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991.
Although the back school is a popular treatment for patients with low back pain, especially in Scandinavian countries, very few well-designed studies into the effectiveness of this type of treatment have been performed. Back schools are programs in a group setting, directed toward pain management and consisting of elements of education and/or training of skills. The Maastricht Back School is designed to be a combination of all those elements about which we consider a back school should give information and training. In order to determine the effectiveness of the Maastricht Back School, we conducted a randomized trial (n = 77) comparing a group that attended back school with a waiting list control group. The most important measures of effect were pain management, pain, medical consumption, and absenteeism from work. The overall response was 85.5%. The results of an intention-to-treat analysis of the data collected 2 and 6 months after randomization consistently suggested inefficacy of the Maastricht Back School for all effect parameters (except for the effect parameter knowledge). Though the present study certainly had some limitations, we question the clinical relevancy of back schools.  相似文献   
992.
Mg(OH)2 suspensions were floated utilising sodium dodecyl sulphate (SDS) and sodium lauroyl isethionate (SLI) collectors, for rapid dewatering of radwaste suspensions. Freundlich adsorption isotherms were first used to compare the adsorption densities of SDS and SLI on Mg(OH)2 surfaces, to determine the maximum monolayer coverage capacity, and were found to be 0.11 μmol m−2 at a dosed concentration of 172 μM for SDS and 0.05 μmol m−2 at a dosed concentration of 188 μM for SLI. The natural and salt induced coagulation kinetics of Mg(OH)2 were examined using static light scattering, where the influence of collector adsorption on particle size distributions was also investigated, to probe potential hydrodynamic limitations of flotation. Particle stabilised foam formation was then characterised using a Bikerman column test, where the dynamic foamability indices (DFIs) of SDS and SLI were determined to be 49 × 103 s L mol−1 and 321 × 103 s L mol−1 respectively. Flotation performance was measured, and a collection efficiency factor used to compare the solid–liquid separation ability of mixed 2.5 vol% suspensions with SDS or SLI, as well as MIBC frother. Optimal performance aligned with collector concentrations relating to predicted maximum monolayer coverage, and whilst both surfactants were effective, SDS systems performed better than SLI in all metrics. Recoveries of >80% of the Mg(OH)2 wastes were achieved, whilst only transferring 35% of the water mass at the optimum SDS dosed concentration of 82 μM, likely due to its denser surface adsorption and minimised lamella water entrainment.

Mg(OH)2 suspensions were floated utilising sodium dodecyl sulphate (SDS) sodium lauroyl isethionate (SLI) collectors, for rapid dewatering of radwaste suspensions.  相似文献   
993.
In this study, we show that an inhibitor of glycosphin-golipid biosynthesis, D,L-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), increases the chemosensitivity of neuroblastoma tumor cells for Taxol and vincristine. At noneffective low doses of Taxol or vincristine, the addition of a noneffective dose of PDMP resulted in 70% cytotoxicity, indicating synergy. Such an effect was not observed for etoposide (VP16). PDMP caused an early (6 h) increase in ceramide (Cer) levels, but the excess Cer was metabolically removed in the long-term (96 h). However, upon incubation with PDMP in combination with Taxol, but not with etoposide, Cer levels remained elevated at 96 h. These results suggest that neuroblastoma cells are normally able to metabolically remove excess Cer, but lose this capacity upon exposure to microtubule modulating anticancer agents (Taxol or vincristine). In addition, PDMP treatment resulted in a decreased efflux of [14C]Taxol and [3H]vincristine from neuroblastoma cells, similar to treatment with PSC833 or MK571, suggesting an effect of PDMP on the transporter proteins P-glycoprotein and/or multidrug resistance protein. PDMP did not further reduce [14C]Taxol or [3H]vincristine efflux in PSC833-treated cells, although it did further diminish cell survival under these conditions. We conclude that a combined administration of nontoxic concentrations of PDMP and either Taxol or vincristine results in highly sensitized neuroblastoma cells. This appears to involve a sustained elevation of Cer levels, possibly in concert with increased drug accumulation.  相似文献   
994.
We analysed a Dutch family with autosomal dominant non-syndromic progressive sensorineural hearing loss and mapped the underlying gene defect by genetic linkage analysis to a 11.0 cM region overlapping the DFNA9 interval on chromosome 14q12-q13. Clinically, the Dutch family differs from the original DFNA9 family by a later age at onset and a more clearly established vestibular impairment. A gene that is highly and specifically expressed in the human fetal cochlea and vestibule, COCH (previously described as Coch5B2 ), was mapped to the DFNA9 critical region. Sequence analysis revealed a 208C-->T mutation in the COCH gene, resulting in a Pro51Ser substitution in the predicted protein in all affected individuals of the family but not in unaffected family members and 200 control individuals. The same mutation was also identified in three apparently unrelated families with a similar phenotype, suggesting the presence of a Dutch founder mutation. The function of COCH is unknown but several characteristics of the protein point to a structural role in the extracellular matrix. The mutant serine at position 51 is situated between cysteines and possibly interferes with proper COCH protein folding or its interaction with extracellular matrix proteins.   相似文献   
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We report here on a newborn with end-stage renal failure due to autosomal recessive polycystic kidney disease, also causing ventilation-requiring respiratory distress. Peritoneal dialysis was able to keep the newborn alive but not wean it from the respirator. After removal of both huge kidneys, dialysis became more effective and allowed the neonate to be extubated only 5 days later. It was decided to register the baby for a pediatric cadaveric kidney transplant when it reached 6 kg/body wt or to perform a living related transplant if no such kidney became available and the baby grew to 7 kg/body wt. At the age of 9 months and a weight of 6 kg a cadaveric kidney from a 20-month-old donor became available and was transplanted extraperitoneally. Prophylactic immunosuppression included cyclosporin, mycophenolate mofetil and steroids. Pneumonia on post-operative day 10 required respiratory care for several days and acute rejection requiring peritoneal dialysis. Both complications were controlled with antibiotics and conversion from cyclosporin to tacrolimus and a temporary increase in steroids. Thirteen months later the child is alive and well with a serum creatinine of 0.6 mg%. From this experience we would recommend early removal of both polycystic kidneys causing end-stage renal failure and respiratory insufficiency, starting peritoneal dialysis and performing a renal transplant as soon as possible. This therapeutic strategy seems appropriate for this complex situation.  相似文献   
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