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Biomedical subjects

W R Anderson

Publications and source records attributed to W R Anderson.

At least 109 records · Page 6Linked to original sources
PubMed1979

The effect of transection of the accessory ligaments on reproduction in the rabbit.

The mesotubarium superius (MTS) and uterovarian ligament (UOL) contain smooth muscle, are mechanically active, and have been implicated in ovum transport in a number of species. To assess the reproductive importance of these ligaments, they were unilaterally transected in 27 rabbits and the effects on reproduction determined. Reproductive function was characterized in terms of the numbers of corpora lutea, uterine implants, and normal conceptuses resulting from breeding with fertile bucks. Fertility was defined by the proportion of ovulating follicles resulting in implantation and normal conceptuses. Grouped and paired sample analyses of these data showed no differences between the experimental and control sides of the reproductive tracts of animals in which the UOL, MTS, or both were transected. The structural integrity of these ligaments is thus not necessary for normal conception and fertility in the rabbit.

Animals↗
PubMed1978

Empirical model of intracranial pressure and head motion resulting from a vibrating seated rhesus.

A series of experiments was designed to measure the head X and Z accelerations and the intracranial pressure in the unrestrained head of a rhesus monkey. The subject was exposed to a continuum of vibration frequencies from 2 to 35 Hz and peak acceleration amplitudes of 5, 10, 20, and 40 m/s2. The resulting data was used to build a frequency response model relating the head accelerations and pressures to the torso acceleration. The head-to-torso relationships, based upon a single subject, were both repeatable and invariant for torso acceleration amplitudes of 10, 20, and 40 m/s2. At frequencies above the 10Hz, the model strongly suggested the presence of linear system, and the inherent advantages of superposition. The model demonstrates the validity of the experimental method, involving a slow sweep through a range of frequencies, and of the analysis procedures used. More importantly, it promises to be a useful approach to the study of human response to vibration.

Animals↗
PubMed1978

Predictive model of dynamic response of the human head/neck system to -Gx impact acceleration.

This paper describes the mathematical framework, underlying an empirical model, that predicts human head response using only the motion present at vertebra T1. Based on this framework, a model for --Gx impact acceleration was developed from data obtained on six volunteer subjects participating in the NAMRL impact acceleration experiments. Model performance was evaluated by comparing the errors in the predicted head responses with the normal variations observed between the responses of different subjects under identical impact accelerations. Independent sets of data were used for building and testing the model. The results of the evaluation indicate that the model will be useful in subsequent studies of human response to impact acceleration.

Acceleration↗
PubMed1977

Leydig-cell tumor of the testis with gynecomastia and elevated estrogen levels.

A normally-virilized 24-year-old white man who had gynecomastia was found to have a Leydig-cell tumor of the testis, without demonstrable metastases. Hormonal evaluation revealed negative serum and urine tests for human chorionic gonadotropin, and normal steroid excretion. Prior to orchiectomy, serum estradiol was elevated and serum testosterone depressed; postoperatively these values reverted to normal. Attempts to quantitative the estradiol content of the tumor failed to show a significant increase over normal testicular tissue, however. Histologically, the tumor showed classic Reinke crystalloids, the nature of which remains undefined. Electron-microscopic studies showed these crystals to have a regular hexagonal pattern.

Adult↗
PubMed1976

Radiation-induced renal disease. A clinicopathologic study.

Radiation injury to the renal parenchyma is an unusual cause of renal insufficiency. Light, immunofluorescence and electron microscopic studies were performed on the renal tissue from two patients in whom renal insufficiency developed within a year after they received abdominal irradiation. The glomerular lesion in both patients was similar. Mild endothelial cell swelling and basement membrane splitting were noted consistently on light microscopy. The electron microscopic examination revealed marked subendothelial expansion with electron-lucent material associated with deposition of basement membrane-like material adjacent to the endothelial cells. In some capillary loops, the endothelial cell lining appeared to be completely lost. The pathogenesis of radiation-induced renal injury is still uncertain. It is speculated that local activation of the coagulation system with consequent thrombosis of the renal microvasculature may be extremely important.

Adult↗
PubMed1976

Toxic effects of hydroperoxide injections on rat lung. A light microscopical and ultrastructural study.

Intravenous administration of methyl linoleate hydroperoxide (MLH) uniformly resulted in extensive damage to septal wall components of the rat lung; the severity of these changes paralleled the administered dosage. The target cell of injury appeared to be the capillary endothelial cell. Destructive changes within the plasma membrane suggested that the major toxic effect of MLH was directed against membranous structures. Ultrastructural analysis showed that these effects were more severe in the vitamin E-deficient animals. Secondary changes were characterized by interstitial and alveolar edema, and degenerative changes within alveolar pneumocytes. Reparative proliferation of type 2 pneumocytes first became evident in animals that survived two days. These observations provide an insight into the susceptibility and sequential damage to pulmonary tissue by hydroperoxides and serve as a guide for investigations of the toxic effects of other oxidants on lung.

Animals↗
PubMed1975

Recurrence of idiopathic membranous nephropathy in a renal allograft.

A middle-aged man with idiopathic membranous nephropathy, who developed chronic renal failure, received a cadaver renal allograft. Two months later, massive, persistent proteinuria developed. A biopsy specimen of the allograft showed changes characteristic of membranous nephropathy and identical to those present in the patient's own kidney. The criteria for recurrence of glomerulonephritis in renal allografts are met in this case.

Animals↗