Search PubMed⌕ Search

Biomedical subjects

J R Wilson

Publications and source records attributed to J R Wilson.

At least 289 records · Page 16Linked to original sources
PubMed1975

Behavioral and morphological evidence for binocular competition in the postnatal development of the dog's visual system.

Two normally-reared dogs and five dogs reared with monocular eyelid closure were studied. The two normal dogs and three of the deprived dogs were tested with a perimetry technique for the extent of behavioral visual field, and all of the dogs were studied histologically to determine the size of cell somata in the lateral geniculate nucleus. Behaviorally, the normal dogs saw with each eye approximately from 120 degrees ipsilateral to 30 degrees contralateral. The deprived dogs had a normal field of view for the non-deprived eye, but with the deprived eye they saw only in the monocular segment (i.e., approximately 120 degrees to 30 degrees ipsilateral). Histologically, geniculate cells in the monocular segment of deprived dogs were of normal size. In the deprived laminae of the binocular segment, however, cells averaged about two-thirds normal size, and in non-deprived laminae of this segment, neurons were hypertrophied. The hypertrophy was greater for cells in lamina A (40%) than for those in lamina A1 (17%). These data indicate that in monocularly deprived dogs, the monocular segment of the visual system develops normally, but the binocular segment does not. Therefore, we conclude that binocular competition operates in the developing dog's visual system much as it does in the cat's.

Age Factors↗
PubMed1975

Technique for chronic electrode or cannula implantation in decorticate animals.

A surgical technique is described which enables chronic recording of electrophysiological activity and chemical or electrical stimulation in the decorticated animal. This procedure circumvents the problems of inadequate electrode/cannula patency and of the short-term debilitating consequences of cortical ablation. These features make it possible to analyze the relationships between neuroelectrophysiology, behavior and the central mechanisms underlying the restitution of function following brain damage. The procedure appears to be suitable for a wide range of mature laboratory animals and offers several advantages over the few techniques currently available.

Animals↗
PubMed1975

Cognitive abilities: use of family data as a control to assess sex and age differences in two ethnic groups.

Four cognitive factors were extracted from test data obtained on 997 families (3,268 individuals) in Hawaii. Factor loading profiles for the two largest ethnic groups (Caucasians and Japanese) are nearly identical, as are profiles for three different age groups. Age curves are presented for factor scores and for four specific cognitive tests. The younger respondents on the age curves are biological offspring of older respondents represented on the same curves, facilitating an unusual control for between-family variance. When the data were stratified by ethnicity, differential rates of cognitive development were indicated.

Adolescent↗
PubMed1974

Near identity of cognitive structure in two ethnic groups.

As part of a large-scale family study in Hawaii, Americans of either Japanese or European ancestry were administered a battery of 15 cognitive tests. Principal component analyses (varimax rotations) yielded the same four major cognitive factors for each of the two ethnic groups, and these factors are defined by strikingly similar factor loadings.

Asian People↗
PubMed1973

Trephine lung biopsy.

Forty-five percutaneous trephine lung biopsies using the Steel apparatus were performed on 38 patients. Tissue was obtained on 42 occasions (94%) leading to histological or culture diagnosis in 33 patients (87%). Pneumothoraces (12 patients), bleeding into the airways or pleural space (4 patients), and tumour seeding along the needle track (1 patient) occurred in 38% of biopsy attempts (45% of patients). In contrast to the Vim-Silverman technique, the Steel trephine appears to produce a higher tissue yield and superior specimens for histological study. Trephine lung biopsy is comparable to open lung biopsy in providing positive diagnoses. With anticipation and expeditious management of complications, trephine lung biopsy is both safe and useful in the diagnosis of pulmonary disease.

Adenocarcinoma↗