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Description
The study doesn't say what recommended B12 levels should be, just that its possible some people aren't getting enough, and that more research is needed in this area to figure out optimal levels

Effects of short term administration of recombinant human growth hormone to elderly people

Cerebral phaeohyphomycosis in an immunodeficient child treated medically with combination antifungal therapy

Retinal oxidative stress induced by high intraocular pressure
