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《Clinical neurophysiology》2021,132(5):1089-1104
ObjectiveDescribe and evaluate the concepts of near fiber electromyography (NFEMG), the features used, including near fiber motor unit potential (NFMUP) duration and dispersion, which relate to motor unit distal axonal branch and muscle fiber conduction time dispersion, and NFMUP segment jitter, a new measure of the temporal variability of neuromuscular junction transmission (NMJ), and axonal branch and muscle fibre conduction for the near fibres (i.e. NF jitter), and the methods for obtaining their values.MethodsTrains of high-pass filtered motor unit potentials (MUPs) (i.e. NFMUP trains) were extracted from needle-detected EMG signals to assess changes in motor unit (MU) morphology and electrophysiology caused by neuromuscular disorders or ageing. Evaluations using simulated needle-detected EMG data were completed and example human data are presented.ResultsNFEMG feature values can be used to detect axonal sprouting, conduction slowing and NMJ transmission delay as well as changes in MU fiber diameter variability, and NF jitter. These changes can be detected prior to alterations of MU size or numbers.ConclusionsThe evaluations clearly demonstrate and the example data support that NFMUP duration and dispersion reflect MU distal axonal branching, conduction slowing and NMJ transmission delay and/or MU fiber diameter variability and that NFMUP jiggle and segment jitter reflect NF jitter.SignificanceNFEMG can detect early changes in MU morphology and/or electrophysiology and has the potential to augment clinical diagnosis and tracking of neuromuscular disorders.  相似文献   
103.
ABSTRACT

Background: Addiction has been reported as a major personal, social and political challenge in people of different strata and education levels in all countries. The present study was conducted to predict addiction potential based on sensation-seeking, psychological hardiness and assertiveness in students.

Methods: The present correlational study was conducted in 2018 on a statistical population comprising all the students of the School of Medicine in Kermanshah University of Medical Sciences, Kermanshah, Iran. Convenience sampling was used to select 200 subjects. The data collection tools included the sensation-seeking scale, the psychological hardiness questionnaire, the assertion inventory and the addiction potential scale. The data collected were analyzed in SPSS using the statistical methods of the Pearson correlation coefficient and regression analysis.

Results: Analyzing the findings showed the total scores of addiction potential and active addiction potential are positively associated with the total score of sensation-seeking and negatively and significantly correlated with that of psychological hardiness.

Conclusions: Given the role of sensation-seeking, psychological hardiness and assertiveness in addiction potential, university authorities are recommended to hold workshops and seminars to enhance the awareness of students of the personality traits conducive to addiction.  相似文献   
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《Clinical neurophysiology》2021,132(4):1000-1007
ObjectiveTo investigate early pre-treatment nerve fiber loss as a predictor of long-term clinical outcome in chronic inflammatory demyelinating polyneuropathy (CIDP).MethodsIn 14 patients, motor and sensory conduction studies of the median, fibular, and sural nerves were performed at pre-treatment and follow-up 11–28 years later. Z-scores of amplitudes were combined as biomarkers of axonal loss and Z-scores of conduction properties as demyelination scores. The axonal loss was further examined by electromyography (EMG) and motor unit number estimation. Axonal and demyelination scores were compared to clinical outcomes in the Inflammatory Rasch-built Overall Disability Scale, the Neuropathy Impairment Score, and dynamometry.ResultsAt follow-up 12 patients walked independently, one needed support and one could not walk. The initial and follow-up axonal and demyelination scores were markedly abnormal. The initial axonal loss but not demyelination was strongly associated with both the follow-up axonal loss and the clinical measures. Moreover, delay of treatment initiation negatively influenced the axonal scores and clinical outcomes.ConclusionIn this hypothesis generating limited study, we found that axonal loss at early CIDP was highly predictive for long-term nerve fiber loss and disability.SignificanceThe study indicates that prompt initiation of treatment to prevent nerve fiber loss is necessary for outcome in CIDP.  相似文献   
106.
目的 研究131I治疗分化型甲状腺癌(DTC)患者体内放射性活度及外部剂量水平的变化规律,分析二者之间的关系,并估算400 MBq患者剂量当量率的修正因子。方法 研究对象为43例甲状腺全切术后,首次行131I"清甲"治疗的DTC患者,服药量为1 850~3 700 MBq,平均服药量(2 405±777)MBq。分别于口服131I后2、6、20、22、24、27、30、44、46、48、54、68及72 h,测定患者的体内剩余放射性活度以及患者前部0.3、1及3 m处的剂量当量率。结果 患者服131I后的体内剩余放射性活度随时间变化函数为A=A0(1.033 16e-0.062 4t+0.017 17)。可估算出"清甲"治疗的DTC患者有效半减期为12.19 h,体内放射性活度降至400 MBq仅需26.4~38.9 h。患者服用131I后距其0.3、1及3 m的标准化剂量当量率随时间变化函数分别为:0.3=127.220 7e-0.054 8t+3.765 71、1=30.225 8e-0.064 4t+0.824 67、3=4.161 9e-0.061 5t+0.167 97。患者服131I后体内剩余放射性活度与1 m处剂量当量率呈正相关(r=0.982,P<0.05),函数为1=0.025A+1.245。DTC患者体内剩余活度分别为1 000、700和400 MBq时,距患者1 m处对应的剂量当量率分为26.2、18.7和11.2 μSv/h。估算活度为400 MBq的患者0.3、1及3 m处剂量当量率的修正因子分别为0.25、0.49及0.70。结论 服用131I活度在3 700 MBq以下的DTC患者仅需住院2日便可达到出院标准。当DTC患者体内活度降至400 MBq时,其1 m处的剂量当量率远小于25 μSv/h。单纯利用点源公式估算患者周围剂量当量率会造成高估的情况,因此对于公式估算患者周围辐射水平时使用的修正因子还需进一步研究,使模型估算结果更贴合实际情况。  相似文献   
107.
《Clinical neurophysiology》2021,132(11):2789-2797
ObjectiveThis study aims to discriminate the dynamic synchronization states from the subthalamic local field potentials and investigate their correlations with the motor symptoms in Parkinson’s Disease (PD).MethodsThe resting-state local field potentials of 10 patients with PD were recorded from the subthalamic nucleus. The dynamic neural states of multiple oscillations were discriminated and analyzed. The Spearman correlation was used to investigate the correlations between occurrence rate or duration of dynamic neural states and the severity of motor symptoms.ResultsThe proportion of long low-beta and theta synchronized state was significantly correlated with the general motor symptom and tremor, respectively. The duration of combined low/high-beta state was significantly correlated with rigidity, and the duration of combined alpha/high-beta state was significantly correlated with bradykinesia.ConclusionsThis study provides evidence that motor symptoms are associated with the neural states coded with multiple oscillations in PD.SignificanceThis study may advance the understanding of the neurophysiological mechanisms of the motor symptoms and provide potential biomarkers for closed-loop deep brain stimulation in PD.  相似文献   
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109.
目的探讨可见光连续环境消毒系统(CED)对手术室真菌和细菌气溶胶浓度的影响以及与环境因素的相关性。方法以焦作市第二人民医院5间手术室作为研究对象,分别对CED应用前后手术室内生物气溶胶浓度进行检测,并进行真菌和细菌培养,将检测结果进行比较,并与同期检测的消毒前后的室内温度和湿度相关性进行分析。结果消毒前和消毒后强化消毒模式下手术室内细菌、真菌浓度均较常规消毒模式降低,其次术后消毒完成后强化消毒模式下室内相对湿度相比常规消毒降低,差异均有统计学意义(P<0.05)。消毒过程中手术室的相对湿度标准值为(41.12±4.06)%,温度为(23.41±2.07)℃。经Spearman相关分析显示,消毒后真菌和细菌浓度与相对湿度标准值呈正相关(r=0.109,0.107;P=0.034,0.037),与温度无相关性(P>0.05)。结论常规消毒措施上加用可见光连续环境消毒系统能大大降低手术室的菌群生物气溶胶浓度,同时维持室内相对湿度减少细菌和真菌的繁殖。  相似文献   
110.
ObjectivesThoracic surgery can cause significant pain, and multiple strategies have been developed to control pain after surgery. We compared 2 bupivacaine formulations given intraoperatively: bupivacaine with epinephrine (1,200,000) or liposomal bupivacaine.MethodsThis was a randomized, open-label study (NCT03560362). Eligible patients were adults scheduled for a minimally invasive lung procedure. Incision sites were injected with bupivacaine with epinephrine or liposomal bupivacaine before incision, and each intercostal space was injected with 1 mL of bupivacaine with epinephrine or liposomal bupivacaine entering the thoracic cavity. Patient-controlled analgesia was initiated in the recovery room. Pain was recorded using a visual analog scale. The primary outcome was the amount of narcotics taken during the postoperative hospital stay.ResultsWe recruited 50 patients; 25 received bupivacaine with epinephrine, and 25 received liposomal bupivacaine. The treatment groups were similar in age, histology, and procedure performed. There were no statistical differences between the treatment groups in the amount of narcotics required during the hospital stay (36.3 mg for bupivacaine and 38 mg for liposomal bupivacaine) or in pain assessed the day of surgery (5 and 5), the first day (3.5 and 2.3), second day (3 and 2.6), 2 weeks (0 and 1), or 3 months (0 and 0) postoperatively. Hospital length of stay and complications were also similar.ConclusionsIn a small, randomized study, we did not find significant differences between bupivacaine with epinephrine or liposomal bupivacaine in mitigating pain after minimally invasive lung resection. We currently favor using the less expensive nonliposomal bupivacaine preparations until additional data are available.  相似文献   
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