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61.
Enteral nutrition is increasingly used to provide nutritional support for children in hospital and at home. No suitable formula is available for preschool children, however, and until recently a modular feed has been prepared. The hypotheses were examined that the use of a modular feed is associated with increased bacterial contamination, and that contamination is more common in the home than in hospital. Thirty five children receiving enteral nutrition initially in hospital and subsequently at home were allocated randomly to receive either a modular feed or a newly available sterile ready to use paediatric feed. Samples of feed were taken from the nutrient container immediately after filling and at the end of feeding. The results show that feed contamination is common in hospital and at home, but significantly more so at home. The data indicate the importance of hygiene training for parents and the desirability of a ready to use formula.  相似文献   
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The relation of obesity to clustering of systolic blood pressure, fasting insulin, and ratio of low and very low density lipoprotein cholesterol to high density lipoprotein cholesterol [LDL-C + VLDL-C)/HDL-C) was investigated in 3,503 subjects aged 5-24 years in Bogalusa, Louisiana, from September 1981 to September 1983. Risk ratios (RR) were calculated as the number of subjects with risk factor variables in the upper tertile divided by the expected number. The variables showed strong clustering (RR = 3.1); however, after adjusting for obesity, clustering of systolic pressure, (LDL-C + VLDL-C)/HDL-C, and insulin was reduced (RR = 1.3). Lean subjects (lower tertile of obesity) showed less clustering than expected (RR = 0.4), while more obese subjects (upper tertile of obesity) had greater clustering than expected (RR = 3.1). Furthermore, trunk fat deposition (subscapular skinfold) had a greater impact on clustering at high levels than limb fat deposition (triceps skinfold). Since obesity is related to clustering of risk factor variables in children and young adults, the prevention of the onset of obesity in early life may be important to reducing the risk of coronary heart disease in later life.  相似文献   
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To determine whether CRH is the sole mediator of ACTH release during exercise, five men and five women were given, in a subject-blinded random manner at separate visits, both a 6-h infusion of ovine CRH (1 microgram/kg.h) and a saline infusion as a placebo. After the fourth hour of each infusion, when plasma concentrations of ovine CRH were sufficiently elevated to saturate the capacity of the corticotroph to respond further to CRH, each subject completed a high intensity intermittent run. Plasma ACTH and cortisol levels increased significantly during the CRH infusion from 4.6 +/- 0.8 (mean +/- SE) to 8.6 +/- 1.6 pmol/L and from 361 +/- 39 to 662 +/- 70 nmol/L, respectively (P less than 0.05). Despite elevated preexercise cortisol levels during the CRH infusion, plasma ACTH rose to 32.0 +/- 8.5 pmol/L after exercise. During the saline infusion, plasma ACTH rose from 3.4 +/- 0.6 pmol/L before exercise to 18.1 +/- 4.2 after exercise. Time-integrated responses for postexercise values of ACTH and cortisol were higher during the CRH infusion than during the saline infusion (P less than 0.05). No significant exercise-induced differences in heart rate or plasma concentrations of lactate, epinephrine, and norepinephrine were observed between the two tests. The findings suggest that some factor(s) in addition to CRH causes ACTH release during exercise. Vasopressin, produced by the magnocellular and/or parvocellular neurons of the hypothalamus, is a likely candidate.  相似文献   
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Cardiovascular defects are common in diabetic offspring, but their etiology and pathogenesis are poorly understood. Extracellular matrix accumulates in adult tissues in response to hyperglycemia, and transforming growth factor-beta1 (TGF beta1) likely mediates this effect. The objective of this study was to characterize TGF beta expression in the organogenesis-stage mouse heart and to evaluate TGF beta and fibronectin expression in embryonic mouse heart exposed to hyperglycemia. Prominent TGF beta1, and minimal TGF beta2 or TGF beta 3, protein expression was demonstrated in embryonic day (E) 9.5-E13.5 hearts. Hyperglycemia for 24 hr produced significantly increased fibronectin, slightly increased TGF beta1, and unchanged TGF beta2 or TGF beta 3, by immunohistochemistry. Increased TGF beta1 was demonstrated by enzyme-linked immunosorbent assay in embryonic fluid and isolated hearts after hyperglycemia for 24 hr, but not 48 hr. Hyperglycemia increased fibronectin protein and mRNA expression in embryonic hearts after 24 hr, and pericardial injection of TGF beta1 also increased fibronectin mRNA in the embryonic heart. It is proposed that TGF beta1 and fibronectin may play a role in diabetes-induced cardiac dysmorphogenesis.  相似文献   
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Biochemical indices of selected trace minerals in men: effect of stress   总被引:1,自引:0,他引:1  
Plasma zinc, iron, copper, and selenium and selected blood proteins were measured in 66 men before (BHW) and after (AHW) a 5-d period of sustained physical and psychological stress called Hell Week. Recovery blood samples were obtained from 26 men 7 d after Hell Week. Dietary intakes were determined BHW and during Hell Week; zinc, iron, copper, and selenium intakes during Hell Week averaged 23.6 +/- 3.4 mg/d, 35.4 +/- 3.9 mg/d, 3.0 +/- 0.5 mg/d, and 92.5 +/- 26.7 micrograms/d, respectively. C-reactive protein was detected in only five subjects BHW and in all subjects AHW. Zinc, iron, selenium, and albumin decreased by 33%, 44%, 12%, and 9%, respectively, whereas ferritin, ceruloplasmin, and creatine kinase concentrations increased AHW by 59%, 8%, and 266%, respectively. Haptoglobin concentrations increased 57% in 30 subjects but decreased 32% in 23 subjects AHW. The biochemical changes were transitory because protein (except ferritin) and mineral concentrations were similar to BHW values 7 d after Hell Week. Hell Week induced changes characteristic of an acute-phase response in physically active men.  相似文献   
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In a double blind cross-over study, 28 patients, 5 male and 23 female, aged 31 +/- 14 years, after a run-in period of 8 weeks, were treated for 3 months with acetylsalicylic acid and for another 3 months with metoprolol, both in a prophylactic mode. Attack frequency was reduced significantly with both therapeutic regimens (ASA p less than 0.001, metoprolol p less than 0.00005). Reduction of attacks below 50% was seen with metoprolol in 14 cases, and with ASA in three cases. Even though ASA was of statistically significant efficacy in migraine prophylaxis, it clearly is not the drug of first choice in migraine prophylaxis.  相似文献   
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