微波与γ射线对K562细胞的复合效应实验研究

发布时间：2018-08-02 21:24

【摘要】： 微波是一种频率在300MHz至300GHz之间的电磁波,微波辐射是一种非电离辐射,与生物组织的相互作用有热效应和非热效应二种不同机制。热效应和非热效应始终同时存在,只是在高强度辐射场(功率密度大于10 mW/cm2)中,主要表现为热效应。而在长时间、低功率密度辐射场下,微波的非热效应占主导地位。生物体对微波作用所产生的响应是一种非线性响应,微波的生物效应具有“窗效应”的多样性。 γ射线是一种电离辐射,电离辐射为高能辐射,可以直接作用于生物分子,也可以通过水分子的激发和电离的间接作用,引起强烈而复杂的生物学效应。被激发和电离的靶分子和水分子常常形成多种自由基。γ辐射的生物效应是建立在对分子和基团激发和电离作用,特别是通过了自由基作为中介的基础上,使最终被作用的生物分子发生结构和功能的变化。本质上都是电磁辐射的微波和电离辐射,只是能量或频率有所不同,却能在维持高度有序结构的生命系统,借助于内在的相干性和协同性,表现出生物效应的多样性。因此,对各个频段的电磁辐射的生物效应及机制的研究和应用一直受到关注。不过,至今对非电离辐射(微波辐射)复合电离辐射(γ射线)的生物效应研究报道很少。本文以白血病K562细胞株为生物模型,以细胞增殖率以及凋亡率等为测试指标,并设立人血正常淋巴细胞和红外辐射为对照,研究了频率为9.3GHz、功率密度在0.5 mW/cm2~ 15 mW/cm2范围的连续微波辐射复合稳定的γ射线辐射场(样品被照射的照射量率为5.0mC/Kg.hr)作用对细胞的效应实验规律,从中探索低功率微波场效应复合γ射线本底辐照下生物效应的实验规律与生物物理机制,特别是窗效应的具体表现,以及协同作用的类型和规律,最后提出了细胞的不同频率波段电磁波协同作用的生物物理模型。研究结果显示: 1.微波能明显的抑制K562细胞的活性与诱导细胞凋亡,且这种抑制作用和诱导凋亡的作用较微波对人淋巴细胞的作用强。微波对K562细胞的生物效应表现出非线性和明显的“窗效应”。作用“时间窗”表明在微波辐照功率密度为15 mW/cm2时,微波对K562细胞的增殖抑制作用以及诱导凋亡作用的效应最大值均发生在辐照时间
[Abstract]:Microwave is a kind of electromagnetic wave with frequency from 300MHz to 300GHz. Microwave radiation is a kind of non-ionizing radiation. The interaction between microwave and biological tissue has two different mechanisms: thermal effect and non-thermal effect. Thermal effect and non-thermal effect always exist at the same time, but in the high intensity radiation field (power density > 10 mW/cm2), the thermal effect is the main manifestation. For a long time, the non-thermal effect of microwave is dominant in low power density radiation field. The response of organism to microwave is a nonlinear response. The biological effect of microwave has the diversity of "window effect." 纬-ray is an ionizing radiation. Ionizing radiation is high energy radiation, which can act directly on biological molecules, but also cause strong and complex biological effects through the activation of water molecules and indirect effects of ionization. The biological effects of 纬 radiation are based on the excitation and ionization of molecules and groups, especially through free radicals acting as mediators. Changes in the structure and function of the biological molecules that are eventually acted upon. Microwave and ionizing radiation of electromagnetic radiation are essentially electromagnetic radiation, but the energy or frequency is different, but it can show the diversity of biological effects in the life system which maintains a highly ordered structure by virtue of the inherent coherence and synergy. Therefore, the study and application of biological effects and mechanisms of electromagnetic radiation in various frequency bands have been paid close attention to. However, there are few studies on biological effects of nonionizing radiation (microwave radiation) combined ionizing radiation (纬-ray). The K562 leukemia cell line was used as a biological model, the cell proliferation rate and apoptosis rate were used as test indexes, and human normal lymphocytes and infrared radiation were used as control. The effects of continuous microwave irradiation on cells with a frequency of 9.3 GHz and a power density of 0.5 MW / cm ~ 2 ~ 15 mW/cm2 were studied. The effects of the complex and stable 纬 -ray radiation field (the exposure rate of the sample exposed to 5.0mC/Kg.hr) on the cells were studied. The experimental law and biophysical mechanism of biological effect under low power microwave field effect combined with 纬 -ray background irradiation, especially the manifestation of window effect, as well as the types and rules of synergistic effect are explored. At last, a biophysical model of electromagnetic wave synergy in different frequency bands of cells is proposed. The results show that: 1. Microwave could obviously inhibit the activity of K562 cells and induce apoptosis, and the inhibitory and apoptotic effects of microwave were stronger than those of microwave on human lymphocytes. The biological effects of microwave on K562 cells showed nonlinear and obvious "window effect". The "time window" showed that when the power density of microwave irradiation was 15 mW/cm2, the inhibition of proliferation and the maximum effect of apoptosis induced by microwave on K562 cells occurred at the irradiation time.
【学位授予单位】：第三军医大学
【学位级别】：硕士
【学位授予年份】：2006
【分类号】：R312

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