Along with the rapid growth of the oldest age groups of the population, AD has become the leading neurodegenerative disorder which seriously threatens the health of the aged worldwide. The epidemiologic data indicate that AD is the neurodegenerative disease with the highest rate of incidence; and according to a conservative estimate, just in 2006, AD affected about 4.6 million new patients worldwide. Facing up to the dramatic rise in life expectancy and the devastation to human health, high treatme...