Complex sentence: Dextran is a complex, branched glucan (polysaccharide) made of many glucose molecules joined into chains of varying lengths (from 10 to 150 kilodaltons), used as an antithrombotic (anti-platelet), and to reduce blood viscosity.
Split into simpler sentences: Dextran is a complex, branched glucan (polysaccharide made of many glucose molecules) composed of chains of varying lengths (from 10 to 150 kilodaltons). It is used medicinally as an antithrombotic (anti-platelet), and to reduce blood viscosity.