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Biomedical subjects

B S Gupta

Publications and source records attributed to B S Gupta.

At least 37 records · Page 2Linked to original sources
PubMed1982

Enzymatic removal of formalin-fixed tissues from polyester arteries, and its effect on physical properties of fibers.

A method is presented that can be utilized for the removal of formalin-fixed tissues from arterial grafts without affecting fiber material properties. Such a method could prove highly useful for studying the changes in the structure and properties of graft fiber as functions of important clinical variables. Information on what actually happens to the arterial graft material in situ with passage of time is greatly lacking in the current graft literature. The method proposed involves treatment of the formalin-fixed fiber-tissue complex with an enzymatic preparation containing enzymes derived from the porcine pancreas (pancreatin) in solution with tris(hydroxymethyl) aminomethane buffer at pH 7.6. Studies with two different grafts--a Microknit Dacron Bifurcation from a clinical patient 10 1/4 years after implantation and stored in formalin for 11 months, and a Sauvage Filamentous Velour of Dacron from an animal 24 h after implantation and stored in formalin for nine months--showed that the treatment was highly effective in completely removing the tissues at concentrations of pancreatin as low as 2.5%. The same treatment given to the virgin yarns of grafts revealed no significant effects on tensile, dimensional, and morphological properties.

Animals↗
PubMed1978

The effects of dextroamphetamine on kinesthetic figural aftereffects.

The effect of dextroamphetamine, primarily a central stimulant, on kinesthetic figural aftereffects (KFAEs) was examined. The subjects were selected after preliminary testing with the Eysenck Personality Inventory and were classified into three groups: extraverts, ambiverts, and introverts. d-Amphetamine was used at three dose levels and a control group was included for purposes of comparison. The 3 X 4 randomized block design was replicated ten times. KFAEs were measured under two sets of conditions, i.e., before and after the induction experience. The results support the following conclusions: (1) neither personality grouping nor drug treatment during preinduction trials significantly affected KFAE; (2) both types of variables were, however, significantly related to behavior during the postinduction trials; (3) the extraverted subjects showed larger KFAEs than ambiverted and introverted subjects under placebo condition; (4) the extent of KFAE was reduced in extraverted and enhanced in introverted subjects under the influence of the drug; (5) there were significant interactions between the drug treatments and personality variables in effects on KFAE.

Adolescent↗
PubMed1978

Impulsivity/sociability and reinforcement in verbal operant conditioning.

The present investigation was designed to study the relationship between impulsivity/sociability and modes of reinforcement in verbal operant conditioning. Two 2x3 randomized block designs, one each for impulsivity and sociability, were replicated ten times. One hundred and twenty undergraduate female students (60 for impulsivity and 60 for sociability) were individually subjected to Taffel's verbal conditioning procedure. When the conditioning scores of high and low scorers on the impulsivity and sociability scales were compared, it was found that under rewarding conditions ('good' and 'buzzer' in respect of sociability and 'good' in respect of impulsivity) the high scorers' score and under punishing conditions ('electric shock') the low scorers' score was the higher of the two. The study also revealed that the high scorers (on the impulsivity scale) conditioned more under rewarding conditions while the low scorers (both on the impulsivity and sociability scales) conditioned more under punishing ones.

Adolescent↗
PubMed1976

Extraversion and reinforcement in verbal operant conditioning.

The present investigation was designed to study the relationship between extraversion and modes of reinforcement in verbal operant conditioning. A 4 X 3 randomized block design was replicated ten times. Eighty graduate and post-graduate male students were individually subjected to the standard Taffel conditioning procedure. When the numbers of conditioned responses produced by introverts and extraverts were compared, it was found that: (1) under negative reinforcement ('bad' and electric shock), with both the female and male experimenters, and under positive reinforcement ('good') with the male experimenter, the introverts' score was the higher of the two; (2) under positive reinforcement ('good') with the female experimenter, the extraverts' score was higher than that of the introverts.

Adult↗