胸腺嘧啶核苷激酶(TK)在DNA合成途径中,能催化胸腺嘧啶核苷至胸腺嘧啶核苷单磷酸盐的磷酸化,并以两种不同的活性出现于人体组织中.在增殖着的细胞中,这种活性被称为胎儿型,显示类似于人体胚胎组织的性质;而在正常暂时休止的细胞中,这种活性被称为成人型.作者近来证实,在由维生素B_(12)或叶酸缺乏所致贫血患者的未受刺激的 Thymidine kinase (TK), in the DNA synthesis pathway, catalyzes the phosphorylation of thymidine to thymidine monophosphate and appears in human tissues with two different activities. In proliferating cells , This activity is called a fetal type and shows similarities to the properties of human embryonic tissue, whereas in normal, temporarily resting cells, this activity is referred to as an adult type. The authors recently demonstrated that in the presence of vitamin B 12 or Folic acid deficiency caused by anemia in patients with unstimulated