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1.
BackgroundOlder adults benefit most from engaging in higher-intensity physical activity, which is often determined using step rate thresholds. Fixed step rate thresholds that correspond to moderate (MPA) and vigorous-intensity physical activity (VPA) have been developed for heuristic activity promotion. The activPAL monitor uses step rate thresholds to determine activity intensity. Stepping thresholds may also vary based on body mass index (BMI) or aerobic fitness level in older adults. Despite the various thresholds used in the literature, it is unclear whether they produce similar outcomes.Research QuestionHow does time spent in physical activity intensities compare between different step rate thresholds in older adults?MethodsThirty-eight participants (24♀; 67 ± 4 years; BMI: 26.6 ± 4.4 kg/m2) wore an activPAL monitor 24-hr/day for up to 7-d (total: 205-d). Aerobic fitness (V̇O2max: 23 ± 8 ml/kg/min) was determined via indirect calorimetry during a maximal, graded cycling test. Time spent in each intensity category (light-physical-activity [LPA], MPA, VPA) was determined using the fixed (MPA/VPA) 100/130, 110/130, and activPAL step rate thresholds (74/212), as well as BMI-adjusted absolute (108.5 ± 2.5/134.0 ± 4.8) and BMI-adjusted relative (40%/60% V̇O2max; 111.4 ± 14.7/132.0 ± 19.0) cut-offs. Times spent in each intensity category were compared between methods.ResultsThe activPAL and 100/130 thresholds yielded less LPA and more MPA than all other methods. The activPAL had no time spent in VPA at all. The BMI-adjusted absolute and relative thresholds produced statistically equivalent time in LPA and MPA (via equivalence testing), but not VPA. No two methods yielded similar time spent in LPA, MPA, or VPA.SignificanceThe choice of step rate threshold has a major impact on physical activity intensity outcomes in older adults. Inherently, strategies that adjust for older adults’ body size and/or aerobic fitness level provide a more individualized data processing strategy than fixed thresholds that assume the same threshold for all older adults  相似文献   
2.
人工智能(Artificial Intelligence,AI)的蓬勃兴起为现代社会带来了前所未有的机遇,中医药是中华民族传承千年的文化瑰宝。随着人工智能技术不断在中医药领域的科技创新中崭露头角,二者的融合不断加深,人工智能在中医药领域的发展前景、争议挑战也引发了诸多思考。本文将从人工智能在中医药领域的应用入手,对人工智能辅助中医诊断、智能决策与数据挖掘、健康管理及中草药现代化研究等方面,就近年来国内外研究进展进行总结与分析,以期为AI视域下实现中医药现代化、智能化赋能。  相似文献   
3.
目的 探讨郑州地区孕妇铁营养状况及其影响因素。方法 以2021年4—8月在郑州市某三家医院建立健康档案并进行孕期体检的孕妇作为研究对象进行问卷调查及铁营养状况检测,采用描述流行病学方法对孕妇铁营养状态进行分析,并采用单、多因素分析方法对孕妇铁缺乏状况影响因素进行分析。结果 共有3 258例孕妇参与本次研究,其中妊娠早期989例,占30.36%,妊娠中期1 125例,占34.53%,妊娠晚期1 144例,占35.11%。在3 258名孕妇中,共有773例为铁缺乏,铁缺乏的检出率为23.73%。多因素分析结果显示,年龄≥35岁(OR=2.726)、处于妊娠的中期或晚期(OR=3.037,3.438)、月经初潮年龄<13岁(OR=2.432)、经产妇(OR=3.493)、流产次数≥3次(OR=2.648)、孕前月经量≥100 mL/次(OR=2.420)、文化程度为初中及以上(OR=0.517,0.459)、居住在农村(OR=3.684)、家庭月收入>3 000元及以上(OR=0.601,0.542)、居住房屋装修时间<1年(OR=6.449)、罹患消化系统疾病(OR=4.716)、有营养补齐剂摄入(OR=0.355)是孕妇铁缺乏的影响因素。结论 郑州市孕妇铁缺乏检出率较高,需要尽早给予针对性的干预。部分因素被确定为该地区孕妇人群发生铁元素缺乏的影响因素,可选择性的对其中危险因素给予干预。  相似文献   
4.
目的 基于临床信息系统分析总结真实世界的数据,采用数据挖掘的方法探讨中医药治疗糖尿病肾病的用药规律。方法 收集2018年1月-2020年12月上海中医药大学附属曙光医院宝山分院健康信息系统确诊的糖尿病肾病的门诊或住院患者的诊疗信息,建立Excel数据库,采用Excel 2010软件统计高频药物的四气、五味、归经及功效;使用SPSS Modeler 18.0软件中的Apriori算法分析关联规则,采用web节点建构药对关联网状图;运用SPSS 25统计软件进行因子分析。结果 本研究最终纳入477例接受中药饮片治疗的DKD患者,在1203条方剂信息中,涉及中药462种;使用频数排名前5位的中药分别是黄芪、黄精、石斛、山茱萸、麦冬;使用频数前5类的中药类别分别是补气药、补阴药、清热燥湿药、活血调经药、息风止痉药;在30味高频药物中,苦、甘、辛药味最为常见;药性寒、温数量接近;归脾经、肝经、肺经、肾经居多;关联规则提示,药物组合中置信度最高的组合为地龙-当归-僵蚕,因子分析共得到5个有效因子,累积贡献率为47.33%。结论 中医药治疗DKD在补益气血阴阳的同时,兼顾对瘀血、湿邪和痰饮的治疗,结合证型,可考虑使用黄芪、黄精、石斛、山茱萸、麦冬、金蝉花等药物的使用,清热燥湿药物如黄连、黄芩、黄柏可适当加入,为使邪有去处,大黄、车前子或可增添疗效。  相似文献   
5.
In this paper, we argue that understanding and addressing the problem of poor-quality medical products requires a more interdisciplinary approach than has been evident to date. While prospective studies based on rigorous standardized methodologies are the gold standard for measuring the prevalence of poor-quality medical products and understanding their distribution nationally and internationally, they should be complemented by social science research to unpack the complex set of social, economic, and governance factors that underlie these patterns. In the following sections, we discuss specific examples of prospective quality surveys and of social science studies, highlighting the value of cross-sector partnerships in driving high-quality, policy-relevant research in this area.  相似文献   
6.
《Vaccine》2016,34(51):6626-6633
BackgroundSafety signal detection in spontaneous reporting system databases and electronic healthcare records is key to detection of previously unknown adverse events following immunization. Various statistical methods for signal detection in these different datasources have been developed, however none are geared to the pediatric population and none specifically to vaccines. A reference set comprising pediatric vaccine-adverse event pairs is required for reliable performance testing of statistical methods within and across data sources.MethodsThe study was conducted within the context of the Global Research in Paediatrics (GRiP) project, as part of the seventh framework programme (FP7) of the European Commission. Criteria for the selection of vaccines considered in the reference set were routine and global use in the pediatric population. Adverse events were primarily selected based on importance. Outcome based systematic literature searches were performed for all identified vaccine-adverse event pairs and complemented by expert committee reports, evidence based decision support systems (e.g. Micromedex), and summaries of product characteristics. Classification into positive (PC) and negative control (NC) pairs was performed by two independent reviewers according to a pre-defined algorithm and discussed for consensus in case of disagreement.ResultsWe selected 13 vaccines and 14 adverse events to be included in the reference set. From a total of 182 vaccine-adverse event pairs, we classified 18 as PC, 113 as NC and 51 as unclassifiable. Most classifications (91) were based on literature review, 45 were based on expert committee reports, and for 46 vaccine-adverse event pairs, an underlying pathomechanism was not plausible classifying the association as NC.ConclusionA reference set of vaccine-adverse event pairs was developed. We propose its use for comparing signal detection methods and systems in the pediatric population.  相似文献   
7.
PurposeBibliometric studies have been established methods of analysing publications on a particular topic. These studies have been done on various orthopaedic topics and are increasing. The advantages of these studies have been highlighted in previous publications. Although some studies have been done on Indian publications from other specialties, those analysing Indian Orthopaedic Publications are lacking.MethodsWe performed a search in Scopus to look for all publications related to orthopaedics from India. Our search strategy in Scopus included ((TITLE-ABS-KEY(Orthopaedics OR Orthopaedics) AND AFFIL(India)) AND PUBYEAR > 2009 AND PUBYEAR < 2020) which resulted in 3270 articles on 02/11/2021. We analyzed the most publishing universities, city, state, specialty, authors, and anatomic location of these publications. We also mined the data to draw word clouds based on data obtained from the titles of articles, keywords and the affiliations of each of the articles published.ResultsTamil Nadu and New Delhi and their institutes appear to be the epicenter of publication activities in Orthopaedics in India. There has been a healthy trend of growth of articles in the orthopaedic specialty. Since there is a significant overlap of technology and engineering, it is not surprising to see engineering and technology institutes among the top 10 published institutes and even journals for the publications on orthopaedics.ConclusionThere has been a steady increase in the number of publications in the last decade. New Delhi and its Universities and Institutes appear to contribute the majority of citations and publications related to orthopaedics. Journal of Clinical Orthopaedics and Trauma was the most publishing journal for Indian authors on Orthopaedic related articles.  相似文献   
8.
《Brain stimulation》2020,13(1):175-189
BackgroundTranscranial magnetic stimulation (TMS) enables non-invasive modulation of brain activity with both clinical and research applications, but fundamental questions remain about the neural types and elements TMS activates and how stimulation parameters affect the neural response.ObjectiveTo develop a multi-scale computational model to quantify the effect of TMS parameters on the direct response of individual neurons.MethodsWe integrated morphologically-realistic neuronal models with TMS-induced electric fields computed in a finite element model of a human head to quantify the cortical response to TMS with several combinations of pulse waveforms and current directions.ResultsTMS activated with lowest intensity intracortical axonal terminations in the superficial gyral crown and lip regions. Layer 5 pyramidal cells had the lowest thresholds, but layer 2/3 pyramidal cells and inhibitory basket cells were also activated at most intensities. Direct activation of layers 1 and 6 was unlikely. Neural activation was largely driven by the field magnitude, rather than the field component normal to the cortical surface. Varying the induced current direction caused a waveform-dependent shift in the activation site and provided a potential mechanism for experimentally observed differences in thresholds and latencies of muscle responses.ConclusionsThis biophysically-based simulation provides a novel method to elucidate mechanisms and inform parameter selection of TMS and other cortical stimulation modalities. It also serves as a foundation for more detailed network models of the response to TMS, which may include endogenous activity, synaptic connectivity, inputs from intrinsic and extrinsic axonal projections, and corticofugal axons in white matter.  相似文献   
9.
文题释义:股骨头坏死中日友好医院分型的有限元分析:根据李子荣等提出的中日友好医院分型,建立股骨头坏死三维模型,分为 M型(内侧型)、C型(中央型)和 L型(外侧型),其中 L型包括L1型(次外侧型)、L2型(极外侧型)和 L3型(全头型)。通过对建立的模型进行有限元分析,为该分型的保髋治疗提供了一定力学依据,显示外侧柱的存留是精准预防塌陷的重要因素,为进一步实现个体化治疗提供力学基础。 腓骨支撑坏死股骨头保髋手术:是对于早中期股骨头坏死需要保留股骨头患者进行的一种手术方式。首先需对股骨头进行髓芯减压,清除一定坏死骨,空腔填塞松质骨(髂骨为主),打压结实后植入腓骨(异体或自体)支撑,给坏死区的提供力学支撑及生物学修复,预防股骨头进一步坏死及塌陷。 背景:研究报道股骨头坏死的保髋疗效与外侧柱存留密切相关,中日友好医院分型是根据三柱结构确立的,对股骨头塌陷的预测准确性高。 目的:建立股骨头坏死中日友好医院分型各分型仿真的三维有限元模型,通过有限元分析各分型腓骨植入的力学变化,探讨外侧柱存留对保髋疗效的意义,为该分型的塌陷精准预测提供基础。 方法:建立正常股骨头、中日友好医院分型(M型、C型、L1型、L2型、L3型)股骨头坏死及其腓骨植入3组11种三维有限元模型,运用ANSYS软件进行有限元分析计算,观察各组模型的最大应力值、最大位移值及股骨头内部载荷传递模式。 结果与结论:①坏死组位移最大,应变最大,且因坏死分型不同而位移不同,位移变化如下:M型相似文献   
10.
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