Biological roles of the elements

在自然界中，镭可以在铀矿和钍矿中做為衰變產物痕量生成，但每吨沥青铀矿中只有七分之一克镭。镭对生物（英语：Biological roles of the elements）并非必需，且由于其放射性和反应性，进入生物体内可能危害健康。目前镭除了用于核医学以外基本没有商业用途。镭曾在辐射发光

1038/nature06947. （原始内容存档于2018-10-02）.  Dunn, Katherine L.; Davie, James R. The many roles of the transcriptional regulator CTCF. Biochemistry and Cell Biology =

B1 elements to impart their repressive role (Mariner & Walters 2008). The abundance and distribution of Alu elements and similar repetitive elements throughout

Palaestina: The Mammals of Palestine. The Palestinian Biological Bulletin. 2006, (55): 1–46.  McKenna MC, Bell SK. Classification of Mammals Above the Species

（原始内容 (PDF)存档于2012-02-08）.  Hagmann, W. K. The Many Roles for Fluorine in Medicinal Chemistry. Journal of Medicinal Chemistry. 2008, 51 (15): 4359–4369