title: Multiple forms of thymidine kinase during human development.
abstract: The developmental progression of thymidine kinase from the electrophoretically slow-migrating 'fetal' forms to the fast-migrating 'adult' form was examined in human serum and fetal liver. In fetal liver, only the fetal forms of the enzyme were present at 17 weeks' gestation. A transitional period followed in that both enzyme forms were identified and by 24 weeks only the adult form was detected in fetal liver. This same enzyme changeover pattern--fetal to transitional to adult--occurred at a later time in human serum as it took place between 30 and 40 weeks' gestation.
mesh_terms: D000328:Adult; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005312:Fetal Blood / Q000201:enzymology*; D005865:Gestational Age; D006801:Humans; D008099:Liver / Q000196:embryology / Q000201:enzymology*; D011247:Pregnancy; D013937:Thymidine Kinase / Q000097:blood / Q000378:metabolism*
chemical_list: D013937:Thymidine Kinase