放射损伤及放烧复合伤对小肠上皮损害的量效研究

用２８７只小鼠分别以变动照射剂量（８￣２６Ｇｙ，８个剂量）和固定烧伤深度（１５％Ⅲ°），变动烧伤面积（５％、１０％、２５％Ⅲ°）和固定照射剂量（１２Ｇｙ）致放烧复合伤（放烧），与同剂量单纯放射损伤（单放）相对比，以小肠隐窝计数和氚－胸腺嘧啶脱氧核甙（＾３Ｈ－ＴｄＲ）参入量为基本指标，结果说明放烧和单放时肠上皮效应与致伤因素间存在肯定而显著的量效关系，提出了系列数据和公式。照射剂量是决定效应的主要因

Studies of dosage-dependent effect of radiation and combined radiationburn injuries on intestinal epithelium in mice

Two hundred and eighty-seven were randomized into different groups and inflicted with whole body irradiation in 8 dosages from 8 to 26 Gy or a combined injury of radiation in 8 dosages same as those mentioned above and full thickness burns from 5% to 25% TBSA respectively to observe the dosage-depenent effects of the injuries on the intestinal epithelium.It was found that radiation, no matter when it was administered singly or combinedly with burns, played the main role to determine the injury severity of the intestinal epithelium and there was a singificant correlation of the severity of epithelial damages with the dosages of radiation, which implies that a definite dosage-effect relationship existed when the radiation injury on the intestinal epithelium was studied. The repair of the intestinal epithelium was significantly faster in the mice injured with the combination of radiation in 12 Gy, 15 Gy and 16Gy and 5%,10%,15%and 25%TBSA full thickness burns than in those mice injured with the same dosages of radiation alone(P<0. 05),which indicates that burn injury is able to promote the repair of intestinal epithelium,The dose modifying factor was 1. 20. When radiation from 18 to 26 Gy was given, the stem cells of the intestinal epithelium were almost entirely destroyed. Thus the promoting effect of combined burn injury could not be observed.