【单选题】救生艇靠泊操纵一般采用顶流以_____角度靠拢。
【单选题】_____ is the final stage of urine production occurring when the special cells of the renal tubules secrete ammonia, uric acid, and other waste substances directly into the renal tubule.
【单选题】Special cells, ____, in the epidermis produce the black pigment that gives color to the skin and protects against damage from the ultraviolet rays of the sun.
【单选题】伴有心收缩力减弱及尿量减少的休克患者应选用