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ObjectiveThe aim of this study was to assess the nutritional zinc (Zn) status of elite swimmers during different training periods.MethodsA longitudinal paired study was performed at the University of Sao Paulo in eight male swimmers 18 to 25 y old who had been swimming competitively at the state and national levels for at least 5 y. The swimmers were evaluated over a total period of 14 wk: before the basic and specific preparatory period (BSPP-baseline), at the end of the basic and specific preparatory period (post-BSPP), and at the end of the polishing period (PP). Levels of Zn were determined in the plasma, erythrocyte, urine, and saliva by atomic absorption spectrophotometry. Anthropometric measurements and a 3-d food record were also evaluated.ResultsThe median plasma Zn concentration was below the reference value in all training periods (BSPP-baseline 59 μg/dL, post-BSPP 55.9 μg/dL, after PP 58.8 μg/dL, P > 0.05), as were threshold values for erythrocytes (BSPP-baseline 36.5 μg of Zn/g of hemoglobin, post-BSPP 42 μg of Zn/g of hemoglobin, after PP 40.7 μg of Zn/g of hemoglobin, P > 0.05), urinary Zn (BSPP-baseline 280 μg/24 h, post-BSPP 337 μg/24 h, after PP 284 μg/24 h, P > 0.05), and salivary Zn (BSPP-baseline 66.1 μg/L, post-BSPP 54.1 μg/L, after PP 79.7 μg/L, P > 0.05). Salivary Zn did not correlate with plasma and erythrocyte Zn levels.ConclusionThe results suggest that the elite swimmers studied presented a possible Zn deficiency and that salivary Zn was not adequate to evaluate the Zn nutritional status.  相似文献   
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Over the last years, ambulatory blood pressure monitoring has been introduced into the pediatric population, contributing to a significant increase in the bulk of knowledge of crucial clinically relevant issues. Guidelines have established the currently known conditions where ambulatory blood pressure monitoring is useful and where it will provide additional information in children and adolescents. How common and important the intra-individual differences are within clinical and ambulatory blood pressure is the keystone to the use of ambulatory blood pressure monitoring as a diagnostic tool. By using not only office, but also ambulatory blood pressure, four possible situations arise. Two of these have values in agreement for normotension or hypertension. Two have values that are discrepant. The latter two are known as white coat and masked hypertension. The relationship with hypertension-induced organ damage, the prognostic value and the assessment of treatment goals are key issues of ambulatory blood pressure monitoring. In children, the accurate identification of hypertension at the earliest possible age would, therefore, give health-care providers the opportunity to initiate preventive measures, thereby reducing the chance of developing end-organ damage and its attendant morbidity and mortality.  相似文献   
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Every year, a large number of individuals become dependent on mechanical ventilation because of a loss of diaphragm function. The most common causes are cervical spinal trauma and neuromuscular diseases. We have developed an experimental model to evaluate the performance of electrical stimulation of the diaphragm in rabbits using single-channel electrodes implanted directly into the muscle. Various current intensities (10, 16, 20, and 26 mA) produced tidal volumes above the baseline value, showing that this model is effective for the study of diaphragm performance at different levels of electrical stimulation  相似文献   
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Purpose: To evaluate the positivity rate of temporal artery biopsies (TAB) performed in suspects of giant cell arteritis (GCA) and to study the epidemiological and clinical factors associated to the biopsy result. Methods: A retrospective, multicenter, case–control study was performed, including three hundred and thirty‐five patients who underwent TAB for a suspicion of GCA from 2001 to 2010. Clinical, epidemiological and pathology data were recovered from the patients’ clinical records. Histologic diagnosis of GCA was made when active inflammation or giant cells were found in the arterial wall. Results: Eighty‐one biopsies (24.2%) were considered positive for GCA. Clinical factors independently associated to TAB result in a logistic regression analysis were temporal cutaneous hyperalgesia (OR = 10.8; p < 0.001), jaw claudication (OR = 4.6; p = 0.001), recent‐onset headache (OR = 4.4; p = 0.001), decreased temporal pulse (OR = 2.8; p = 0.02), pain and stiffness in neck and shoulders (OR = 2.3; p = 0.05), unintentional weight loss (OR = 1.33; p = 0.003) and age (OR = 1.085; p = 0.004). Other factors such as length of the surgical specimen (OR = 1.079; p = 0.028) and erythrocyte sedimentation rate (OR = 1.042; p < 0.001) were also statistically significant. The model was accurate (C‐index = 0.921), reliable (pHosmer–Lemeshow = 0.733) and consistent in the bootstrap sensitivity analysis. No significant association was detected between TAB result and number of days of previous systemic corticosteroid treatment (p = 0.146). However, an association was observed between TAB result and the total accumulated dose of previous systemic corticotherapy (p = 0.043). Conclusions: Exhaustive anamnesis and clinical examination remain of paramount importance in the diagnosis of GCA. To improve the yield of TAB, it should be performed specially in older patients with GCA‐compatible clinic. TAB could be avoided in patients with an isolated elevation of acute phase reactants, without GCA‐compatible clinic.  相似文献   
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Introduction and objectivesLaryngeal electromyography, together with clinical evaluation, is a valuable tool in voice disorder management. It assesses the integrity of laryngeal nerves and muscles, contributing to the diagnosis of many diseases, especially laryngeal movement disorders. Our purpose was to describe the experience of the first Spanish series with laryngeal electromyography in evaluating voice disorders.MethodsA prospective study was designed to evaluate laryngeal movement disorders with laryngeal electromyography. Both the cricothyroid and thyroarytenoid muscles were tested routinely and, in some cases, the posterior cricoarytenoid muscle. The laryngeal electromyography technique and result interpretation were performed by a laryngologist and a neurophysiologist.ResultsWe included 110 patients, with the most common symptom being dysphonia. Laryngeal electromyography was performed in 85% of cases. Primary diagnosis before electromyography was laryngeal immobility. Positive predictive value for diagnosis in cases of paralysis was 88%.ConclusionsLaryngeal electromyography is a useful adjunct, together with clinical evaluation, for diagnosis and management of motion abnormalities in the larynx in patients who present with dysphonia.  相似文献   
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The most important advances in chronic pancreatitis concern its etiopathogenesis, nutritional aspects, and improvements in diagnostic techniques and some treatment options. In the etiopathogenesis of this disease, the importance of smoking and its association with alcohol have been confirmed. Exocrine pancreatic insufficiency (EPI) secondary to chronic pancreatitis is associated with bone metabolism alterations (osteopenia and osteoporosis), a reduction in liposoluble vitamins and alterations in essential amino acid levels. Endoscopic ultrasound has been confirmed as the most highly developed technique for the diagnosis of chronic pancreatitis, especially due to new image optimization technologies. Breath tests for the diagnosis of EPI continue to be developed (optimization of the C-13 mixed triglyceride test and the development of a new test based on C-13-labelled bicarbonate determination). Modest results in pain treatment have been achieved with the use of antioxidants, pancreatic enzymes and/or intravenous secretin. The association of chronic pancreatitis with pancreatic cancer requires strict follow-up, especially in patients with inflammatory masses in the context of chronic pancreatitis.  相似文献   
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