What are the differences between A Nurse Practitioner and A Physicians Assistant? I know the Nurse Practitioner can have her own practice, but know little about what else she can do besides diagnose and prescribe.
APNs work autonomously as long as the MD is "reachable" in person or on phone. The APN also can prescribe RX depending on the state of certification. She/he is 'advanced' in medical teachings, diagnosing, and treating patients. PA are physician assistance, they cannot diagnose/treat without the MD reviewing the case and signing off on it. Please visit the AANP government website and you will find more information there. There are many restrictions to practice according to each state. Good Luck!
Physician Assistants are trained in the medical model and work with the supervision of a physician. They work under general supervision which means that a physician has to be available to communicate with PA in some way. In most cases they have considerable autonomy. PAs can diagnose and prescribe. Depending on the state medical act they can also own their own practice. You can find out more about PAs at AAPA: What is a PA?
You can get your questions answered at the PA forum: Physician Assistant Forum and Jobs
The principal difference IMO is in the scope of practice (defined in the medical act vs nursing act) and the education (medical vs nursing model).