有效。     

A trial of semiquantitative analysis of whole body bone scintigraphy in renal osteodystrophy

Four color processed whole body bone scintigraphy with ^99mTc-methylene diphosphonate was performed in six patients on maintenance hemodialysis, and the results of semiquantitative colorimetric analysis were compared with those of a normal group. The difference between the two (control and patient group) was statistically significant (P<0.01). Furthermore, the effect of 1-hydroxyvitamin D₃ treatment on renal osteodystrophy was evaluated by this method. The results indicated that this method provides a useful method for assessing the response of renal osteodystrophy to treatment. Two representative cases of renal osteodystrophy are presented to illustrate the usefulness of this approach to semiquantitative whole body bone scanning.