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目的了解不同机种军事飞行员运动心肺功能有无差异。方法飞行员分为高性能战斗机和普通战斗机两组,采用意大利COSMED运动心肺功能测试仪,选择自行车功率计运动方式,以25 W/min功率递增速率极量运动方案,进行运动心肺功能测试,比较两组运动心肺功能数据的主要指标。结果两组飞行员各207例完成运动心肺功能测试,两组的年龄、身高、体质量和体质量指数差异均无统计学意义(P均>0.05)。两组数据的主要指标中,除了峰值氧脉搏[高性能战斗机组(15.36±2.43)mL/bpm,普通战斗机组(14.95±2.13)mL/bpm]差异有统计学意义(P=0.038),其他差异均无统计学意义,而且各指标差异幅度均较小,高性能战斗机飞行员组的峰值氧脉搏高于普通战斗机组2.74%。结论综合比较,高性能战斗机和普通战斗机飞行员的运动心肺功能无明显差异,提示两组飞行员日常有氧运动训练效果一致,在转换飞行机种时,可以不受运动心肺功能的限制。  相似文献   
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【摘要】目的 探讨二维斑点追踪显像技术(2D-STI)评估新生儿窒息合并心肌损害后左心室整体及局部心肌的纵向收缩功能在早期诊断窒息新生儿心肌损害中的临床价值。方法 选择2019年07月至2020年12月期间在右江民族医学院附属医院新生儿科住院的足月窒息新生儿61例,经临床确诊合并心肌损害,根据Apgar评分分为轻度组31例和重度组30例,选择同期住院出生的正常足月新生儿30例作为对照组。检测受检者的血清肌酸激酶同工酶(CK-MB)、肌钙蛋白(cTnT)、左室舒张期前后径(LVDId)、左室射血分数(LVEF)、左室短轴缩短率(LVFS)、辛普森法左室射血分数(Simpson EF)、左室三腔心整体应变(GLS-LAX)、左室四腔心整体应变(GLS-A4C)、左室两腔心整体应变(GLS-A2C)、左室整体应变(GLS-AVG),分析GLS-AVG和CK-MB、cTnT三者的相关性。结果 三组间CK-MB和cTnT比较差异有统计学意义(P<0.05)。三组间性别、体重、胎龄均无统计学差异(P>0.05)。三组间LVDId、LVEF、LVFS、Simpson EF比较差异无统计学意义(P>0.05)。GLS-AVG与CK-MB呈负性相关(r=-0.515,P=0.000),GLS-AVG与cTnT呈负性相关(r=-0.912,P=0.000)。结论 GLS-AVG与CK-MB、cTnT具有相关性,GLS-AVG可作为窒息新生儿心肌损害早期诊断指标。  相似文献   
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ADHD儿童认知障碍的主要特征之一是执行功能损害,涉及包括前额叶皮层在内的特定脑区域及多层级脑网络异常。执行功能按照功能性分为冷-热两方面:冷执行功能损害主要表现于反应抑制、工作记忆以及认知灵活性等;热执行功能损害通常涉及延迟满足、赏罚相关决策、自我调节及情绪调节等。ADHD儿童的执行功能评估应基于可信范式进行文化适应性调整。临床干预不能单一聚焦于冷执行功能,需关注儿童的身体发育以及热执行功能(情绪社会方面)的发展进程,结合其他共病与心理状况,进行全面的动态随访与干预,以达到最佳的长期疗效。  相似文献   
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The main aim of the paper is to discuss current knowledge on how Age Related Macular Degeneration (AMD) affects Dark Adaptation (DA). The paper is divided into three parts. Firstly, we outline some of the molecular mechanisms that control DA. Secondly, we review the psychophysical issues and the corresponding analytical techniques. Finally, we characterise the link between slowed DA and the morphological abnormalities in early AMD.Historically, DA has been regarded as too cumbersome for widespread clinical application. Yet the technique is extremely useful; it is widely accepted that the psychophysically obtained slope of the second rod-mediated phase of the dark adaptation function is an accurate assay of photoreceptor pigment regeneration kinetics. Technological developments have prompted new ways of generating the DA curve, but analytical problems remain. A simple potential solution to these, based on the application of a novel fast mathematical algorithm, is presented. This allows the calculation of the parameters of the DA curve in real time.Improving current management of AMD will depend on identifying a satisfactory endpoint for evaluating future therapeutic strategies. This must be implemented before the onset of severe disease. Morphological changes progress too slowly to act as a satisfactory endpoint for new therapies whereas functional changes, such as those seen in DA, may have more potential in this regard. It is important to recognise, however, that the functional changes are not confined to rods and that building a mathematical model of the DA curve enables the separation of rod and cone dysfunction and allows more versatility in terms of the range of disease severity that can be monitored. Examples are presented that show how analysing the DA curve into its constituent components can improve our understanding of the morphological changes in early AMD.  相似文献   
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BackgroundCryotherapy is a frequently used therapy in the acute treatment of sports injuries, although it has possible negative effects on dynamic postural stabilization.Research questionWhat is the effect of cryotherapy on the postural stabilization assessed by imposed platform perturbations?MethodsTwenty-four healthy participants (15 male, 9 female) performed 2 test sessions (before and after cryotherapy) consisting of 4 trials each. Each trial included 30 s single leg stance (SLS) on both legs and 4 testing blocks (2 for each leg) of 30 s for the dynamic testing. A single testing block comprised 4 perturbations. After the first session, cryotherapy was applied to the right leg by placing it in ice water at a temperature between 10 °C and 12 ° for 20 min.Outcome measuresWe assessed the Center of Pressure speed (CoPs) and the mean force variation for both static and dynamic tests. Additionally, the Time To Stability (TTS) was calculated for the perturbations.ResultsIn the static trials there was an interaction between leg and session present for the mean force variation (p = 0.01) with a large η2 of 0.24, which shows higher variation of vertical force after application of the cryotherapy on the right leg. During the dynamic trials we found an interaction between leg and session for the TTS suggesting increase of the TTS due to the cryotherapy (p = 0.04), with a large η2 of 0.17. No interaction effect was present for the CoPs in the mediolateral and anteroposterior direction (p = 0.62 and p = 0.12, respectively).SignificanceCryotherapy applied to the lower extremity results in a worse postural stabilization when assessed by platform perturbations. This might be the result of an altered balance strategy, due to impaired proprioception from the affected body part. More research is needed to examine the duration of this effect.Level of evidenceLevel 3, associative study  相似文献   
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目的 研究社区获得性肺炎(community acquired pneumonia,CAP)患儿血清维生素A(vitamin A,VA)水平及与免疫功能的相关性,为肺炎病情评估提供一定参考。方法 以入住新乡医学院第一附属医院PICU的63例重度社区获得性肺炎(severe community acquired pneumonia, SCAP)患儿(SCAP组)、普通儿科病区的30例轻度社区获得性肺炎(mild community acquired pneumonia, MCAP)患儿(MCAP组),以及同期体检的30名健康儿童(对照组)为研究对象,检测其血清中VA和免疫球蛋白(immunoglobulin,Ig)G、IgA、IgM水平,及SCAP组体内T淋巴细胞亚群(总T淋巴细胞、CD4、CD8、CD4/CD8),并对SCAP组体内VA水平及以上指标的相关性进行分析。结果 3组性别和年龄差异无统计学意义;血清中VA的平均含量分别为0.36、0.25和0.19 mg/L,CAP组VA的含量较对照组明显降低,且SCAP组明显低于MCAP组( P<0.05)。根据WHO推荐的VA诊断标准,3组VA临床缺乏/亚临床缺乏率分别为10.00%、36.67%和61.90%,差异有统计学意义( P<0.05)。CAP组血清中Ig水平较对照组明显降低,且SCAP组明显低于MCAP组( P<0.05)。SCAP组血中总T淋巴细胞、CD4、CD8和CD4/CD8的平均水平分别为53.28%、30.26%、20.24%和1.59;分析VA水平与免疫相关指标关系发现VA水平与Ig(IgG、IgA、IgM)水平、总T淋巴细胞、CD4呈正相关,与CD8水平不相关。结论 肺炎患儿血清VA水平与病情严重程度及机体免疫功能相关。  相似文献   
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BackgroundFalls in older persons are associated with muscle mass and strength alterations, which may also affect balance parameters. However, the most appropriate combined approach to assess muscle and balance components that predict falls in older persons is still lacking.Research questionWe hypothesized that appendicular lean and/or mid-thigh mass and muscle strength and performance are positively associated with balance indices and fall risk in older persons.MethodsCross-sectional analyses of retrospective data from 260 participants with risk and/or history of falls examined at a Falls and Fracture Clinic. Assessments included a comprehensive clinical exam, bone densitometry and body composition by DXA, grip strength, gait speed, posturography, timed up and go (TUG) and four-square step (FSST) tests. Retrospective falls and fracture history was collected. Associations between appendicular and mid-thigh lean mass and muscle strength/performance vs balance indicators were determined before and after adjusting for age and gender.ResultsMean age of participants was 78 ± 6.7 (65−96) years. Both appendicular and mid-thigh lean masses corrected for BMI (but not for height2), and muscle strength and performance measures are associated with better dynamic balance. Conversely, static balance indicators showed less consistent associations with lean mass. Only TUG and sit to stand time consistently showed significant associations with most static balance indicators.SignificanceCombined with strength and performance parameters, ALM and mid-thigh estimates adjusted by BMI strongly correlate with dynamic balance parameters and could become practical elements of falls risk assessment as well as markers of therapeutic response to falls prevention interventions.  相似文献   
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BackgroundTextured insoles have been suggested to enhance foot sensation, which contributes to controlling upright balance. However, the interaction between plantar callosity and the textured surface has not been studied.Research questionFirstly, to compare the efficacy of textured insoles on balance performance and foot position sense between two groups of older people: one group had plantar callosity, and the other did not. Secondly, to investigate the efficacy of textured insoles within each study group.MethodsThirty older people with a history of falls (15 with plantar callosity and 15 without callosity) participated in this study. All participants underwent assessments of postural sway on a force plate, joint position sensation of the ankle with a slope box, and mobility using the "Timed Up and Go" test under three insole surface conditions: 1) smooth (control), 2) placebo and 3) textured surface. Two-way analyses of variance were used to compare the outcomes of the two groups and three conditions.ResultsOlder people with plantar callosity had worse ankle joint position sense and slower antero-posterior and mediolateral postural sway velocity than their peers who did not have plantar callosity. The textured insoles improved ankle joint position sense and mobility regardless of callus status in the plantar surface of older peoples’ feet. The insole-callosity interaction was not significant for any study outcome.SignificanceTextured insoles could be beneficial to older people with and without callosity as they have shown immediate improvements in ankle joint position sense and mobility.  相似文献   
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