第一: first; primary; foremost; fi ...骶椎: sacral; sacral vertebrae; ve ...第一骶神经: first sacral nerve骶椎: sacral; sacral vertebrae; vertebrae sacrales第二骶椎: second sacral vertebra第三骶椎: third sacral vertebra第四骶椎: fourth sacral vertebra第五骶椎: fifth sacral vertebra尖椎形骶椎: sacrum acutum腰骶椎x线摄影: radiography of lumbosacral spine腰骶椎正侧位: l-s-spine a& lat骶椎椎体静脉: sbvv第一: first; primary; foremost; first and foremost 第一号种子选手 no. 1 seeded player; 天下第一 the best in the world; 该领域学者中名列第一的人 the first among the scholars in this field; 一个两门功课都获得第一的优等生 a very fine student who took a double first; 获得第一名 win first place; get a first; win a championship; 他在班上名列第一。 he stands first in his class.; 第一夫人 the first lady (国家元首夫人); 第一副本 first authentic copy; duplicate; 第一家庭 the first family (国家元首一家); 第一宇宙速度 first cosmic velocity (物体具有每秒7.9公里的速度时, 就和地心引力平衡, 又叫环绕速度); 第一主犯 principal in the first degree第5腰椎至第1骶椎: lumbar fifth vertebra to sacral first vertebra腰和骶椎关节炎: lumbar and sacral spondylarthritis腰骶椎间盘变性: degeneration of lumbosacral intervertebral disc蝶式胸腰骶椎矫形器: knight-taylor orthosis腰骶椎融合术用于假关节: lumbosacral spinal fusion for pseudoarthrosis第一类, 第一种: first kind腰骶椎关节强直不伴脊髓病: lumbosacral spondylosis without myelopathy得第一: bear the bell第一, 主要: arch-第一,第二: first, second第一,首先: first of all第一,开始: init