The weight, density and percentage ash weight of the dry, fatfree osseous human skeleton have been examined from 16 weeks of gestation to 100 years of age. Data were drawn from 426 skeletons of American Whites and Negroes of both sexes.Weight increases exponentially in the fetus and continues to increase to early adulthood, most rapidly in the second decade. A decrease appears about the fourth decade and continues gradually. Estimated loss in skeletal weight throughout the adult period is, on the average, 15.6 gm per year. Proportionate contributions of divisions of the skeleton to its total weight change with age.Densities of bones follow the changing weight pattern. Volume and weight increase concomitantly to adulthood, when weight decreases but not volume.Percentage ash weight increases slightly in the total skeleton and in some bones during the fetal period, with no significant trend thereafter, indicating that change in weight of a dry, fat-free bone is accompanied by change in ash weight.Race and sex differences are not evident in the fetal skeleton, but become marked by the second decade of life: Negro skeletons exceed White skeletons and male skeletons exceed female skeletons in mean weight and density and, to a lesser degree, in percentage ash weight.Growth and development of the human skeleton have long been subjects of interest to anatomists, anthropologists and physicians. Yet, surprisingly, there are comparatively few quantitative data regarding such basic considerations as the sequential changes throughout fetal and postnatal life in weight or length of individual bones, in the relationship of the weight of individual bones to that of the whole skeleton, and in the relative proportions of the organic and inorganic components of bone in individuals of different race or sex.Our interest in these problems goes back more than 20 years when we began an extended series of studies on the weight of the skeleton. These studies include (1) estimates of the weight of the skeleton in the adult (Trotter, '54); ( 2 ) an attempt to determine how skeletal weight might be estimated in the living subject (Merz, Trotter and Peterson, '56); ( 3 ) what relationship exists between the weight and the volume of a particular bone (Broman, ANAT. REC., 179: 1-18. Trotter and Peterson, '58; Trotter, Broman and Peterson, '58, '59, '60; Trotter and Peterson, '70a; Trotter, '71); ( 4 ) how much of the weight of the skeleton is attributable to its mineral content (Trotter and Peterson, '55, '62; Trotter, '72, '73); and ( 5 ) to what extent skeletal weight varies in individuals drawn from different race, sex and age groups (Trotter and Peterson, '68, '69, '70b). Since this work has been published in several different journals over an extended period of time, it seems worthwhile to collate and summarize these earlier findings sequentially as related to age, and to present results of additional analyses of these same data.The skeletons had been collected over the last 50, or more, years, and all were obtained from cadav...
The safety and efficacy of influenza vaccination were studied in 32 healthy volunteers and in 62 patients with systemic lupus erythematosus (SLE), rheumatoid arthritis, degenerative joint disease, and other rheumatic diseases. These individuals, none of whom was acutely ill, were examined at the time of immunization and one week, three weeks, and four months later. Flare-ups of rheumatic disease following immunization were infrequent and usually minor. Seroconversion to A/New Jersey/76 developed in 62% to 87% of all individuals and to A/Victoria/75 in 62% to 69%. Antibody responses to A/New Jersey/76 were significantly lower in young patients taking glucocorticoids compared to those not taking glucocorticoids. The antibody responses to A/New Jersey/76 and A/Victoria/75 in patients with SLE were not different from normal responses. Administration of these vaccines was safe in these patients with stable disease and induced antibody responses in most individuals.
To evaluate the risk of relapse in children with epilepsy whose anticonvulsant therapy has been withdrawn after prolonged control, we studied 148 such children for 15 to 23 years or until relapse. Forty-one of the 148 patients (28 per cent) had recurrence of seizures; of these, 35 (85 per cent) had relapses within five years of drug withdrawal. Factors associated with an increased risk of relapse were a long duration of epilepsy before control, neurologic dysfunction, and jacksonian seizures or combinations of seizure types. We found no association between risk of recurrence and age at onset of epilepsy, total number of seizures before control, age at discontinuation of therapy, electroencephalographic abnormalities, or family history of epilepsy. We conclude that children who do not have the additional risk factors noted above have an excellent chance of remaining seizure free after the withdrawal of anticonvulsant drugs.
Carcinomas of the breast from 352 women were assayed for binding of tritiated estradiol by tumor cytosol with dextran--charcoal adsorption, saturation analysis, and two-point Scatchard plots; the level of saturable binding defined a cytosol as positive or negative for estrogen receptor. Valid assays were obtained on specimens as small as 120 mg. Assays of replicate samples of a cytosol were more reproducible than assays of replicate samples of the tumor itself. Occasional disparity of results between a primary mammary carcinoma and its axillary metastases could be related to differences in tumor cellularity. Saturable binding consistent with the presence of estrogen receptor was found in 59% of 305 primary carcinomas and in 57% of 47 metastatic or recurrent carcinomas. There was a significant negative correlation between the patient's age and saturable estrogen binding in the tumor. Serum estradiol levels of less than 250 pg/ml appeared to have a negligible effect on estrogen receptor content. A small subgroup of high-binding carcinomas had high dissociation constants, but the significance of this observation is not clear.
A cross-sectional sample of 151 skulls from Macaca mulatta of known age and similar rearing in U.S. Primate Centers was analyzed to determine age-related "norms" of stages of development and size of teeth. The stages of development from the follicle of a deciduous incisor in the fetus to completion of the root with apex closed of the permanent third molar were related to age. The age range observed for eruption of each tooth was noted and related to its stage of development. The crown of each erupted tooth was found to be completely developed, but growth of its root continued for a longer, indeterminate period. When a deciduous tooth was exfoliated, the crown of the permanent successor was found to be completed and root growth had begun. Measurements of both mesiodistal and faciolingual diameters and of crown length of the teeth in situ and of total length and root length on roentgenograms were examined for sexual dimorphism. The faciolingual diameter of the deciduous mandibular second incisor and of both second molars showed the greatest sexual dimorphism among both diameters of all deciduous teeth. The mesiodistal and faciolingual diameters of the mandibular premolars were found to be the best dimensions in discriminant functions for identifying sex in the absence of permanent canines.
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