染色体畸变分析作为辐射生物剂量计的最新进展

介绍了用染色体畸变分析作为辐射生物剂量计的简史和在急性事故性照射以及早先受照中的应用。重点介绍了新近发展起来的荧光原位杂交方法对原爆幸存者，早先事故受照者和慢性职业受照者听相互易位等快速检测以及累积剂量的估算。     

电离辐射生物剂量研究现状

生物剂量计有物理剂量计不可替代的优势，其重要性和科学意义已为世界各国放射生物学家所重视。合理正确使用生物剂量计应建立在对其特性充分了解的基础上。本文简述近年来生物剂量计研究和应用的现状。     

电离辐射生物剂量研究现状

生物剂量计有物理剂量计不可替代的优势,其重要性和科学意义已为世界各国放射生物学家所重视。合理正确使用生物剂量计应建立在对其特性充分了解的基础上。本文简述近年来生物剂量计研究和应用的现状。     

GPA基因突变分析技术及其应用

较系统地介绍了GPA基因突变分析技术的原理、革新、应用及特点。研究表明,GPA可作为一种终生生物剂量计,通过检测个体GPA基因突变频率,估算其长期甚至终生接触有害环境理化因素的水平。通过比较分析个体GPA基因突变及癌症发生情况,简要讨论了该项技术在评估个体受到电离辐射或接触有害理化因素后罹患肿瘤风险方面的应用前景。     

分子辐射生物剂量计发展潜势

生物剂量估算无论在辐射事故或职业流行病学调查等方面都是不可缺少的重要手段。以细胞遗传学方法为代表的生物剂量计经过半个多世纪的发展已经非常成熟,并被广泛应用。为了更好地应对辐射突发事件,寻找具有快速、简便、适合大范围人群应用的新型分子水平生物剂量计成为目前研究的热点。为此,着重介绍近年来研究期望价值比较高的分子水平生物指示剂。     

染色体畸变分析作为辐射生物剂量计的最新进展

介绍了用染色体畸变分折作为辐射生物剂量计的简史和在急性事故性照射以及早先受照中的应用。重点介绍了新近发展起来的荧光原位杂交方法对原爆幸存者、早先事故受照者和慢性职业受照者中的相互易位等快速检测以及累积剂量的估算。     

辐射生物剂量计

介绍近几年发展起来的各种辐射生物剂量计的原理、优缺点、适用于估算剂量的类型及应用范围。     

GPA基因突变分析技术及其应用

较系统地介绍了ＧＰＡ基因突变分析技术的原理、革新、应用及特点。研究表明，ＧＰＡ可作为一种终生生物剂量计，通过检测个体ＧＰＡ基因突变频率，估算其长期甚至终生接触有豁环境理化因素的水平。通过比较分析个体ＧＰＡ基因突变及癌症发生情况，简要读讨论了该项技术在评估个体受到电离辐射或接触有豁理化因素后罹患肿瘤风险方面的应用前景。     

胞浆分裂阻滞微核法用作辐射生物剂量计的研究进展

胞浆分裂阻滞技术的建立，使人淋巴细胞微核分析成为估价染色体损伤的一个可靠和经济的方法。目前，不少研究已证实该法是除经典染色体畸变分析之外又一个可靠的生物剂量计。该法的简便快速加之其在自动化方面的新进展，将成功地应用于监测受照人群，尤其是在大量受照人员的辐射事故中将发挥其快速为临床提供生物剂量的优势。然而，由于该法建立时间尚短，还存在一些有待探讨和解决的问题，本文针对该法在用于辐射生物剂量计中的有关     

TCR基因突变分析技术及其在辐射生物学中的应用

综述了TCR体细胞基因突变检测技术的原理、特点及其在生物剂量学中的应用。研究表明,对于急性受照,TCR基因突变频率与受照剂量有明显的剂量效应关系;但TCR却不适于作为一终生生物剂量计以估算早先受照个体的受照剂量,对于长期慢性小剂量的受照情况,目前尚无明确的结论。     

放疗前后鼻咽癌患者淋巴细胞损伤的研究

目的研究放射治疗对鼻咽癌患者外周血淋巴细胞的损伤效应，探讨染色体畸变率和HPRT基因位点突变成为辐射生物剂量计的可行性。方法对鼻咽癌患者放疗前后外周血淋巴细胞染色体畸变率、HPRT基因位点突变频率分别进行检测分析。结果鼻咽癌患者放疗前外周血淋巴细胞染色体畸变率、HPRT基因位点突变频率与对照组及放疗后相比差异均有显著统计学意义。结论外周血淋巴细胞染色体畸变率、HPRT基因突变频率联合进行检测可望成为评价放疗致机体遗传学损伤的辐射生物剂量计。     

Polymer gels for in-phantom dose imaging in radiotherapy

Normoxic polymer gel dosimeters are studied, with the aim of achieving a valid and advantageous method for in-phantom 3D dose determinations. Developments were carried out in the application of such dosimetric material to the method based on dosimeter gel layers that has shown good reliability for absorbed dose imaging in radiotherapy. The technique has been improved, in particular taking care of minimizing the oxygen infiltration into the gel matrix in order to suitably avoid its effect of inhibiting the polymerization process after exposure. A suitable choice of the material of dosimeter walls has brought to achieve good steadiness in time of dosimeter sensitivity and satisfactory results in dose imaging and depth-dose profiling.     

GADD45基因--一种可能的新的生物剂量计

本文介绍了GADD45基因的辐射敏感性特征及其在细胞周期阻滞方面所起的重要作用，并对国外近期研究做了简要介绍和分析，指出该基因有可能成为一种新的生物剂量计。     

Modern dosimetric tools for 60Co irradiation at high containment laboratories

Abstract

Purpose: To evaluate an innovative photo-fluorescent film as a routine dosimetric tool during ⁶⁰Co irradiations at a high containment biological research laboratory, and to investigate whether manufacturer-provided chamber exposure rates can be used to accurately administer a prescribed dose to biological specimens.

Materials and methods: Photo-fluorescent, lithium fluoride film dosimeters and National Institutes of Standards and Technology (NIST) transfer dosimeters were co-located in a self-shielded ⁶⁰Co irradiator and exposed to γ-radiation with doses ranging from 5–85 kGy. Film dose-response relationships were developed for varying temperatures simulating conditions present when irradiating infectious biological specimens. Dose measurement results from NIST transfer dosimeters were compared to doses predicted using manufacturer-provided irradiator chamber exposure rates.

Results: The film dosimeter exhibited a photo-fluorescent response signal that was consistent and nearly linear in relationship to γ-radiation exposure over a wide dose range. The dosimeter response also showed negligible effects from dose fractionization and humidity. Significant disparities existed between manufacturer-provided chamber exposure rates and actual doses administered.

Conclusion: This study demonstrates the merit of utilizing dosimetric tools to validate the process of exposing dangerous and exotic biological agents to γ-radiation at high containment laboratories. The film dosimeter used in this study can be utilized to eliminate potential for improperly administering γ-radiation doses.     

Micronuclei in cytokinesis-blocked lymphocytes of cancer patients following fractionated partial-body radiotherapy

We applied the cytokinesis-block micronucleus assay to measure chromosome damage in lymphocytes of 11 cancer patients undergoing fractionated partial-body irradiation. Measurements performed before, during and after cessation of radiotherapy showed a dose-related increase in micronucleus frequency in each of the patients studied. When the results for micronucleus frequency (Y) were plotted against the estimated equivalent whole-body dose (X) the dose-response relationship obtained was Y = 75.8X + 49.5 (r = 0.783, P less than 0.0001). A general decline in MN frequency was observed during the post-treatment period down to 57 per cent (+/- 10) after 12 months but there was considerable variation between individuals. The advantages and disadvantages of the application of the cytokinesis-block micronucleus assay as a biological dosimeter for lymphocytes irradiated in vivo are discussed.     

电离辐射剂量监测用热释光剂量计

介绍了个人剂理监测的量，以及热释光个人剂理计的稳定性、探测阈、残余、光照影响、能量响应和无向性等性能、参数要求；提出了热释光个人剂量计的设计原则，其中包括无鉴别躯干剂量计、有鉴别躯干剂量计等；以及对热释光探测器的选择、外壳的确定、热释光个人剂理计的编码、分类和使用方法。     

A personal thermoluminescence dosimeter using LiF:Mg,Cu,Na,Si detectors for photon fields.

A new personal thermoluminescence (TL) dosimeter for photon fields using LiF:Mg,Cu,Na,Si TL detector was developed by taking advantage of its dosimetric properties including energy dependencies. Solid pellet type LiF:Mg,Cu,Na,Si detector was developed and fabricated at Korea Atomic Energy Research Institute (KAERI) and has been studied on its dosimetric properties such as TL grow curve, dose response, energy response and reusability. Its dosimetric properties show the feasibility of application of LiF:Mg,Cu,Na,Si TL detector to personal dosimetry fields. A new dosimeter using LiF:Mg,Cu,Na,Si TL detector was designed and tested through irradiation experiments. This multi-element TL dosimeter allows the measurement of a personal dose equivalent Hp(d) in photon fields. Based on the experimental results of the proposed dosimeter, it was demonstrated that a personal TL dosimeter using sintered LiF:Mg,Cu,Na,Si TL detector is appropriate to estimate personal dose equivalent for wide range energy of photon fields.     

高迁移率族蛋白B1作为电离辐射生物剂量计的初探

目的 初步研究高迁移率族蛋白B1 (high mobility group box-1,HMGB1)作为电离辐射生物剂量计的可能性。 方法 体外培养的正常人成纤维母细胞系GM接受不同剂量⁶⁰Co γ线照射后,于照后24 h收集培养液上清,经ELISA法检测其中HMGB1蛋白含量的变化,并建立剂量-效应曲线。同时采用4 Gy γ线照射后于24、48和72 h检测培养液中HMGB1的含量变化。结果 细胞培养液上清中HMGB1蛋白的含量随辐射剂量的增加而增加,照后24 h的剂量-效应曲线符合线性模式y= 0.5655 +0.0358x(r=0.9339)。且培养液上清中HMGB1蛋白含量随照后培养时间的延长而增加。结论 HMGB1是电离辐射反应性蛋白,对其进行深入研究将有助于HMGB1作为辐射生物剂量计早日应用于辐射损伤的防护与救治。     

Energy dependence measurement of small-type optically stimulated luminescence (OSL) dosimeter by means of characteristic X-rays induced with general diagnostic X-ray equipment

For X-ray inspections by way of general X-ray equipment, it is important to measure an entrance-skin dose. Recently, a small optically stimulated luminescence (OSL) dosimeter was made commercially available by Landauer, Inc. The dosimeter does not interfere with the medical images; therefore, it is expected to be a convenient detector for measuring personal exposure doses. In an actual clinical situation, it is assumed that X-rays of different energies will be detected by a dosimeter. For evaluation of the exposure dose measured by a dosimeter, it is necessary to know the energy dependence of the dosimeter. Our aim in this study was to measure the energy dependence of the OSL dosimeter experimentally in the diagnostic X-ray region. Metal samples weighing several grams were irradiated and, in this way, characteristic X-rays having energies ranging from 8 to 85 keV were generated. Using these mono-energetic X-rays, the dosimeter was irradiated. Simultaneously, the fluence of the X-rays was determined with a CdTe detector. The energy-dependent efficiency of the dosimeter was derived from the measured value of the dosimeter and the fluence. Moreover, the energy-dependent efficiency was calculated by Monte-Carlo simulation. The efficiency obtained in the experiment was in good agreement with that of the simulation. In conclusion, our proposed method, in which characteristic X-rays are used, is valuable for measurement of the energy dependence of a small OSL dosimeter in the diagnostic X-ray region.     

离体人血受照后染色体培养中若干问题的探讨

探讨了人离体血经X线照射后，染色体培养过程中松胞素B（Cyt-B)及培养时间对分裂指数（MI）的影响。结果表明：（1）0-15Gy照射，培养体系中加入Gyt-B，MI均有所增加；10Gy以上影响较在，25Gy不再有影响。（2）6-25Gy，延长培养时间MI明显增加，在6-10G 间仅靠延长时间即可获足够分析用的分裂像。（3）加Cyt-B的同时延长培养时间，其MI高于单纯加Gyt-B或延长时间者，特别是15Gy，昭后只有加Gyt-B同时延长培养时间才能使MI增多至可供分析，以上结果提示：（1）辐射事故中当以染色体畸变估算大于6Gy受昭者的剂量时，必须延长培养时间，有条件者加Cyt-B方可增加培养成功的机会，提供足够的分裂像。（2）改变培养条件，加Cyt-B并延长培养时间有可能制定出剂量上限高于5Gy的剂量效应刻度曲线，从而进一步提高其作为生物剂量计的临床应用价值。