"Then—Suddenly—The Viselike Clutch Weakened and Relaxed"

"The Vanishing Ambulance."
By J. Lenivers Carew (?-?).
First appearance: Top-Notch Magazine, February 1, 1912.
Short short story (8 pages).
Online at The Pulp Magazine Project (HERE, slow-load PDF; scroll down to page 168).

When he rushes to respond to an emergency call at the city hospital, young physician Stephen Denzil doesn't have an inkling that he's about to spring a trap—with himself
as the prey . . .

Main characters:
~ The chairman:
   "This board never waits for applicants who are not prompt."
~ Doctor Denzil:
   "You made a mistake. You ignored the fact that a man who has been bought still has a price!"
~ Doctor Gilbert Gresham:
   "Hear the bell, Stephen? The bus is going out."
~ Doctor Fraser:
   "They lied to you, Denzil."
~ Pat Kelly:
   "I'm an awful bad feller when I get on the track of a man."
~ Roach:
   "Only you mustn't talk to these fellers—it wouldn't do no good, an' the doctor's a sharp one. You leave him for me to deal with."
~ Greene:
   "What do yer think I am, a doctor?"

Typo: "hosiptal"

Resources:
- Whoever J. Lenivers Carew was and whenever this individual lived are still a mystery; FictionMags credits Carew with fifteen items, ninety percent of them for Top-Notch,
and all from 1910 to 1915.

The bottom line: "I remember the time I was kidnapped and they sent a piece of my finger to my father. He said he wanted more proof."
— Rodney Dangerfield