At the scene of a terrible road accident, a guy is laying sprawled out on the road, seemingly stone dead. The rescue workers are all around him, but can do nothing to resuscitate him. Suddenly, a young woman in a short miniskirt forces her way through the crowd.
"Let me at him, I can help him," she says.
"What can you do?" ask the rescue people. "We've tried everything to revive him, and it's too late."
"I can," says the woman. "Stand back!"
And she promptly takes off her panties, and crouches with her crotch over the man's face. Suddenly, the man coughs, splutters, and sits up.
"What did you do?" ask the rescue people, amazed.
The woman says, "Blood Transfusion."