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stem cell – n. a simple cell in the body that is able to develop into any one of various kinds of cells (such as blood cells, skin cells, etc.)
transplant – n. medical: a medical operation in which an organ or other part that has been removed from the body of one person is put into the body of another person
anti-retroviral – adj. using a treatment with drugs that inhibit the ability of the human immunodeficiency virus (HIV) or other types of retroviruses to multiply in the body.
detect – v. to discover or notice the presence of (something that is hidden or hard to see, hear, taste, etc.)
expensive– adj. costly
