(IP 
  (NP-SBJ 
    (-NONE- *pro*))
                    
  (VP 
    (VP 
      (ADVP 
        (AD 往往))
                    
      (VP 
        (VV 要)
                    
        (VP 
          (LCP-OBJ 
            (IP 
              (NP-SBJ 
                (NN 肾脏))
                    
              (VP 
                (VP 
                  (VRD 
                    (VV 损伤)
                    
                    (VV 到))
                    
                  (NP-OBJ 
                    (JJ 相当)
                    
                    (NN 程度)))
                    
                (PU ，)
                    
                (VP 
                  (ADVP 
                    (AD 甚至))
                    
                  (ADVP 
                    (AD 只))
                    
                  (VP 
                    (VV 剩下)
                    
                    (NP-OBJ 
                      (QP 
                        (CD 四分之一))
                    
                      (NP 
                        (NN 功能)))))))
                    
            (LC 时)))))
                    
    (PU ，)
                    
    (VP 
      (ADVP 
        (AD 才))
                    
      (VP 
        (VV 能)
                    
        (VP 
          (PP-DIR 
            (P 由)
                    
            (LCP 
              (NP 
                (NN 血液))
                    
              (LC 中)))
                    
          (VP 
            (VRD 
              (VV 检验)
                    
              (VV 出来))))))))
arg1: 
                    肾脏 
                
arg2: 
                    相当 程度