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Clefts of the lip and palate, separately or in combination, are among the most frequent congenital defects seen today. Their etiology is heterogeneous and may include hormonal factors, which suggest the possibility of growth effects. Whether affected children are smaller than others has not been determined. We recently showed that growth status is associated with type of cleft. We hypothesized genetic alterations in metabolic pathways that alter prenatal growth, producing clefts; some of these alterations also alter postnatal growth. Since the levels of growth-regulating hormones change during ontogeny, we expected age differences in the degree of growth deficit seen. To test this hypothesis, we examine here the cross-sectional means and distributions of standard deviation (z) scores for height and body mass indices (BMIs) for 144 children with the diagnoses unilateral cleft lip and palate (uCLP) and isolated cleft palate (iCP). We find that alteration in growth status is associated with age group as well as sex and diagnosis.  相似文献   
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Variations in moisture and substrate in preharvest corn kernels and cottonseed were linked with the ability of Aspergillus parasiticus to infect the seed and produce aflatoxin. Osmotic pressures and moisture content (MC) levels of developing starch-rich corn kernels and lipid-rich cottonseed were determined. For in vivo studies, corn kernels and cottonseed were inoculated with A. parasiticus conidia and retained on plants through maturation. For in vitro studies, samples of corn kernels and cottonseed were collected at various stages, sterilized, inoculated, incubated for 2 weeks, and assayed for toxin. Aflatoxin levels were highest in corn kernels inoculated at 28 days postflowering (52% MC) in both the in vivo and in vitro tests. Toxin concentrations in cottonseed were greatest with inoculation at 35 days postflowering (70% MC) in seed retained on the plant, but toxin accumulation continued to increase with the maturity of the seed inoculated in cottonseed used in the in vitro trials. Moisture and substrate conditions in the midrange of seed development provided optimum conditions for fungal development and toxin production in seed retained on the plant.  相似文献   
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A chromoprotein responsible for the blue coloration of the hemolymph in the spined soldier bug, Podisus maculiventris (Say), was isolated and identified as lipophorin. With the exception of its blue color the lipoprotein shares similar molecular characteristics with the hemolymph lipophorins of other Hemipterans and insects of several different orders. Its ability to carry a blue chromophore, biliverdin IX γ, adds a new feature to this multifunctional lipoprotein. © 1992 Wiley-Liss, Inc.  相似文献   
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