YA-2型暗适应计的设计及应用

YA-2型暗适应计是依据维生素A(简称V A)缺乏病视紫质假说及色觉Purkinje现象设计的。漂白光亮度为300asb,弱光通过滤色片(最高吸收峰A=450nm)滤过,亮度为10~(-4)asb。强光漂白与暗适应计时自动控制。青年人暗适应时问正常值在50秒以内。 评价试验表明,YA-2型暗适应时间(YA-2T)与Thornton快速暗适应试验时间(Rapid Test Time简称RTT)呈对数直线相关,相关非常显著(N=48,r=0.70,P<0.001)。该仪器可做为人体V A缺乏的诊断工具,其敏感性为86％,特异性为95％,尤其适用于现场群体营养调查工作。

THE DESIGN AND APPLICATION OF YA-2 DARK ADAPTOMETER

YA-2 Dark Adaptometer was designed according to the theory of rho-dopsin and Purkinje's shift. The intensity of bleaching light was 300 asb and the test light was 10-4 asb which passed through a λ = 400nm filter. The bleaching and the dark adaptation time were automatically controlled and recorded. The normal value of dark adaptation of adults was within 50 seconds.The assessment showed that the dark adaptation time by YA-2 dark adaptometer was in close correlation with Thronton's Rapid Test Time (RTT),N = 48, r=0.70, p<0.001. The sensitivity and specificity of this dark adaptometer was 86% and 95% respectively. It can be used as a measure for detecting human vitamin A deficiency, especially suitable for field nutrition survey.