钠石灰的颗粒大小以筛孔表示,哪项气流阻力小、吸收二氧化碳效果最好() ["0.5~1筛孔","2~3筛孔","4~8筛孔","9~10筛孔","11~12筛孔"]
科学家将含人的α—抗胰蛋白酶基因的DNA片段,注射到羊的受精卵中,该受精卵发育的羊能分泌含α—抗胰蛋白酶的奶。这一过程没有涉及到() ["A、RNA以自身为模板自我复制","B、按照RNA密码子的排列顺序合成蛋白质","C、DNA以其一条链为模板合成RNA","D、DNA按照碱基互补配对原则自我复制"]
大便时溏时泻,迁延反复,食少,食后脘腹胀闷不舒,稍进油腻食物,则大便次数明显增加,面色萎黄无华,神疲倦怠,舌质淡,苔白,脉细弱。主要病机是() ["气机不利,肝失条达","泄泻日久,肾阳虚衰","脾胃虚弱,运化无权","饮食不节,宿食内停","湿热阻遏,传化失常"]
血热不会导致下列哪种月经病() ["月经先后无定期","痛经","月经先期","经间期出血","月经过多"]
关于低钾型周期性瘫痪的心电图改变,下面哪项是错误的() ["出现u波","T波低平或倒置","P-R间期和Q-T间期延长","T波高尖","ST段下降,QRS波增宽"]
肠鸣音活跃和肠鸣音减弱分别见于哪些情况?