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1引言胰腺癌是消化系统常见的恶性肿瘤之一,其发病率逐年上升,位居恶性肿瘤第十位,死亡率为第四位,五年生存率仅为5%,预后差。其早期诊断困难,一经发现大多属中晚期,失去了手术治疗的机会。胰腺癌对放化疗不敏感,治疗后容易复发,术后复发和转移的机制仍很不清楚,成为其治疗失败的主要原因。干细胞学说认为:干细胞是一类具有自我更新与增殖分化能力的细胞,在特定的条件下,它可以分化成不同的功能细胞,形成多种组织和器官。按分化阶段不同,分为
1 Introduction Pancreatic cancer is one of the common malignant tumors in digestive system. The incidence of pancreatic cancer is increasing year by year. It ranks 10th in malignant tumors with the fourth highest death rate. The five-year survival rate is only 5% and the prognosis is poor. Its early diagnosis is difficult, once found mostly in the advanced stage, lost the chance of surgical treatment. Pancreatic cancer is not sensitive to radiotherapy and chemotherapy, relapse after treatment, the mechanism of postoperative recurrence and metastasis remains unclear, becoming the main reason for the failure of treatment. Stem cell theory that: stem cells are a class of self-renewal and proliferation and differentiation of cells, under certain conditions, it can differentiate into different functional cells, the formation of a variety of tissues and organs. Differentiation stage by different, divided into