P/F ratio: PaO2 (arterial oxygen tension) / FiO2 (fraction of inspired oxygen), COPD: Chronic obstructive lung disease, CKD: chronic kidney disease, CRP: C-reactive protein, WBC: white blood cell, SOFA: Sequential (Sepsis-related) organ failure assessment, IVC: inferior vena cava, AP/T: anteroposterior/transverse, CT: computed tomography. The gene discussed is CRP; the disease is chronic obstructive pulmonary disease.