The product is from Chinese herbal medicine, and SheZu haperziaceae name qianceng tower grass, basically originate in hunan, zhejiang, guangxi, yunnan area, the separation from natural products get huperzine a is a kind of cholinesterase the reversible inhibitor, high selectivity, low toxicity and efficacy of time is long, etc, is by far the treatment of senile dementia international ideal drug candidates. Used for myasthenia gravis, senile memory loss and alzheimer's, youth learning disabilities and memory enhancement.
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