随机区组方差分析中,总例数为N,处理组数为k,配伍组数b,则处理组组间变异的自由度为() ["(b-1)(k-1)","b-1","N-k","k-1","N-1"]
肾盂造影发现原来的结石下降至输尿管上段。典型的症状为()膀胱结石典型的症状是() ["尿潴留","尿急、尿频","排尿困难","排尿中断","肾绞痛和镜下血尿"]
动静脉畸形最常见的症状是() ["癫痫","出血","偏瘫","失语","精神障碍"]
某药物研究中心为研究减肥药的效果,将40只体重接近的雄性大白鼠随机分为4组,分别给予高剂量、中剂量、低剂量减肥药和空白对照4种处理方法,上述资料所用的设计方法为() ["析因设计","随机区组设计","交叉设计","完全随机设计","序贯试验"]
典型动静脉畸形由() ["动脉和静脉组成","供血动脉、畸形血管团和引流静脉组成","供血动脉、毛细血管和引流静脉组成","畸形血管团组成","静脉动脉化形成"]
多尿是指每昼夜尿量长期保持在()少尿是指每昼夜排出尿量为()无尿是指每昼夜排出尿量为()正常成人每昼夜排出尿量约为()