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OG Brooke 《Canadian Metallurgical Quarterly》1980,44(1):13-23
1. Energy balances were performed on sixteen low birth weight preterm infants over 7-10 d periods on a standard low-solute infant formula (2600 kJ/l), and on four high-energy formulas, providing different energy densities up to 3760 kJ/l. In two of the high-energy formulas the additional fat energy was provided by peanut oil, and the other two by medium chain triglycerides (MCT). Anthropometric measurements and metabolic rate (MR) determinations were made during the balance periods. 2. Mean energy retention on the standard formula was 66% of the intake and declined to below 50% on the two feeds providing the highest energy. Extensive energy balance data on the standard formula are available for reference. 3. Net absorption of dietary energy increased on all the high-energy formulas, rising from 362 kJ/kg per d on the standard formula to 453 kJ/kg per d on the highest energy-formula (P < 0.001). There was no advantage in using MCT. 4. Net absorption of dietary energy improved with advancing maturity, irrespective of the formula. 5. In spite of the increased dietary energy retention, there was no increase in growth rate during periods of feeding with the high-energy formulas. 6. Fasting and postprandial MR increased by 10.4 and 12.8% respectively on the highest energy feeds. 7. It is concluded that, at least in the short term, this type of high-energy feeding increases MR at the expense of growth and thus is probably of no advantage to the infant. 相似文献
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The theory of optical gain in highly doped semiconductors employed for semiconductor lasers is developed based on the Green function approach. With the help of the analytical expression obtained for optical gain, the threshold properties of semiconductor lasers and their dependence on concentration of doping impurities and on temperature are studied. Results of numerical calculations of threshold characteristics for the most interesting cases are presented. 相似文献
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The clousness of membrane of rat brain mitochondria isolated in Krebs-Ringer's solution was broken by suspending the mitochondria in distilled water. Function characteristics of lyzed organells did not decrease but were somewhat higher than those of the organells suspended in Krebs-Ringer's solution. The results were discussed in relation to the question of the role of clousness of the mitochondrial membrane in the mechanism of oxidative phosphorylation. 相似文献
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OG da Silva Filho RC Carvalho Lauris L Capelozza Filho G Semb 《Canadian Metallurgical Quarterly》1998,35(2):111-119
With recent advances in DNA technology, questions have arisen as to how this technology should be appropriately used. In this article, results obtained from a survey designed to elicit attitudes of college students to prenatal testing and gene therapy for human attributes and psychiatric conditions are reported. The eleven hypothetical disease phenotypes included schizophrenia, alcoholism, tendency toward violent behavior, attention deficit/hyperactivity disorder, depression requiring medical treatment, obesity, involvement in "dangerous" sports activities, homosexuality, borderline normal IQ (80-100), proportional short stature, and inability to detect perfect pitch. Most students supported prenatal genetic testing for psychiatric disorders and behavior that might result in harm to others (i.e., tendency towards violent behavior) and found prenatal genetic testing for human attributes less desirable. However, the lack of unilateral agreement or disagreement toward any one condition or attribute suggests the potential difficulties ahead in the quest for guidelines for the application of new technologies available to manipulate the human genome. 相似文献
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A patient with a 20-year history is presented as a classic example of erythema elevatum diutinum, with a dramatic response to dapsone therapy, and with interesting features of improvement during pregnancies and occurrence of giant cell tumors of soft tissue, neither of these latter features having been previously reported. 相似文献
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