細胞週期指能持續分裂的真核細胞從一次有絲分裂結束後生長，再到下一次分裂結束的循環過程。細胞週期一般可分為四個階段：G1(DNA合成前期)、S(DNA合成期)、G2 (DNA合成後期)、M(分裂期)，不同種的細胞其週期的長短各不相同。本研究中，我們透過螢光泛素細胞週期標誌物(Fucci)技術標記在G1期及S/G2/M期的細胞，利用蛋白質震盪現象，使細胞處於G1期會發出紅色螢光，而處於G2/S/M期時則會發出綠色螢光。在每個觀測時間紀錄紅色螢光及綠色螢光影像，並透過影像處理計算實驗影像中G1期及S/G2/M期細胞數。用數值模擬分析細胞分裂模型，其中關鍵的想法是利用細胞在G1期比例隨時間的變化來估計細胞週期與G1期長度，並以蒙地卡羅法與最小平方法校正估計值，求出估計週期與實際週期之間的校正函數，最後用兩種不同細胞SH-SY5Y、HEK293驗證此數學模型。細胞週期的研究與癌症研究密切相關，若此模型估計具有高準確度，未來可以應用在癌症相關研究及生物醫學藥物研究。

The cell cycle is defined as the period between successive divisions of a cell. During this period, the genetic material will be completely duplicated, and the duplicates must be distributed equally and exactly to two daughter cells. The cell cycle consists of four distinct phases: G1 phase, S phase (synthesis), G2 phase (collectively known as interphase) and M phase (mitosis). In this study, we use Fucci technology to mark cells and distinguish the cells in G1 phase from other phases. Our goal is to estimate the cell cycle time by the frequency of the ratio of cells in G1 phase, which is calculated by image processing. We present a model of cell progression and find the formula between the estimated cycle time and actual cell cycle time by numerical simulation and regression analysis.

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