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Numerous whole-body vibration (WBV) devices of various forces are available on the market, although their influence on the musculoskeletal system is not yet understood. The effect of different WBVs on bone healing and muscle function was evaluated in rats ovariectomized at 3 months of age. 2 months after ovariectomy, bilateral metaphyseal tibia osteotomy and T-plate osteosynthesis were performed. Rats were divided into groups: intact, OVX, and OVX exposed to vertical WBVs of 35, 50, 70, or 90 Hz (experiment 1) or horizontal WBVs of 30, 50, 70, or 90 Hz (experiment 2) 5 days after osteotomy (0.5 mm, 15 min/day for 30 days). The tibia and gastrocnemius and soleus muscles were collected. Vertical vibrations (>35 Hz) improved cortical and callus densities, enlarged callus area and width, suppressed the tartrate-resistant acid phosphatase gene, enhanced citrate synthase activity, accelerated osteotomy bridging (35 and 50 Hz), upregulated the osteocalcin (Oc) gene (70 Hz), and increased relative muscle weight (50 Hz). Horizontal vibrations reduced cortical width (<90 Hz) and callus density (30 Hz), enhanced alkaline phosphatase (Alp) gene expression (50 Hz), decreased the size of oxidative fibers (35 and 70 Hz), and increased capillary density (70, 90 Hz). Biomechanical data; serum Oc, Alp, and creatine kinase activities; body weight; and food intake did not change after WBVs. Vertical WBVs of 35 and 50 Hz produced more favorable results than the higher frequencies. Horizontal WBV showed no positive or negative effects. Further studies are needed to elucidate the effects of WBV on different physiological systems, and precautions must be taken when implementing WBV in the treatment of patients.  相似文献   
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Developmental Language Impairment (DLI) is a neurodevelopmental disorder affecting 12% to 14% of the school-age children in the United States. While substantial studies have shown a wide range of linguistic and non-linguistic difficulty in individuals with DLI, very little is known about the neuroanatomical mechanisms underlying this disorder. In the current study, we examined the subcortical components of the corticostriatal system in young adults with DLI, including the caudate nucleus, the putamen, the nucleus accumbens, the globus pallidus, and the thalamus. Additionally, the four cerebral lobes and the hippocampus were also comprised for an exploratory analysis. We used conventional magnetic resonance imaging (MRI) to measure regional brain volumes, as well as diffusion tensor imaging (DTI) to assess water diffusion anisotropy as quantified by fractional anisotropy (FA). Two groups of participants, one with DLI (n=12) and the other without (n=12), were recruited from a prior behavioral study, and all were matched on age, gender, and handedness. Volumetric analyses revealed region-specific abnormalities in individuals with DLI, showing pathological enlargement bilaterally in the putamen and the nucleus accumbens, and unilaterally in the right globus pallidus after the intracranial volumes were controlled. Regarding the DTI findings, the DLI group showed decreased FA values in the globus pallidus and the thalamus but these significant differences disappeared after controlling for the whole-brain FA value, indicating that microstructural abnormality is diffuse and affects other regions of the brain. Taken together, these results suggest region-specific corticostriatal abnormalities in DLI at the macrostructural level, but corticostriatal abnormalities at the microstructural level may be a part of a diffuse pattern of brain development. Future work is suggested to investigate the relationship between corticostriatal connectivity and individual differences in language development.  相似文献   
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Journal of Autism and Developmental Disorders - We evaluated the effectiveness of a statewide Medicaid program providing in-home Early Intensive Behavioral Intervention services to young children...  相似文献   
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We have generated three monoclonal cell‐penetrating antibodies (CPAbs) from a non‐immunized lupus‐prone (NZB × NZW)F1 mouse that exhibited high anti‐DNA serum titres. These CPAbs are polyreactive because they bind to DNA and other cellular components, and localize mainly in the nucleus of HeLa cells, albeit with a distinct nuclear labelling profile. Herein, we have examined whether DNA–histone complexes (DHC) binding to CPAbs, before cell entry, could modify the cell penetration of CPAbs or their nuclear staining properties. By applying confocal microscopy and image analysis, we found that extracellular binding of purified CPAbs to DHC significantly enhanced their subsequent cell‐entry, both in terms of percentages of positively labelled cells and fluorescence intensity (internalized CPAb amount), whereas there was a variable effect on their nuclear staining profile. Internalization of CPAbs, either alone or bound to DHC, remained unaltered after the addition of endocytosis‐specific inhibitors at 37° or assay performance at 4°, suggesting the involvement of energy‐independent mechanisms in the internalization process. These findings assign to CPAbs a more complex pathogenetic role in systemic lupus erythematosus where both CPAbs and nuclear components are abundant.  相似文献   
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