81.   Doctors and pharmacists must be registered, and patients will undergo extensive education and be routinely surveyed to make sure they are trying to prevent pregnancies.

82.   However in many of these patients a process called restenosis occurs that causes the arteries to close again and requires patients to undergo further surgery.

83.   If those tests turn up suspicious results, the patient undergoes a biopsy.

84.   If it reveals blockages, patients often undergo treatments to remove them.

85.   In some cases, patients first undergo angioplasty.

86.   In the study, the patients underwent the treatment known as chemoembolization.

87.   It can be treated with antibiotics, but patients sometimes must undergo surgery, he said.

88.   Many lung cancer patients undergo radiation therapy after surgery to treat any remaining cancer cells, although some doctors have become more selective about which patients receive radiation therapy.

89.   Many lung cancer patients undergo radiation therapy after surgery to treat any remaining cancer cells.

90.   Many patients cannot undergo potentially lifesaving marrow transplants, because no closely matched donors can be found.