纵向弛豫是指() ["T弛豫","自旋-自旋弛豫","自旋-晶格弛豫","氢质子顺磁场方向排列","氢质子逆磁场方向排列"]
新生儿败血症在病原体未明之前,宜选用的抗生素为() ["苯唑类青霉素+第3代头孢菌素","氨苄西林","苯唑类青霉素+阿米卡星","阿米卡星","万古霉素"]
20岁,未婚女性,身高150cm,第二性征发育不良,月经从未来潮,染色体核型为45,XO,该患者闭经属于() ["继发性闭经","子宫性闭经","卵巢性闭经","垂体性闭经","下丘脑性闭经"]
妊娠20周末子宫底高度在()。 ["脐下一横指","脐上一横指","脐下二横指","脐上二横指","脐下三指"]
新生儿败血症最常见的感染途径是() ["产后脐部感染","产前羊水穿刺感染","暖箱感染","产时产程延长","皮肤毛囊炎感染"]
腺嘌呤与嘌呤核苷酸分解的最终产物()腺嘌呤与鸟嘌呤核苷酸分解的共同中间产物()黄嘌呤氧化酶的竞争性抑制剂()