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131.
AIM: To compare the effectiveness of new and 3-month-old worn brush heads in plaque removal using a rotation-oscillation-powered toothbrush. MATERIAL AND METHODS: A single examiner blinded, randomized, cross-over study was conducted in which 34 adults attended the clinic on two occasions following 48-h periods of no oral hygiene. Following plaque scoring, subjects brushed for 2 min. with either a new brush or a brush they had used for 3 months and plaque was then re-scored. Bristle wear was assessed by measuring brushing surface areas on digital images. RESULTS: The mean plaque score percentage reductions with new brush heads were not significantly different from those achieved with 3-month-old heads for total surfaces (new=38.1%; worn=37.1%; p=0.83) and approximal surfaces (new=31.3%; worn=30.8%; p=0.9). Brushing surface area increases of the 3-month-old heads ranged from 0% to 135% (mean 26.9%). Compared with new brush heads, no significant differences were found for plaque score reductions for heads with minor, moderate or marked wear. CONCLUSION: Rotation-oscillation-powered toothbrushes with 3-month-old brush heads exhibiting various degrees of wear were as effective as new brush heads in plaque removal. Bristle age and wear on a powered toothbrush may not impede the effectiveness of plaque removal.  相似文献   
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This paper describes a quasi-experimental study of a musical exercise intervention to improve the physical, cognitive, behavioral status and life satisfaction of older residents in a long-term care facility in the United Kingdom. Twenty long-term care residents from three different units (n=60) were recruited and assigned to one of three groups: a control (C) group (no intervention), an occupational therapy (OT) group (comparison group) and a music exercise group (intervention group). Assessments of physical and cognitive status were made pre-intervention and repeated at the end of the 10-week exercise program and again 10 weeks after the completion of the program. The results show that both OT and exercise participation is associated with improvement in physical and cognitive function. However, the exercise group showed significant improvement in more areas than the OT group. The functional benefits from OT and exercise were not sustainable after these activities ceased and showed significant decline 10 weeks after the end of the programs.  相似文献   
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The dense formation of abnormal scar tissue after total knee arthroplasty results in arthrofibrosis, an unfortunate sequela of inflammation. The purpose of this study was to use a validated rabbit model to assess the effects on surgically-induced knee joint contractures of two combined pharmacological interventions: celecoxib (CXB) loaded on an implanted collagen membrane, and subcutaneously (SQ) injected ketotifen. Thirty rabbits were randomly divided into five groups. The first group received no intervention after the index surgery. The remaining four groups underwent intra-articular implantation of collagen membranes loaded with or without CXB at the time of the index surgery; two of which were also treated with SQ ketotifen. Biomechanical joint contracture data were collected at 8, 10, 16, and 24 weeks. At the time of necropsy (24 weeks), posterior capsule tissue was collected for messenger RNA and histopathologic analyses. At 24 weeks, there was a statistically significant increase in passive extension among rabbits in all groups treated with CXB and/or ketotifen compared to those in the contracture control group. There was a statistically significant decrease in COL3A1, COL6A1, and ACTA2 gene expression in the treatment groups compared to the contracture control group (P < .001). Histopathologic data also demonstrated a trend towards decreased fibrous tissue density in the CXB membrane group compared to the vehicle membrane group. The present data suggest that intra-articular placement of a treated collagen membrane blunts the severity of contracture development in a rabbit model of arthrofibrosis, and that ketotifen and CXB may independently contribute to the prevention of arthrofibrosis. Statement of clinical significance: Current literature has demonstrated that arthrofibrosis may affect up to 5% of primary total knee arthroplasty patients. For that reason, novel pharmacologic prophylaxis and treatment modalities are critical to mitigating reoperations and revisions while improving the quality of life for patients with this debilitating condition.  相似文献   
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Carbon‐14 labeled linker molecule, N‐succinimidyl‐3‐maleimidopropionate was prepared for disposition studies of PEGylated biologics. Our new route started with 100 mCi of carbon‐14 labeled Potassium cyanide (KCN) to prepare 55 mCi of [1‐14C]N‐succinimidyl‐3‐maleimidopropionate, 6 in five steps. This represents a multiple of 5.5× improvement in the yield of the desired labeled product compared with our previous synthesis.  相似文献   
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