糖皮质激素类药物可用于治疗() ["原发性血小板增多症","急性淋巴细胞白血病","慢性粒细胞白血病","真性红细胞增多症","骨质疏松"]
羟基脲的抗肿瘤作用机制是() ["抑制二氢叶酸还原酶","阻止嘧啶核苷酸生成","阻止嘌呤核苷酸生成","抑制核苷酸还原酶","抑制DNA多聚酶"]
在下列何种情况,顶径不能准确显示胎儿的孕周() ["糖尿病患者妊娠","横位","多胎妊娠","首次妊娠"]
甲氨蝶呤抗肿瘤的主要机制是() ["抑制二氢叶酸合成酶","抑制二氢叶酸还原酶","破坏DNA结构和功能","嵌入DNA干扰转录RNA","干扰蛋白质合成"]
临床试验中的试验用药品是() ["不得在定点药店出售","不得在社区医院出售","不得在市场上经销","不得在社会药店出售","不得在超市出售"]
耐火度不低于1580℃的无机非金属材料称为()。