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ObjectivesTo study the prevalence of benign EEG variants (BEVs) in the sleep–wake cycle among 1163 consecutive patients.MethodsProspective, observational EEG study using the 10–20 system with systematically two additional anterior-temporal electrodes. Depending on clinical indications, other electrodes were added. REM sleep identification was based on its characteristic EEG grapho-elements and rapid eye movements, clearly detectable with the additional anterior-temporal and fronto-polar electrodes due to eye proximity. The video-EEG monitoring duration was between 24 hours and eight days.ResultsWe identified 710 patients (61%) with BEVs. Positive occipital sharp transients of sleep (POSTs) were observed in 36.4% of participants, mu rhythm in 22.4%, lambda waves in 16.7%, wicket spikes (WS) in 15%, 14- and 6-Hz positive bursts in 8.3%, benign sporadic sleep spikes (BSSS) in 3.3%, rhythmic mid-temporal theta burst of drowsiness (RMTD) in 2.15%, midline theta rhythm in 2.1% and six-Hz spike and wave (SW) bursts in 0.1%. WS and RMTD were present during wakefulness, NREM (14.1%, 1.3%, respectively) and REM sleep (3.3%, 1.1%, respectively). Mu rhythm was also observed during NREM (1.5%) and REM sleep (7.7%). Fourteen- and 6-Hz positive bursts were present during NREM (4.5%) and REM sleep (6.5%). BSSS and six-Hz SW bursts were only observed during NREM sleep.ConclusionsThe prevalence of BEVs is much higher than current estimates. POSTs and WS can no longer be considered as unusual patterns but physiological patterns of NREM sleep. RMTD and mu rhythm may be observed during NREM and REM sleep.  相似文献   
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Mild cognitive impairment associated with Parkinson's disease (PD) is a risk factor for the development of dementia. Despite the importance of early identification of mild cognitive impairment in PD, its prevalence and clinical correlates are still debated. The present meta-analysis provides a robust estimate of prevalence rate of mild cognitive impairment in PD according to the Movement Disorder Society clinical criteria and to explore the differences between PD patients with and without mild cognitive impairment in demographic, clinical, and neuropsychiatric features. A systematic literature search was performed up to April 2019 using PsycInfo (PROQUEST), PubMed, and Scopus. From 4706 titles and abstracts, 41 studies were selected (n = 7053 patients). Pooled mild cognitive impairment prevalence was 40% on a total sample of 7053 PD patients (95% confidence interval = 36–44; Q = 490.14, P < 0.0001; I2 = 91.84%) with a higher frequency for the multiple domain subtype (31%; 95% confidence interval = 23–41, Q = 93.24; P < 0.0001; I2 = 92.49%). Meta-regression analysis revealed that stage of PD moderate prevalence estimates of mild cognitive impairment (β = 2.80; P = 0.008). Mild cognitive impairment in PD was associated with older age, lower education, longer disease duration, higher levodopa equivalent daily dose, more severe motor symptoms, and postural instability/gait difficulty motor subtype, poorer quality of life, higher levels of apathy, and depression. The present meta-analysis indicated that mild cognitive impairment in PD is a frequent cognitive status deserving to be early detected by means of standardized cognitive assessments in clinical practice. © 2019 International Parkinson and Movement Disorder Society  相似文献   
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Journal of Neurology -  相似文献   
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Journal of Neurology - Italy is one of the most affected countries by the coronavirus disease 2019 (COVID-19). The responsible pathogen is named severe acute respiratory syndrome coronavirus...  相似文献   
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