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Abciximab appears to lower the risk of heart attack, death, and additional angioplasty in patients undergoing angioplasty to open clogged coronary arteries. Abciximab is a monoclonal antibody that blocks platelet aggregation, which is one of the steps in blood clot formation. A 2- to 3-year follow-up of 2,099 patients who were given abciximab or placebo during angioplasty found that abciximab significantly reduced the rate of heart attack, death or additional angioplasty. This is important because many patients treated with angioplasty often experience a recurrence of atherosclerosis., Context. -- Abciximab, a monoclonal antibody fragment against the platelet receptor [alpha.subllb.beta.sub.3] integrin, prevents platelet aggregation. A randomized, placebo-controlled study showed that abciximab improves outcomes for patients undergoing percutaneous coronary angioplasty at 30 days and at 6 months. Objective. -- To determine whether abciximab improves outcomes 3 years after coronary angioplasty. Design. -- Double-blind, placebo-controlled, randomized trial. Setting. -- a total of 56 academic and community hospitals in the United States. Patients. -- a total of 2099 high-risk patients undergoing coronary angioplasty were randomized. Sufficient time elapsed for 2.5 years of follow-up among 2001 patients and for 3 years of follow-up among 1599 patients. Interventions. -- abciximab bolus of 0.25 mg/kg followed by infusion at 10 [mu]g/min for 12 hours; abciximab bolus of 0.25 mg/kg followed by placebo infusion; or placebo bolus followed by placebo infusion. Main Outcomes Measures. -- The primary outcome was the composite of death, myocardial infarction, or coronary revascularization. Secondary outcomes were death, myocardial infarction, or coronary revascularization individually. Subgroups having. refractory unstable angina or evolving myocardial infarction and having different elevations of creatine kinase during initial angioplasty were analyzed. Results. -- at 3 years, composite end points occurred in 41.1% of those receiving abciximab bolus plus infusion; 47.4% of those receiving abciximab bolus only; and 47.2% of those receiving placebo only (for abciximab bolus plus infusion vs placebo, P=.009). Death occurred in 6.8%, 8.0%, and 8.6%, respectively (for abciximab bolus plus infusion vs placebo, P=.20); myocardial infarction in 10.7%, 12.2%, and 13.6%, respectively (for abciximab bolus plus infusion vs placebo, P=.08); and revascularization in 34.8%, 38.6%, and 40.1%, respectively (for abciximab bolus plus infusion vs placebo, P=.02). Among those with refractory unstable angina or evolving myocardial infarction, death occurred in 5.1%, 9.2%, and 12.7%, respectively (for abciximab bolus plus infusion vs placebo, P=.01). Death rates increased as periprocedural creatine kinase levels increased. Conclusions. -- abciximab bolus with infusion given at the time of coronary angioplasty improves outcomes as long as 3 years after the procedure. JAMA. 1997;278:479-484

This paper concerns the practically important problem of multi-category radio frequency identification (RFID) estimation: given a set of RFID tags, we want to quickly and accurately estimate the number of tags in each category. However, almost all the existing RFID estimation protocols are dedicated to the estimation problem on a single set, regardless of tag categories. A feasible solution is to separately execute the existing estimation protocols on each category. The execution time of such a serial solution is proportional to the number of categories, and cannot satisfy the delay-stringent application scenarios. Simultaneous RIFD estimation over multiple categories is desirable, and hence, this paper proposes an approach called simultaneous estimation for multi-category RFID systems (SEM). SEM exploits the Manchester-coding mechanism, which is supported by the ISO 18000-6 RFID standard, to decode the combined signals, thereby simultaneously obtaining the reply status of tags from each category. As a result, multiple bit vectors are decoded from just one physical slotted frame. Built on our SEM, many existing excellent estimation protocols can be used to estimate the tag cardinality of each category in a simultaneous manner. To ensure the predefined accuracy, we calculate the variance of the estimate in one round, as well as the variance of the average estimate in multiple rounds. To find the optimal frame size, we propose an efficient binary search-based algorithm. To address significant variance in category sizes, we propose an adaptive partitioning (AP) strategy to group categories of similar sizes together and execute the estimation protocol for each group separately. Compared with the existing protocols, our approach is much faster, meanwhile satisfying the predefined estimation accuracy. For example, with 20 categories, the proposed SEM+AP is about seven times faster than prior estimation schemes. Moreover, our approach is the only one whose normalized estimation time (i.e., time per category) decreases as the number of categories increases. [ABSTRACT FROM PUBLISHER]