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91.
Sex hormones have important effects on bone, especially in postmenopausal women. These hormones may be of particular significance in patients with rheumatoid arthritis (RA), who have a high frequency of osteoporosis. To examine this, we measured estrogen and androgen concentrations and bone mineral density (BMD) in 49 postmenopausal women with RA and 49 normal postmenopausal women. Compared with the controls, postmenopausal RA patients had significantly reduced levels of estrone (median 18 pmoles/liter versus 49; P < 0.001), dehydroepiandosterone sulfate (DHEAS) (median 0.3 μmoles/liter versus 2.0; P < 0.001), testosterone (median 0.6 nmoles/liter versus 0.95; P < 0.001), and femoral BMD (mean 0.72 gm/cm2 versus 0.80; P < 0.002). Prednisolone therapy in 22 patients (mean dosage 8 mg/day) was associated with reductions in estrone and testosterone levels; however, DHEAS and femoral BMD were also decreased in RA patients who were not receiving corticosteroids. Reduced DHEAS levels in postmenopausal women with RA may increase their risk of osteoporosis.  相似文献   
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Migraine is a common, complex brain disorder whose biology is becoming better understood. Despite being the most disabling of the neurological disorders on a worldwide basis, headache disorders broadly, and migraine in particular, have poor research funding and a limited academic base. Given a modicum of investment, new targets, such as calcitonin gene‐related peptide–based mechanisms, and entirely novel neuromodulation approaches illustrate that much can be done to improve patient care. Genetics and neuroimaging combined with excellent clinical phenotyping and translational neuroscience approaches are set to transform life for a cohort of patients with these common brain disorders. Ann Neurol 2013;74:423–434  相似文献   
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Multiple breath inert gas washout (MBW) is gaining popularity for measurements of resting lung volume and ventilation inhomogeneity. Test reproducibility is an important determinant of the clinical applicability of diagnostic tests. The between‐test reproducibility of variables derived from MBW tests in newborn infants is unknown. We aimed to determine the within‐test repeatability and short‐term between‐test reproducibility of MBW variables in unsedated preterm infants. We hypothesized that measurements obtained within a 3‐day interval in clinically stable preterm infants would be reproducible and suitable for use as an objective clinical outcome measurement. In this cross‐sectional observational study, clinically stable hospitalized preterm infants whose parents had given informed consent for MBW studies were tested twice within 72 hr during quiet, unsedated sleep. Functional residual capacity (FRC), lung clearance index (LCI), and the first and second to zeroeth moment ratios (M1:M0; M2:M0) were computed from MBW traces obtained using a mainstream ultrasonic flowmeter and 4% sulphur hexafluoride (MBWSF6). Within‐test repeatability and between‐test reproducibility were determined. Within‐test repeatability (expressed as a coefficient of variability (Cv)) for differences between two and four replicate measurements on the same test occasion, were 9.3% (FRC), 9.0% (LCI), 7.6% (M1:M0), and 15.6% (M2:M0), respectively. The within‐test Cv's were not statistically different to the between‐tests Cv's, which were 7.7% (FRC), 10.3% (LCI), 6.1% (M1:M0), and 13.0% (M2:M0), respectively. Among unsedated preterm infants, between‐test reproducibility over a 3‐day interval was similar to within‐test repeatability. The wide limits of agreement may limit the application of these measures to detect a clinically significant change in condition in small preterm infants. Pediatr Pulmonol. 2010; 45:62–70. © 2009 Wiley‐Liss, Inc.  相似文献   
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