Doc Church is the physician in charge, and you can purchase medical supplies, heal your wounds or get rid of your rads. There is a holotape about the Replicated Man on his desk (which you can talk to the Doc about), and the clinic medical supplies (only accessible if you kill Doc and steal the key). There is a back room which may be empty or holding one-three unconscious patients.
The key to the medical supplies case in Doc Church's Office can be found on Doc Church's corpse.
There is a holotape on top of Doc Church's desk to the left of the broken computer terminal entitled Wanted: Trustworthy Surgeon. This holotape can activate The Replicated Man quest.
Xbox 360 There is a metal box on the bottom shelf in the Megaton clinic, Located on the same wall as the entrance. When the box is searched and there are no items inside the box will never have the "[Empty]" text under the name.
If you open the "shack door" in the clinic's "lobby", the patient there sometimes stands on the bed and just sways back and forth, with no dialog options.
On rare occasions, if you kill one or more of the patients and come back, the dead patients may be alive again and standing on their beds. If you removed any of their limbs while killing them, they won't be anywhere in sight.