RESUMEN
Up to 70 million U.S. adults have chronic sleep and wakefulness disorders. Therapies may include prescription medications approved by the Food and Drug Administration, off-label treatments, over-the-counter drugs, and herbal therapies.
RESUMEN
Although evidence has mounted in recent years for the biosynthetic relevance of [4 + 2] cycloaddition reactions, other cycloadditions have received much less attention. Herein we used density functional theory (DFT) calculations to assess the viability of nitrone-alkene (3 + 2) cycloaddition reactions proposed to occur during the biosynthesis of several alkaloid natural products (flueggines and virosaines). The results of our calculations indicate that these reactions have low enough intrinsic barriers and diastereoselectivity that they can proceed without enzymatic intervention.
Asunto(s)
Alcaloides/biosíntesis , Alcaloides/química , Alquenos/química , Productos Biológicos/síntesis química , Óxidos de Nitrógeno/química , Productos Biológicos/química , Reacción de Cicloadición , Estructura Molecular , Teoría Cuántica , EstereoisomerismoRESUMEN
This article provides a summary of clinical assessment methods and nonpharmacologic rehabilitation techniques used for concussed patients. It describes concussion-relevant physical examination methods to identify underlying symptom generators. This approach allows practitioners to prescribe targeted rehabilitation therapies to treat postconcussion symptoms. Evidence-based rehabilitation approaches include cervical rehabilitation, vestibulo-ocular rehabilitation, and sub-symptom threshold aerobic exercise.
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Traumatismos en Atletas/terapia , Conmoción Encefálica/terapia , Terapia por Ejercicio , Traumatismos en Atletas/diagnóstico , Traumatismos en Atletas/fisiopatología , Conmoción Encefálica/diagnóstico , Conmoción Encefálica/fisiopatología , Terapia por Ejercicio/métodos , Tolerancia al Ejercicio , Humanos , Grupo de Atención al Paciente , Examen Físico , Síndrome Posconmocional/terapiaRESUMEN
We examined priming of orthographically illegal nonwords in a perceptual identification task and a word judgment task in undergraduate participants. In perceptual identification, priming was significant and equivalent after structural or phonological encoding. In word judgment, priming was significant after phonological encoding but not structural encoding. In a follow-up experiment in older control participants and amnesic participants, priming in word judgment was not significant. Older control participants found the stimuli more difficult to pronounce than did undergraduate participants, and word judgment priming in undergaduate participants was significant only for the stimuli that were judged easy to pronounce. These findings demonstrate that priming in perceptual identification and word judgment extends to novel stimuli that are not linked to preexisting lexical or sublexical representations but that priming occurs at different levels in the two tasks: at a featural or orthographic level in perceptual identification and at a phonological level in word judgment.
Asunto(s)
Juicio , Percepción , Vocabulario , Anciano , Amnesia/diagnóstico , Femenino , Humanos , Masculino , Memoria , Reconocimiento en Psicología , Escalas de WechslerRESUMEN
The theoretical investigation of concerted and stepwise Cope rearrangements of natural products led to the prediction that some concerted Cope rearrangements can be promoted by noncovalent association of their transition state structures with ammonium cations.