Present doctor turned up in case (6)
I believe the answer is:
submit
'present' is the definition.
(submitting is a kind of presenting)
'doctor turned up in case' is the wordplay.
'doctor' becomes 'mb' (Bachelor of Medicine, Medicinae Baccalaureus).
'turned up' shows that the letters should be reversed in order.
'in' indicates putting letters inside.
'case' becomes 'suit' ('suit' can be a synonym of 'case').
'mb' in reverse letter order is 'bm'.
'bm' put within 'suit' is 'SUBMIT'.
(Other definitions for submit that I've seen before include "Yield (to superior force)" , "Yield to the control of another" , "Give in to another's wishes" , "Refer for judgement or consideration" , "Present (an application)" .)