Physical examinations can check for many problems, such as pre-existing diseases or sub-health states, potential cardiovascular diseases, cancer and other risks. A physical examination can check for leukemia, bacterial infections, anemia, and abnormal blood clotting through routine blood tests, and diabetes through blood glucose tests. The blood lipid test reveals the presence of hyperlipidemia, and the five tests for hepatitis B and hepatitis C antibodies are used to see if viral hepatitis is present. A lung CT test can reveal the presence of lung cancer, pneumonia, and lung nodules. Cranial MRI or cranial CT examinations can check whether there is a tumor in the brain or a series of problems such as insufficient blood supply to the brain or cerebral infarction, and electrocardiogram examinations can check whether there is insufficient blood supply to the heart muscle or myocardial infarction.