谷氨酰胺是
A. 氨的解毒产物
B. 氨的储存形式
C. 氨的转运形式
D. 必需氨基酸
从各医院收集病例组成队列进行预后研究,最有可能的偏倚是:()
A. 存活队列偏倚
B. 迁移偏倚
C. 测量偏倚
D. 霍桑效应
E. 志愿者偏倚
大样本分组资料计算生存率用:()
A. 寿命表法
B. Kaplan-Meier法
C. 时序检验
D. t检验
E. F检验
Unfortunately, we now have plenty of evide____ that many children do notdo half as well on tests as they actually could if they tried.
A. evidence
B. blocks
C. suitability
D. instruction