基本解释初级骨髓腔英汉例句双语例句On the 17th day, most of the innteral cavity of cartilage cells mass gradually merged, expanded and formed primary bone marrow.诱导第17天，大多数软骨细胞集团内部腔隙融合并逐渐扩大形成初级骨髓组织。primary marrow cavity更多例句专业释义生物学初级髓腔