PubMed Health⌕ Search

Biomedical subjects

A M Olsen

Publications and source records attributed to A M Olsen.

At least 19 recordsLinked to original sources
PubMed1985

Effects of simulated increases in body weight on the growth of limb bones in hypophysectomized rats.

The purpose of this study was to subject groups of hypophysectomized male and female rats each to a simulated specific 10% increase in body weight, to a maximum of a doubling of body weight, in order to study the effects of quantified, increased, intermittent, compressive forces on limb bone growth. Chronic centrifugation was employed. 21-day-old Sprague-Dawley rats were used. After 60 days of centrifugation, the rats were sacrificed. The humerus, radius, ulna, femur and tibia were removed from each animal, cleared of all soft tissues, and the bone lengths measured on Helios calipers with an accuracy of 1/20 mm. The data were corrected for differences due to individual body weight by dividing bone lengths by the cube root of the body weight of the same animal. Tukey's studentized multiple-range test was performed to identify aggregations (sets) of force groups between which there are significant differences. The data suggest that the simulated increases in body weight, within the range used for this study, enhance bone growth in hypophysectomized female and male rats similarly - hypophysectomy being a condition known to inhibit bone growth.

Animals↗
PubMed1985

Bone mineral content of limb bones of male weanling rats subjected to 30 and 60 days of simulated increases in body weight.

The purpose of this study was to subject groups of male rats each to a specific 10% simulated increase in body weight, ranging from 1.1 to 2.0 g. Constant centrifugation was employed. After 30 and 60 days, rats were sacrificed and perfused with 10% BNF. The humerus, radius, ulna, femur, and tibia were removed, cleared of all soft tissues, weighed, decalcified with EDTA, and reweighed. Bone mineral content (BMC) was determined using the formula: [(Wu - Wd) divided by Wu] X 100. Tukey's multiple range test was used. The data suggest that male weanling rats subjected to simulated increases in body weight, within the range used in this study, undergo enhanced BMC, a bimodal curve describing the relationship between BMC and simulated increases in body weight.

Animals↗
PubMed1985

Effects of simulated increases in body weight from birth on the growth of limb bones in rats.

The purpose of this study was to subject groups of newborn male and female Sprague-Dawley rats each to a specific 10% simulated increase in body weight, to a maximum of a doubling of body weight, to study the effects of quantified, increased, intermittent, compressive forces on limb bone growth. Chronic centrifugation was employed. After 90 days of centrifugation the rats were sacrificed. The humerus, radius, ulna, femur, and tibia were removed from each animal, cleared of all soft tissues, measured and weighed. Tukey's Studentized multiple range test was performed to identify aggregations (sets) of force groups between which there are significant differences. The data suggest that newborn male and female rats subjected to simulated increases in body weight, within the range used for this study, undergo enhanced general body growth and limb bone growth.

Animals↗
PubMed1984

The effects of simulated increases in body weight for 30 and 60 days on bone robusticity of limb bones in rats.

The purpose of this study was to subject groups of weanling male rats each to a specific 10% simulated increase in body weight, ranging from 1.1G-2.0G, using constant centrifugation. (In this paper, "G" is the acceleration due to gravity.) After 30 and 60 days, rats were killed and perfused with 10% buffered neutral formalin (B.N.F.). The humerus, radius, ulna, femur, and tibia were removed, cleared of all soft tissues, weighed, and the total length measured. Bone robusticity was calculated using the ponderal index: bone length/3 square root bone weight. Tukey's Multiple Range Test was used. The data suggest that the specific limb bone, G, and duration of centrifugation are each factors in the response of limb bones to simulated increases in body weight.

Animals↗
PubMed1984

The effects of simulated increases in body weight for 60 days on robusticity and mineral content of limb bones of hypophysectomized rats.

The purpose of this investigation was to subject separate male and female groups of weanling hypophysectomized rats each to a specific 10% simulated increase in body weight using constant centrifugation, ranging from 1.1G to 2.0G, to study changes in bone robusticity and bone mineral content. (In this paper, "G" is the acceleration due to gravity.) After 60 days of centrifugation at 24 rpm, the rats were killed and the humerus, radius, ulna, femur, and tibia were removed, cleared of soft tissues, weighed, measured, decalcified with EDTA, and reweighed. Bone robusticity was determined using the ponderal index: P.I. = bone length divided by 3 square root bone weight; and bone mineral content (BMC) was determined using the formula: BMC = [(Wu - Wd) divided by Wu] X 100. Tukey's Studentized Multiple Range T Test was used. The data suggest that, for both male and female hypophysectomized rats, bone robusticity is decreased with simulated increases in body weight; also, for males, a bimodal curve describing the relationship between BMC and simulated increases in body weight is suggested.

Animals↗
PubMed1984

The effects of simulated increases in body weight from birth on bone robusticity of limb bones of rats.

Groups of newborn rats were each subjected to a specific 10% simulated increase in body weight, ranging from 1.1G to 2.0G, to study changes in bone robusticity. (In this paper, "G" is the acceleration due to gravity.) Constant centrifugation was used. At 90 days of age, the rats were killed and the humerus, radius, ulna, femur, and tibia were removed, weighed, and measured. Bone robusticity was calculated using the ponderal index: bone length/3 square root bone weight. Tukey's Multiple Range Test was used. The data suggest that, for both males and females, bone robusticity is increased with simulated increases in body weight.

Animals↗
PubMed1984

The effects of quantified amounts of increased intermittent compressive forces for 30 and 60 days on the growth of limb bones in the rat.

The purpose of this study was to subject groups of rats each to a specific 10% increase in body weight, to a maximum of a doubling of body weight, to study the effects of quantified, increased, intermittent, compressive forces on limb bone growth. Chronic centrifugation was employed. 21-day-old male Sprague-Dawley rats were used. After 30 and 60 days of centrifugation, the rats were killed. The humerus, radius, ulna, femur, and tibia were removed from each animal, cleared of all soft tissues, measured and weighed. The data were corrected for differences due to individual body weight by dividing bone lengths by the cube root of the body weight of the same animal. Tukey's 'Studentized' Multiple Range Test was performed to identify aggregations (sets) of force groups between which there are significant differences. The data suggest that the value of g, together with the amount of time spent at centrifugation, are both significant factors in the effects of increased intermittent, compressive forces, produced by simulated increases in body weight, on limb bone growth.

Animals↗