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Experience over two decades in the surgical management of pulmonary atresia with intact ventricular septum demonstrates that eventual right ventricular (RV) reconstruction is possible in the majority of patients surviving valvotomy in infancy. Ten of 17 operative survivors of early valvotomy have eventually received a patch graft to the RV outflow tract, with no reoperative deaths (mean follow-up, 7.4 years). RV systolic pressures, suprasystemic prior to reoperation, are near normal after outflow patch reconstruction. Serial cineangiograms show evidence of RV growth by measurement of tricuspid annulus diameter (TAD), and demonstrate a rate of growth [d(TAD)/d(body length)] greater than a normal rate derived from autopsy data. The mean TAD growth rate is significantly greater than that of patients with less favorable ventricle types treated with a systemic-pulmonary shunt alone. Measurement of TAD is a useful method for following RV growth, and may aid in selecting patients for RV reconstruction.  相似文献   
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Peak latency variation and the temporal interrelationships of the auditory event-related potential were investigated in 12 normal adults (ages 28-42). Measures of variation were based on both conventional averages and single trials. Estimates of N1, P2, N2 and P3 latencies were made on a trial-by-trial basis to target stimuli recorded from Fz, Cz and Pz scalp locations. Results showed that single-trial latency variability of the auditory ERP differed both among the various components and between subjects. Larger standard deviations were measured for the later N2 and P3 components than the earlier N1 and P2 components. Regression analyses between various component latencies indicated a strong covarying relationship between N2 and P3, with N2 accounting for up to 61% of the variance of P3 latency at Pz. Earlier N1 and P2 components added little to the overall prediction of either P3 or N2. For the other components, P2 accounted for 9-16% of the variance of N2, while N1 accounted for approximately 1% of the variance of N2; N1 accounted for 8-10% of the latency variation of P2. The correlations between single-trial peak latencies and RTs were positive but of low magnitude. The highest correlations between peak latency and RT were found for N2 (r = 0.33) and P3 (r = 0.24). The low correlations between the single-trial latencies of N1 and P3 suggest that the processes reflected by these components are independent and support a distinction between the earlier and the later components of the ERP. The close temporal coupling between N2 and P3 suggests that N2 may reflect cognitive properties in common to P3 in stimulus evaluation processes.  相似文献   
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J E Starr 《JAMA》1987,258(13):1730-1731
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Electroconvulsive therapy. Current concepts   总被引:1,自引:0,他引:1  
Recent developments in the practice and theory of ECT are reviewed. Indications, efficacy, and risk/benefit considerations are discussed with emphasis on the clinical utility and cost-effectiveness of increased and earlier usage of ECT in hospitalized patients. Treatment procedures are presented in some detail with listings of medical considerations, management of complications, and other applications to general hospital practice. Research on the mechanism of action, potential future developments, and some training issues are briefly discussed.  相似文献   
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Thirty-four patients with suspected common bile duct stones were randomized to undergo endoscopic cholangiography and stone removal prior to open cholecystectomy or to have open cholecystectomy, operative cholangiography, and common bile duct exploration. Sixteen underwent the first protocol, and 18 the second. Analysis of the ability to clear stones from the common bile duct, morbidity, mortality, hospital stay, length of operation, and hospital cost showed no difference in outcome between patients treated by either method. These data suggest there is neither an advantage nor a disadvantage to treating patients with suspected duct stones by precholecystectomy endoscopic cholangiography and stone removal.  相似文献   
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