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101.
BACKGROUND: Although the short-term and long-term beneficial effects of early coronary revascularization by primary PTCA or thrombolytic therapy have been established for acute myocardial infarction, thrombolytic therapy >24 hours after the onset of acute myocardial infarction has not been shown to improve clinical outcome. The purpose of this study was to assess the effect of late revascularization by primary PTCA over a 5-year period. METHODS AND RESULTS: Eighty-three patients with initial Q-wave anterior myocardial infarction >24 hours after onset were randomized into a PTCA group (n=44) and a no-PTCA group (n=39). Long-term follow-up was conducted with regard to end points, which included cardiac death, nonfatal recurrence of myocardial infarction, and development of congestive heart failure. Left ventricular ejection fraction and regional wall motion at 6 months after myocardial infarction were similar in the 2 groups. Left ventricular end-diastolic and end-systolic volume indexes were significantly smaller in the PTCA group than in the no-PTCA group (P<0.0001). With cardiac events as end points, a 5-year Kaplan-Meier event-free survival analysis revealed that the no-PTCA group had a worse prognosis than the PTCA group (P<0.0001). Patency of the infarct-related artery, left ventricular ejection fraction, end-diastolic volume index, and end-systolic volume index were significantly associated with cardiac events by a Cox proportional hazards analysis (hazard ratios 0.120, 0.845, 1.065, and 1.164, respectively). CONCLUSIONS: In initial Q-wave anterior myocardial infarction, we conclude that even with late reperfusion, PTCA had beneficial effects on cardiac events over the 5-year period after myocardial infarction, with the prevention of left ventricular dilation after myocardial infarction being a possible mechanism.  相似文献   
102.
Flue gases from a hazardous waste incinerator have been sampled in three campaigns, before and after, an oxidative acid wet scrubber working with the MercOx‐process. A continuous emission monitor for mercury speciation was used before the scrubber in the first campaign. In all campaigns, impingers with KCl and KMnO4 were used. A solid adsorption method was used in the last campaign. The mercury leaving the scrubber is oxidized at > 90 % efficiency (independent of the inlet speciation). A substantial decrease in the redox potential of the scrubber liquid caused an increased fraction of elemental gaseous mercury to be present in the clean gas. The measurements also show that the scrubber has the ability to readily absorb mercury peaks. During one extreme peak of 3,600 μg/m3 (dry gas) in the raw gas, the removal efficiency was above 99.9 %.  相似文献   
103.
104.
In this study, the chemical states of chromium (Cr), arsenic (As), and selenium (Se) in sewage sludge incineration ash were determined by X-ray absorption fine structure (XAFS) spectroscopy. Sewage sludge incineration ash was sampled from several facilities, and XAFS measurements were carried out with a beam line BL01B1 at the SPring-8 facility. Cr K-edge X-ray absorption near-edge structure (XANES) spectra suggested that Cr compounds were predominantly speciated as Cr(III) and the fraction of Cr(VI) was very minor. Compared to the reference materials, Cr XANES spectra of the incineration ashes were similar to those of FeCr2O4, Cr(OH)3, and CaCr2O4. As K-edge XANES spectra indicated that As(V) compounds were present in incineration ashes. Because the chemical state of As in sewage sludge was As3+ in our previous study, we speculated that the chemical state of As changed into As(V) during the incineration process. According to Se K-edge XANES spectra, Se compounds were predominantly Se(IV), and a slight difference was observed in the chemical states amongst facilities using inorganic or organic coagulants in the dewatering process.  相似文献   
105.
An ultralight, flexible a-Si solar cell fabricated on a polyimide film substrate has been developed. It was found that prebaking the polyimide film substrate improved the output performance of the cell by reducing the amount of H20 and polymers released from the substrate. Also, using an i-layer fabricated at high temperature (250°C) and a p-layer fabricated at low temperature (80°C) improved the cell's output performance to a level of over 10%. A maximum output of 782.4 mW and a power-to-weight ratio of 340 mW/g were obtained for an integrated-type flexible a-Si solar cell submodule with a size of 113 mm × 120 mm.  相似文献   
106.
BACKGROUNDS/AIMS: Balloon-occluded retrograde transvenous obliteration (B-RTO) has become a new treatment option for gastric varices. In the present study, mid-term follow-up data after B-RTO were presented, and the role of magnetic resonance imaging (MRI) and MR-portography in the assessment of therapeutic effect was evaluated. METHODOLOGY: Twelve patients with gastric varices were treated with up to three sessions of B-RTO. The patients were followed up with MRI, MR-portography, and endoscopy for a mean of 12.3 months. RESULTS: In ten patients, one (n = 8) or two (n = 2) sessions of B-RTO were effective to produce immediate (< 2 weeks) variceal obliteration on MRI and MR-portography. Endoscopic confirmation of variceal eradication was obtained within three (n = 9) or six (n = 1) months after B-RTO in these patients. The remaining two patients who underwent three sessions of B-RTO showed only a significant reduction in variceal size immediately after B-RTO, but variceal obliteration was observed within three months with subsequent variceal eradication. There were no signs of exacerbation of gastric varices on MRI and endoscopy in any patient during the follow-up period. CONCLUSIONS: The results suggest that B-RTO is effective for the treatment of gastric varices. MRI and MR-portography may provide accurate assessment of therapeutic effect.  相似文献   
107.
Side flow on a flood plain from a side outlet of the main channel is investigated both theoretically and experimentally for supercritical main flow. The side outlet as a model simulates a failure of a river bank in a prototype. The discharge ratios of the side outflow to that of the main channel flow, the water depth, and the velocity at the side outlet are obtained. The theoretical discharge ratio is a function of the Froude number of the main channel flow. The theoretical spreading angle of the side flow and the theoretical relationship between the velocities and the distance from an upstream point of the side outlet are also compared and predicted. All the theoretical results are found to be in good agreement with the experimental data.  相似文献   
108.
Serratia marcescens has emerged in the last few years as an important nosocomial pathogen. Many methods for typing this organism have been described. In this study the random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) was shown to be a convenient typing method for S. marcescens. Different combinations of primers previously used for typing other gram-negative bacilli were assessed. The combination of primer HLWL-74 and 1254 gave distinguishable patterns for different serotypes and proved to be the most satisfactory. By applying this combination to 175 isolates of S. marcescens, which could be classified into 38 groups on the basis of serotyping and phage typing, 73 different RAPD patterns with good reproducibility were obtained. This is, to our knowledge, the first application of the method to a large collection of S. marcescens representing a wide range of serotypes.  相似文献   
109.
As an attempt to associate a real number with a language, entropies of languages are computed by Banerji, Kuich, and others. As mappings from languages to real numbers, in this paper, measures over languages are presented. These measures satisfy additivity while entropies do not. Two kinds of measures, p-measure and ω-measure, are defined, and the computing method of these measures is shown for regular languages and context-free languages. Some properties of these measures are applied to show the nonregularity of several languages.  相似文献   
110.
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