Hypoxia induces the resistance of tumor cells[4];and the heterogeny of solid tumors result in the appearance of subpopulations of differentproliferative potency in the same tumor tissue, so that the target cells sensitive to cell cyclespecific drug are reduced.

目前有研究認(rèn)為：實(shí)體瘤部分細(xì)胞缺氧和腫瘤組織的異質(zhì)性可能是導(dǎo)致腫瘤對放療和化療產(chǎn)生耐受的主要原因之一，缺氧可以誘導(dǎo)腫瘤細(xì)胞對放療和化療的耐受性[4]一区二区欧美性爱，實(shí)體腫瘤的異質(zhì)性可使同一瘤組織內(nèi)具有不同增殖潛能的癌細(xì)胞亞群存在国产亚洲欧美日韩精品A片，導(dǎo)致細(xì)胞周期特異性化療藥物作用的靶細(xì)胞減少。

The present studies suggest that the main cause werehypoxia of the part cells of solid tumor and heterogeny of tumor tissues for the resistance oftumor cells to radiotherapy and chemotherapy.

化學(xué)治療方法作為惡性腫瘤的主要治療手段之一美女叉开腿让男生桶爽视频，但是在臨床治療的實(shí)際過程中療效往往不盡人意大逼视频，認(rèn)為其可能與：①腫瘤細(xì)胞獲得多藥耐藥性（multidrug resistance，MDR）国产精品无码一区二区应用；②化療的毒副作用手机日韩精品一区二区亚洲AV；③腫瘤的異質(zhì)性等因素有關(guān)[13]。

Based on an analysis of thecommunication subject,teaching activity,teaching form and teachingeffect, one can see that in an effective classroom communication,it is of mutual subject,interaction,heterogeny and globality.

有效課堂教學(xué)交往的特征主要體現(xiàn)在教學(xué)交往主體具有互主體性日韩成人男女福利电影在线观看视频，教學(xué)交往活動(dòng)具有互動(dòng)性亚洲熟妇天堂久久，教學(xué)交往組織具有異質(zhì)性，教學(xué)效果具有整體性人人操、人人干。