每日一题_2022.11.17

A 79-year-old man presents to his family phy- sician for an annual physical examination. He denies chest pain, dyspnea, fevers, or chills. He suffered a myocardial infarction five years ago. He is taking aspirin, lisinopril, and metoprolol. His ECG is shown in the image. He is admitted to the hospital for therapy consisting of rate control and anticoagulation. After successful in-patient treatment, he is discharged with new medicines. Which of the following is the mechanism of the anticoagulant used in the long-term therapy of this patient’s condition?

一名79岁的男性到他的家庭医生那里进行每年一次的体格检查。否认胸痛、呼吸困难、发热、寒战。他五年前患了心肌梗塞。他正在服用阿司匹林、赖诺普利和美托洛尔。图像中显示了他的ECG。患者入院接受心率控制和抗凝治疗。在成功的住院治疗后，他出院并接受新药治疗。以下哪一项是该患者疾病长期治疗中使用的抗凝剂的作用机制？

(A) Activation of antithrombin III 激活抗凝血酶 III

(B) Antibody to tumor necrosis factor-a 肿瘤坏死因子抗体 A

(C) Inhibition of γ-carboxylation of vitamin K-dependent clotting factors 抑制维生素 K 依赖性凝血因子的γ-羧化

(D) Inhibition of cyclooxygenase 抑制环氧合酶

(E) Inhibition of the ADP pathway of thrombus formation 抑制血栓形成的 ADP 途径

答案解析：

该患者患有房颤，表现为 ECG 上无 P 波，这使其发生附壁血栓形成和栓塞并发症的风险更高。华法林是首选的抗凝剂。华法林抑制-其对维生素 K 依赖性凝血因子II、VII、IX和 X 以及蛋白 C 和 S 的γ-羧化，用于长期抗凝。口服，半衰期长。测量抗凝程度后必须测量国际标准化比值 (INR)。

正确答案：C