“the island of langerhans functional check” divides into the following several steps generally: (1) experiment should carry on between 7~11:00 am. Early 8:30 before to the hospital, and carried while convenient first time urinates 10ml to deliver in that morning examines. after (2) empty stomach seat draws blood, in 5 minutes drinks into 250ml to contain the 75g glucose syrup; Regarding the partial diabetic patient, for the reduction to the B cell's intense stimulation, may eat food 2 two about (approximately 100 grams) the steamed bun to replace the glucose; The gestational woman glucose's amount used is 100g; Child according to 1.75g/kg body weight computation, but the total quantity does not surpass 75g. (3) eats food latter 0.5 hour, 1 hour, 2 hour, 3 hours to draw blood separately the examination blood sugar. Conventional oral administration glucose tolerance experiment at the same time, in parallel determination blood sample insulin density. According to 5 blood in glucose level (when empty stomach fiducial mark is 0) draws the sugar manufacturing tolerance curve, simultaneously acts according to 5 time blood plasma insulin level to draw up the island of langerhans function curve.

　　When contracts diabetes, regardless of empty stomach blood plasma insulin level, the insulin release experiments the secretion curve to compare the average man to have obviously different, 1 diabetic insulin secretion reduces, the empty stomach blood plasma insulin level is lower than obviously normally, its background count below 5mu/L, after taking the sugar stimulation, its insulin release cannot elevate generally along with the blood sugar rises, often presents the non-peak the low and level curve, some patients cannot even determine. 2 diabetic empty stomach blood plasma insulin level may be normal, or is lower than slightly normally, but will often present the rush hours to retard, if in the clothing sugar latter 2 hour or 3 hour appearance, after assuming the secretion detention peak, will move. And the obese diabetes patient, the blood plasma insulin release curve is higher than obviously particularly normally, but is lower than the same body weight non-diabetes patient's release curve. After the feed, after insulin secretion peak, extends (2~3 hours) is 2 diabetes' characteristics.

　　Empty stomach blood plasma glucose density (FPG) between 6.1~7.0mmol/L, the oral administration glucose tolerance experiments (OGTT)2 hour blood plasma glucose density (2h-PG)<7.8mmol/L, suffers injury (IFG) for the empty stomach blood sugar. Empty stomach blood plasma glucose density (FPG)<7.0mmol/L, the oral administration glucose tolerance experiments the (OGTT)2 hour blood plasma glucose density (2h-PG) between 7.8~11.1mmol/L, is the sugar tolerance decreases (IGT).

　　The empty stomach blood sugar suffers injury (IFG) and the sugar tolerance decreases (IGT) to the human body is harmful, like cannot be under the control for a long time, then easy to have diabetes eyeground, the kidney, the nerve and other small blood vessels and the trunk pathological change. Strengthens the movement and the exercise, controls the diet, the lose weight suitably, may also coordinate the medicine intervention, may cause the patient to reverse for the completely normal person, no matter what but its development, possibly becomes the diabetic patient.

　　Smooth bears the sugar curve, its characteristic after sugar load does not see the blood sugar density to elevate by the normal form, but because the stomach evacuation retards, the small intestine malabsorption or the pituitary gland, the adrenal gland function is low. The hang-over bears the sugar curve, its characteristic the glucose density elevates suddenly for the blood plasma, the peak value appears moreover surpasses 10mmol/L early, but 2 hour blood sugar value is lower than the empty stomach level, may after the stomach excision method or serious liver disease and so on, intestinal tract rapid absorption glucose, but the liver cannot the corresponding fast ingestion glucose result. The above two kind of patients are not suitable carry on the oral administration glucose tolerance experiment, must use the intravenous injection glucose tolerance experiment.