1. Doctors refer to this as secondary lactase deficiency.

2. The positive rate of lactase deficiency test was highest on the second hour when 25g or 12.5g lactose was given, and the difference was significant.

3. A similar, less severe, metabolic disorder is congenital lactase deficiency.

4. Characteristic and biological function of lactose, lactase deficiency and solving approach is expounded in this paper.

5. But the diarrhoea produced by this reaction may, in turn, cause lactase deficiency.

6. The peak volume in hydrogen expiration testing, for those with lactase deficiency and with lactose intolerance appeared in 13 year and 12 year group respectively .