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Biomedical subjects

P Ross

Publications and source records attributed to P Ross.

At least 127 records · Page 7Linked to original sources
PubMed1983

Tissue culture of guinea-pig gall-bladder epithelium.

Tissue culture of gall-bladder was attempted in the following media: Dulbecco, Eagle's minimum essential medium, NCTC 135, medium 199 and Ham's F12. Growth occurred in all of them for up to 2 weeks assessed by light microscopy. No enhancement of growth was induced by collagenase trypsin insulin or hydrocortisone. Scanning electron microscopy confirmed that new cells colonised the free surface of the explant. Transmission electron microscopy showed good preservation of the original tall epithelial cells for the period of study. The new migrating cells were flatter, but retained the morphological features of the columnar cells. Secretory granules were absent after 1 day in culture but increased amounts of glycogen and lipid began to appear in the epithelium.

Animals↗
PubMed1983

Phonological processing during silent reading in aphasic patients.

In a task involving the detection of a predesignated letter during the silent reading of a series of passages, left-brain-damaged aphasic patients and right-brain-damaged patients showed patterns of performance consistent with those of normal individuals. Both of the brain-damaged groups were more likely to detect letters when they were pronounced in a typical way (e.g., g in "ago") than in an atypical way (e.g., g in "through"), suggesting the use of phonological recoding during silent reading. In addition, both of these groups were more likely to detect letters when they occurred in content than in function words, suggesting a differential processing of these word types. Possible differences in the strategies predominantly relied on for phonological recoding and for the differential processing of content and function words by different groups of patients are discussed.

Aphasia↗
PubMed1983

Changes in visual field advantage for facial recognition: the development of a general processing strategy.

During the recognition of tachistoscopically presented faces, subjects initially showing a LVF advantage decrease and then increase that advantage; subjects with an initial RVF advantage shift to a LVFA. We examined whether these shifts result from increasing familiarity with specific faces or rather from the development of a more general facial processing strategy. This was accomplished by changing the set of faces presented for recognition during testing. Across trials, the VFA of initially RVF advantaged subjects showed a linear trend, that of LVF advantaged S's a quadratic trend. These trends don't differ from those of subjects tested with one set of faces, suggesting that subjects were learning a general strategy for facial recognition.

Discrimination Learning↗
PubMed1983

Determinants of bone mass in postmenopausal women.

Eighty white women, mean age 52 years, within one to six years postmenopausal, were studied to examine the relationship of various factors to bone mass. Forty-four of the women had annual measurements of bone mass, so that the rate of bone loss could be determined. Bone mass was measured by total body neutron activation analysis and photon absorptiometry of the distal radius (total body calcium [TBCa] and bone mineral content [BMC], respectively). Breast-feeding and pregnancy were noted to be associated with higher bone mass; those with lower BMC and/or TBCa tended to have higher serum alkaline phosphatase levels, lower testosterone levels, and more years since the cessation of menses. The rate of bone loss from the radius was greater in those with higher parathyroid hormone levels; those with reduced dietary intake of calcium and lower 25-hydroxyvitamin D levels had a greater rate of loss of TBCa.

Bone and Bones↗
PubMed1982

Changes in hemispheric advantage in processing facial information with increasing stimulus familiarization.

Thirty-nine female subjects were given a task involving recognition of initially unfamiliar faces which were tachistoscopically presented to one or the other visual field. In support of a hypothesized dual mode of right hemisphere function, those subjects who showed an initial left visual field advantage exhibited a diminution and then an increase in this advantage with increasing familiarity with the faces. This resulted in a significant quadratic component in their magnitude of hemispheric advantage. In contrast, those individuals who showed an initial right visual field advantage had neither a significant linear nor quadratic component in the magnitude of their advantage. Significant correlations between number of errors and magnitude of hemispheric advantage, independent of direction, were also found. The results are discussed in terms of possible optimal sequences and timing of shifts in information processing strategies and associated hemispheric advantages.

Adolescent↗
PubMed1982

Rate of bone loss in postmenopausal and osteoporotic women.

Regional and total bone mass were determined in three groups of women by photon absorptiometry of the distal radius [bone mineral content BMC)] and total body neutron activation analysis [total body calcium (TBCa)], respectively. There were three groups of patients: group A, osteoporotic women treated with a variety of pharmacologic agents; group B, osteoporotic women (controls) taking only calcium supplements; and group C, normal postmenopausal women. The mean TBCa and BMC were considerably higher in the postmenopausal women than in the osteoporotic women. The rate of change of bone mass in group C was -0.45%/yr and -0.9%/yr for the total skeleton and radius, respectively. Group B had no significant rate of loss, whereas group A demonstrated a significant increase in TBCa of 0.75%/yr with no change in the BMC of the radius. There were no significant between-subject correlations for the slopes (rates of change) of the two bone mineral measurements.

Bone Resorption↗
PubMed1981

The binding of [3H]oestradiol-receptor complexes to calf uterine chromatin.

Various aspects of the interaction of oestrogen-receptor complexes with calf uterine chromatin covalently coupled to cellulose were analysed. Partially purified [3H]oestradiol-receptor complexes were bound to intact, or partially deproteinized, chromatin resins. Proteins were removed from the chromatin-cellulose resins by extraction with high molarities of salt, including NaCl/urea, guanidine hydrochloride and guanidine thiocyanate. After extensive washing to remove the salt, [3H]oestradiol-receptor-complex solutions were added to the resins and the degree of binding was determined. The extent of [3H]oestradiol-receptor-complex binding to chromatin was enhanced by extraction of chromosomal proteins. By varying the molarity of the salt, and consequently the extent of protein removal, it was possible to resolve [3H]oestradiol-receptor-complex binding to guanidine thiocyanate-extracted chromatin into two components. Similarly, [3H]oestradiol-receptor-complex binding to guanidine hydrochloride-treated chromatin included three regions of enhanced binding capacity. The [3H]oestradiol-receptor-chromatin interaction was saturable with respect to both intact and salt-extracted resins. Thus uterine chromatin may contain three or more specific classes of acceptors for the oestrogen-receptor complex.

Animals↗
PubMed1981

Epidemic polyarthritis in northeastern Australia, 1978-1979.

In a study of epidemic polyarthritis in central and northern Queensland, clinical disease was observed most frequently in urban-dwelling adult females. Clinical and subclinical infections were detected year round, although the majority of clinical infections occurred between the months of January and June. In the communities studied, there were approximately 50 subclinical infections for each clinical infection. There was no detectable association between any HLA-A or HLA-B phenotypes and epidemic polyarthritis.

Adolescent↗
PubMed1981

Computerized tomographic evaluation of early idiopathic midline granuloma.

Idiopathic midline granuloma (IMG) is a rare, slowly progressive inflammatory process producing localized destruction of the nasal mucosa, septum, paranasal sinuses, and palate, often associated with erosion through central facial tissue and bone. We review some of the salient features of IMG and present the first reported CT demonstration of this disease.

Child↗
PubMed1981

Individual differences in cerebral asymmetries for facial recognition.

In the recognition of tachistoscopically presented unmasked upright faces, some individuals showed a RVF, i.e., left-hemisphere advantage while others showed a LVF, i.e., right-hemisphere advantage. Individuals with a LVF advantage in recognition of these faces showed an increase in errors when the faces were inverted whereas those with a RVF advantage did not. Individuals with a RVF advantage in recognition of the unmasked upright faces showed a greater increase in errors when individual features of the faces were masked than those with a LVF advantage. These results confirmed the view that individuals with a RVF advantage in facial recognition were using an analytic strategy in processing the stimuli whereas those with a LVF advantage were using a holistic strategy.

Adult↗
PubMed1981

The effect of dietary calcium supplementation on serum calcium, phosphorus, and alkaline phosphatase concentrations in a rural black population.

In a rural community, where low calcium intakes and a high prevalence of hypocalcemia elevated alkaline phosphatase values and hypocalciuria had previously been documented, two groups of 30 black school children were supplemented with calcium (500 mg/day) or a placebo for a period of 3 months. No change in serum calcium or alkaline phosphatase values occurred in the placebo group, while a significant rise in mean serum calcium and fall in mean alkaline phosphatase concentrations was found in the calcium-supplemented group over the 3-month trial. No difference in growth velocities in the two groups of children was noted over the period. These results suggest that the prevalence of biochemical abnormalities in the rural population is related to a low dietary calcium intake which can be corrected by a supplement of oral calcium only.

Alkaline Phosphatase↗
PubMed1980

Nontropical chyluria associated with pelvic lipomatosis.

A patient never exposed to filarial parasites presented with intermittent chyluria and was found to have coincidental pelvic lipomatosis. The pathophysiology of chyluria and pelvic lipomatosis are reviewed and their possible relationship in the present case is discussed.

Aged↗
PubMed1980

The "bull's-eye" falciform ligament: a sonographic finding of portal hypertension.

The umbilical vein may dilate as a collateral in portal venous hypertension and become visible within the echodense fat of the falciform ligament. The resulting "bull's-eye" appearance was visible in 5/47 (11%) of patients with cirrhosis secondary to alcohol abuse. It was not visualized in any patients with cholelithiasis who had no evidence of cirrhosis. When demonstrated by ultrasound, this finding should suggest portal venous hypertension.

Adult↗