alpha fetoprotein levels normal rangealpha fetoprotein rangeserum alpha fetoprotein normal rangenormal alpha fetoproteinalpha 1 antitrypsin medicationalpha 1 antitrypsin infusionalpha 1 antitrypsin therapyalpha fetoprotein reference rangenormal alpha fetoprotein levelalpha fetoprotein normal valuealpha one treatmentafp alpha fetoprotein normal range