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This study was designed to compare the growth of Pakistani schoolchildren in the UK with the 1990 UK growth standards. Measurements of height, weight, and sitting height were performed on 785 Pakistani schoolchildren aged 5-14 years with the mean values for each age and sex being plotted on the UK growth standards. The results were expressed as SD scores relative to the 1990 reference data. The mean height for the boys was only 0.2 SD scores below the mean for the new growth standards with the mean height for the girls being 0.4 SD scores below the mean. The mean values for weight and body mass index were 0.3 and 0.5 SD scores less than the mean for boys and girls respectively. This study demonstrates that the growth of Pakistani schoolchildren in the UK is comparable to the 1990 UK growth standards with only minor differences. It is not safe to assume that short stature or low body weight in a Pakistani child is due to his or her ethnic background.  相似文献   
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Objectives: To evaluate the clinical usefulness of FDG-PET (fluoro-2-deoxy-glucose-positron emission tomography) in the detection of lymph node involvement and recurrences in patients with head and neck cancer. Study Design: Retrospective review of 38 patients with biopsy-proven head and neck cancers who underwent clinical, computed tomography (CT), and FDG-PET examinations. Twenty-five patients were studied prior to therapy and 13 patients were evaluated for disease recurrence. Methods: All patients were operated and clinical data, CT, and FDG-PET results were correlated with histopathological findings. Results: All primary tumors in 25 patients were detected, with the exception of one small superficial localization of the epiglottis. Histopathological examination showed lymph node involvement in 10 patients; PET detected lymph node involvement in five. FDG-PET found one case of nodal disease not identified by clinical and CT examination. With so few cases, this could be anecdotal. Five false-negative results (microscopic lymph node involvement) and two false positives were noted. Twelve of 13 patients with recurrent disease were correctly identified with FDG-PET. FDG-PET was the only imaging technique to identify local recurrence in two patients and lymph node involvement in two others. One false-positive result occurred in a patient with a foreign body granuloma. Conclusions: FDG-PET is a useful diagnostic modality for the detection of recurrent tumors and, in selected cases, precise lymph node involvement. The best way to further investigate the utility of clinical FDG-PET is in the follow-up of treated patients. Key Words: FDG-PET, head and neck cancer, lymph node metastases, recurrent disease. Laryngoscope, 108:1578–1583, 1998  相似文献   
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We used the CA-77 cell, a murine C-cell line derived from a medullary thyroid carcinoma, to study the effects of glucocorticoids, calcium, and vitamin D metabolites on calcitonin (CT) gene expression. Total RNA was isolated, and CT and CT gene-related peptide (CGRP) mRNAs were measured by Northern hybridizations using specific probes. A control mRNA probe (cyclophilin) was used to quantitate the specificity of the changes in CT and CGRP mRNAs. The CA-77 C cell line cultured in basal conditions with a medium deprived of fetal calf serum, but was supplemented by insulin, expressed mainly the CGRP mRNA. Dexamethasone was found to increase both CT and CGRP mRNAs in a time- and dose-dependent way without changing the alternative splicing. A slight but significant increase in the steady-state CT mRNA level was found 3 days after addition of 10(-10) M dexamethasone; the same dose slightly decreased the CGRP mRNA level; concentrations of dexamethasone > or = 10(-9) M elevated both mRNAs. A twelve-fold increase for CT mRNA, and an eightfold increase in CGRP mRNA occurred 3 days after administration of 10(-6) M dexamethasone. Kinetic data revealed inductions of both mRNAs 24 hours after exposure to 10(-7) M dexamethasone, and highest CT and CGRP mRNAs levels were observed after 72 hours of treatment. Calcium from 1-4 mM in short-term (1 hour and 4 hour) or long-term stimulations (1 day and 4 days), with or without dexamethasone cotreatment was ineffective. CT and CGRP mRNAs levels were both half-reduced 48 hours after addition of 10(-7) M 1,25-dihydroxycholecalciferol; this effect was transient, as it disappeared 2 days later.  相似文献   
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To investigate bronchial permeability in asthma, we measured the bronchial clearance of 113mIn-DTPA in seven asthmatics during and after an acute attack of asthma, seven asthmatics with chronic airflow limitation, and seven asthmatics without airflow limitation but with bronchial hyperresponsiveness to methacholine. We compared these results with those from seven normal subjects, seven patients with chronic bronchitis and bronchial infection, and seven patients with emphysema. An aerosol of 113mIn-DTPA was produced with a spinning disc to ensure a predominantly bronchial deposition of inhaled particles (6.3 microns MMAD). Radioactivity over the chest was recorded with a gamma-camera for 10 min after the subject inhaled the aerosol. Central regions of interest were selected, and the logarithm of the radioactivity was plotted against time; bronchial clearance of 113mIn-DTPA was calculated as the negative slope of the regression line. Clearance was substantially higher in asthmatics during their acute attacks than in all other groups (p less than 0.0001), and it decreased toward normal levels after recovery from the acute episode. The bronchial clearance of 113mIn-DTPA in all other groups did not differ from normal. We conclude that the bronchial clearance of 113mIn-DTPA is increased in asthmatics during attacks of asthma but in the stable state is not related either to bronchial hyperresponsiveness or to airflow limitation. Our findings are best explained by an increase in permeability of the bronchial mucosa of asthmatics during acute attacks.  相似文献   
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The present article reports a case involving an immunocompetent, previously well child who, despite two previous doses of inactivated poliovirus vaccine, developed severe flaccid paralysis consistent with polio after receiving oral polio vaccine.  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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