抗凝血酶Ⅲ(AT—Ⅲ)是凝血酶主要的抑制剂,它直接与凝血酶结合形成复合物而使凝血酶灭活,肝素则加速这一反应。因此AT—Ⅲ是防止机体产生高凝倾向的重要因素之一。在病理情况下,如白血病AT—Ⅲ活性的改变,DIC、血栓形成、肝肾疾病、肿瘤等血中的AT—Ⅲ水平明显下降。在国外文献已有报道,但结果不甚一致,国内报道很少。本文为了探讨急性白血病患者血中AT—Ⅲ活性的改变及其临床意义,我们对未经治疗的急性白血病患者进行了观察,报道如下: Antithrombin III (AT-III) is a major inhibitor of thrombin, which binds directly to thrombin to form a complex that inactivates thrombin, and heparin accelerates this response. Therefore, AT-Ⅲ is one of the important factors to prevent the tendency of the body to produce hypercoagulable. In pathological conditions, such as changes in the activity of AT-III leukemia, DIC, thrombosis, liver and kidney disease, tumors and other blood levels of AT-Ⅲ decreased significantly. In foreign literature has been reported, but the results are not consistent, few domestic reports. In this paper, in order to explore the changes of blood AT-Ⅲ activity in patients with acute leukemia and its clinical significance, we observed the untreated acute leukemia patients were reported as follows: