患者发病急骤,痢下鲜紫脓血,腹痛剧烈,里急后重较甚,壮热口渴,舌红绛苔黄燥,脉滑数。其诊断是
A.湿热痢B.疫毒痢C.休息痢D.寒湿痢E.以上均非
参考答案:B
下列情况引起的变异属于基因重组的是[ ]
A.DNA分子中发生碱基对的增添、缺失或改变
B.染色体的某一片段移接到另一条非同源染色体上
C.同源染色体的非姐妹染色单体之间发生局部交换
D.非等位基因的自由组合
—What a pity! We've lost the baseball game.
—It is not _______ whether you fail or succeed. The point is that you take part in it and enjoy it. [ ]
A. important
B. possible
C. natural