PubMed Health⌕ Search

Biomedical subjects

A F Roche

Publications and source records attributed to A F Roche.

At least 91 records · Page 5Linked to original sources
PubMed1985

Parent-specific adjustments for evaluation of recumbent length and stature of children.

A clinical "parent-specific" method for evaluating recumbent length and stature of children, allowing for the stature of parents, is presented. This method uses midparent stature and allows adjustment of recumbent length (birth to 3 years) and stature (3 to 18 years) of US children relative to National Center for Health Statistics growth charts. The method is based on parent-child relationships for 586 midparent-child pairs participating in the Fels Longitudinal Study, and on more than 16,000 serial measurements of recumbent length and stature. The method provides a clinical tool to separate the normal genetic contribution of parental stature to stature of children from other factors that affect stature such as malnutrition or disease.

Adolescent↗
PubMed1984

A comparison of methods for measuring cortical bone thickness.

Repeated measures of periosteal and endosteal widths of the left second metacarpal from two samples of radiographs were made independently with either a dial caliper or an electronic digitizer connected to a microcomputer. In addition, periosteal and endosteal bone widths of a common sample of radiographs were measured with dial calipers and the electronic digitizer. Dial calipers and an electronic digitizer are both very reliable, but intraobserver errors produced with the use of the digitizer are significantly less than those produced with the use of dial calipers. However, measurements made with the electronic digitizer are systematically larger than corresponding widths measured with dial calipers, but this difference is very small.

Anthropometry↗
PubMed1984

Estimating the recombination frequency for the PTC-Kell linkage.

Two data sets are analyzed for linkage between the PTC and Kell blood group loci. The original report of close linkage for these loci was that of Conneally et al. (1976), where the maximum likelihood estimate of theta was 0.05. These two new data sets give a combined maximum likelihood estimate of theta m = f = 0.28. Estimating the recombination frequency for the sexes separately gave theta m = 0.29, theta f = 0.23. The combined maximum likelihood estimate over all published data sets including this report is theta m = f = 0.14, Zmax = 8.94. There is statistically significant evidence of heterogeneity among the published studies.

Blood Group Antigens↗
PubMed1984

Research progress in the field of body composition.

A broad review is presented of the changes in "state of the art" in body composition between 1963 and 1983, together with suggestions for future research. Consideration is given to the development of equations to estimate body density from anthropometry with special reference to the limitations of the stepwise approach and the need to consider power functions. The advantages of the maximum R2 method and the potential of ridge regressions to extend the applicability of estimation equations is discussed. During the past decade, there has been considerable interest in selecting indices of weight and stature, with suitable powers, for use as measures of obesity. Such indices are of doubtful value in children and not all methods applied to adults have been appropriate. Many consider frame size fundamental to judgments of the normality of weight in adults. There is merit in this concept but we lack a measure of frame size that explains a considerable part of the variance in body fat unaccounted for by weight and stature. Among the many studies of adipocytes, those of size are more valid than those of number, but there are problems related to the distribution of sizes within samples and the selection of sampling sites.

Adipose Tissue↗
PubMed1984

Body size, subcutaneous fatness and total body fat in older adults.

In a sample of healthy adults (24 men, 21 women; 54 to 85 years of age) anthropometry was collected and body density measured by underwater weighing. Estimates of body fat were computed from body density. The men were significantly larger than the women in body size and have significantly less percent body fat and less subcutaneous fat on their arms and legs. There were no sex differences in measures of subcutaneous fat on the trunk or in estimates of total body fat. Chest and abdominal circumferences were the measurements most highly correlated with total and percent body fat in the men. In the women, abdominal circumference and subscapular skinfolds were highly correlated with percent body fat, as were subscapular and midaxillary skinfold with total body fat.

Adipose Tissue↗
PubMed1984

Sibling correlations for cranial measurements from serial radiographs.

Sibling correlations are presented for nine craniofacial measurements from lateral cephalometric radiographs of participants in the Fels Longitudinal Study of Growth and their siblings. Because the data were collected serially, measurements on sibs at the same age can be compared at one-year intervals. Sibling correlations are generally lowest during the first year of life and highest as adulthood is approached, but no interpretable pattern is established during the intervening years. Most of the correlations are significantly greater than zero, and many exceed 0.5, the value expected for a completely heritable polygenic trait. This suggests that common sibling environment contributes to sibling resemblance for craniofacial dimensions in our sample.

Adolescent↗
PubMed1983

Longitudinal trends in subcutaneous fat thickness during adolescence.

Longitudinal principal components (LPC) analysis is used to summarize adolescent trends in subcutaneous fat thickness at three sites (biceps, suprailiac, and abdominal). For each site, component 1 (C1) represents fatness level, and component 2 (C2) represents an increase followed by a decrease (fat wave) in fatness. Components 3-5 (retained for girls only) represent more complicated patterns of change (multiple increases and decreases). Correlations among scores for C1 for each site and among scores for C2 for each site indicate a high correspondence of fatness level and the magnitude of the fat wave. Associations between components and other indicators of maturity are apparent, indicating that serial fat patterns are controlled to some degree by influences affecting other pubescent events. Continuity between childhood fatness levels and adolescent patterns of fatness are relatively weak. Continuity between adolescent and adulthood fatness is somewhat greater.

Adipose Tissue↗
PubMed1983

Developmental changes in head-circumference and mental-performance growth rates: a test of Epstein's phrenoblysis hypothesis.

Epstein's phrenoblysis hypothesis states that brain growth and mental growth occur in correlated spurts at 3-10 months and 2-4, 6-8, 10-12 or 13, and 14-16 or 17 years of age. The present study was the first to test statistically such spurts in head-circumference and mental-age growth rates and to assess any correspondence in individual differences between spurts in the two variables in a single sample of children measured serially between 2.5 and 17 years of age. While the statistically significant spurts observed in each variable did fall within the hypothesized age periods, the chance rate for such theoretical concordance was high and several hypothesized spurts were not supported. Moreover, no relationship existed within individuals between head-circumference and mental-age growth-rate patterns.

Adolescent↗
PubMed1983

Iris pigmentation and AC thresholds.

Data from 160 White children were used to analyze possible associations between iris pigmentation and AC pure-tone thresholds. Iris pigmentation was graded from iris color using glass models of eyes, and AC thresholds were obtained under carefully controlled conditions. Analyses of variance using two groupings of iris color grades showed no evidence of an association between iris color grade and AC thresholds. Furthermore, inspection of arrays of the actual glass eye models, in conjunction with the order of mean thresholds at each test frequency, did not indicate the presence of an association between iris color grades and thresholds. It was concluded that while iris pigmentation may be related to some aspects of hearing ability, it does not appear to be related to AC thresholds in children.

Adolescent↗
PubMed1983

Examination effects in audiometric testing of children.

Serial AC threshold data recorded at 6-month intervals in 261 children aged 6 to 18 years have been analyzed for examination effects. After excluding effects of age, linear examination effects are shown by a multivariate analysis of variance for repeated measures and by a regression method. The findings indicate that hearing sensitivity improves with repeated examination. In the present data, the cumulative examination effects for eight examinations at 6-month intervals approximate 3 dB at 0.5, 1, and 2 kHz and 5 dB at 4 and 6 kHz. The effects are larger in the right ear than in the left ear, but there is no significant sex difference. The recorded serial data have been adjusted for the estimated examination effects prior to further analyses.

Adolescent↗