Those originally employed were based either on the fusion of the PCE to a tumour specific antibody (Antibody-Directed Prodrug Therapy, ADEPT) or on the delivery of the gene encoding the PCE using viral or non-viral vectors (Gene-Directed Enzyme Prodrug Therapy, GDEPT).
Urea is widely used in fertilizers as a source of nitrogen and is an important raw material for the chemical industry. Friedrich WÃ¶hler's discovery in 1828 that urea can be produced from inorganic starting materials was an important conceptual milestone in chemistry.
Whether or not you buy organic, you can do your part to reduce pesticide residues on foods with the following tips: 1  Wash and scrub produce under streaming water to remove dirt, bacteria, and surface pesticide residues -- even produce with inedible skins, such as cantaloupe.  Remove the outer leaves of leafy vegetables.