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Single-locus DNA probes for tandem repeat sequences are now used in conjunction with particular endonucleases to characterize heritable restriction fragment lengths in parentage tests. Southern blots of this type, however, demonstrate only two attributes of an allele: its length and the presence of nucleotide sequences that are complementary to the probe. Not all restriction fragments of the same apparent length that react with the same probe are identical. Differences between comigrating fragments can be detected by the selection of a restriction enzyme that recognizes sites in a subset of the repeat sequences, and the information content of these loci is therefore increased. This report describes a paternity case in which two brothers appeared, after DNA phenotyping using Hinf I, to be the father. A second phenotyping using Hae III excluded one of the brothers. 相似文献
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FREDERIC TELLIEZ VERONIQUE BACH GERARD DEWASMES RE LEKE & JEAN-PIERRE LIBERT 《Journal of sleep research》1998,7(1):31-39
Sleep processes and body temperature regulation of neonates are never taken into account in the evaluation of nutrients, although these functions are implicated in the regulation of energy metabolism and are influenced by the nutritional state and its metabolic consequences. Medium-chain triglycerides (MCT) are currently used in paediatric units during the first weeks of because they are considered to be a rapid source of energy, easy to assimilate for growing premature infants, whose digestive function is immature. However, no study has described the thermic effect of these nutrients on body temperature regulation and sleep. The present study aimed at analysing the influence of three feeding formulas with different content of MCT on sleep processes and on thermoregulation of neonates fed until desired intake was reached. Whatever the thermal conditions (thermal equilibrium or cool environment), the MCT-fed groups had higher body temperatures and than groups fed without MCT, for whom total sleep time was reduced at thermal equilibrium. In this group, the large amount of quiet sleep seems to favour a strategy of conserving energy . Higher energy expenditure in MCT-fed groups is not harmful to growth rate since nutritional efficiency is even better reflected by a larger body mass gain. The thermic effect of MCT contributes to lessening the vulnerability of neonates exposed to low incubator temperatures. 相似文献
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Efficacy study of the small-bowel examination 总被引:8,自引:0,他引:8
89.
Aspects of the bioaccumulation of heavy metals are reviewed and possible evidence of homeostasis is highlighted. Examination
and analysis of olive (Olea europaea L.) trees growing in close proximity to a copper dominated spoil tip dating from at least 2000 years BP, on the island of
Cyprus, revealed both bioaccumulation and partitioning of copper, lead and zinc in various parts of the tree. A factor to
quantify the degree of accumulation is illustrated and a possible seed protective mechanism suggested. 相似文献