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ObjectiveWe investigated changes in attention mechanisms in people who report a high number of somatic symptoms which cannot be associated with a physical cause.MethodBased on scores on the Somatoform Disorder Questionnaire (SDQ-20; Nijenhuis et al., 1996) we compared two non-clinical groups, one with high symptoms on the SDQ-20 and a control group with low or no symptoms. We recorded EEG whilst participants performed an exogenous tactile attention task where they had to discriminate between tactile targets following a tactile cue to the same or opposite hand.ResultsThe neural marker of attentional orienting to the body, the Late Somatosensory Negativity (LSN), was diminished in the high symptoms group and attentional modulation of touch processing was prolonged at mid and enhanced at later latency stages in this group.ConclusionThese results confirm that attentional processes are altered in people with somatic symptoms, even in a non-clinical group. Furthermore, the observed pattern fits explanations of changes in prior beliefs or expectations leading to diminished amplitudes of the marker of attentional orienting to the body (i.e. the LSN) and enhanced attentional gain of touch processing.SignificanceThis study shows that high somatic symptoms are associated with neurocognitive attention changes.  相似文献   
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BackgroundSensory disorders frequently accompany the motor disorders in children with cerebral palsy (CP).Research questionDo children with CP have sensory disturbances in their lower extremities? If there are sensory impairments, do these impairments affect gait?MethodsIn total, 45 children (18 females, 27 males) in an age range between 5 and 18 years were included in the study: 15 typically developing children, 15 unilaterally affected children with cerebral palsy, and 15 bilaterally affected children with cerebral palsy. They could walk independently at the levels of I or II according to the gross motor function classification. After the demographic data of the children were recorded, their tactile sense, vibration sense, two-point discrimination, and proprioception were evaluated, and the Edinburgh Visual Gait Score (EVGS) was used for gait assessment.ResultsFailures were discovered in lower extremity tactile (p = 0.001), two-point discrimination (p = 0.001), and proprioceptive senses of the children with CP (p = 0.001), and the loss of tactile sense was found to be related to gait disorders (p = 0.02, r = 0.41).SignificanceThere were deficiencies in the lower extremity senses, and deficiencies in the tactile sense negatively affected gait. Performing sensory assessments, which are considered to be fundamental for gait training in the rehabilitation of children with CP, and providing support for the lacking parameters in the intervention programs may create positive effects on gait.  相似文献   
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目的通过心肺运动试验观察心脏外科术后患者早期的运动能力特点。方法纳入安贞医院行心脏外科术后行早期心肺运动试验的患者,接受心脏外科手术后3个月内行心肺运动试验的患者40例,以手术日至心肺运动试验检查日的天数将患者分为出院组(术后30 d内,20例)、术后1月组(术后30~60 d,10例)和术后2月组(术后60~90 d,10例),探讨不同时段心脏外科术后患者的运动能力特点;另将20例出院组按手术类型又分为大血管组(9例)、搭桥组(6例)和瓣膜组(5例),并进一步观察不同手术类型患者出院时(术后30 d内)的运动能力,即观察不同时段和不同手术类型的所有患者从静息开始运动到无氧阈强度时的心率变化、收缩压变化,以及心肺运动试验指标(无氧阈、峰值摄氧量及二氧化碳通气当量)。结果所有患者均完成无氧阈值以上的心肺运动试验,未发生运动意外等不良事件。①不同时段患者的运动能力:出院组达到无氧阈时的心率上升(8.8±7.1)次/min,显著低于术后1月组[(17.0±5.9)次/min]和术后2月组[(18.3±10.5)次/min],且差异有统计学意义(P<0.05);出院组的无氧阈和峰值摄氧量分别为(8.0±1.5)和(11.0±2.9)ml/(kg·min),显著低于术后1月组[(11.2±3.1)和(15.6±4.2)ml/(kg·min)]和术后2月组[(11.9±2.6)和(15.7±2.8)ml/(kg·min)],差异均有统计学意义(P<0.05),而术后1月组与术后2月组的无氧阈和峰值摄氧量组间比较,差异均无统计学意义(P>0.05);各组患者收缩压变化值及二氧化碳通气当量的组间差异均无统计学意义(P>0.05)。②术后30 d内不同手术类型患者的运动能力:大血管组和搭桥组术后患者的无氧阈[(7.2±1.3)和(7.8±0.7)ml/(kg·min)]及峰值摄氧量[(10.4±2.9)和(9.4±1.3)ml/(kg·min)],分别明显低于瓣膜组[(9.6±1.5)ml/(kg·min)及(14.2±2.3)ml/(kg·min)],且差异有统计学意义(P<0.05)。结论心脏外科术后患者的运动能力在术后30~60 d显著提高,而大血管术和搭桥术患者术后30 d内的运动能力明显低于瓣膜术后患者。  相似文献   
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目的 探讨神经阈值在糖尿病周围神经病变诊断中的应用价值。 方法 选取糖尿病患者42人纳入病变组,健康志愿者21人纳入健康对照组,其中,将病变组按照糖尿病病程长短分为两个亚组,病程<10年组(23人)、病程≥10年组(19人)。按照HbA1c水平将病变组分为两个亚组,HbA1c<9组(23人)和HbA1c≥9组(19人)。检测正中神经、尺神经及腓浅神经感觉支的神经阈值,并进行统计学分析。 结果 从健康对照组、病程<10年组至病程≥10年组,神经阈值逐渐增高,病变组神经阈值明显高于健康对照组(P<0.05),病程≥10年组又明显高于病程<10年组(P<0.05)。从健康对照组、HbA1c<9组至HbA1c≥9组,神经阈值逐渐增高,病变组神经阈值明显高于健康对照组(P<0.05),HbA1c≥9组又明显高于HbA1c<9组(P<0.05)。相关性分析提示,尺神经的运动神经阈值和腓浅神经感觉支的感觉神经阈值与HbA1c水平呈正相关(P<0.05),而正中神经的运动神经阈值与HbA1c水平之间无显著相关性(P>0.05)。3条神经的运动/感觉神经阈值与病程均呈正相关(P<0.05)。 结论 神经阈值随糖尿病病程及HbA1c水平变化而变化,反映了神经兴奋性的动态变化情况,有助于糖尿病神经病变的诊断及周围神经功能评估。  相似文献   
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Conclusions: In patients with total sudden sensorineural hearing loss (SSNHL), oral prednisone (OP) alone or intratympanic dexamethasone (ITD) alone have comparable results. The addition of salvage ITD following OP does not seem to add over either single modality treatment. Objectives: To study the effect of steroid-based treatments in patients with total SSNHL. Methods: The medical charts of 59 patients with total loss of hearing, defined as pure tone thresholds in the profound range (> 90 dB) with an unobtainable speech reception threshold (SRT) that were treated with OP (n = 20), ITD (n = 13), or OP followed by salvage ITD (n = 26) were analyzed. Response to treatment was evaluated by means of pure tone thresholds, SRT, and speech discrimination score (SDS), immediately after treatment and on a follow-up visit. Results: Forty-nine patients (83%) responded to treatment, with mean significant improvements of 36, 34, 31, and 25 dB at 500, 1000, 2000, and 4000 Hz, respectively. The mean improvement in SRT was 33 dB, and SDS improved by 32%. There were no differences in improvement in pure tone thresholds and SRT among the three treatment groups. The late effect of OP was similar to the effect of salvage ITD.  相似文献   
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Assessment of a chemical's potential to cause permanent changes in the genetic code has been a common practice in the industry and regulatory settings for decades. Furthermore, the genetic toxicity battery of tests has typically been employed during the earliest stages of the research and development programs of new product development. A positive outcome from such battery has a major impact on the chemical's utility, industrial hygiene, product stewardship practices, and product life cycle analysis, among many other decisions that need to be taken by the industry, even before the registration of a chemical is undertaken. Under the prevailing regulatory paradigm, the dichotomous (yes/no) evaluation of the chemical's genotoxic potential leads to a conservative, linear no-threshold (LNT) risk assessment, unless compelling and undeniable data to the contrary can be provided to satisfy regulators, typically in a number of different global jurisdictions. With the current advent of predictive methods, new testing paradigms, mode-of-action/adverse outcome pathways, and quantitative risk assessment approaches, various stakeholders are starting to employ these state-of-the-science methodologies to further the conversation on decision making and advance the regulatory paradigm beyond the dominant LNT status quo. This commentary describes these novel methodologies, relevant biological responses, and how these can affect internal and regulatory risk assessment approaches. Environ. Mol. Mutagen. 61:84–93, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
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