“大组讨论、小组实验”化工专业实验的新思路——以甲醇制汽油实验为例

甲醇制汽油工艺参数比较多、实验时固定床反应器中催化剂的装载和反应后的冷却过程时间比较长,在化工综合实验有限的学时内,一组学生不可能将所有的实验参数摸索清楚。针对这种情况,设计了学生“大组集体讨论+小组实验+结果汇总”的实验模式。在保证学生掌握实验基本操作的基础上,得到整个工艺的完整数据,通过对数据的处理和分析,得到一个综合性较强的实验报告。通过实践,该实验模式激发了学生的实验兴趣,提升了实验效率,取得了良好的教学效果。

No Association between p53 Immunohistochemical Staining and RASSF1 or DAPK1 Hypermethylation in Non-Small Cell Lung Cancer

p53 mutations have been linked with shortened survival rates in non-small cell lung cancer (NSCLC). Hypermethylation of RASSF1 and DAPK1 genes, which are downstream targets of p53, has also been linked to a poor prognosis in lung cancer patients. We investigated whether p53 mutations, assessed as p53 stabilization by immunohistochemistry (IHC), were independent of DAPK1 and RASSF1 promoter hypermethylation. We examined 103 resected NSCLC tumors for which we had p53 IHC and RASSF1 and DAPK1 methylation data. p53 protein expression was determined by IHC and graded using a semi-quantitative scoring method. DAPK1 and RASSF1 methylations were determined on tumor blocks by MethyLight real-time PCR assays represented as the percent of methylated reference DNA (PMR). Our primary results found no evidence for an association between the p53 IHC score and RASSF1 and DAPK1 PMR values, P = 0.46 and P = 0.68, respectively.