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Measurement of ionization distributions at nanometre level in tissue-equivalent gas

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Nuclear Science and Techniques 1998年第2期9卷 92-94页

作者： dang bing-rong Wei Zeng-Quan Li Wen-Jian Li Qiang and Zhang Shu-Min (Institute of Modern Phusics, the Chinese Academy of Sciences, Lanzhou 730000 ) Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

The developed track detector consists of two parts: a small drift region to obtain a good tracking and a relatively large multiplication region for getting an enough high gain at low pressure. All the track detector can be moved in the direction perpendicular to the beam by means of a micrometric screw. An automatic system allows the counting gas to flow continuously at constant pressure through the detector during the measurements. The system can measure ionization distributions at a few nanometer range.

关键词：放射生物学离子化粒子分布纳米级

Low dose effects on cultured mammalian cells...

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Nuclear Science and Techniques 2000年第4期11卷 276-279页

作者： WANG Ju-Fang, LI Wen-Jian, ZHOU Guang-Ming, HE Jing, LI Qiang, dang bing-rong, LI Xing-Lin, XIE Hong-Mei, WEI Zeng-Quan (Institute of Modern Physics, the Chinese Academy of Sciences, Lanzhou 730000) 中科院近代物理所甘肃兰州 730000

The low dose effects induced by carbon ions on Chinese hamster V79 cells and murine melanoma B16 cells were investigated in this paper. Both cell lines were divided into four groups for irradiation: (1) control, (2) 0.02 Gy or 0.05 Gy(D1), (3) 1 Gy(D2), (4) D1+D2. The survivors and micronuclei were studied as biological endpoints. The results of group (1) and group (2) showed that there were no obvious differences on micronucleus frequency but there were significant increases when irradiation dose was 0.02Gy on colony formation efficiency. Although low dose ion irradiation could not contribute to DNA damages, it could enhance the colony formation efficiency. In the study of group (3) and (4), when the ion dose was 0.02 Gy, there were evident increases on surviving fraction and decreases on micronucleus frequency, but there were no statistical changes on these endpoints when the ion dose was 0.05Gy. This meant that high LET radiation could induce the adaptive response of cultured cells, furthermore, in the range of inducing ion dose , low dose irradiation was more profitable than high dose one.

关键词：哺乳动物细胞 DNA 离子辐射低剂量效应辐射效应碳离子

Statistical Research on Megahertz-peaked Spectra Pulsars

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Research in Astronomy and Astrophysics 2025年第1期25卷 116-134页

作者： Hong-bing Cai Li Chen Shi-dang Li Kai Wang Hang Liu JSNU SPBPU Institute of Engineering & SINO RUSSIAN Institute Jiangsu Normal University School of Physics and Electronic Engineering Jiangsu Normal University

Megahertz-peaked spectra(MPS) pulsars are referred as cases whose radio spectra turn over around 100 MHz. We identified 53 MPS pulsars based on the spectral data from the literature, and statistically analyzed the spatial location distribution, the magnetic field-period distribution, peak frequencies, spectral indices, and dispersion measures of these MPS pulsars. We found that there is a strong positive correlation between the dispersion measures and the peak frequencies of MPS pulsars, and negative correlations of the dispersion measures with spectral indices and the ages are also found. Such correlations suggest that the interstellar medium is an important factor that affects observational properties of MPS pulsars.

关键词： (stars:) pulsars: general ISM: general radio continuum: general

Inhibition of mouse tumors by heavy ion irradiation

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Nuclear Science and Techniques 2000年第1期11卷 22-26页

作者： LI Wen-Jian WEI Zeng-Quan LI Qiang ZHOU Guang-Ming dang bing-rong XIE Hong-Mei WANG Ju-Fang (Institute of Modern Physics, the Chinese Academy of Sciences, Lanzhou 730000) ZHANG Xiao-Wen GUO Hong-Yun (Gansu Academy of Medical Sciences, Lanzhou 730050) 中科院近代物理所甘肃兰州 730000 甘肃省医学科学院甘肃兰州 730050

Inhibition effects, control probabilities and pathology tissue changes of mouse transplanted tumors S180 after irradiation with 50 MeVu 12C6+ ions are reported. Doses of single irradiation were 0.5, 1, 2, 5, 10, 20, 40 Gy, respectivelyl at a dose rate of 3 Gy/min. Observing time was 24 days. The results show that each group had significant inhibition action on S180 tumors and all inhibitory probabilities were more than 90%; the initial time of inducing tumor inhibition effects were within one week in high dose groups （20, 40 Gy）, and after two weeks in medium dose groups （5, 10 Gy） and low dose groups （0.5, 1, 2 Gy）; also, inhibitory effects in high dose groups were obviously greater than other groups （p <0.05）; tumor control probabilities were different in each group) those in high dose groups （20, 40 Gy） were higher and TCD50 （50% tumor control dose） was 20Gy; the results for curing tumors are different in different doses; pathology inspection presented here were tumor tissue necrosis and degeneration in each dose group and they depended on doses.

关键词：重离子照射鼠动物实验病理学说肿瘤辐射疗法抑制作用

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蛋白质组学及其在重离子治癌应用中的探讨

原子核物理评论 2005年第3期22卷 292-295页

作者：邴涛谢漪党秉荣杨媛李文建张红中国科学院研究生院中国科学院近代物理研究所甘肃兰州730000 中国科学院近代物理研究所兰州大学生命科学院

综述了蛋白质组学的主要方法和技术———双向凝胶电泳、生物质谱技术、蛋白质芯片技术,及其在肿瘤标志物的筛选和鉴定、肿瘤治疗效果的评价及肿瘤发生机制研究等方面的应用状况,并对蛋白质组学在重离子治疗中的应用进行了展望。

关键词：蛋白质组学重离子治疗癌症

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基因芯片技术及其在放射治疗中的应用

原子核物理评论 2008年第1期25卷 77-81页

作者：胡凯骞党秉荣邴涛李文建王菊芳中国科学院近代物理研究所

基因芯片技术是建立在杂交序列基本理论上的分子生物学技术,它以一种全面、综合和系统的思维方式研究生命现象。基因芯片技术可以完整地研究整个细胞或器官全部基因变化,可以通过基因分析发现对电离辐射的基因反应差异,从而建立一种新... 详细信息

基因芯片技术是建立在杂交序列基本理论上的分子生物学技术,它以一种全面、综合和系统的思维方式研究生命现象。基因芯片技术可以完整地研究整个细胞或器官全部基因变化,可以通过基因分析发现对电离辐射的基因反应差异,从而建立一种新的分子放射生物学方法。综述了基因芯片技术及应用领域,重点介绍了基因芯片技术在辐射治疗癌症中的应用。概述了重离子治疗肿瘤优于其它射线的原因。展望了利用基因芯片技术的优势探索肿瘤经重离子辐照前、中、后期的生物学效应。

关键词：基因芯片放射治疗重离子

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重离子束适形放射治疗技术

原子核物理评论 2001年第2期18卷 109-115页

作者：李强卫增泉李文建温小琼党秉荣中国科学院近代物理研究所甘肃兰州730000

重离子束适形放射治疗技术主要包括束流配送系统和治疗计划系统等 .前者是实现重离子束适形放射治疗的硬件设施 ,后者为适形治疗的软件支撑系统 ,两者缺一不可 .鉴于重离子束与物质相互作用在物理学及生物学效应上表现出的特殊性 ,重离... 详细信息

重离子束适形放射治疗技术主要包括束流配送系统和治疗计划系统等 .前者是实现重离子束适形放射治疗的硬件设施 ,后者为适形治疗的软件支撑系统 ,两者缺一不可 .鉴于重离子束与物质相互作用在物理学及生物学效应上表现出的特殊性 ,重离子束治癌中特别引入了面向生物学效应的适形治疗和束流的正电子断层在线监控技术 .

关键词：重离子束适形放射治疗束流配送治疗计划生物效应

Metagenomic perspectives on antibiotic resistance genes in tap water:The environmental characteristic,potential mobility and health threat

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Journal of Environmental Sciences 2025年第1期147卷 582-596页

作者： Qiyue Meng Yibo Zhang Da He Yu Xia Jie Fu Chenyuan dang School of Environmental Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory of Ecological Impacts of Hydraulic Projects and Restoration of Aquatic Ecosystem of Ministry of Water Resources Institute of HydroecologyMinistry of Water Resources&Chinese Academy of SciencesWuhan 430074China School of Environmental Science and Engineering College of EngineeringSouthern University of Science and TechnologyShenzhen 518055China

As an emerging environmental contaminant,antibiotic resistance genes(ARGs)in tap water have attracted great *** studies have provided ARG profiles in tap water,research on their abundance levels,composition characteristics,and potential threat is still ***,9 household tap water samples were collected from the Guangdong-Hong Kong-Macao Greater Bay Area(GBA)in ***,75 sets of environmental sample data(9 types)were downloaded from the public *** was then performed to explore the differences in the abundance and composition of ARGs.221 ARG subtypes consisting of 17 types were detected in tap *** the ARG abundance in tap water was not significantly different from that found in drinking water plants and reservoirs,their composition *** tap water samples,the three most abundant classes of resistance genes were multidrug,fosfomycin and MLS(macrolide-lincosamidestreptogramin)ARGs,and their corresponding subtypes ompR,fosX and macB were also the most abundant ARG *** the potential mobility,vanS had the highest abundance on plasmids and viruses,but the absence of key genes rendered resistance to vancomycin ***,the majority of ARGs present in tap water were those that have not been assessed and are currently not listed as high-threat level ARG families based on the World Health Organization *** the current potential threat to human health posed by ARGs in tap water is limited,with persistent transfer and accumulation,especially in pathogens,the potential danger to human health posed by ARGs should not be ignored.

关键词： Antibiotic resistance genes Tap water Plasmids Viruses Health threat

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低剂量连续辐射引起的小鼠免疫系统的变化

原子核物理评论 2009年第4期26卷 348-351页

作者：谢漪张红党秉荣郝冀芳王小虎中国科学院近代物理研究所甘肃兰州730000 甘肃省医学科学研究院甘肃兰州730050

为了评估低剂量X射线连续辐射对BALB/c小鼠健康机体免疫系统的影响,实验采用X射线全身连续照射BALB/c小鼠,照射第一天剂量为0.07Gy,剂量率0.2Gy/min,之后每天照射0.08Gy,共照射12d,累积剂量1.03Gy,照射后24和48h取血、胸腺和脾脏。流式... 详细信息

为了评估低剂量X射线连续辐射对BALB/c小鼠健康机体免疫系统的影响,实验采用X射线全身连续照射BALB/c小鼠,照射第一天剂量为0.07Gy,剂量率0.2Gy/min,之后每天照射0.08Gy,共照射12d,累积剂量1.03Gy,照射后24和48h取血、胸腺和脾脏。流式细胞仪检测免疫细胞周期和凋亡的变化,胸腺和脾脏指数用重量法获取。实验结果表明,小鼠胸腺细胞的周期在照射后24h被阻滞在G2/M期;外周血淋巴和胸腺细胞周期48h被阻滞在G0/G1期,细胞凋亡比例在照射后两个时间点都显著增加;脾脏淋巴细胞周期24h被阻滞在G0/G1期,48h被阻滞在S期,细胞凋亡比例在24和48h显著减少;脾脏指数在照射后48h显著减少。故低剂量X射线连续全身照射BALB/c小鼠可激活免疫细胞不同的周期监测点,引起免疫细胞凋亡比例发生变化,造成一定的辐射损伤,且这种影响随着免疫器官的不同而不同。

关键词： X射线连续辐射免疫细胞细胞周期和凋亡脾脏和胸腺指数小鼠