结构中有两个手性碳原子,有四个光学异构体,其中仅1R,2R(-)苏阿糖型有抗菌活性的是() ["氯霉素","链霉素","四环素","红霉素","青霉素"]
鼻腔上部的静脉可()。 ["构成克氏静脉丛","汇入颈外静脉","经筛静脉汇入颅内的静脉","经筛静脉汇入上矢状窦","经眼静脉汇入海绵窦"]
一位女病人流产后半年,近来阴道不规则出血,超声发现子宫增大,肌层回声不均匀,并可见蜂窝状无回声区,CDFI示血供增多,HCG增高。首先应考虑是() ["绒癌","部分性葡萄胎","不全流产","子宫腺肌症","子宫肌层内血肿"]
缺铁性贫血应用铁剂停药原则为()。 ["服至临床症状好转","服至血清铁蛋白>12μg/L","服至Hb正常后3~6个月","服至Hb正常后1年","服至Hb及RBC正常为止"]
卵巢赘生性囊肿主要包括:①浆液性囊腺瘤;②黏液性囊腺瘤;③皮样囊肿;④黄素囊肿() ["①②③","①③","②④","④","①②③④"]
简述溺水的救治原则。