牙周病局部促进因素不包括() ["牙石","牙面着色","食物嵌塞","牙位异常","乳光牙本质"]
便血的原因可能有()。 ["内痔","直肠息肉","直肠癌","外痔","肠套叠"]
尿液呈棕红色或葡萄酒色,镜检无红细胞见于() ["血红蛋白尿","肾结核","卟啉尿","钩端螺旋体病","急性前列腺炎"]
肺源性心脏病的主要死亡原因是()。 ["心力衰竭","肝衰竭","肝肾综合征","心律失常","呼吸衰竭"]
关于少尿和无尿的原因,不正确的是() ["有效血容量减少","休克","高血压危象","原发性醛固酮增多征","大剂量使用氨基糖苷类抗生素"]
简述亚急性联合变性的临床表现。