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ObjectivePericonceptional intake of folic acid reduces the risk of neural tube defects (NTDs), a frequent birth defect that can cause significant infant mortality and disability. In Chile, fortification of wheat flour with folic acid has resulted in significant reduction in the risk of anencephaly and spina bifida. We investigated the cost-effectiveness implications of this policy.MethodsWe conducted an ex-post economic analysis of this intervention. Estimates of the effect of fortification in decreasing NTDs and deaths were derived from a prospective evaluation. The costs of fortification and provision of medical care to children with spina bifida in Chile were based on primary data collection.FindingsThe intervention costs per NTD case and infant death averted were I$ 1200 and 11,000, respectively. The cost per DALY averted was I$ 89, 0.8% of Chile's GDP per capita. Taking into account averted costs of care, fortification resulted in net cost savings of I$ 2.3 million.ConclusionFortification of wheat flour with folic acid is a cost-effective intervention in Chile, a middle income country in the post-epidemiological transition. This result supports the continuation of the Chile fortification program and constitutes valuable information for policy makers in other countries to consider.  相似文献   
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Aim

To describe computed tomography (CT)-imaging findings in human metapneumovirus (HMPV)-related pulmonary infection as well as their temporal course and to analyze resemblances/differences to pulmonary infection induced by the closely related respiratory-syncytial-virus (RSV) in immunocompromised patients.

Materials and methods

Chest-CT-scans of 10 HMPV PCR-positive patients experiencing pulmonary symptoms were evaluated retrospectively with respect to imaging findings and their distribution and results were then compared with data acquired in 13 patients with RSV pulmonary infection. Subsequently, we analyzed the course of chest-findings in HMPV patients.

Results

In HMPV, 8/10 patients showed asymmetric pulmonary findings, whereas 13/13 patients with RSV-pneumonia presented more symmetrical bilateral pulmonary infiltrates. Image analysis yielded in HMPV patients following results: ground-glass-opacity (GGO) (n = 6), parenchymal airspace consolidations (n = 5), ill-defined nodular-like centrilobular opacities (n = 9), bronchial wall thickening (n = 8). In comparison, results in RSV patients were: GGO (n = 10), parenchymal airspace consolidations (n = 9), ill-defined nodular-like centrilobular opacities (n = 10), bronchial wall thickening (n = 4). In the course of the disease, signs of acute HMPV interstitial pneumonia regressed transforming temporarily in part into findings compatible with bronchitis/bronchiolitis.

Conclusions

Early chest-CT findings in patients with HMPV-related pulmonary symptoms are compatible with asymmetric acute interstitial pneumonia accompanied by signs of bronchitis; the former transforming with time into bronchitis and bronchiolitis before they resolve. On the contrary, RSV-induced pulmonary infection exhibits mainly symmetric acute interstitial pneumonia.  相似文献   
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The societal cost of preterm birth indicates potential economic gains from interventions that reduce the incidence of preterm birth. Changes in the epidemiology of preterm birth and healthcare costs require periodic updates to cost estimates. Previously reported incremental cost estimates for the United States in 2004 were updated. The discounted present value of the excess cost associated with prematurity for the 2016 US birth cohort was estimated to be $25.2 billion: $17.1 billion for medical care of persons born preterm, $2.0 billion for delivery care, $1.3 billion for early intervention and special education, and $4.8 billion in lost productivity due to associated disabilities in adults. The nominal and inflation-adjusted incremental costs per preterm birth increased by 26% and 4%, respectively, during 2004–2016. The aggregate cost decreased by 4%, associated with declines in overall births and the preterm birth rate and changes in the distribution by gestational age.  相似文献   
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The high incidence of inappropriate therapies due to supraventricular tachycardia remains a major unsolved problem of the implantable cardioverter defibrillator. A new morphology discrimination (MD) algorithm has been introduced to improve specificity of ICD therapy without loss of sensitivity. It was the aim of this study to systematically analyze sensitivity and specificity of the MD criterion in combination with the enhanced detection criteria sudden onset and rate stability in the detection of ventricular and supraventricular tachycardia. After ICD implantation in 259 patients, 787 detected episodes in 74 patients with available stored electrograms were documented during a follow-up period of 359 +/- 214 days. With a nominal programming of the MD algorithm at > or = 60%, sensitivity and specificity for all episodes were 82.6%/77.2%. For sinus tachycardia, atrial fibrillation and atrial flutter the specificities were 80.6%, 69.6% and 75%, respectively. In patients with primarily appropriate MD detection, sensitivity and specificity significantly improved to 95.8%/91.7%. Programming the sudden onset criterion with < 100 ms and the stability criterion with < 50 ms, sensitivity and stability of the combined application of the MD algorithm and sudden onset and MD algorithm and stability were 96.2%/52.2% and 94.4%/63.8%, respectively. The MD criterion in combination with other enhanced detection criteria might significantly improve specificity of tachyarrythmia detection of ICD therapy.  相似文献   
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Histological and scanning electron microscopy studies (SEM) suggest a classification of neural elements into five main types: receptor cells, bipolar cells, horizontal, amacrine, and ganglion cells in dissociated cell cultures of the retina from 7 to 10 days old chick embryos. By use of SEM the development of the receptor cell inner segments was observed. At the same time many protrusions were noticed at the receptor cell surface. Specific synaptic contacts between the axons of the receptor cells and the dendrites of the bipolar neurons, as well as unspecific contacts between the pericarya of the receptor cells and other dendrites were demonstrated. The bipolar neurons showed smooth cell surfaces, however, the horizontal cells appeared rough on the cell surfaces. Müller cells were always found adjacent to the photoreceptor cells.  相似文献   
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