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Abstract thinking is generally highly correlated with problem-solving ability which is predictive of better adaptive functioning. Measures of conceptual reasoning, an ecologically-valid laboratory measure of problem-solving, and a report measure of adaptive functioning in the natural environment, were administered to children and adults with and without autism. The individuals with autism had weaker conceptual reasoning ability than individuals with typical development of similar age and cognitive ability. For the autism group, their flexible thinking scores were significantly correlated with laboratory measures of strategy formation and rule shifting and with reported overall adaptive behavior but not socialization scores. Therefore, in autism, flexibility of thought is potentially more important for adaptive functioning in the natural environment than conceptual reasoning or problem-solving.  相似文献   
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Chronic stress and depression have adverse consequences on many organ systems, including the skeleton, but the mechanisms underlying stress‐induced bone loss remain unclear. Here we demonstrate that neuropeptide Y (NPY), centrally and peripherally, plays a critical role in protecting against stress‐induced bone loss. Mice lacking the anxiolytic factor NPY exhibit more anxious behavior and elevated corticosterone levels. Additionally, following a 6‐week restraint, or cold‐stress protocol, Npy‐null mice exhibit three‐fold greater bone loss compared to wild‐type mice, owing to suppression of osteoblast activity. This stress‐protective NPY pathway acts specifically through Y2 receptors. Centrally, Y2 receptors suppress corticotropin‐releasing factor expression and inhibit activation of noradrenergic neurons in the paraventricular nucleus. In the periphery, they act to control noradrenaline release from sympathetic neurons. Specific deletion of arcuate Y2 receptors recapitulates the Npy‐null stress response, coincident with elevated serum noradrenaline. Importantly, specific reintroduction of NPY solely in noradrenergic neurons of otherwise Npy‐null mice blocks the increase in circulating noradrenaline and the stress‐induced bone loss. Thus, NPY protects against excessive stress‐induced bone loss, through Y2 receptor‐mediated modulation of central and peripheral noradrenergic neurons. © 2014 American Society for Bone and Mineral Research.  相似文献   
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The soluble and ionized calcium and magnesium contents of 18 lots of Mueller-Hinton agar medium from three different manufacturers were analyzed, and the results were correlated with medium performance. A standardized disk diffusion test, with Pseudomonas aeruginosa (ATCC 27853) and a 10-microgram gentamicin disk, served as an indicator of medium performance. Zone diameters correlated well with the ionized calcium values and the sum of the ionized calcium and soluble magnesium values in the different lots (r = -0.88 for both). Zone diameters correlated poorly with ionized magnesium values (r = -0.57), which were best described by a curvilinear relationship. Supplementation of lots of Mueller-Hinton agar medium with equivalent amounts of calcium and magnesium as the chloride, gluconate, or glycerophosphate salts produced identical decreases in zone sizes. Adjustment of deficient lots of Mueller-Hinton agar medium with ionized calcium or soluble magnesium or both (as the gluconate salts), to match the concentrations in lots that provided satisfactory zone sizes (17 to 19 mm), resulted in performance comparable to that of the control lots. Sixteen strains of Pseudomonas aeruginosa, ranging from resistant to susceptible, responded to cation adjustment in the same manner as the ATCC quality control strain. Satisfactory medium performance can obviously be assured by biological means in aminoglycoside susceptibility testing of Pseudomonas aeruginosa on Mueller-Hinton medium; however, cation adjustment of medium to predetermined levels of ionized calcium and soluble magnesium can now also provide desirable performance levels for P. aeruginosa on Mueller-Hinton medium.  相似文献   
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We examined motor and tactile-perceptual skills in individuals with high-functioning autism (IHFA) and matched typically developing individuals (TDI) ages 5–21 years. Grip strength, motor speed and coordination were impaired in IHFA compared to matched TDI, and the differences between groups varied with age. Although tactile-perceptual skills of IHFA were impaired compared to TDI on several measures, impairments were significant only for stereognosis. Motor and tactile-perceptual skills should be assessed in children with IHFA and intervention should begin early because these skills are essential to school performance. Impairments in coordination and stereognosis suggest a broad though selective under-development of the circuitry for higher order abilities regardless of domain that is important in the search for the underlying disturbances in neurological development.  相似文献   
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People with autism spectrum disorder (ASD) often exhibit superior performance in visual search compared to others. However, most studies demonstrating this advantage have employed simple, uncluttered images with fully visible targets. We compare the performance of high-functioning adults with ASD and matched controls on a naturalistic luggage screening task. Although the two groups were equally accurate in detecting targets, the ASD adults improve in their correct elimination of target-absent bags faster than controls. This feature of their behavior is extremely important for many real-world monitoring tasks that require sustained attention for long time periods. Further analyses suggest that this improvement is attributable neither to the motor speed nor to the level of intelligence of the adults with ASD. These findings may have possible implications for employment opportunities of adult individuals with ASD.  相似文献   
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We describe the corneal microstructural changes in a patient with spheroidal degeneration using in vivo confocal microscopy. Multiple hypo‐ and hyper‐reflective spherical lesions were observed in the anterior corneal stroma and Bowman's layer ranging from 45 to 220 μm in size. The corneal epithelium, posterior stroma and endothelium were otherwise unaffected. In vivo confocal microscopy demonstrates good correlation with excised histological samples in climatic droplet keratopathy. It provides a non‐invasive technique to examine the living cornea for degenerative disease and acts as a bridge between clinical and laboratory observations.  相似文献   
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