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Background
Differences in outcomes have previously been reported between urban and rural settings across a multitude of chronic diseases. Whether these discrepancies have changed over time, and how sex may influence these findings is unknown for patients with ambulatory heart failure (HF). We examined the temporal incidence and mortality trends by geography in these patients.Methods and Results
We conducted a retrospective cohort study of 36,175 eastern Ontario residents who were diagnosed with HF in an outpatient setting from 1994 to 2013. The primary outcome was 1-year mortality. We examined temporal changes in mortality risk factors with the use of multivariable Cox proportional hazard models. The incidence of HF decreased in women and men across both rural and urban settings. Age-standardized mortality rates also decreased over time in both sexes but remained greater in rural men compared with rural women.Conclusions
The incidence of HF in the ambulatory setting was greater for men than women and greater in rural than urban areas, but mortality rates remained higher in rural men compared with rural women. Further research should focus on ways to reduce this gap in the outcomes of men and women with HF. 相似文献To evaluate the potential of conventional glass ionomer cement (GIC), Biodentine™, MTA, and Portland cement to induce mineral density changes in carious dentin compared to zinc oxide eugenol control cement (ZOE).
Materials and methodsFifty blocks of bovine root dentin were prepared and a biofilm model using ATCC strains of S.mutans, S.sobrinus, and L.casei was used to promote artificial dentin lesions. After demineralization, the blocks were randomly divided into the five cement groups. Half of the surface of each specimen received the tested material and the other half was covered with wax (control). Samples were stored in phosphate buffered saline solution for 30 days and after that were scanned in a micro-CT with standardized parameters. Dentin mineral density changes were calculated using differences in plot profiles of the exposed and control carious dentin. Friedman’s test, followed by Wilcoxon signed-rank test was used with 5% significance.
ResultsMean ΔZ values for the cements were 48.63 ± 19.09 for the control (ZOE), 63.31 ± 32.59 for Biodentine™, 114.63 ± 72.92 for GIC, 109.56 ± 66.28 for MTA, and 106.88 ± 66.02 for Portland cement. All cements showed a statistically significant increase in ΔZ values compared to the control, but Biodentine™ values were statistically significantly lower compared to GIC and the other calcium silicate cements.
ConclusionsTested materials present potential to induce mineral density changes in carious bovine dentin. MTA, Portland, and GIC showed higher bioactivity potential than Biodentine™.
Clinical relevanceBased on minimally invasive concept, materials with remineralization potential can be used to preserve diseased but still repairable dental tissue.
相似文献