摘要
生物體中幾乎所有生理表現均由微小的電磁訊號傳遞來完成，而生物體中分子的鍵結其能量均遠大於微波及極低頻電磁場的能量。該電磁場之能量雖不足以打斷其鍵結，但對這些具有電子的分子會有極化、飄移等作用，因此可能對細胞造成影響。

今我們先以鈷60或過氧化氫在溶液中所產生的自由基來攻擊V79-4細胞的DNA，使細胞關於修復DNA的基因能夠表現而進行修復DNA的工作。在修復的同時，我們給予不同的電磁波照射；之後利用MTT比色分析法來觀察細胞的存活率。MTT比色分析法的原理是利用MTT藥劑會與粒線體上電子傳遞鏈中的電子產生作用，使其顏色由黃轉紫，測其OD值以換算成細胞存活率。實驗結果顯示，不論是以鈷60或是過氧化氫所傷害的細胞，在修復DNA的同時若以極低頻電磁場加以照射，並不會影響其存活率。但對DNA已受到傷害的細胞加以照射微波波段電磁波時，經過統計的檢定後發現存活率有明顯的下降趨勢。為確認細胞是在受到DNA傷害後其存活率才會受到電磁波的影響，將細胞直接以不同頻率的電磁波照射而加以觀察，並未發現其存活率有明顯變化。

另外我們也使用單細胞電泳法來觀察細胞中DNA受損的情形。因本次實驗無法觀察小劑量鈷60照射或是過氧化氫的傷害，所以將來改進之道為找到更好的實驗條件，如電泳時間、電泳液的成分等以利用電泳法觀察細胞中DNA受損情形。

Abstract
All functions in biological system are almost accomplished by transduction of electromagnetic signal; the binding energy among these biological molecules is larger than that of microwaves and extremely low frequency(ELF) electromagnetic(EM) fields. The energy of EM waves is incapable of breaking the bindings, but affect the electrons within the molecules for their polarization and drift, etc. So the cell properties may be influenced by the EM waves.

In this dissertation, we utilized the free radicals that were generated by from Co-60 or hydrogen peroxide to attack the DNA of the V79-4 cell. The DNA repair-gene was triggered to repair the free radical damaged DNA. Meanwhile, The EM waves irradiated the target cell. The 2-[4,5– Dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay presented the surviving fraction of the cell. The MTT powder changed the color from yellow to purple by an interaction between the reagent and the electrons in the electron-transport chain on the mitochondria. The optical density (OD) value retrieved from MTT assay deduced the surviving fraction of the cell. The results indicated that the ELF EM wave had no influences on the surviving fraction of the cells that were damaged by Co-60 or hydrogen peroxide. However, when the microwaves irradiated on the DNA-damaged cells, the statistical test clarified that the surviving fraction of the cell decreased significantly. In order to confirm the DNA-damaged cells were sensitive to EM waves, the microwaves and ELF EM waves were irradiating the cells that the DNA was not damaged. After obtaining the surviving fraction of the undamaged cell the experiments indicated that surviving fraction had no significant variation.

In addition, we measure the DNA damages by single cell gel electrophoresis method. Nonetheless, the slight dose irradiator of Co-60 or hydrogen peroxide performed no effect in the strategy. The experimental conditions, such as the electrophoresis time and running buffers, could be further optimized in the future research.

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