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Introduction: We investigated the effect of age on the complexity of muscle activity and the variance in the force of isometric contraction. Methods: Surface electromyography (sEMG) from biceps brachii muscle and force of contraction were recorded from 96 subjects (20–70 years of age) during isometric contractions. Results: There was a reduction in the complexity of sEMG associated with aging. The relationship of age and complexity was approximated using a bilinear fit, with the average knee point at 45 years. There was an age‐associated increase in the coefficient of variation (CoV) of the force of muscle contraction, and this increase was correlated with the decrease in complexity of sEMG (r2 = 0.76). Conclusions: There was an age‐associated increase in CoV and also a reduction in the complexity of sEMG. The correlation between these 2 factors can be explained based on the age‐associated increase in motor unit density. Muscle Nerve 47: 545–549, 2013  相似文献   
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Abstract

Neuroimaging studies in schizophrenia help clarify the neural substrates underlying the pathogenesis of this neuropsychiatric disorder. Contemporary brain imaging in schizophrenia is predominated by magnetic resonance imaging (MRI)-based research approaches. This review focuses on the various imaging studies from India and their relevance to the understanding of brain abnormalities in schizophrenia. The existing studies are predominantly comprised of structural MRI reports involving region-of-interest and voxel-based morphometry approaches, magnetic resonance spectroscopy and single-photon emission computed tomography/positron emission tomography (SPECT/PET) studies. Most of these studies are significant in that they have evaluated antipsychotic-naïve schizophrenia patients – a relatively difficult population to obtain in contemporary research. Findings of these studies offer robust support to the existence of significant brain abnormalities at very early stages of the disorder. In addition, theoretically relevant relationships between these brain abnormalities and developmental aberrations suggest possible neurodevelopmental basis for these brain deficits.  相似文献   
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Migration is now well understood to be associated with mental illness in many parts of the world. However, the cause and effects of migration that are associated with mental illness continue to be a point of debate. The Ethnic Density concepts give a plausible explanation. On further elaboration, we conclude that a move from a sociocentric society to an egocentric one leads to more distress and more mental illness. Cultural incongruity faced by a migrant in an alien culture has a similar impact. Several theories on migratory distress have tried to explain psychiatric morbidity: high morbidity at source, individual predisposition, stress, misdiagnosis and racial discrimination. We hypothesise that the impact of ethnic density and cultural congruity occurs in a social context.  相似文献   
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Pharmaceutical Chemistry Journal - Eulophia nuda Lindl. (Orchidaceae) is a small perennial terrestrial herb found in central and Southeast Asian regions usually known for its ethnomedicinal uses by...  相似文献   
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