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1.
The authors report the case of a 32 year old woman who was shot with a shotgun. Acute inferior wall infarction was detected fortuitously on electrocardiography and coronary angiography showed occlusion of the right coronary artery with lead shot. The single coronary lesion, absence, of other cardiac complications (haemopericardium, cardiac perforation, ...) and the favourable outcome with conservative medical treatment has not been previously reported to the authors' knowledge.  相似文献   
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Efficient conversion between the LP01 and LP11 modes in a two-mode fibre is achieved by periodically ablating the fibre surface with a CO2 laser and then annealing the fibre with an electric arc. The resulting periodic core deformation produces 99% mode conversion over a 37 nm bandwidth around 1540 nm and 0.38 dB insertion loss  相似文献   
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BACKGROUND: Upon the availability of a cadaveric donor kidney, a delicate allocation process precedes every transplantation. A remodeled Eurotransplant Kidney Allocation System (ETKAS)-derived from simulation studies-was installed in March 1996. The purpose was to adjust long waiting times and international exchange balances, while aiming at an optimal HLA-mismatch distribution. The new ETKAS consisted of a point-score system that was 100% patient oriented. METHODS: The impact of the new ETKAS on the composition of the waiting list, and the outcome of the allocation procedures during its first year, were evaluated and compared with the results obtained in 1995. RESULTS: The percentage of long-waiting patients and of patients with poorly matchable HLA phenotype increased significantly, from 9% to 19% and from 19% to 29%, respectively. Zero HLA-A-, HLA-B-, HLA-DR-mismatched patients still comprised 23% of the kidney transplant activity. The kidney exchange of the different Eurotransplant countries became balanced within 4 months; this persisted during the rest of the year. Pediatric patients had a high transplantation rate due to an assignment of extra points. The composition of the waiting list showed, after 1 year, fewer long-waiting patients and fewer patients with rare HLA phenotypes. CONCLUSIONS: The new ETKAS was able in its first year to meet the goals set at its introduction. In comparison with the old ETKAS, there was a better trade-off between HLA matching and waiting time. The value of computer simulation studies has been demonstrated impressively in the context of organ allocation.  相似文献   
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The mechanical properties of metal fibre porous structures were studied in the light of their potential application as surface coatings of implants. Stainless steel AISI 316 L fibres with diameters of 50 and 100μm were compacted and sintered. The variation of the modulus of elasticity with density, as obtained in tension, corresponds closely with theoretical models. The ultimate failure of the tensile specimens proceeds through the fibres, and not through the sinter bonds, except at lower densities. Differences in yield strength between 50 and 100 μm fibre tensile specimens are explained on the basis of the onset of plastic deformation of the individual fibres. Upon compression the modulus of elasticity is nearly 10 times smaller than in tension. This result is due to the different deformation patterns of the fibres in compression and tension.  相似文献   
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The present study deals with an X-ray diffraction analysis of U3Si. The U3Si lattice parameters have been determined to a more accurate degree by means of a counter diffractometer step-scan apparatus. The intensities of the reflections were also recorded and compared with the calculated values. The discrepancies between calculated and observed intensités are discussed; they are probably caused by periodic faulting.  相似文献   
7.
A multifrequency waveguide grating laser by selective area epitaxy   总被引:4,自引:0,他引:4  
We demonstrate a 6 frequency digitally tunable laser based on a waveguide grating router fabricated using selective area epitaxy (SAE). The laser wavelengths span from 1.527 to 1.557 μm with 6.4 nm spacings. The bandgap variation in the active layer plane is from 1.352 μm for waveguide ribs to 1.605 μm for the amplifiers. ASE noise is suppressed by 35 db. These results demonstrate the flexibility of SAE technology for building complete photonic circuits  相似文献   
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