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Experience of vascular thrombosis prophylaxis and treatment after reconstructive operation conduction on abdominal aorta and peripheral arteries in 244 patients, including 112 of them immediately after the operation, 32-up to one year time, 100-in long-term follow-up period was summarized. Main aetiological cause for thrombosis occurrence immediately after the operation were technical and tactical failures committed during its conduction, in the early postoperative period-the neointima hyperplasia in the anastomosis area, in late terms-the blood outflow disorder from the reconstructed segment due to the atherosclerosis progression. Original methods of reoperation conduction for the transplant thrombosis and the outflow arteries reconstruction were proposed. Mortality lowering from 8.8 to 5.3% and the extremity revascularization occurrence, in 75% of patients immediately after the operation and in 84%-in long-term period was promoted owing to tactics of postoperative thrombosis treatment elaborated. 相似文献
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AP Andonopoulos M Tiniakou M Melachrinou H Sfountouris A Bounas C Zervas NC Zoumbos 《Canadian Metallurgical Quarterly》1997,64(5):287-292
A prfA gene encoding polypeptide release factor RF1 was cloned from Thermus thermophilus. T thermophilus RF1 shares 68% homology with Escherichia coli RF1, and its overproduction reduced readthrough translation of UAG, not of UGA, in the lacZ gene. Rapid purification of T thermophilus RF1 was achieved by T7-RNA polymerase driven overexpression of T thermophilus RF1 protein with a C-terminal histidine tag. 相似文献
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NR Every LS Parsons SD Fihn EB Larson C Maynard AP Hallstrom JS Martin WD Weaver 《Canadian Metallurgical Quarterly》1997,96(6):1770-1775
BACKGROUND: Previous studies have documented the strong association between availability of on-site cardiac catheterization facilities and increased use of coronary angiography in patients with acute myocardial infarction (AMI). Although these studies have shown little influence of the availability of catheterization labs on hospital mortality, no long-term follow-up has been reported. METHODS AND RESULTS: From a cohort of 12,331 AMI patients admitted to 19 Seattle area hospitals, we compared long-term outcome in 7985 patients admitted to hospitals with and 4346 patients admitted to hospitals without on-site catheterization labs. During the index hospitalization, patients admitted to hospitals with on-site catheterization were more likely to undergo coronary angiography (67.1% versus 39.3%, P<.0001), coronary angioplasty (32.5% versus 13.2%, P<.0001), or coronary bypass surgery (12.5% versus 9.5%, P<.0001). At 3-year follow-up, patients admitted to hospitals with on-site catheterization labs were more likely to undergo postdischarge angiography (19.2% versus 15.2%, P=.0001) and coronary angioplasty (11.6% versus 8.2%, P<.0001). This was associated with approximately $2500.00 per patient in higher cumulative costs. Despite this higher rate of procedure use, there was no association between admission to a hospital with on-site catheterization facilities and lower long-term mortality (multivariate hazard ratio, 1.0; 95% CI, 0.93 to 1.1., the hazard being associated with admission to hospitals with on-site catheterization facilities). CONCLUSIONS: In an urban area with unconstrained patient transfer mechanisms and high overall cardiac procedure use rates, AMI patients admitted to hospitals without on-site catheterization facilities were managed with fewer procedures during hospitalization and follow-up. This more conservative treatment approach was not associated with any observed increase in long-term mortality. 相似文献
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OBJECTIVES: This report describes how the 1995 National Survey of Family Growth (NSFG) was designed, planned, and implemented. The NSFG is a national survey of women 15-44 years of age designed to provide national estimates of factors affecting pregnancy and birth rates and the health of women and infants. Planning for the 1995 NSFG began in 1990 at a formal conference with the survey's data users. Suggestions for substantial changes and improvements in the survey were made there and carried out by NSFG staff and the NSFG contractor--the Research Triangle Institute (RTI). METHODS: The survey was converted from paper and pencil interviewing to Computer-Assisted Personal Interviewing (CAPI) to improve the quality, consistency, and timeliness of the data. At the same time, event histories of the respondent's work, education, family background, cohabitation, and sexual partners were added to lend explanatory power to the survey. These changes made the interview and the CAPI program long--average interview length was 103 minutes--and complex, but the CAPI program worked very well. RESULTS: About 260 female interviewers were trained for 7 days in January 1995. These interviewers completed a total of 10,847 interviews with women 15-44 years of age, for a response rate of 79 percent. This report describes how the survey was planned and designed and how the data were collected, edited, and processed for public use. This report may be of interest to NSFG data users and to those planning other computer-assisted surveys. 相似文献
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A backstepping control design for marine vehicles was described in (Marine Control Systems: Guidance, Navigation and Control of Ships, Rigs, and Underwater Vehicles. Marine Cybernetics AS: Trondheim, Norway, 2002). Under a backstepping feedback law, global asymptotic stability of the closed‐loop system can be shown under the assumption of unlimited actuation. This paper addresses the issues that arise in the implementation of a backstepping feedback law by saturating actuators. First, for a given backstepping feedback law, an estimate of the domain of attraction is given for the resulting closed‐loop system under actuator saturation. A high gain component is then constructed and augmented to the original backstepping feedback law. This additional high gain component is shown not to shrink the estimate of the domain of attraction but to possess the ability to improve the closed‐loop response and to reject disturbance. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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