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排序方式: 共有1343条查询结果,搜索用时 15 毫秒
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Of 613 consecutive patients with multivessel coronary artery disease (CAD) undergoing revascularization, 521 patients (85%) underwent primary management with percutaneous transluminal coronary angioplasty (PTCA). To examine long-term outcome in a series of patients often referred for coronary artery bypass graft (CABG) surgery, all patients undergoing multivessel dilations were identified for late follow-up analysis (n = 161). Mean age was 65 years; 54 patients (34%) were women. Four hundred fifty-five of 502 lesions (90.6%) were successfully dilated. Major in-hospital procedural complications occurred in 6 patients (3.7%), including death in 3 (1.9%), nonfatal Q-wave myocardial infarction in 2 (1.2%), and CABG in 1 (0.6%). Final follow-up data were available in 159 patients (99%) at a mean of 39 +/- 18 months. Including in-hospital events, actuarial 3-year survival was 93%, and 3-year infarct-free survival was 90%. At final follow-up, 143 of 146 patients alive (98%) were angina free. Crossover to CABG was required in 25 patients (16%). Repeat PTCA was performed in 67 patients (42%) (mean 1.7 PTCAs/patient, range 1 to 7). PTCA is an effective therapeutic alternative in the management of most patients with multivessel CAD requiring revascularization. A strategy using multiple repeated PTCA procedures when necessary results in prolonged infarct-free survival, with long-term freedom from angina and limited crossover to CABG. 相似文献
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AA Purmal GW Lampman EI Pourmal RJ Melamede SS Wallace YW Kow 《Canadian Metallurgical Quarterly》1994,269(35):22046-22053
Uracil DNA N-glycosylase (UDG) has been used as a model enzyme to test a novel universal approach to discriminate between two possible enzymatic mechanisms of specific site location in DNA, processive (DNA-scanning mechanism) and distributive (random diffusion-mediated mechanism). Two double-stranded concatemeric polynucleotides of defined length (440-480 nucleotides) containing deoxyuridine at either every 10th or 20th nucleotide in the DNA chain were prepared by the ligation of self-complementary 10- or 20-mer oligodeoxyribonucleotides. Incubation of these polynucleotides with Escherichia coli UDG, followed by thermal breakage of the abasic sites, formed fragments that were multiples of either the 10- or the 20-mer. Since the processive and distributive mechanisms of uracil removal by UDG would be very different, the fragment distribution, generated at each time interval during the UDG reaction, should be unique. To show this, we developed a computer model illustrating both possible mechanisms of UDG functioning. The distribution of DNA fragments experimentally generated during the time course of the UDG reaction was compared with the results of the computer programs that modeled the distributive and processive mechanisms. The data indicated that uracil removal, catalyzed by UDG, is consistent with a distributive model. 相似文献
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GR Lesser RH Osher D Whipple GW Abrams RJ Cionni 《Canadian Metallurgical Quarterly》1993,19(2):301-305
Three patients who developed anterior chamber fibrinous exudates after cataract surgery were treated with tissue plasminogen activator injected into the anterior chamber. There was prompt dissolution of the fibrinous exudates and no observed complications. When fibrinous exudates occur in high-risk patients after cataract surgery, tissue plasminogen activator provides an excellent means of clearing the fibrin. 相似文献
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