瑞典研究者报道，Merck＆Co公司的tirofiban与阿司匹林联合疗法能明显降低急性无Q波心肌梗死或不稳定型心绞痛病人的血小板聚集，而肝素却不能。在这一见期临床研究中，34例这类病人随机接受肝素，先静脉推注5000U，再连续滴注（调控到以活化部分凝血激酶时间维持在60～85秒） Swedish researchers report that combination therapy with tirofiban and aspirin at Merck & Co significantly reduced platelet aggregation in patients with acute QWI or unstable angina, whereas heparin did not. In this clinical trial, 34 patients were randomized to receive heparin at a dose of 5000 U, followed by continuous instillation (adjusted to maintain partial thromboplastin time between 60 and 85 seconds)