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Bone strength is predominantly determined by bone density, but bone microarchitecture also plays an important role. We examined whether trabecular bone score (TBS) predicts the risk of vertebral fractures in a Japanese female cohort. Of 1950 randomly selected women aged 15 to 79 years, we analyzed data from 665 women aged 50 years and older, who completed the baseline study and at least one follow‐up survey over 10 years, and who had no conditions affecting bone metabolism. Each survey included spinal imaging by dual‐energy X‐ray absorptiometry (DXA) for vertebral fracture assessment and spine areal bone mineral density (aBMD) measurement. TBS was obtained from spine DXA scans archived in the baseline study. Incident vertebral fracture was determined when vertebral height was reduced by 20% or more and satisfied McCloskey‐Kanis criteria or Genant's grade 2 fracture at follow‐up. Among eligible women (mean age 64.1 ± 8.1 years), 92 suffered incident vertebral fractures (16.7/103 person‐years). These women were older with lower aBMD and TBS values relative to those without fractures. The unadjusted odds ratio of vertebral fractures for one standard deviation decrease in TBS was 1.98 (95% confidence interval [CI] 1.56, 2.51) and remained significant (1.64, 95% CI 1.25, 2.15) after adjusting for aBMD. The area under the receiver operating characteristic curve of TBS and aBMD combined was 0.700 for vertebral fracture prediction and was not significantly greater than that of aBMD alone (0.673). However, reclassification improvement measures indicated that TBS and aBMD combined significantly improved risk prediction accuracy compared with aBMD alone. Further inclusion of age and prevalent vertebral deformity in the model improved vertebral fracture prediction, and TBS remained significant in the model. Thus, lower TBS was associated with higher risk of vertebral fracture over 10 years independently of aBMD and clinical risk factors including prevalent vertebral deformity. TBS could effectively improve fracture risk assessment in clinical settings. © 2014 American Society for Bone and Mineral Research.  相似文献   
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Monolayers of cardiac cells from 11-day-old chicken hearts have different properties when maintained in fetal calf serum or in a lipoprotein-deficient serum (LPDS). Cells in fetal calf serum have a resting potential near -60 mV; the rate of rise of the action potential is low (less than 10 V/sec); the action potential and the contraction are essentially unaffected by tetrodotoxin (TTX); and the beating properties are unaffected by muscarinic agents. Cells in LPDS have a resting potential near -75 mV, and a fast rise of the action potential (approximately equal to 100 V/sec) that is drastically decreased by TTX with a parallel abolition of contraction, and the beat is blocked by very low concentrations of muscarinic agonists. Cells that are physiologically fully responsive to TTX and to muscarinic agents have receptors that remain stable 24 hr after protein synthesis is blocked, whereas cells that are physiologically unresponsive to TTX and muscarinic agents have receptors that are rapidly degraded with half-lives between 9 hr (TTX receptor) and 14 hr (muscarinic receptor). Differences in the physiological and biochemical properties are accompanied by changes in the cholesterol contents of the cell membranes. The properties of cardiac cells cultured in normal serum are similar to those found for cells of chicken hearts in the very early embryonic stage, whereas those of cardiac cells cultured in LPDS correspond to the late embryonic stage.  相似文献   
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Münchausen syndrome is a disorder defined by the following: acute factitious symptoms leading to inappropriate investigation and therapy, a restless journey from hospital to hospital and autobiographical falsification. We report here a 20-year-old woman who presented at our hospital consultation of internal medicine with laboratory-test results suggesting the diagnosis of leukemia. A new complete blood cells count and a medullogram by sternal puncture did not show any abnormality. Comparative examination of laboratory-test sheets lead to the diagnosis of Münchausen syndrome as some results had been falsified. With unlimited access to information through internet and word or image processing softwares, laboratory results have become easy to falsify nowadays, particularly for patients with Münchausen syndrome, who may then be quite difficult to diagnose accurately in the context of medical consultation.  相似文献   
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Pediatric diffuse midline gliomas are devastating diseases. Among them, diffuse midline gliomas H3K27M‐mutant are associated with worse prognosis. However, recent studies have highlighted significant differences in clinical behavior and biological alterations within this specific subgroup. In this context, simple markers are needed to refine the prognosis of diffuse midline gliomas H3K27M‐mutant and guide the clinical management of patients. The aims of this study were (i) to describe the molecular, immunohistochemical and, especially, chromosomal features of a cohort of diffuse midline gliomas and (ii) to focus on H3K27M‐mutant tumors to identify new prognostic markers. Patients were retrospectively selected from 2001 to 2017. Tumor samples were analyzed by immunohistochemistry (including H3K27me3, EGFR, c‐MET and p53), next‐generation sequencing and comparative genomic hybridization array. Forty‐nine patients were included in the study. The median age at diagnosis was 9 years, and the median overall survival (OS) was 9.4 months. H3F3A or HIST1H3B mutations were identified in 80% of the samples. Within the H3K27M‐mutant tumors, PDGFRA amplification, loss of 17p and a complex chromosomal profile were significantly associated with worse survival. Three prognostic markers were identified in diffuse midline gliomas H3K27M‐mutant: PDGFRA amplification, loss of 17p and a complex chromosomal profile. These markers are easy to detect in daily practice and should be considered to refine the prognosis of this entity.  相似文献   
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