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1.
World Hosp Health Serv ; 45(1): 4-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19670517

RESUMO

Policy analysis can contribute to meeting health objectives by untangling the complex forces of power and process that underpin change. Health policy analysis has not been adequately developed and applied in low and middle income countries. Building a critical mass of networked researchers and policy-makers provides the key to developing the field and improving its contribution to health outcomes.


Assuntos
Formulação de Políticas , Qualidade da Assistência à Saúde , Humanos , Resultado do Tratamento
2.
J Nucl Med ; 50(9): 1409-17, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19690021

RESUMO

UNLABELLED: The magnitude of the injected activity (A(0)) has a direct impact on the statistical quality of PET images. This study aimed to develop a generalized method for maximizing the statistical quality of dynamic PET images by optimizing A(0). METHODS: Patient-specific noise-equivalent counts (PS-NECs) were used as a metric of the statistical quality of each time frame of a dynamic PET image. Previous methodology developed to extrapolate the NEC as a function of A(0) was extended to dynamic PET, enabling the NEC to be extrapolated as a function of both A(0) and the time after injection. This method allowed A(0) to be optimized after a single scan (at a single A(0)), by maximizing the NEC within the time interval for which the parameter estimation is most sensitive. The extrapolation method was validated by a series of (15)O-H(2)O scans of the body acquired in 3-dimensional mode. Each patient (n = 6) underwent between 3 and 6 scans at 1 bed position. The injected activities were varied over a wide range (140-840 MBq). Noise-equivalent counting rate (NECR) versus A(0) curves and the optimal injected activities were calculated from each injection. RESULTS: PS-NECR versus A(0) curves as extrapolated from different injected activities were consistent (coefficient of variation, typically <5%). The optimal injected activities for an individual, as derived from these curves, were also consistent (maximum coefficient of variation, 4.3%). For abdominal (n = 4) and chest (n = 1) scans, we found optimal injected activities of (15)O-H(2)O in the range of 220-350 MBq for estimating blood perfusion (F) and 660-1,070 MBq for estimating the volume of distribution (V(T)). Higher optimal injected activities were found in the case of a pelvic scan (n = 1; 570 MBq for F and 1,530 MBq for V(T)). CONCLUSION: PS-NECs are a valid and generic method for optimizing the injected activity in PET, allowing scanning protocols to be improved after the collection of an initial, single dynamic dataset. This generic method can be used to estimate the optimal injected activity, which is specific to the patient, tracer, PET scanner, and body region being scanned.


Assuntos
Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Radioisótopos de Oxigênio/farmacocinética , Tomografia por Emissão de Pósitrons/métodos , Simulação por Computador , Humanos , Injeções Intravenosas , Taxa de Depuração Metabólica , Modelos Biológicos , Modelos Estatísticos , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Água/metabolismo
3.
Bull World Health Organ ; 87(11): 846-51, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20072770

RESUMO

This paper considers new developments to strengthen sexual and reproductive health and HIV linkages and discusses factors that continue to impede progress. It is based on a previous review undertaken for the United Kingdom Department for International Development in 2006 that examined the constraints and opportunities to scaling up these linkages. We argue that, despite growing evidence that linking sexual and reproductive health and HIV is feasible and beneficial, few countries have achieved significant scale-up of integrated service provision. A lack of common understanding of terminology and clear technical operational guidance, and separate policy, institutional and financing processes continue to represent significant constraints. We draw on experience with tuberculosis and HIV integration to highlight some lessons. The paper concludes that there is little evidence to determine whether funding for health systems is strengthening linkages and we make several recommendations to maximize opportunities represented by recent developments.


Assuntos
Saúde Global , Infecções por HIV/prevenção & controle , Infecções por HIV/terapia , Serviços de Saúde Reprodutiva/organização & administração , Integração de Sistemas , Organização do Financiamento , Infecções por HIV/diagnóstico , Humanos , Cooperação Internacional
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