No Physical Signs Although doctors once theorized that autism was caused by the parents' poor relationship with the child, that theory is now discredited among psychotherapists.

Epileptics rarely seemed to suffer from schizophrenia, a severe illness typically characterized by delusions and hallucinations; so doctors theorized that brain seizures were antipsychotic.

Because blood is involved in the natural transmission of West Nile - through mosquito bites - doctors have theorized that West Nile could be transmitted through transfusions and organ transplants.

The doctor couldn't find anything wrong and theorized that I might be a throwback to the original settlers, a loser in the Mendelian crapshoot.

The handprints peeled away, as the doctors had theorized, and Mary Kate came home from the hospital.

The doctors theorized that the density of pain receptors in the ear lobe might be lower than in the thumb.

In the past, the Oxford team said, some doctors theorized that for younger women, tamoxifen would cause the body's estrogens to feed the tumors.

By treating one aspect of addiction at a time, the chances of quitting might be improved, the doctors theorize.

Some doctors theorized that PPA caused strokes by raising blood pressure.

Ms. Schiavo had lost more than 100 pounds between her teenage years and the time of her collapse, and some doctors had theorized that her heart had stopped due to bulimia.