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The role of financial incentives in HIV care is not well studied. We conducted a single-site study of monetary incentives for viral load suppression, using each patient as his own control. The incentive size ($100/quarter) was designed to be cost-neutral, offsetting estimated downstream costs averted through reduced HIV transmission. Feasibility outcomes were clinic workflow, patient acceptability, and patient comprehension. Although the study was not powered for effectiveness, we also analyzed viral load suppression. Of 80 eligible patients, 77 consented, and 69 had 12 month follow-up. Feasibility outcomes showed minimal impact on patient workflow, near-unanimous patient acceptability, and satisfactory patient comprehension. Among individuals with detectable viral loads pre-intervention, the proportion of undetectable viral load tests increased from 57 to 69 % before versus after the intervention. It is feasible to use financial incentives to reward ART adherence, and to specify the incentive by requiring cost-neutrality and targeting biological outcomes.  相似文献   
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BACKGROUND: A recently proposed one-stage bone-transport surgical procedure exploits the intrinsic osteogenic potential of the periosteum while providing mechanical stability through intramedullary nailing. The objective of this study was to assess the efficacy of this technique to bridge massive long-bone defects in a single stage. METHODS: With use of an ovine femoral model, an in situ periosteal sleeve was elevated circumferentially from healthy diaphyseal bone, which was osteotomized and transported over an intramedullary nail into a 2.54-cm (1-in) critical-sized diaphyseal defect. The defect-bridging and bone-regenerating capacity of the procedure were tested in five groups of seven animals each, which were defined by the absence (Group 1; control) or presence of the periosteal sleeve alone (Group 2), bone graft within the periosteal sleeve (Groups 3 and 5), as well as retention of adherent, vascularized cortical bone chips on the periosteal sleeve with or without bone graft (Groups 4 and 5). The efficacy of the procedure was assessed qualitatively and quantitatively. RESULTS: At sixteen weeks, osseous bridging of the defect was observed in all twenty-eight experimental sheep in which the periosteal sleeve was retained; the defect persisted in the remaining seven control sheep. Among the experimental groups 2 through 5, significant differences were observed in the density of the regenerated bone tissue; the two groups in which vascularized bone chips adhered to the inner surface of the periosteal sleeve (Groups 4 and 5) showed a higher mean bone density in the defect zone (p < 0.02) than did the other groups. In these two groups with the highest bone density, the addition of bone graft was associated with a significantly lower callus density than that observed without bone graft (p < 0.05). The volume of regenerate bone (p < 0.02) was significantly greater in the groups in which the periosteal sleeve was retained than it was in the control group. Among the experimental groups (groups 2 through 5), however, with the numbers studied, no significant differences in the volume of regenerate bone could be attributed to the inclusion of bone graft within the sleeve or to vascularized bone chips remaining adherent to the periosteum. CONCLUSIONS: The novel surgical procedure was shown to be effective in bridging a critical-sized defect in an ovine femoral model. Vascularized bone chips adherent to the inner surface of the periosteal sleeve, without the addition of morselized cancellous bone graft within the sleeve, provide not only a comparable volume of regenerate bone and composite tissue (callus and bone) but also a superior density of regenerate bone compared with that after the addition of bone graft.  相似文献   
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