extracoden.附加码extraadj.额外的n.额外之物；临时演员adv.特别地extracellular tissue细胞外组织extra-vocalization借言Extracorporeal blood体外血液extravesical orifice膀胱外输尿管开口extra-high voltage超高压电extrachromosomal dna染色体外extragalactic system河外星系extracellular factor胞外因子extracorporeal heart体外人工心extra sliding member特别滑动构件