A doctor is at home when the phone rings. He answers it and hears, "Dr Epstein? This is Mansfield in Radiology. Can you come over to my house right now? We need a fourth for poker."
Epstein turns to his wife and says, "I have to go, dear. It's an emergency."
The wife look up and asks, "Is it serious?"
Epstein nods. "Yes, it is. There are three doctors there already."