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51.
OBJECTIVE: The study was to determine whether being the macrosomic offspring of a mother without detected glucose intolerance during pregnancy has an impact on lipid profile, glucose homeostasis, and blood pressure during childhood. RESEARCH DESIGN AND METHODS: Plasma total, HDL, and LDL cholesterol; triglycerides; apolipoprotein (Apo) A-1, -B, and -E; lipoprotein (a); fasting glucose and insulin; homeostasis model assessment of insulin resistance (HOMA-IR) index; blood pressure; BMI; and detailed anthropometry were evaluated in 85 children aged 3-10 years old, born appropriate for gestational age (AGA; n = 48) and large for gestational age (LGA; n = 37) of healthy mothers. RESULTS: At the time of the assessment, body weight, height, skinfold thickness, BMI, waist circumference, and blood pressure did not differ between the LGA and AGA groups with the exception of head circumference (P < 0.01). There were no significant differences in plasma total or LDL cholesterol; triglycerides; Apo A-1, -B, or -E; lipoprotein (a); Apo B-to-Apo A-1 ratio; or glucose levels between the groups. The LGA group had significantly higher HDL cholesterol levels (P < 0.01), fasting insulin levels (P < 0.01), and HOMA-IR index (P < 0.01) but lower values of the glucose-to-insulin ratio (P < 0.01) as compared with the AGA group. CONCLUSIONS: Children born LGA of mothers without confirmed impaired glucose tolerance during pregnancy show higher insulin concentrations than AGAs.  相似文献   
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The purpose of this study was to compare various methods and criteria used to identify the anaerobic threshold (AT), and to correlate the AT obtained with each other and with running performance. Furthermore, a number of additional points throughout the entire range of lactate concentrations [La?] were obtained and correlated with performance. A group of 19 runners [mean age 33.7 (SD 9.6) years, height 173 (SD 6.3) cm, body mass 68.3 (SD 5.4)?kg, maximal O2 uptake (O2 max ) 55.2 (SD 5.9)?ml?·?kg?1?·?min?1] performed a maximal multistage treadmill test (1?km?·?h?1 every 3.5?min) with blood sampling at the end of each stage while running. All AT points selected (visual [La?], 4?mmol?·?l?1 [La?], 1?mmol?·?l?1 above baseline, log-log breakpoint, and 45° tangent to the exponential regression) were highly correlated one with another and with performance (r?>?0.90) even when there were many differences among the AT (P??1 [La?], 1 to 6?mmol?·?l?1 [La?] above the baseline, and 30 to 70° tangent to the exponential curve of [La?]) were also highly correlated with performance (r?>?0.90). These results failed to demonstrate a distinct AT because many points of the curve provided similar information. Intercorrelations and correlations between AT and performance were, however, reduced when AT were expressed as the percentage of maximal treadmill speed obtained at AT or percentage of O2 max . This would indicate that different attributes of aerobic performance (i.e. maximal aerobic power, running economy and endurance) are measured when manipulating units. Thus, coaches should be aware of these results when they prescribe an intensity for training and concentrate more on the physiological consequences of a chosen [La?] rather than on a “threshold”.  相似文献   
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Background Balloon dilatation of the oesophagus in children has been performed predominantly for treating strictures, which are the result of primary repair of oesophageal atresia, interposition surgery or restrictive Nissen's fundoplication. Reports of the use of this technique for alternative causes of stricture are few.Objective To report our experience and success with balloon dilatation of strictures due to caustic ingestion, achalasia, oesophagitis, congenital stenosis, and epidermolysis bullosa (EB) and to make comparisons with our treatment of patients with primary repair of oesophageal atresia (OA), as well as with reports in the English language literature.Materials and methods Retrospective review of fluoroscopically guided balloon oesophageal dilatation procedures in 19 patients over a 5-year period, and comparison of those performed for OA repair complications with those due to other diseases. The average radiation dose, per procedure, was calculated by a medical physicist.Results Ten patients had strictures as a result of primary repair of OA. Three patients had stricture as a result of EB, two from achalasia, two from caustic injury, one due to an oesophageal web and one from reflux oesophagitis. Our results show that the technique can also be curative for the last group and that it may be used intermittently to alleviate symptoms in ongoing diseases. We have not experienced any complications and have also calculated that, even with prolonged use of multiple procedures, the radiation exposure is comparable to other radiological techniques.Conclusions Patients with alternative causes for oesophageal stricture may be treated to resolution within 2 years using balloon dilatation. Ongoing diseases such as EB require ongoing dilatation, but balloon dilatation of strictures has been successful in alleviating swallowing difficulty. Patients with stricture from OA repair sometimes need ongoing dilatation. Radiation exposure for multiple procedures, over an extended period, is comparable to that from a single abdominal CT, and can be considered acceptable when repeat complex surgery is the alternative treatment option, or when ongoing incurable disease is the cause of the stricture.This paper was presented in a modified form at the 39th Annual Congress of ESPR, Bergen, Norway, June 2002  相似文献   
54.
Twenty-five premature infants (mean gestational age+/-SD, 31.4+/-1.9 weeks) were administered subcutaneously recombinant human erythropoietin (rHuEpo) at a dose of 300 u/kg of body weight three times a week beginning on the third day of life and continuing for 6 weeks. The controls (n=23) were premature infants with a mean gestational age of 32.2+/-2.3 weeks who did not receive rHuEpo. Haematological indices, haemoglobin and serum phosphate (Pi), and red blood cell (RBC) phosphate metabolites (ATP, 2,3-DPG, RBCPi) were tested monthly until the 6th month and thereafter at the 9th and 12th months of life. The level of serum soluble transferrin receptors (sTfR) correlated significantly with rHuEpo (p<0.05). The ratio of sTfR to log (ferritin) was significantly higher (p<0.001) in the infants treated with rHuEpo than the controls. Intracellular organic and inorganic Pi changes were not affected by the Epo administration. The RBC 2,3-DPG seemed adequate in infants receiving rHuEpo.  相似文献   
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OBJECTIVE: To estimate the diagnostic accuracy of chest radiography in the detection of chest lymphadenopathy in children with clinically suspected pulmonary tuberculosis. METHODS: DESIGN: Prospective cross sectional study. SETTING: A short stay ward in a children's hospital in South Africa. Patients: Consecutive children under 14 years of age admitted with suspected pulmonary tuberculosis. Diagnostic test: Antero-posterior and/or lateral chest x rays interpreted independently and blind to the reference standard by three primary care clinicians and three paediatricians, all with a special interest in tuberculosis. Reference standard: Spiral chest computed tomography (CT) with contrast injection. RESULTS: One hundred children (median age 21.5 months) were enrolled. Lymphadenopathy was present in 46 of 100 reference CT scans and judged to be present in 47.1% of x ray assessments. Overall sensitivity was 67% and specificity 59%. Primary care clinicians were more sensitive (71.5% v 63.3%, p = 0.047) and less specific (49.8% v 68.9%, p<0.001) than paediatricians. Overall accuracy was higher for the paediatricians (diagnostic odds ratio 3.83 v 2.49, p = 0.008). The addition of a lateral to an antero-posterior view did not significantly increase accuracy (diagnostic odds ratio 3.09 v 3.73, p = 0.16). Chance adjusted inter-observer agreement (kappa) varied widely between viewer pairs, but was around 30%. CONCLUSIONS: Detection of mediastinal lymphadenopathy on chest x ray to diagnose pulmonary tuberculosis in children must be interpreted with caution. Diagnostic accuracy might be improved by refining radiological criteria for lymphadenopathy.  相似文献   
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To understand the role of carotid chemoreceptor activity in the ventilatory responses to sustained hypoxia (30 min) the following measurements were made in cats anesthetized with alpha-chloralose: (1) carotid chemoreceptor and ventilatory responses to isocapnic hypoxia and to hypercapnia during hyperoxia; (2) carotid chemoreceptor responses to isocapnic hypoxia after dopamine receptor blockade; and (3) ventilatory responses to hypoxia after bilateral section of carotid sinus nerves (CSN). Transition to hypoxia (PaO2 approximately equal to 52 Torr) from hyperoxia gradually increased carotid chemoreceptor activity by ten fold and ventilation by two fold without any detectable overshoot. Termination of isocapnic hypoxia with hyperoxia (PaO2 greater than 300 Torr) at 30 min promptly restored the carotid chemoreceptor activity to prehypoxic level. Ventilation also decreased promptly, but remained above the control value. Induction of hypercapnia (from 31.8 Torr to 43.9 Torr) during hyperoxia was followed by a prompt increase in the chemoreceptor activity by four fold which subsequently diminished, and by a gradual four fold increase in ventilation. Termination of hypercapnia after 30 min was followed by a prompt return of chemoreceptor activity and by a slow return of ventilation to near control levels. Dopamine receptor blockade increased carotid chemoreceptor responsiveness to acute hypoxia but did not alter the response pattern during sustained hypoxia. After bilateral CSN section, ventilation decreased during maintained hypoxia. Thus, a stimulatory peripheral and inhibitory central effects of hypoxia could produce a biphasic ventilatory response to short-term hypoxia in the anesthetized cat with intact CSN but did not manifest it. The results suggest that the chemosensory input not only promptly stimulates ventilation but also prevents the subsequent depressant effect of hypoxia on the brain-stem respiratory mechanisms and hence presumably a biphasic ventilatory response in the anesthetized cat.  相似文献   
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