PubMed Health⌕ Search

Biomedical subjects

M Oide

Publications and source records attributed to M Oide.

9 recordsLinked to original sources

Combining regression trees and radial basis function networks.

We describe a method for non-parametric regression which combines regression trees with radial basis function networks. The method is similar to that of Kubat, who was first to suggest such a combination, but has some significant improvements. We demonstrate the features of the new method, compare its performance with other methods on DELVE data sets and apply it to a real world problem involving the classification of soybean plants from digital images.

Models, Statistical↗

Effect of alpha-methyldopa on alpha-noradrenergic receptor binding sites in the mouse brain.

alpha-Methyldopa (alpha-MD) was administered intraperitoneally into adult male mice and its effect on alpha 1- and alpha 2-noradrenergic receptor binding sites in the brain was investigated, using [3H]WB-4101 and [3H]clonidine, respectively. A single injection of 50-200 mg/kg alpha-MD abolished the high affinity binding to alpha 2-receptor sites and only the low affinity binding was observed with lower Bmax values. A significant effect of alpha-MD on alpha 1-receptor sites was not detected even after repeated injections (200 mg/kg/day X 3). Pretreatment with fusaric acid or diethyldithiocarbamate (inhibitors of dopamine-beta-hydroxylase) exerted no influence on the actions of alpha-MD on alpha 2-receptor sites, whereas NSD-1055 (an inhibitor of dopa decarboxylase) inhibited the effects of alpha-MD. It is concluded, therefore, that alpha-methyldopamine, a decarboxylated metabolite of alpha-MD, may be responsible for the reducing effect of alpha-MD on alpha 2-receptor sites.

Animals↗

Uptake and metabolism of choline by the embryonic heart of the chick in vitro.

1. The uptake and metabolism of [14C]choline was investigated in isolated hearts from 4- to 14-day-old chick embryos. 2. A high-affinity uptake system of choline was present in hearts from all ages of embryos examined: the Km values were 9-11 muM, while the Vmax values ranged from 5 (14-day ventricles) to 77 (4-day atria) pmol choline/mg protein/min. 3. Hemicholinium-3, metabolic inhibitors, low temperature and low Na+ concentrations reduced the high-affinity uptake process. 4. The accumulated choline was converted mainly into phosphorylcholine in 4-day hearts, while the percentage of conversion into acetylcholine increased in older embryos.

Animals↗

Development of acetylcholine sensitivity of embryonic chick atria in culture.

Atria were isolated from chick embryos of 4--12 days incubation and maintained up to 9 days in culture to examine change in their sensitivity to acetylcholine (ACh). Beating of atria from 4-day embryos was not affected by ACh at the start but was inhibited after a few days of culture. Atria from old embryos which had been sensitive to ACh remained so in culture. Desensitization to ACh was marked in short-term culture of 4-day embryonic atria. Sera and embryo extracts facilitated the appearance of ACh sensitivity. Binding of quinuclidinyl benzilate was observed in ACh-insensitive atria. Cycloheximide, puromycin and actinomycin D prevented the appearance and maintenance of ACh sensitivity in culture, leaving the heartbeat unaffected.

Acetylcholine↗