类风湿性关节炎 (ＲＡ)是最常见的一种风湿性疾病。但临床对该病的诊断 ,特别是早期诊断仍常有难度。针对类风湿因子 (ＲＦ)对ＲＡ缺乏特异性的弱点 ,近期我们根据国外的报道 ,摸索建立了ＲＡ血清学诊断的一个新方法。即检测患者血中ＲＡ33抗体 (抗分子量为 33ＫＤ的一种胞核蛋 Rheumatoid arthritis (RA) is one of the most common rheumatic diseases. However, clinical diagnosis of the disease, especially early diagnosis is still often difficult. In view of the weakness that rheumatoid factor (RF) lacks in specificity to RA, we recently developed a new method of serological diagnosis of RA based on foreign reports. The detection of RA33 antibody in the blood of patients (anti-molecular weight of 33KD a nuclear egg