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Biomedical subjects

S Young

Publications and source records attributed to S Young.

At least 325 records · Page 18Linked to original sources
PubMed1977

Significance of positive spike burst in Reye syndrome.

We have previously reported a high incidence of 14-and 6-cps positive spike bursts in comatose patients with Reye syndrome. To further demonstrate this association, positive spike bursts were obtained in three additional cases but only in certain stages during the acute phase of illness. They varied in frequency from 7 to 13 cps, presumably reflecting the degree of slowing of the background EEG activity. A loud noise or other stimuli often precipitated the bursts, particularly when high amplitude delta waves were prominant. We believe that the presence of the positive spike bursts in comatose patients may be of diagnostic significance in Reye syndrome and that an undetermined metabolic or biochemical disturbance may be responsible for their appearance.

Acoustic Stimulation↗
PubMed1977

Dynamic evaluation of the viscoelastic properties of a biomedical polymer (biomer).

This paper deals with the experimental determination of the dynamic constants, storage and loss moduli of a viscoelastic material currently used as membranes in the artificial heart or other types of cardiac bypass pumps. A brief discussion of the viscoelastic theory is given, starting with the relaxation and creep function leading to the determination of the stress-strain relationship in integral equation form. It is shown that when dealing with periodical strain histories, the integral equation form may be reduced to a complex form. The complex moduli are used to describe the stress-strain relationship. The "Hysteresis Loop" method was used in this investigation to experimentally determine the material constants. This method was found to be convenient and direct for the experimental evaluation of the constants. These dynamic constants may then be used in a computer analysis, i.e., finite elements analysis, to determine the stress distribution in the membrane when subjected to loads or deformations.

Acetamides↗
PubMed1976

Intestinal tuberculosis.

Intestinal tuberculosis is a disease with protective clinical manifestations. The radiographic changes in the bowel are similarly varied but often highly suggestive if not characteristic. The key radiologic changes in the bowel, with emphasis on the ileocecal area, are described and the clinical and pathologic features are reviewed.

Aged↗
PubMed1976

Coeliac disease and dermatitis herpetiformis: further studies of their relationship.

Using diagnostic criteria which are currently accepted as most reliable we have found that 19% (9/47) of patients with dermatitis herpetiformis (DH) have no evidence of coeliac disease. The incidence of HL-A8 in the DH patients was 78%, which is considerably greater than that in healthy controls and no different from that reported in coeliac disease. Furthermore, the incidence of HL-A8 was just as much increased in those DH patients without evidence of coeliac disease suggesting that HL-A8 is associated with DH per se--that is, regardless of its association with coeliac disease.

Celiac Disease↗
PubMed1976

The receptive fields of Daphnia ommatidia.

1. The focal length and positions of the principal planes of an isolated Daphnia lens were determined, and the refractive index of the rhabdom was measured. 2. The lens can form an image, but this always lies well behind the rhabdom. This was confirmed by direct observation of images inside a clear-eye mutant Daphnia eye. 3. The rhabdom was shown to be unlikely to function as a waveguide, and a ray optics model is proposed to enable the prediction of ommatidial receptive fields from the lens data. 4. The predicted receptive fields have wide plateaus and steep sides, and there are virtually no totally blind gaps between neighbouring ommatidia.

Animals↗
PubMed1976

Spina bifida, exencephaly, and cranial bleb produced in hamsters by the solanum alkaloid solasodine.

Solasodine, one of the spirosolone structured solanum alkaloids, was gavaged to hamsters at 1184 - 1628 mg/kg once on the 7th or 8th day of gestation. About one-third of all litters from surviving, pregnant dams had one or more deformed offspring. There were 50 abnormals among 727 offspring from 84 dams at sacrifice. Abnormalities included 9 spina bifida, 13 major exencephaly, 25 cranial bleb, 2 hare lip, and 1 anophthalmic types. There were 5 abnormals among 1948 total offspring from 192 control dams. Malformation incidence in controls was 1/10 that in solasodine-gavaged animals. Solasodine gavage also resulted in a large increase in resorptions. Spina bifidas had a protuberance of the skin and other soft tissue in the dorsal mid-line of the lumbosacral region of the fetus. Exencephalics had a prominent dorsocranial defect that fully exposed the brain. Cranial blebs consisted of a soft protuberance of the skin in the mid-line of the interparietal region. The solasodine analogs tomatidine and diosgenin were not teratogenic at dose levels twice as high as the teratogenic dose of solasodine.

Abnormalities, Drug-Induced↗
PubMed1975

Infrared angiography of the cat fundus oculi.

Infrared absorption angiograms of the cat fundus were obtained by regional arterial injection of indocyanine green. There was better resolution of the retinal circulation than that obtained by intravenous injection, but in the choroid only choriocapillaris filling was seen.

Animals↗
PubMed1975

Results of surgery for Crohn's disease in the Glasgow region, 1961-70.

During the period 1961-70, 283 patients in the Glasgow region have been studied with regard to the outcome of 418 surgical procedures performed for Crohn's disease. Resection was followed by an overall recurrence rate of 33 per cent, but in disease confined to the large bowel the rate was 18 per cent. Exploratory operations and bypass procedures were followed by a recurrence rate of 70 per cent. Evidence is provided that recurrence following bypass procedures for small bowel disease and ileocolitis occurs at a later stage than after exploratory operations alone. By the end of the study 77 per cent of patients in this series had required one or more resections.

Crohn Disease↗
PubMed1975

Occurrence of spontaneous hemorrhagic necrosis of the central nervous system in fetal hamsters.

Lesions of hamster fetal neuraxial tissues, characterized by multifocal and coalescent zones of hemorrhage, edema, and necrosis in the cerebral mantle, brainstem, and spinal cord, were observed in experiments designed to test the teratogenicity of potato preparations. Retrospective and prospective data indicated, however, that the potato preparations were not responsible but that the disease occurred spontaneously in the colony and was associated with direct breeding contact of virgin females with certain males. Observations suggest that an infectious agent may be responsible, but no agent was recovered. Immunofluorescence assay of inoculated cultures indicated that reovirus was not present in affected fetal tissues.

Animals↗
PubMed1975

Epidemiological aspects of Crohn's disease in Clydesdale 1961-1970.

A retrospective study of Crohn's disease has been carried out in Clydesdale covering the decade 1961-1970. Three hundred and fifty-seven patients had acceptable evidence of either acute ileitis or of chronic granulomatous bowel disease. Of those fulfilling the criteria for inclusion in the study of chronic disease, 95% had accurate pathological and/or operative documentation of the lesions. Overall, females outnumbered males by 1-6:1 but colonic disease alone tended to affect females, particularly those over the age of 50. The annual incidence of all forms of the chronic disease in both sexes has increased during the decade, but diagnosis of colonic disease alone increased two-fold in the latter half of the study.

Acute Disease↗
PubMed1975

Neurological and pathological effects of second lumbar spondylectomy and spinal column shortening in the dog.

The second lumbar vertebra was surgically removed from 10 dogs, and the shortened vertebral column was stabilized by internal fixation with two types of plastic plates. Shortening of the spinal column was usually not associated with detectable loss of function or neurological deficit. Histological lesions, however, included widely disseminated axonal degeneration, gliosis, and atrophy of spinal nerve roots in the surgical area. The spinal cord adapted to shortening of the vertebral column by becoming intrinsically shorter, rather than be being displaced within the spinal canal.

Adaptation, Physiological↗