The yellow notice says:
To our patients,
Currently, we do not conduct the tests for radiation exposure or treat radiation exposure.
from Director of the Hospital
Independent journalist Hiroki Suzuki apparently spoke with the nurse at the reception counter of the hospital, who told him:
"We are instructed to say we don't do the tests for radiation exposure. All we can say is that people consult the local public health center. Tests for radiation exposure cannot be done without appointment. There's also an issue with the national government when it comes to radiation exposure..."
Since the first tweet on the subject, others have chimed in. The sign has been there, apparently, since right after March 11, 2011. The hospital is said to be famous for its treatment of thyroid illnesses. It could all be "baseless rumor", or it could all be true. (It's getting hard to believe that more than one year has passed since the nuclear accident.)
(H/T Hanayuu for the links)