人肝癌细胞受重离子照射后的微核及存活的动态观察

研究了２５ＭｅＶ／ｕ＾４０Ａｒ＾１４＋辐照人肝癌细胞ＳＭＭＣ－７７２１的微核及存活的动态变化，结果表明：单次照射与分次照射的微核率随时间的变化规律没有明显区别。受辐照肝癌细胞的生长明显低于对照，而且随培养时间的延长，癌细胞的存活数表现出衰减趋势，微核率与细胞存活数关系的动态变化为负相关性。０．６８、６．８和６８Ｇｙ辐照的细胞，培养２４ｈ的微核率比培养９６ｈ的微核率低，培养２４ｈ和４８ｈ的肝癌细胞的     

DL—苏氨酸辐照效应的谱学研究

用电子自旋（ＥＳＲ）波谱、固体高分辨核磁共振＾１３Ｃ ＮＭＲ谱以及Ｘ－衍射光谱，探讨了ＤＬ－苏氨酸（Ｔｈｒ）的γ辐照稳定性。Ｔｈｒ的＾１３Ｃ ＮＭＲ化学位移和Ｘ－射线衍射数据结果表明，Ｔｈｒ多晶固体在１００ｋＧｙ剂量范围内的化学结构是稳定的。ＥＳＲ谱强度和＾１３Ｃ共振谱线宽随着剂量的增加而增大，是辐照自由基浓度的变化所致。     

137Cs辐照和MAP综合处理对猪肉中沙门氏菌的影响

进行了＾１３７Ｃｓ辐照和ＭＡＰ综合处理对沙门氏菌在灭菌猪肉中致死和残存菌生长状况的研究。研究采用反应面设计，并由得到的数据推算回归方程。结果表明，沙门氏菌的致死明显受辐照剂量的影响，残存菌量的对数与辐照剂量成反比：而ＭＡＰ对辐照沙门氏菌的致死无明显影响。５种不同ＣＯ２体积分数对沙门氏菌辐照后的残存菌生长也无明显影响。辐照和ＭＡＰ综合处理并不比单纯辐照能更有效地控制沙门氏菌的致死和残存菌的生长。与空     

^90Y,^32P—GTMS介入治疗恶性肿瘤的实验研究与初步临床应用

采用介入治疗法，将＾９０Ｙ－ＧＴＭＳ和＾３２Ｐ－ＧＴＭＳ直接注入癌性肿块中，以达到杀灭癌细胞、抑制肿瘤生长、延长恶性肿瘤患者生存期的目的。在荷瘤裸鼠模型的瘤体上进行对照组、“冷”球组、不同剂量组（＾９０Ｙ－ＧＴＭＳ剂量分组为９２．５、１８５、３７０ＭＢｑ，＾３２Ｐ－ＧＴＭＳ剂量分组为３７、９２．５、１８５ＭＢｑ）的治疗，治疗后不同时间观察疗效，获得核素在单位体积中有效剂量后应用于临床。借助Ｂ超对肿     

离子辐照聚合物薄膜引起的降解和能量传输过程

用１２０ｋｅＶＮ＾＋，Ａｒ＾＋，Ｆｅ＾＋辐照聚酰亚胺薄膜，辐照剂量为５×１０＾１４－１×１０＾１７ｉｏｎｓ／ｃｍ＾２，对辐照样品做了表面电阻和光学吸收数量，结果表明：辐照后样品的表面电阻有明显变化，且随辐照剂量变化呈现阈值，在高剂理下达到饱和值。     

NMOS晶体管的退火特性研究

探讨了加固型ＣＣ４００７经＾６０Ｃｏγ射线辐照后ＮＭＯＳ晶体管的退火特性，研究了辐照敏感参数随辐照剂量、退火温度、退火时间和退火偏置的变化关系。经相同总剂量辐照的器件，高源１００℃下的退火速度远大于室温２５℃下退火速度。２５￣２５０℃下的等时退火，其退火程度接近１６８ｈ的１００℃等温退火。对不同的退火情况，退火偏置的作用是相似的，＋５Ｖ栅偏压退火速度大于０Ｖ栅偏压和浮空退火速度。对氧化物陷阱电荷的     

γ射线诱导的哺乳动物细胞基因突变

观察了电离辐射对中国仓鼠细胞ＣＨＯ－Ｋ１和人细胞ＨｅＬａ ＭＲ的非必需基因ｈｐｒｔ和必需基因Ｎａ＾＋／Ｋ＾＋ＡＴＰ酶的基因致突能力。γ射线能增加两种细胞ｈｐｒｔ基因的突变频率，照射剂量和突变频率呈正相关，在相同的照射剂量下ＣＨＯ－Ｈ１的突变频率高于ＨｅＬａ ＭＲ，提示在ｈｐｒｔ位点，鼠细胞对辐射的敏感性比人细胞高。在Ｎａ＾＋／Ｋ＾＋ＡＴＰ酶基因位点，辐射不能增加两种细胞的突变频率。ＨＰＲＴ和Ｎａ＾     

浓缩铀诱发免疫细胞凋亡的形态观察及IL—2和IL—6的 …

对浓缩铀＾２３５Ｕ内照射人淋巴细胞白血病细胞株Ｍｏｌｔ－４细胞和巨噬细胞株Ａｎａ－１细胞诱发的细胞凋亡及细胞因子的防护作用进行了研究。实验中估算了＾２３５Ｕ在不同阶段培养细胞中的辐射累积吸收剂量。通过荧光显微镜形态观察，发现免疫细胞在受＾２３５Ｕ辐照后，可诱发明显的以核断裂和核固缩为特征的细胞凋亡。     

5.0MeV和9.5MeV快中子辐照在GaAs中产生的辐射损伤的正电子湮没研究

采用正电子湮没寿命测量方法研究了５．０ＭｅＶ和９．５ＭｅＶ快中子辐照在ＧａＡｓ中产生的辐射损伤，实验结果表明１０＾１１－１０＾１２ｎ／ｃｍ＾２注量的中子辐照只产生单空位缺陷１０＾１３ｎ／ｃｍ＾３注量的中子辐照产生单空位和双空位缺陷，１０＾１２ｎ／ｃｍ＾２注量的９．５ＭｅＶ中子辐照的ＧａＡｓ经４５０－６２０℃退火产生三空位缺陷，产生的缺陷浓度随中子能量和注量的增大而增大，但缺陷产生率对中子注量更灵敏     

高能Ar离子辐照单晶Si引起的损伤研究

用１１２ＭｅＶ Ａｒ离子以５０Ｋ的低温辐照了〈１１１〉取向的单晶Ｓｉ后在室温下采用Ｘ射线光电子谱（ＸＲＳ）、电子顺磁共振（ＥＰＲ）和红外光吸收（ＩＲ）技术对样品进行了分析。ＸＰＳ分析结果表明，表面处Ｓｉ以单元素和ＳｉＯ２两种形式共存，辐照对这两种形式Ｓｉ的２ｐ轨道电子的结合能影响较小。ＥＰＲ测量结果显示，Ｓｉ中的损伤产生明显地依赖于辐照剂量，当剂量为１．０×１０＾１４－１．８×１０＾１４ｃｍ＾－２     

C谱紫外线对体外培养小鼠胚细胞的影响

本实验对紫外线致体外培养的小鼠胚细胞的效应进行了研究。胚细胞取自１１天胎龄绵小鼠前，后肢芽及中脑，并用小脑成纤维母细胞株３Ｔ３进行参照。实验结果表明，在０－３０Ｊ／ｍ＾２的紫外线照射下观察到胚细胞生长和分化抑制作用及胸腺嘧啶聚合物和光产物的形成。紫外线对胚细胞分化的抑制作用比对增殖和抑制作用强，其对ＤＮＡ的损伤作用在胚细胞与参照细胞间相似，这两类细胞对ＤＮＡ损伤的修复动力学相似。     

Potential role of DNA-dependent protein kinase in cellular resistance to ionizing radiation

In this paper, we study the ability of DNA-PK-deficient (M059J) and -proficient (M059K) cells to undergo the rate of cellular proliferation, cell cycle distribution and apoptosis after 10 Gy X-ray irradiation, and the role of DNA-PK in radiosensitivity. The results showed that M059J cells exhibited hyper-radiosensitivity compared with M059K cells. A strong G2 phase arrest was observed in M059J cells post irradiation. Significant accumulation in the G2 phase in M059J cells was accompanied by apoptosis at 12 h. Altogether, the data suggested that DNA-PK may have two roles in mammalian cells after DNA damage, a role in DNA DSB repair and a second role in DNA-damaged cells to traverse a G2 checkpoint, by which DNA-PK may affect cellular sensitivity to ionizing radiation.     

应用单细胞微凝胶电泳技术检测成纤维细胞的放射敏感性

应用单细胞微凝胶电泳（SCGE）技术以及噻唑蓝（MTT）比色法检测辐射诱发的成纤维细胞系AT5BIVA和GM637的初始DNA双链断裂数及断裂拍的修复与细胞放射敏感性之间的关系。结果表明,AT5BIVA细胞系的放射敏感性显著高于GM637。两种细胞系的初始DNA双链断裂数均随剂量的增加而增加,呈显著的剂量效应关系,在给定的剂量点,辐射诱发的AT5BIVA细胞系的初始DNA双链断裂数显著高于GM637。AT5BIVA纱对辐射诱发的DNA双链断裂的修复能力小于GM637。结果提示,辐射诱发的初始DNA双链断裂数及断裂后的修复与细胞的放射敏感性均有一定的相关性,作为细胞放射敏感性预测指标具有很大的应用潜势。     

微细胞介导染色体转移法提高AT5 BIVA细胞对电离辐射的抗性

ＡＴ５ＢＩＶＡ细胞是一株经ＳＶ４０病毒转化的ＡＴ病人皮肤成纤维细胞，对γ射线高度敏感。实验用ＦＤ３（含人第１１号染色体的人鼠杂种细胞）、ＦＤ８（不含人第１１号染色体的人鼠杂种细胞）、ＬＭ／ＴＫ鼠细胞）为洪体，通过微细胞介导染色体转移（ＭＭＣＴ）向ＨＴ５ＢＩＶＡ细胞导入人或鼠的完整染色体，经两次３Ｇｙγ射线照射筛选后，获得ＡＴ５ＢＩＶＡ与ＦＤ３微细胞融合的杂合细胞ＡＴ／ＦＤ３－１，对γ射线抗性有显著提高。而ＦＤ８或ＬＭ／ＴＫ的微细胞与ＡＴ５ＢＩＶＡ细胞的杂合细胞，对γ射线抗性未增加。枝型分析表明ＡＴ／ＦＤ３—１细胞中包含了来源于ＦＤ３细胞的人第１１，１４号染色体和数条鼠染色体。通过对照实验，排除了人１４号和鼠染色体提高ＡＴ／ＦＤ３－１细胞对γ射线抗性的可能性．确认人第１１号染色体与ＡＴ细胞对电离辐射敏感性相关，提示人第１１号染色体上可能存在决定细胞对γ射线抗性的相关基因。     

间充质干细胞(MSC)在辐射损伤救治方面的研究进展

随着核能在军事及民用领域的广泛应用,辐射损伤事件的发生机率逐渐增加。辐射会引起机体造血、免疫、胃肠道、肺、皮肤等多种组织器官受损,目前治疗策略对受大剂量照射病人疗效难以令人满意。间充质干细胞(mesenchymal stem cell,MSC)是一类低免疫原性、适合异体应用、具有多向分化潜能的干细胞。MSC具备独特免疫调节及造血支持功能,能够通过直接分化、分泌一系列细胞因子、生长因子及胞外微囊等方式促进受辐射损伤机体造血重建及受损组织修复,兼顾辐射损伤病人救治过程中造血重建、组织修复两方面的重点及难点问题。近年来MSC在辐射损伤救治方面的研究取得了一些新进展,本文着眼于此作一综述,以期为辐射损伤的救治提供一些参考。     

槲皮素对HeLa细胞辐射敏感性影响及其机理

为探讨药物槲皮素对HeLa宫颈癌细胞的辐射敏感性影响及其机理,使用不同浓度的槲皮素和不同照射剂量处理HeLa细胞,采用克隆形成法测定细胞存活率,应用流式细胞术测定细胞DNA双链断裂,以及测定槲皮素与电离辐射联合作用对HeLa细胞的周期影响.结果显示,不同槲皮素浓度处理组的HeLa细胞在不同照射剂量组间的存活率比较有统计...     

Irradiation devices and irradiation programmes at the high flux reactor (HFR) Petten for the investigation of the irradiation behaviour of stainless steels

Irradiation testing of stainless steels represents an important share in the utilization spectrum of the high flux reactor (HFR) Petten. These tests address in particular austenitic and martensitic steels for thermo-nuclear fusion reactors, austenitic steels for fast breeder reactors, and stainless steels and Cr---Ni-alloys for light water reactors.A number of well-proven irradiation devices covering an extensive range of applications and operated by a vastly experienced group are available at the HFR. In addition, at the Petten hot cells, many diversified tools exist for irradiation testing of stainless steel. The irradiation devices are tailored to provide typical, reactor specific environment conditions to the samples. Such conditions are maintained within narrow specifications. In this respect, the long lasting operational experience originating from the many materials irradiation programmes performed at the HFR, the high and consistent availability of the HFR and its reliability with regard to provision of predictable and reproducible irradiation conditions, are the keys to these many demonstrable experiments. The adjustment of typical neutron spectrum at the irradiation samples is performed through an appropriate choice of structural materials and their arrangement within the irradiation device. Many irradiation devices are reloadable, being specially suited for intermediate unloading and hot cell measurement of the irradiated samples. Other devices are equipped with integral loading and measuring systems for in-pile measurement of characteristic irradiation parameters (e.g. the creep behaviour). The neutron fluence is calculated and then measured after irradiation from neutron fluence monitor sets which are integrated into the sample carriers.The post irradiation examination and testing of the irradiated samples is performed either at the customer's hot cells or at the Petten hot cells, in particular, when intermediate measurements are required. Dedicated and specialized testing equipment for tensile, creep, Charpy, fatigue and crack propagation testing, various microscopy systems (SEM, TEM) and other test equipment (gamma-scanning, chemical analysis, image analysis, etc.) are all available at the Petten hot cells.     

STIMULATING EFFECT OF LOW DOSE ~(147)Pm ON DNA REPAIR IN SPERMIOGENIC STAGES

ＳＴＩＭＵＬＡＴＩＮＧＥＦＦＥＣＴＯＦＬＯＷＤＯＳＥ~（１４７）ＰｍＯＮＤＮＡＲＥＰＡＩＲＩＮＳＰＥＲＭＩＯＧＥＮＩＣＳＴＡＧＥＳＳＴＩＭＵＬＡＴＩＮＧＥＦＦＥＣＴＯＦＬＯＷＤＯＳＥ~（１４７）ＰｍＯＮＤＮＡＲＥＰＡＩＲＩＮＳＰＥＲＭＩＯＧＥＮＩＣＳＴ...     

电离辐射引起的DNA链断裂损伤及其修复

DNA链断裂是电离辐射的主要生物学效应之一,单链断裂由一次击中造成,所以与辐射剂量成线性关系,双链断裂可以一次击中造成,也可由两个位置相关的单链断裂迭加而成,所以与辐射剂量成线性——平方关系。已有各种理化方法能测定活细胞内的单链断裂和双链断裂数。细胞具有修复DNA链断裂的能力,但其机制远不如切除修复机制那么清楚。未修复的链断裂是致死的,被修复的单链断裂完全恢复DNA的正常结构与功能,被修复的双链断裂的生物学效应如何还不清楚。剂量率对辐射的生物学效应有重要影响。     

Bystander effects induced by medium from carbon-ion irradiated human cancer cells

The bystander effects induced by medium from human hepatoma SMMC-7721 and adenocarcinoma F56 cells irradiated with carbon ions were investigated. It was found that the survival fraction （SF） of the irradiated cells decreased exponentially along with the increased dose. SMMC-7721 cells were more radiosensitive than F56 cells. The plating efficiency （PE） of the non-irradiated cells treated with irradiated conditioned medium （ICM） was obviously lower than the PE of control cells for SMMC-7721 cells but not for F56 cells. Moreover, the reduced PE and SF by ICM treatment were more significant for IGy irradiation than for 6Gy irradiation on SMMC-7721 cells, These results suggest that the irradiated cells can secrete factor（s） into medium that is cytotoxic to bystander non-irradiated cells. The bystander effects are dependent on cell genotype presented at the time of irradiation and radiation dose, This makes impact on the precise estimation of the effects of radiation and tumor radiotherapy,