PubMed Health⌕ Search

Biomedical subjects

B Weaver

Publications and source records attributed to B Weaver.

12 recordsLinked to original sources
PubMed1992

Effect of zinc sulfate and acetylcysteine on experimental gastric ulcer: in vitro study.

A small ulcer produced in vitro by monopolar electrocoagulation on endoscopically obtained human antral biopsies and incubated in Trowel T-8 medium at 37 degrees C for 8 h has many histologic features of chronic gastric ulcer in man. Zinc sulfate and acetylcysteine in low concentrations had a significant healing effect in this ulcer model. Since the beneficial effect of zinc sulfate and acetylcysteine was counteracted by N-ethylmaleimide, a known blocker of sulfhydryl compounds, the beneficial effect of these two compounds probably was mediated through sulfhydryl compounds. Using special stain, N-(4-aminophenyl)maleimide, the sulfhydryl groups were localized in the epithelial cells of the surface layer and gastric glands.

Acetylcysteine↗
PubMed1991

Inhibitory mechanisms of attention in identification and localization tasks: time course and disruption.

It has been proposed that 1 component of the mechanism of visual selective attention is active inhibition of distracting information. A series of studies examines the time course of inhibition and the possible interfering effects of other task demands. Results demonstrate that inhibition can last at least 7 s after selection processes and that it is unaffected by predictable, unrelated intervening events. However, intervening events that are less predictable, or are the same as the inhibited stimulus, disrupt inhibition. Such results motivate a reconsideration of the previous view of distractor inhibition as a transient, fragile phenomenon.

Adolescent↗
PubMed1991

Object-centred inhibition of return of visual attention.

Our response to visual events can be delayed at positions we have recently examined attentively. Such inhibition could organize visual search through static scenes by suppressing those loci already searched, but this mechanism would fail in moving scenes as objects' locations then change during search. We cued attention to a moving object and found subsequent inhibition at the locus the object later occupied. This implies that previously examined objects are suppressed. Such object-centred inhibition would be highly adaptive, but would require a sophisticated neural implementation for a mechanism held to be sub-cortical.

Adult↗
PubMed1991

Inhibitory mechanisms of attention: locus, stability, and relationship with distractor interference effects.

This paper examines three properties of attentional inhibition mechanisms. First, previous research has suggested that the inhibitory mechanism of selective attention has a central locus between perception and action. We attempt to confirm the locus of this inhibition. Second, the processing of an unattended stimulus has been observed via the effects of the stimulus on a concurrent target (interference), and on a subsequent target (negative priming). The former effect demonstrates that distractors interfere with the processing of the target, and the latter negative priming effect implies that distractors are inhibited during selection. We demonstrate that these two measures of unattended processing can be dissociated. Third, we reveal that inhibition appears to be a stable mechanism of selection, in that effects do not decline after a large number of experimental trials.

Attention↗
PubMed1983

Inexpensive double-antibody fluoroimmunoassay for aminoglycoside antibiotics, phenytoin, and theophylline in serum.

We describe simple, clinically useful double-antibody fluoroimmunoassays for amikacin, gentamicin, tobramycin, theophylline, and phenytoin. The fluorescent tracers were prepared by conjugation to fluorescein isothiocyanate; the antisera were raised in rabbits. A simple filter fluorometer and disposable culture tubes are used. The tracer, sample, and first and second antibodies are combined and incubated at room temperature for 30 min. A precipitation-acceleration buffer is added, the samples are centrifuged, and the fluorescence of the supernate is measured directly in the assay tube without decantation. Interferences, usually negligible, can be corrected for by use of a sample blank. Results compare favorably in performance with various commercially available RIA and enzyme immunoassays.

Aminoglycosides↗