Poller L, Barrowcliffe T W, van den Besselaar A M, Jespersen J, Tripodi A, Houghton D
ECAA, Department of Pathological Sciences, The University of Manchester, UK.
Thromb Haemost. 1998 Jan;79(1):122-8.
Establishing the mean normal prothrombin time (MNPT) from fresh samples for prothrombin ratios and INR often presents difficulty in selection and collection of donors. A set of seven lyophilized normal plasmas has therefore been prepared at the ECAA Central Facility and studied at 143 laboratories in sixteen European states using coagulometers in serial field exercises. All centres tested either the high ISI ECAA rabbit or low ISI ECAA human reference thromboplastin. The MNPT of fresh plasmas and means of the lyophilized samples were closely comparable with most routine rabbit thromboplastins. Using human thromboplastins means with the lyophilized normals were marginally but significantly longer and with the bovine Thrombotest significantly shorter than the MNPT of fresh plasmas causing alterations in INR. There was no appreciable effect on INR of 2.5 and 3.5 when lyophilized normals were substituted for fresh normals with the rabbit reagents.
从新鲜样本中确定凝血酶原比值和国际标准化比值（INR）的平均正常凝血酶原时间（MNPT），在供体的选择和采集方面常常存在困难。因此，欧洲共同体动物生产协会（ECAA）中央实验室制备了一组七份冻干正常血浆，并在16个欧洲国家的143个实验室中，通过连续现场操作使用凝血仪进行了研究。所有中心均检测了高国际敏感度指数（ISI）的ECAA兔源或低ISI的ECAA人源参比凝血活酶。新鲜血浆的MNPT以及冻干样本的均值与大多数常规兔源凝血活酶密切可比。使用人源凝血活酶时，冻干正常样本的均值略长但显著长于新鲜血浆的MNPT，而使用牛源凝血酶检测法时则显著短于新鲜血浆的MNPT，这导致INR发生改变。当用兔试剂将冻干正常样本替代新鲜正常样本时，对2.5和3.5的INR没有明显影响。
