Biomedical subjects
R Segal
Publications and source records attributed to R Segal.
Antibacterial activity of Artemisia herba-alba.
The antibacterial activity of Artemisia herba-alba was investigated. Only its essential oil was active against some Gram-positive and Gram-negative bacteria. The essential oil was fractionated by column chromatography, and these fractions were tested for antibacterial activity. The principal component of the most active fraction was santolina alcohol.
Pentothal protection for delay cerebral revascularization.
Thiopentone (20 mg/kg/bolus and 20 mg/kg/three hours) was effective in preventing infarction in five dogs with six hours of middle cerebral occlusion. Nine control animals sustained massive to large infarctions. Utilizing this regime therapeutic blood levels were rapidly attained for over 12 hours without side effects. From the experimental and human experience with focal cerebral ischaemia, there appears to be a finite grace period in which cerebral revascularization can be undertaken. In canine and primate models this time has been about five hours, following which the infarction process may not be reversible (Sundt et al. 1977, Laha et al. 1978). Seeking to prolong this grace period, thiopentone was selected as an ideal drug for this purpose, and its effect on the revascularized canine middle cerebral distribution was evaluated at six hours following embolectomy.
Experience-seeking characteristics of methadone clients.
Explore the source record for details and available documents.
Peroxide removal from non-ionic surfactants.
Explore the source record for details and available documents.
Leucocyte migration inhibition in Behçet's disease.
The leucocyte migration inhibition (LIF) was investigated in 16 patients with Behçet's disease, 5 while in the active stage of the process, 3 both during relapse and remission, and 8 during remission of symptoms. In all patients skin tests with various antigens and with a needle prick and physiological saline were simultaneously performed. The results indicate a strong correlation between the activity of the disease, skin reactivity and the reactivity of LIF.
Cardiovascular response to pulsatile pressure applied to ventrolateral medulla.
Explore the source record for details and available documents.
The susceptibility of cholesterol-depleted erythrocytes to saponin and sapogenin hemolysis.
The assumption that complex formation between erythrocyte membrane cholesterol and saponins or sapogenins is the cause for their hemolytic activity, was tested by measuring the susceptibility of cholesterol-depleted erythrocytes towards these hemolysins. For some of the hemolysins cholesterol depletion caused inhibition of hemolysis, for others an augmentation. The results suggest that cholesterol does not serve as a specific binding site for these hemolysins.
Solasodine stability under conditions of saponin hydrolysis.
The extent of formation of solasodiene from solasodine upon treatment with hydrochloric acid under various conditions was determined. The diene formed was assayed by using the characteristic extinction at 236 nm. Diene formation was effected by the acid concentration and the boiling point of the solvent used. Optimal conditions for the hydrolysis of solasodine glycosides are suggested.
Hemolytic properties of synthetic glycosides.
Cholesteryl alpha-L-rhamnopyranoside, tigogenyl alpha-L-rhamnopyranoside, tigogenyl beta-D-fucopyranoside, smilagenyl beta-D-fucopyranoside, cholesteryl beta-maltoside, tigogenyl beta-maltoside, and smilagenyl beta-maltoside were synthesized and characterized. The rhamnosides and fucosides, as well as some other steroid monoglycosides, proved to be extremely insoluble in water. The concentration giving 50% hemolysis, H50, was of the same order of magnitude for all synthetic glycosides. Ghost cells collected from blood hemolyzed by smilagenyl maltoside and tigogenyl maltoside had appreciable amounts of absorbed aglycones. All results are in accordance with previous investigations on the mechanism of saponin and sapogenin hemolysis.
A facile method for detection of the genuine sapogenin from a saponin extract.
Explore the source record for details and available documents.
Spasticity phenomena caused by N-substituted phenylalanine.
Explore the source record for details and available documents.
Institutional services for the mentally retarded: a challenge to the community.
Explore the source record for details and available documents.
The protective action of glycyrrhizin against saponin toxicity.
Explore the source record for details and available documents.
The stability of vitamin A acetate in aqueous cetomacrogol solutions: a spectroscopic study.
Explore the source record for details and available documents.
Deployment--a six year perspective.
Explore the source record for details and available documents.
Trends in services for the aged mentally retarded.
Explore the source record for details and available documents.
Failure of acetylmethadol in treatment of narcotic addicts due to nonpharmacologic factors.
Acetylmethadol, a new narcotic substitute, has a longer duration of action than methadone. Seventeen subjects, former heroin users currently under methadone treatment, entered a study of the toxicity and efficacy of this drug. Only nine subjects completed the assessment phase of the study and began the acetylmethadol phase, and only one completed the 8-week study phase. Hence, no conclusions can be drawn about acetylmethadol's efficacy. The high attrition rate was unrelated to pharmacologic factors; the subjects were concerned that if this drug was effective there would be no methadone to take home and hence no opportunity to trade, sell or "play with" (that is, combine with other drugs) the latter. This study emphasizes the difficulty in determining the efficacy of specific drug treatments for opiate-dependent patients.