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141.
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A longitudinal study evaluating the degree of rotation of the bimalleolar axis of tibia and fibula at birth, 6 month, 12 months and 24 months revealed a gradual statistically significant external rotation from a mean of 4 degrees at birth to a mean of 11 degrees at 24 months. There was no correlation with the sex or race of the child or with the age at which the child began independent walking. It is concluded that this external rotation is a part of normal growth and development of the infants' lower extremities. 相似文献
143.
GF Melson 《Canadian Metallurgical Quarterly》1976,43(1):107-114
Two methods of assessing personal space in young children were examined in a group of 24 boys and 24 girls, aged 3 to 6 yr. When sex of peer figures and affect attributed to them were varied, 3-yr.-olds made distance-cue judgements based on affect but failed to use affect cues in structuring personal space. However, 4- to 6-yr.-olds readily perceived and used distance to communicate the affective quality of peer relations. On both measures, perception of distance cues increased with age. Only girls also used sex of figures as a social cue in depicting appropriate distances. 相似文献
144.
GF Nevskaia GM Abramova EV Ginsburg DN Ishmukhametova AS Skorik 《Canadian Metallurgical Quarterly》1977,11(3):67-70
The paper presents the results of a 6-year investigation of hemopoiesis of dogs which were exposed to double irradiations (with a 1.5-month interval) with protons at a dose of 350 rad when different parts of the body (head, chest, abdomen, pelvis) were shielded. Throughout the entire period the dogs showed moderate leucopenia and by the end of the investigation insignificant anemia. The dogs irradiated with shielded abdomen displayed disturbances in bone marrow hemopoiesis, whereas other dogs exhibited relative, although transient, normalization. All the dogs showed a significant decrease of erythropoiesis and a relative stability of leucopoiesis as well as a significant elevation of the number of reticulocytes, monocytes and plasmocytes 5.5 year after irradiation. 相似文献
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In Switzerland the birch tree (Betula verrucosa) major allergen Bet v 1 and the grass (Phleum pratense) pollen major allergen Phl p 5 are of particular relevance for inducing pollinosis. In this study, the protein and major allergen contents of aerosols of different aerodynamic diameters were determined. The aerosols were sampled by Andersen-Impactors and submitted to protein assays and allergen assays (ELISA) specific for Bet v 1 and Phl p 5. The total protein, Bet v 1 and Phl p 5 concentrations were correlated with the corresponding pollen counts. The presence of Bet v 1 in smaller aerosol fractions was demonstrated before and after birch pollen was counted, especially in the lower particle size ranges. 相似文献
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Ventilatory acclimatization to sustained hypoxia (VASH) is the time-dependent increase in ventilation that occurs during prolonged exposure to hypoxia. We tested the hypothesis that carotid body (CB) dopaminergic mechanisms are down-regulated during VASH, which would allow CB afferent discharge and ventilation to increase beyond the initial response to hypoxia. Domperidone (DOM; 1.0 mg.kg-1) was administered intravenously to block CB dopamine (DA) receptors after VASH was complete in awake goats. DOM caused a significant augmentation of the ventilatory response to hypoxia in acclimatized goats, failing to support the hypothesis. We conclude that inhibitory CB dopaminergic function is not significantly reduced following prolonged hypoxia, and that down-regulation of CB dopaminergic mechanisms may not be involved in VASH in the goat. 相似文献