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(EK-strakt)
![](https://webarchive.library.unt.edu/eot2008/20090514032326im_/http://www.cancer.gov/images/spacer.gif)
| In medicine, a preparation of a substance obtained from plants, animals, or bacteria and used as a drug or in drugs. |
Previous Definitions: | external radiation therapy, external-beam radiation therapy, extracorporeal photopheresis, extracranial, extracranial germ cell tumor | Next Definitions: | extragonadal germ cell tumor, extrahepatic, extrahepatic bile duct, extrahepatic bile duct cancer, extranodal |
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