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Head Growth (head + growth)
Selected Abstracts,Head growth and cranial assessment at neurological examination in infancy'DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 6 2003Article first published online: 13 FEB 200 No abstract is available for this article. [source] Sexual selection is not the origin of long necks in giraffesJOURNAL OF ZOOLOGY, Issue 4 2009G. Mitchell Abstract The evolutionary origin of the long neck of giraffes is enigmatic. One theory (the ,sexual selection' theory) is that their shape evolved because males use their necks and heads to achieve sexual dominance. Support for this theory would be that males invest more in neck and head growth than do females. We have investigated this hypothesis in 17 male and 21 female giraffes with body masses ranging from juvenile to mature animals, by measuring head mass, neck mass, neck and leg length and the neck length to leg length ratio. We found no significant differences in any of these dimensions between males and females of the same mass, although mature males, whose body mass is significantly (50%) greater than that of mature females, do have significantly heavier (but not longer) necks and heavier heads than mature females. We conclude that morphological differences between males and females are minimal, that differences that do exist can be accounted for by the larger final mass of males and that sexual selection is not the origin of a long neck in giraffes. [source] The Rett Syndrome Behaviour Questionnaire (RSBQ): refining the behavioural phenotype of Rett syndromeTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 8 2002Rebecca H. Mount Background: Although physical features, including loss of hand skills, deceleration of head growth, spasticity and scoliosis, are cardinal features of Rett syndrome (RS), a number of behavioural features are also associated with the disorder, including hand stereotypies, hyperventilation and breath holding. No study has tested the specificity of these behavioural features to individuals with RS, compared to individuals with severe to profound mental retardation (SMR). Method: A novel checklist of characteristic RS behavioural and emotional features, the Rett Syndrome Behaviour Questionnaire (RSBQ), was developed to test the type and specificity of behavioural features of RS against those found in girls with SMR. Results: After controlling for the effects of RS-related physical disabilities, the RSBQ discriminated between the groups. Some aspects of the behaviours found to be specific to RS are included in the necessary or supportive RS diagnostic criteria, notably hand behaviours and breathing problems. Additional behavioural features were also more frequently reported in the RS than the SMR group, including mood fluctuations and signs of fear/anxiety, inconsolable crying and screaming at night, and repetitive mouth and tongue movements and grimacing. Conclusions: Full validation of the scale requires confirmation of its discriminatory power and reliability with independent samples of individuals with RS and SMR. Further delineation of the specific profile of behaviours seen in RS may help in identification of the function of the MECP2 gene and in improved differential diagnosis and management of individuals with RS. [source] Head circumference and linear growth during the first 3 years in treated congenital hypothyroidism in relation to aetiology and initial biochemical severityCLINICAL ENDOCRINOLOGY, Issue 1 2004Sze May Ng Summary aims, To determine the head circumference and linear growth in children with congenital hypothyroidism (CH) during the first 3 years of life in relation to the aetiology of CH and initial biochemical severity of thyroid function. methods, We examined the head circumference and linear growth of 125 patients with CH from diagnosis up to 3 years of age. All infants had radionuclide scans prior to treatment. Patients were categorized into athyreosis, ectopia and dyshormonogenesis. Occipito-frontal circumference (OFC) SD, length SD, initial plasma TSH, initial plasma thyroxine (T4) and age of suppression of plasma TSH were compared between the groups. Multiple linear regression analysis was used to determine factors affecting OFC SD at 3 years of age. results, There were 125 children in the study: athyreosis (n = 34), ectopia (n = 73) and dyshormonogenesis (n = 18). No difference was found in gestation, birth weight, age of starting L-T4 and initial dose of L-T4 in mcg/kg/day between groups. Confirmatory plasma total T4 at diagnosis was significantly lower for athyreosis when compared with ectopia and dyshormonogenesis. Median values for confirmatory TSH were significantly lower in dyshormonogenesis compared with the other two groups. At diagnosis, OFC were similar in all three groups. Children with athyreosis showed significantly larger OFCs compared with ectopia and dyshormonogenesis from 1 to 3 years. Length SD was within 1 SD of normal population standards at diagnosis and did not differ between the three groups throughout the 3 years. Spearman's correlation for OFC SD at 3 years of age showed a significant negative correlation with initial confirmatory plasma T4 (r = ,0·35, P = 0·01). Multivariate analysis for OFC SD at 3 years of age showed confirmatory T4 as the only independent risk factor. conclusion, Children with athyreosis showed significantly larger OFC from 1 to 3 years of age compared with ectopia and dyshormonogenesis, independent of linear growth. Our data shows that initial confirmatory T4 at diagnosis is an independent factor influencing head growth in the first 3 years of life. [source] | ||||||||||