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31.
GeroScience - Adults aged 60 and over are most vulnerable to mild traumatic brain injury (mTBI). Nevertheless, the extent to which chronological age (CA) at injury affects TBI-related brain aging...  相似文献   
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The control of analytical quality of self-monitoring of blood glucose (SMBG) is recommended as a routine procedure in diabetes management. This control procedure should be easily accessible to patients, convenient, not time-consuming, and provide a reliable assessment of glucose meter performance. Optimally it should be located in the diabetes outpatient clinic. Presently there are two approaches to carrying out SMBG quality control. The first is based on the comparison of results obtained by a controlled glucose meter and use of the laboratory method or point-of-care testing device as a surrogate reference analyzer. The second one is a traditionally organized external quality assessment scheme with use of a dedicated control material, which is distributed to all participants. The recommended allowable meter error in SMBG can be realistically set at 10%.  相似文献   
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The conversion of [1,2-3H]corticosterone to 18-hydroxycorticosterone in vitro was studied on human and animal adrenal tissue homogenates. Human adrenals were surgically resected from a patient with Cushing's disease. Sheep adrenal homogenates were prepared from the pooled glands of 20 animals. Incubations supplemented with a NADPH generating system were performed in order to evaluate the effect of aminoglutethimide and its closely related compound glutethimide on corticosterone 18-hydroxylation in vitro. Increasing concentrations of the two drugs were assayed on both human and animal adrenal homogenates. Aminoglutethimide was clearly found to inhibit corticosterone 18-hydroxylation in sheep adrenal homogenates as a 72.6% inhibition occurred in the presence of only 0.2 mumole of the drug. Inhibition reached 91.1% in the presence of 0.5 mumole aminoglutethimide. When added to the human incubated adrenal, a 59.4% inhibition occurred in the presence of 0.5 mumole aminoglutethimide. Glutethimide, a sedative of wide clinical usage, was also found to inhibit corticosterone 18-hydroxylation but the inhibitory effect occurred only in the presence of much higher concentrations. In fact, 5.0 mumoles were necessary to obtain a 43.9% inhibition of 18-hydroxycorticosterone synthesis. This study clearly demonstrates the marked inhibitory effect of aminoglutethimide on corticosterone 18-hydroxylation. Glutethimide, to a lesser extent, also inhibits 18-hydroxycorticosterone synthesis.  相似文献   
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Constitutional thinness: unusual human phenotype of low bone quality   总被引:1,自引:0,他引:1  
CONTEXT: Low fat mass and hormonal or nutritional deficiencies are often incriminated in bone loss related to thinness. Constitutional thinness has been described in young women with low body mass index (BMI) but close-to-normal body composition, physiological menstruation, no hormonal abnormalities, and no anorexia nervosa (AN) psychological profile. OBJECTIVE: Our objective was to determine whether constitutional thinness is associated with impaired bone quality. DESIGN, SETTING, AND PARTICIPANTS: This was an observational, cross-sectional study on 25 constitutionally thin and 44 AN young women with similar low BMI (<16.5 kg/m2) and 28 age-matched controls. MAIN OUTCOME MEASURES: Femoral and lumbar spine bone mineral density by dual-energy x-ray absorptiometry, distal tibia and radius bone architecture and breaking strength by three-dimensional peripheral quantitative computed tomography, and bone turnover markers were determined. RESULTS: Constitutionally thin subjects displayed a higher percentage of fat mass than AN subjects but had similar lumbar and femoral bone mineral density, which were significantly lower than in controls (P < 0.001). Constitutionally thin subjects displayed more markedly impaired trabecular and cortical bone parameters in the distal tibia than in the radius. AN bone structure was impaired only in subjects with a long history of disease. Calculated breaking strength was decreased in constitutional thinness and long-standing AN in both the radius and the tibia. Bone markers in constitutionally thin subjects were similar to those of controls. Osteoprotegerin to receptor activator of nuclear factor kappa B ligand ratio was higher in constitutionally thin subjects than in controls or AN women. CONCLUSIONS: Young women with constitutional thinness present an unexpectedly high prevalence of low bone mass (44%) associated with small bone size, overall diminished breaking strength, but normal bone turnover. Mechanisms related to insufficient skeletal load and/or genetics are proposed to explain this new phenotype of impaired bone quality.  相似文献   
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Churg–Strauss syndrome (CSS) is a rare systemic small-vessel vasculitis that develops in the background of bronchial asthma, which is characterized by eosinophilia and eosinophilic infiltration of various tissues. It belongs to the group of antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitides. The triggering factors and pathogenesis of CSS are still unknown. The possible role of eotaxin-3 and CCR4-related chemokines in selective recruitment of eosinophils to the target tissues in CSS has been recently suggested, but the role of eosinophilic inflammation in the development of vasculitic lesions is not completely understood. From the clinical view, two distinct phenotypes of the disease are slowly emerging depending on the ANCA-positivity status. Glucocorticoids are still the mainstay of treatment; however, data are accumulating regarding the beneficial role of novel immunosuppressants and biologic compounds, especially in patients with poorer prognosis.  相似文献   
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