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101.
Objective Many tasks in natural language processing utilize lexical pattern-matching techniques, including information extraction (IE), negation identification, and syntactic parsing. However, it is generally difficult to derive patterns that achieve acceptable levels of recall while also remaining highly precise.Materials and Methods We present a multiple sequence alignment (MSA)-based technique that automatically generates patterns, thereby leveraging language usage to determine the context of words that influence a given target. MSAs capture the commonalities among word sequences and are able to reveal areas of linguistic stability and variation. In this way, MSAs provide a systemic approach to generating lexical patterns that are generalizable, which will both increase recall levels and maintain high levels of precision.Results The MSA-generated patterns exhibited consistent F1-, F.5-, and F2- scores compared to two baseline techniques for IE across four different tasks. Both baseline techniques performed well for some tasks and less well for others, but MSA was found to consistently perform at a high level for all four tasks.Discussion The performance of MSA on the four extraction tasks indicates the method’s versatility. The results show that the MSA-based patterns are able to handle the extraction of individual data elements as well as relations between two concepts without the need for large amounts of manual intervention.Conclusion We presented an MSA-based framework for generating lexical patterns that showed consistently high levels of both performance and recall over four different extraction tasks when compared to baseline methods. 相似文献
102.
103.
动脉导管未闭(PDA)是早产儿常见疾病,目前早产儿PDA的自然发展过程仍未完全明确,PDA发生的有些高危因素仍存在争议,对PDA是否进行药物、手术干预,以及何时进行药物、手术干预仍存在争议。尽管已经有相当多的证据证实动脉导管持续开放可能有害,但目前尚缺乏关闭导管治疗方案的远期益处或害处的相关证据。大多数临床试验旨在评估短期导管开放对患儿的影响。目前尚无评估动脉导管持续开放对早产儿死亡率及并发症影响的临床试验。近年来PDA治疗上最大的变化是减少对PDA的治疗。该文重点总结胎龄28周早产儿PDA的治疗策略。 相似文献
104.
《Vaccine》2016,34(32):3663-3669
ObjectiveTo evaluate the potential impact and value of applications (e.g. adjusting ordering levels, storage capacity, transportation capacity, distribution frequency) of data from demand forecasting systems implemented in a lower-income country's vaccine supply chain with different levels of population change to urban areas.Materials and MethodsUsing our software, HERMES, we generated a detailed discrete event simulation model of Niger's entire vaccine supply chain, including every refrigerator, freezer, transport, personnel, vaccine, cost, and location. We represented the introduction of a demand forecasting system to adjust vaccine ordering that could be implemented with increasing delivery frequencies and/or additions of cold chain equipment (storage and/or transportation) across the supply chain during varying degrees of population movement.ResultsImplementing demand forecasting system with increased storage and transport frequency increased the number of successfully administered vaccine doses and lowered the logistics cost per dose up to 34%. Implementing demand forecasting system without storage/transport increases actually decreased vaccine availability in certain circumstances.DiscussionThe potential maximum gains of a demand forecasting system may only be realized if the system is implemented to both augment the supply chain cold storage and transportation. Implementation may have some impact but, in certain circumstances, may hurt delivery. Therefore, implementation of demand forecasting systems with additional storage and transport may be the better approach. Significant decreases in the logistics cost per dose with more administered vaccines support investment in these forecasting systems.ConclusionDemand forecasting systems have the potential to greatly improve vaccine demand fulfilment, and decrease logistics cost/dose when implemented with storage and transportation increases. Simulation modeling can demonstrate the potential health and economic benefits of supply chain improvements. 相似文献
105.
Luís A. Bastião Silva Luís S. Ribeiro Milton Santos Nuno Neves Dulce Francisco Carlos Costa José Luis Oliveira 《Journal of digital imaging》2015,28(6):671-683
The production of medical imaging is a continuing trend in healthcare institutions. Quality assurance for planned radiation exposure situations (e.g. X-ray, computer tomography) requires examination-specific set-ups according to several parameters, such as patient’s age and weight, body region and clinical indication. These data are normally stored in several formats and with different nomenclatures, which hinder the continuous and automatic monitoring of these indicators and the comparison between several institutions and equipment. This article proposes a framework that aggregates, normalizes and provides different views over collected indicators. The developed tool can be used to improve the quality of radiologic procedures and also for benchmarking and auditing purposes. Finally, a case study and several experimental results related to radiation exposure and productivity are presented and discussed. 相似文献
106.
Joseane Balan Da Silva Gleison Daion Piovezana Bossolani Camila Piva Greicy Brisa Malaquias Dias Jancarlo Gomes Ferreira Diogo Francisco Rossoni 《International journal of environmental health research》2016,26(5-6):578-588
The spatial distribution of enteroparasitosis in an indigenous village from Paraná was evaluated to identify areas of risk for these infections. A cross-sectional study (from November 2010 to June 2011) was performed using Three Faecal Test® and Kato &; Katz method and a questionnaire on housing and hygiene conditions was administered. Local geostatistical analyses were performed to determine the spatial distribution of intestinal parasitic infections. The overall prevalence of enteroparasites was 67.2?% (457/680), and the most prevalent taxa were Ascaris lumbricoides (48.8?%) and Trichuris trichiura (44.7?%). The prevalence of heavy infection by soil-transmitted helminths was 3.6?% and the families lived in houses with an average of 5.1 residents and < 2 bedrooms per household. The average number of species per individual present spatial heterogeneity with the highest values (≥0.8) in areas with high clustering of residences. The visualization of the spatial distribution of intestinal parasites in this indigenous village is an important contribution to determining health risk areas and planning decisions and services. 相似文献
107.
Objective and subjective measures of the neighbourhood environment: Associations with frailty levels
ObjectivesThe aim of this study was to investigate whether perceptions of the neighbourhood environment (NE) and objective measures of the NE were associated with frailty in older adults.MethodsA cross-sectional study in Adelaide, Australia, recruited a sample of 115 community-dwelling adults aged ≥60 years. Respondents’ perceptions of their NEs were assessed using the Neighbourhood Environment Walkability Scale (NEWS). An objective assessment of these NEWS survey questions was conducted using seven variables: residential density, land use mix diversity, street connectivity, accessibility, seasonal persistent green cover, road crash density and crime rate. Frailty was evaluated using the FRAIL (fatigue, resistance, ambulation, illnesses and loss of weight) scale. Multivariable linear regression analyses were employed to assess the associations between NEWS and frailty, and to assess the associations between objective neighbourhood variables and frailty.ResultsFrail and pre-frail older adults were more likely to live in areas with lower residential density, lower density of road crashes, and higher accessibility than robust participants. Additionally, a poorer perception of the overall environment, worse land-use mix and accessibility and worse crime safety were associated with frailty and pre-frailty after adjustment of covariates and objective GIS variables.DiscussionNeighbourhood characteristics, both objective and perceived, are associated with frailty levels in older adults, and that strategies to tackle frailty must consider the impact of the neighbourhood environment. 相似文献
108.
以厦门市作为国家药品集中采购试点城市的政策要求为背景,分析了原有区域人口健康信息平台在支持试点工作中存在的不足之处.结合厦门市基于大数据架构的全民健康信息平台的建设,开展了全市药品信息实时监测的实践,包括全市药品使用概况、试点药品的采购及使用情况、多维度分析及跨部门数据共享,为促进政府多部门的联合监管、决策提供重要的数据支持. 相似文献
109.
《Health policy (Amsterdam, Netherlands)》2020,124(5):519-524
Cross-border healthcare has become a major policy issue in the past years across the European Union. Professional mobility, as a means of providing specialised health services has not been given sufficient attention in both the research and policy agendas. This paper presents a case study of the contribution made by visiting overseas medical specialists to the health system in Malta. Twenty-five semi-structured interviews were conducted. A grounded theory approach was utilised in view of the limited amount of literature available on the subject. Qualitative content analysis revealed one superordinate theme, being the value of the service, and three further subthemes, which include the quality of the service provided, its longevity and durability, as well as the critical contributions of expatriates. The service is an integral component of the local health service. This study makes an important contribution to the literature on cross-border healthcare. Lessons learnt may be transferable to other small island states and territories. The European Reference Networks being developed at EU level may need to focus more on the benefits that can accrue through short term professional mobility than has been the case to date. The findings also serve to propose several important features that need to be in place to increase the chances of longevity, sustainability, quality and cost effectiveness in cross border health care services. 相似文献
110.