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The prevention of mother-to-child HIV transmission (PMTCT) is a complex challenge in heavily affected and resource-limited settings such as South Africa. Management of PMTCT requires a cascade of interventions that need to be addressed to effectively decrease the risk of HIV transmission to infants. This PMTCT cascade includes incremental components that can be shaped and influenced by the patient-provider relationship. The relationship that a pregnant woman has with her care providers may possibly affect decisions that she makes concerning her antenatal care and may, in turn, influence the quality of the care provided. A patient-provider relationship scale (PPRS) was developed in Pretoria, South Africa with two aims: first, to quantify the patient-provider relationship in an antenatal population in a resource-limited setting and provide preliminary evidence of its reliability and validity; and second, to determine whether the patient-provider relationship has an effect on PMTCT. The instrument was administrated in a cross-sectional pilot study to a group of women at discharge after delivery (n=192) at two major hospitals in South West Tshwane. Statistical analysis of the instrument showed high reliability (α=0.91) and preliminary evidence of its validity including significant associations with participants' attitudes regarding the functioning of the clinics and a single statement (the clinic staff "know me as a person," R=0.47, p<0.001) that has been shown previously to have a significant association with adherence to antiretroviral treatment. For HIV-positive participants, the PPRS was significantly associated with statements related to important components of the PMTCT cascade. In addition, those with substantially inadequate antenatal care (≤2 visits) and those who did not initiate highly active antiretroviral therapy, although eligible, had significantly poorer PPRS scores. The PPRS is a potentially useful, context-appropriate instrument that could have an important role in future research focused on improving PMTCT and decreasing the risk of HIV infection in children.  相似文献   
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ABSTRACT: BACKGROUND: Peginesatide is a peptide-based erythropoiesis-stimulating agent that was designed and engineered to stimulate specifically the erythropoietin receptor dimer that governs erythropoiesis. The primary objective of this phase 2 dose-finding study was to determine the once-monthly peginesatide dosing strategy that would maintain hemoglobin within [PLUS-MINUS SIGN]1.0 g/dL of baseline values after conversion from epoetin alfa; the safety of peginesatide was evaluated concurrently. METHODS: Chronic hemodialysis patients on stable regimens of epoetin alfa were sequentially assigned to cohorts that differed on (1) how the peginesatide starting dose was determined (using a single epoetin alfa--to-peginesatide dose conversion ratio or a tiered, weight-based or absolute-dose conversion table) and on (2) whether or not a 1-week erythropoiesis-stimulating agent-free interval was used. Peginesatide doses were titrated to maintain hemoglobin levels within [PLUS-MINUS SIGN]1.0 g/dL from baseline. RESULTS: A total of 164 patients were enrolled and received intravenous peginesatide every 4 weeks for up to 6 doses; the duration of the study including follow-up was [LESS-THAN OR EQUAL TO]29 weeks. Overall, the proportion of patients with hemoglobin levels within [PLUS-MINUS SIGN]1.0 g/dL of baseline increased over the course of the study from 39% (Weeks 2--13) to 54% (Weeks 18--25). Cohorts that used tiered dose conversion tables trended towards having more stable peginesatide doses than did those cohorts that used a single dose conversion ratio. Moreover, cohorts that used an erythropoiesis-stimulating agent-free interval did not have the substantial initial increase in hemoglobin levels that was seen in those cohorts that did not use such an interval. In this study, the safety profile of peginesatide was consistent with those of marketed erythropoiesis-stimulating agents. CONCLUSIONS: The results of this study were used to guide the dosing regimens used subsequently in phase 3 studies. Once-monthly peginesatide is feasible in hemodialysis patients.Trial registrationClinicalTrials.gov registration: NCT00228449.  相似文献   
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