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Healthy Start is the UK government's food voucher programme for low‐income pregnant women and young children. It was introduced in 2006, but the impact of the programme on nutritional outcomes remains understudied. This study sought to explore potential outcomes of the Healthy Start programme (including intended and unintended outcomes) and develop explanations for how and why these outcomes might occur. A realist review preceded this study, in which programme theories were developed and tested using existing evidence. This qualitative study aimed to further refine and consolidate the programme theories from the realist review while remaining open to new and emerging theories (or hypotheses) about how low‐income pregnant women use Healthy Start vouchers. Semistructured interviews were conducted with 11 low‐income women from North West England, who received Healthy Start vouchers during pregnancy. A realist logic of analysis was applied to generate clear and transparent linkages between outcomes and explanations. The findings suggested that some women used the vouchers to improve their diets during pregnancy (intended outcome), whereas some women were diverted towards alternative or unintended outcomes. Women's circumstances, values, beliefs, and motivations influenced how they perceived and responded to the vouchers. This paper presents four evidence‐based programme theories to explain four contrasting (and potentially overlapping) outcomes: dietary improvements (theory refined from review), shared benefits (new theory), financial assistance (theory refined from review), and stockpiling formula (new theory). It considers how the Healthy Start programme could be improved, to increase the possibilities for low‐income women to experience the intended outcome of dietary improvements.  相似文献   
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Background: Studies of thunderstorm asthma to understand risk factors using high-resolution climate data and asthma outcomes on a large scale are scarce. Moreover, thunderstorm asthma is not well studied in the United States.Objectives: We examined whether climate parameters involved in thunderstorms are associated with emergency department (ED) visits for acute asthma attacks in the United States.Methods: We analyzed 63,789 asthma-related, daily ED visits for all age groups, and thunderstorm-associated climate data in Louisiana during 2010 through 2012. We performed time-series analyses using quasi-Poisson regression models with natural cubic splines of date, parish, holiday, day of week, season, daily maximum concentrations of ozone (O3) and fine particulate matter [PM 2.5μm in aerodynamic diameter (PM2.5)], and daily mean pressure, precipitation, and temperature. Because of a significant interaction effect between temperature and lightning days on asthma-related visits, we performed stratified analyses by days with/without lightning or thunderstorm (defined by any lightning and precipitation).Results: On thunderstorm days, higher asthma-related ED visits were associated with higher daily mean precipitation [relative risk (RR)=1.145 per 1g/m2/s (95% CI: 1.009, 1.300)] and lower daily mean temperature [RR=1.011 per 1°C change (1.000–1.021)] without carry-over effect to the next non-thunderstorm day. These higher risks were found mainly among children and adults <65 years of age. We observed similar results on lightning days. However, we did not find similar associations for non-thunderstorm or non-lightning days. Daily maximum O3 and PM2.5 levels were not significantly associated with asthma ED visits on thunderstorm days.Discussion: Higher precipitation and lower temperature on thunderstorm days appear to contribute to asthma attacks among people with asthma, suggesting they should consider taking precautions during thunderstorms. EDs should consider preparing for a potential increase of asthma-related visits and ensuring sufficient stock of emergency medication and supplies for forecasted severe thunderstorm days. https://doi.org/10.1289/EHP10440  相似文献   
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Two non-covalently linked copies of the retrovirus genome are specifically recruited to the site of virus particle assembly and packaged into released particles. Retroviral RNA packaging requires RNA export of the unspliced genomic RNA from the nucleus, translocation of the genome to virus assembly sites, and specific interaction with Gag, the main viral structural protein. While some aspects of the RNA packaging process are understood, many others remain poorly understood. In this review, we provide an update on recent advancements in understanding the mechanism of RNA packaging for retroviruses that cause disease in humans, i.e., HIV-1, HIV-2, and HTLV-1, as well as advances in the understanding of the details of genomic RNA nuclear export, genome translocation to virus assembly sites, and genomic RNA dimerization.  相似文献   
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Ultrasound is widely used as a screening tool for fetal anomalies. An intracardiac echogenic focus (ICEF) is associated with fetal aneuploidy, particularly trisomy 21, when found with other minor abnormalities known as soft markers. However, when found in isolation, intracardiac echogenic foci are morphologic variations with little or no pathologic significance for the fetus. Ambiguity about the significance of ICEF and other soft markers and the lack of preparation prior to ultrasound can result in unnecessary worry for women and their partners. A variety of tools exist that providers can use to help pregnant women and their partners make informed decisions about ultrasound and fetal screening.  相似文献   
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A 51-year-old woman presented with a large abdominopelvic mass suspicious on preoperative imaging for ovarian malignancy. At laparotomy, a large cystic mass was found originating from the uterus and adherent to the proximal ileum. Pathologic evaluation confirmed the diagnosis of cystic leiomyoma.  相似文献   
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