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991.
VDD pacing follow-up is similar in pediatric and adult patients. Atrial and ventricular pacing parameters are stable during 2-year follow-up in children, and single-pass lead VDD pacing is recommended when the sinus node function is normal.  相似文献   
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994.
Report of an International Conference held by RILEM and organized by the CSIRO Division of Building. Construction and Engineering, Melbourne, and the Australian Concrete Repairs Association, Melbourne, in cooperation with RILEM Technical Committee TC 124 ‘Repair Strategies for Concrete Structures Damaged by Steel Corrosion’.  相似文献   
995.
This study focused on the self-representations of suicidal adolescent. Twenty-six Israeli suicidal inpatients, 24 nonsuicidal inpatients, and 24 control participants completed scales on suicidal tendencies, the hedonic value of self-representations, the complexity (differentiation, integration) of these self-representations, and the discrepancies among self domains (actual, ideal, ought). Suicidal adolescents showed more negative self-representations, a less differentiated and less integrated organization of self-attributes, and more discrepancies between the 3 assessed domains of the self than did control participants. In addition, compared with psychiatric nonsuicidal participants, suicidal adolescents showed a less complex organization of self-attributes and a higher discrepancy between ideal self and ought self. Results were discussed in terms of the vulnerable self of suicidal adolescents, characterized by uneven processing of positive and negative information, confusion, and simplicity.  相似文献   
996.
The clinical and pathological findings of a 43-year-old woman, diagnosed as having acute hemorrhagic leukoencephalitis at postmortem examination, are presented. The acute hemorrhagic leukoencephalitis affects mainly young adults and is the most fulminant from of demyelinating disease. It is frequently preceded by a respiratory infection. Diagnosis is facilitated by CT scanning and MRI, which reveal the massive lesion in the cerebral white matter. Many cases terminate fatally in 2 or 4 days, but in others survival is longer. The pathological findings are distinctive.  相似文献   
997.
Optimized stent expansion by high-pressure inflations of oversized balloons has initially been derived from experience obtained with the Palmaz-Schatz stent, whereas there is little experience with this strategy in the Wallstent. By using this approach with quantitative coronary angiographic guidance, 20 Wallstents and 20 Palmaz-Schatz stents were implanted in 34 patients and consecutively examined by conventional two-dimensional (2D) intracoronary ultrasound (ICUS) and three-dimensional (3D) ICUS on the basis of the application of a pattern recognition algorithm. Ultrasound criteria of adequate stent expansion were defined as a complete apposition of the stent to the vessel wall, a stent symmetry index (SSI = minimum/maximum lumen diameter) > or = O.7, and a stent-reference lumen area ratio (SRR = Minimum intrastent lumen area/Average of proximal and distal reference lumen area) > or = O.8. In all cases a smooth angiographic lumen and a negative diameter stenosis, on the basis of a distal reference, was achieved. For the Wallstents ICUS showed a higher SSI (2D, 0.95 +/- 0.04 vs 0.85 +/- 0.09; p < 0.001; 3D, 0.90 +/- 0.09 vs 0.82 +/- 0.11, p < 0.05) and a lower SRR (2D, 0.66 +/- 0.12 vs 0.81 +/- 0.13, p < 0.005; 3D, 0.63 +/- 0.14 vs 0.74 +/- 0.15, p < 0.05) than for the Palmaz-Schatz stents. Ninety percent of failure in meeting these criteria resulted from a low SRR. The incidence of incomplete stent apposition (one in both stents) or SSI <0.7 was low and generally associated with an SRR <0.8. The Wallstents met the ICUS criteria less often (2D, 2(1O%) vs 10(50%), p < 0.01; 3D, 3(15%) vs 9(45%), p < 0.05), were significantly longer (35.1 +/- 7.7 mm and 14.3 +/- 3.3 mm, p < 0.0001), and generally demonstrated a larger vessel tapering, measured as proximal minus distal ICUS reference lumen area (1.33 +/- 2.91 mm2 vs 0.44 +/- 1.97 mm(2), not significant). Wallstents meeting the ICUS criteria, however, showed less vessel tapering (0.18 +/- 1.64 mm(2)). Thus optimized stent expansion was followed by excellent angiographic results for both Palmaz-Schatz and Wallstent. Although angiographic results and visual assessment of the ICUS examination suggested a good outcome, few Wallstents met the ICUS criteria in contrast to the Palmaz-Schatz stents. The low value of the SRR in the Wallstents is likely to be caused by vessel tapering, suggesting that this criterion may be unsuitable in assessing the adequacy of the expansion of relatively long stents such as the Wallstent.  相似文献   
998.
We describe a novel "see-through" indium-tin-oxide contact on the n-side of a high power unstable resonator semiconductor laser (URSL) that allows direct observation of the cavity during high power operation. Under optimized annealing conditions this transparent ITO contact has a low enough specific contact resistivity to permit normal high power CW operation of the URSL and allows the observation of filamentation. This contact scheme is applicable to a wide range of semiconductor lasers and is especially appropriate for high power devices. The same structure can also be used to obtain a 2-D thermal map of the laser cavity.  相似文献   
999.
A new type of fiber laser modelocking is examined where a phase modulator is driven asynchronously with respect to a harmonic of the roundtrip cavity frequency. An asynchronous drive is able to produce high repetition rate (>1 GHz) soliton pulses that are shorter than the classic, active modelocking pulse width limit. It is shown that with a proper choice of fiber parameters, noise cleanup and soliton pulse shaping can be obtained using filtering and asynchronous phase modulation. Limits of asynchronous detuning are derived and a comparison with the parameters ranges for synchronous phase modulation is also presented  相似文献   
1000.
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