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A 25-year-old, emaciated man without medical treatment was found to have died suddenly at home by his mother. At autopsy, there were no injuries to his body, but significant circulatory insufficiency was observed. Electron microscopy revealed abnormal mitochondria in cells of the cardiac conduction system. The conduction system was filled with mitochondrial size abnormalities and mitochondrial cristae abnormalities. No notable abnormal findings were observed in other organs. Genetic examination of the blood revealed the mitochondrial pathogenetic variant m.3243A>G. Epileptic seizures, diabetic ketoacidosis, and hyperosmolar hyperglycemic state were unlikely to be the cause of sudden death. The cause of death was diagnosed as arrhythmia possibly induced by the failure of the cardiac conduction system due to mitochondrial disease. This is a rare case of sudden death caused by an accumulation of abnormal mitochondria in the cardiac conduction system.  相似文献   
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《Clinical neurophysiology》2021,132(9):2003-2011
ObjectiveA large N20 and P25 of the median nerve somatosensory evoked potential (SEP) predicts short survival in amyotrophic lateral sclerosis (ALS). We investigated whether high frequency oscillations (HFOs) over N20 are enlarged and associated with survival in ALS.MethodsA total of 145 patients with ALS and 57 healthy subjects were studied. We recorded the median nerve SEP and measured the onset-to-peak amplitude of N20 (N20o-p), and peak-to-peak amplitude between N20 and P25 (N20p-P25p). We obtained early and late HFO potentials by filtering SEP between 500 and 1 kHz, and measured the peak-to-peak amplitude. We followed up patients until endpoints (death or tracheostomy) and analyzed the relationship between SEP or HFO amplitudes and survival using a Cox analysis.ResultsPatients showed larger N20o-p, N20p-P25p, and early and late HFO amplitudes than the control values. N20p-P25p was associated with survival periods (p = 0.0004), while early and late HFO amplitudes showed no significant association with survival (p = 0.4307, and p = 0.6858, respectively).ConclusionsThe HFO amplitude in ALS is increased, but does not predict survival.SignificanceThe enlarged HFOs in ALS might be a compensatory phenomenon to the hyperexcitability of the sensory cortex pyramidal neurons.  相似文献   
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IntroductionThere is still no consensus in the literature as to the best acoustic stimulus for capturing vestibular evoked myogenic potential (VEMP). Low-frequency tone bursts are generally more effective than high-frequency, but recent studies still use clicks. Reproducibility is an important analytical parameter to observe the reliability of responses.ObjectiveTo determine the reproducibility of p13 and n23 latency and amplitude of the VEMP for stimuli with different tone-burst frequencies, and to define the best test frequency.MethodsCross-sectional cohort study. VEMP was captured in 156 ears, on the sternocleidomastoid muscle, using 100 tone-burst stimuli at frequencies of 250, 500, 1000, and 2000 Hz, and sound intensity of 95 dB nHL. Responses were replicated, that is, recorded three times on each side.ResultsNo significant difference was observed for p13 and n23 latencies of the VEMP, captured at three moments with tone-burst stimuli at 250, 500, and 1000 Hz. Only the frequency of 2000 Hz showed a difference between captures of this potential (p < 0.001). p13 and n23 amplitude analysis was also similar in the test–retest for all frequencies analyzed.Conclusionp13 and n23 latencies and amplitudes of VEMP for tone-burst stimuli at frequencies of 250, 500, and 1000 Hz are reproducible.  相似文献   
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目的 探讨快速康复外科 (FTS)理念在经后颅窝乙状窦后入路三叉神经微血管减压术围术期患者护理中的应用效果。方法 选择2018年1月~2019年1月我院收治并行经后颅窝乙状窦后入路三叉神经微血管减压患者100例,随机分成观察组和对照组,每组50例。对照组应用常规方法进行围术期护理,观察组应用FTS理念进行围术期护理。比较两组焦虑情况、术后并发症发生率、平均住院日及平均住院费用。结果 观察组轻度焦虑多于对照组,中、重度焦虑少于对照组(P<0.05);观察组术后并发症发生率低于对照组[恶心呕吐(4.00% vs 16.00%)、尿路感染(4.00% vs 18.00%)、颅内感染(0 vs 8.00%)、颅内血肿(2.00% vs 14.00%)和术后应激性疼痛(16.00% vs 34.00%)],差异有统计学意义(P<0.05);观察组平均住院日和平均住院费用均低于对照组[(9.13±1.14)d vs(12.44±0.89)d];[(2.15±0.66)万元 vs (3.05±0.61)万元],差异有统计学意义(P<0.05)。结论 应用FTS理念能缓解经后颅窝乙状窦后入路三叉神经微血管减压术患者术前紧张恐惧的心理,减少术后并发症,缩短患者住院日,降低住院费用,护理效果较好。  相似文献   
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BackgroundGait impairments following anterior cruciate ligament reconstruction (ACLR) may contribute to reinjury or future osteoarthritis development. Recently, plantar cutaneous sensation deficits have been reported post-ACLR. These sensory deficits may influence gait and represent a mechanism through which to improve gait.Research questionCan established sensory interventions change sensation and gait in patients after ACLR and compared to healthy adults?MethodsTwenty-two adults (n = 11 post-ACLR, age:20.5 ± 1.9years, body mass index[BMI]:24.5 ± 3.6 kg/m2; n = 11 healthy, age:20.7 ± 1.4years, BMI:23.3 ± 2.7 kg/m2) completed two sessions separated by 48 h. Gait and plantar cutaneous sensation were assessed pre- and post-intervention (massage or textured insoles). Gait analysis was completed using 3D motion capture at 1.4 m/s ± 5% and standard inverse dynamics analysis. Plantar cutaneous sensation was assessed using Semmes Weinstein Monofilaments with a 4−2-1 stepping algorithm at the plantar aspect of the first metatarsal head, base of the fifth metatarsal, and lateral and medial malleoli. Plantar massage was a 5-minute massage to both feet. Textured insoles (coarse grit sandpaper) were worn while walking. Biomechanical data were assessed via mixed-models, repeated measures ANOVAs and 90 % confidence intervals. Wilcoxon Signed Rank tests and Mann-Whitney U tests evaluated plantar cutaneous sensation within and between groups, respectively.ResultsKnee adduction moment was lower in the ACLR versus the contralateral limb pre-massage. The vGRF was lower during the first half of stance but greater during the second half of stance in the ACLR versus the control group post-massage. Massage improved ACLR limb sensation over the first metatarsal head (P = 0.042) and medial malleolus (P = 0.027). Textured insole application improved ACLR limb sensation over the first (P = 0.043) and fifth (P = 0.027) metatarsals and medial malleolus (P = 0.028).SignificancePlantar massage and textured insoles improved plantar cutaneous sensation in the ACLR limb. Neither intervention influenced gait. Improving plantar sensation may be beneficial for patients after ACLR; however, sensory interventions to improve gait are necessary.  相似文献   
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