| 2. |
- Robertsson, Otto, et al.
(författare)
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Knee arthroplasty in rheumatoid arthritis. A report from the Swedish Knee Arthroplasty Register on 4,381 primary operations 1985-1995
- 1997
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Ingår i: Acta Orthopaedica Scandinavica. - 0001-6470. ; 68:6, s. 545-554
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Tidskriftsartikel (refereegranskat)abstract
- The Swedish Knee Arthroplasty Register has data on 4,381 primary operations performed 1985-1995 for rheumatoid arthritis. Of these, 192 were performed with unicompartmental prostheses and 4143 with tricompartmental. 77% were women and the mean age was 66 years. There were 126 first, 20 second, and 1 third revision in tricompartmental arthroplasties, mainly for loosening, infection and patellar problems. There were 38 first, 3 second, and 1 third revision in unicompartmental arthroplasties, mainly for progression of RA and loosening. Cumulative revision rates (Kaplan-Meier) were calculated. Tricompartmental knees had a 10-year cumulative revision rate of 5% and uni-knees 25%. Patients treated before 1990, men and patients younger than 55 had higher revision rates than patients treated after 1990, women and older patients, respectively. Cemented tibial components resulted in lower revision rates than uncemented ones. There was no significant difference in revision rates between patellar replaced and unreplaced knees or between the 9 commonest implant types.
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| 3. |
- Vesecky, S.M., et al.
(författare)
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Catalytic reduction of nitrogen oxides by methane over Pd(110)
- 1996
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Ingår i: Journal of Physical Chemistry. - : American Chemical Society (ACS). - 0022-3654 .- 1541-5740. ; 100:37, s. 15242-15246
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Tidskriftsartikel (refereegranskat)abstract
- The catalytic reduction of NO with CH4 has been studied over Pd(110) in the temperature range 700-800 K at a total pressure of 10 Torr. The rate of NO reduction is at a maximum at a high CH4/NO stoichiometry (8/1) and at a minimum at a low (1/4) CH4/NO ratio. Correspondingly, the activation energy for NO reduction decreases with increasing CH4/NO ratio, and the reaction orders are -1.0 in NO and +1.5 in CH4. Unlike NO, the rate of N2O reduction is at a maximum at low CH4 pressures, and the reaction orders are positive in N2O and negative in CH4. In the presence of oxygen, NO is oxidized to NO2, which is in turn reduced back to NO by CH4. The NO/NO2 oxidation/reduction cycle has the effect of delaying NO reduction to N2 (or N2O) until all of the O2 is consumed.
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