钢轨组放在道心时,距线路上的旧轨净距离不小于()。
()是一种可再生资源 ["气候资源","石油","煤炭"]
青春期后促使骨骺愈合的激素是() ["雌激素","孕激素","雄激素","PRL","抑制素"]
过高可引起闭经的激素是() ["雌激素","孕激素","雄激素","PRL","抑制素"]
患者,男,15岁,反复发作肉眼血尿。感染后加重,无水肿、高血压及肾功能减退,最可能的诊断是() ["泌尿系统肿瘤","急性肾小球肾炎","慢性肾小球肾炎","IgA肾炎","急进性肾小球肾炎"]
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