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Biomedical subjects

R Bauman

Publications and source records attributed to R Bauman.

8 recordsLinked to original sources
PubMed1991

An experimental analysis of the cost of food in a closed economy.

Rats lived in individual chambers in which the only food available was delivered for lever pressing. During Stage I, a fixed number of presses was required for each food pellet. As this fixed ratio of presses per food pellet was increased daily, a rat's daily intake of food was reduced. During Stage II, the cost of a food pellet was increased by replacing each fixed ratio with its interval equivalent. Each interval was a rat's mean time between the first press of a ratio and the delivery of a pellet during Stage I. During Stage II, only two presses were every required for a food pellet: The first press initiated a delay and the second activated the pellet dispenser after that delay elapsed. Food intakes for the series of fixed ratios and a rat's series of delay equivalents were very similar when plotted as a function of delay, but not when plotted as a function of presses per pellet. Consequently, the fixed ratio reduced food intake because larger ratios increased delay to food from the first press of a ratio. Observations and an analysis of interresponse times further revealed that as the fixed ratio increased, and local as well as overall rate of food intake decreased, lever pressing became more stereotyped. Because this increased stereotypy resulted in greatly increased rates of lever pressing, delay to food was minimized, and perhaps more importantly, so too was the reduction of a rat's baseline daily intake.

Animals↗
PubMed1979

Minimizing postinsertion problems: a procedure for removable partial denture placement.

A procedure for removable partial denture placement has been described. This procedure involves correction of pressure spots and overextensions, harmonizing of occlusion, and patient home-care instructions. Use of this procedure does not eliminate the need for postinsertion observations. Postinsertion adjustments, however, may be minimized by careful attention to each step at the placement visit.

Dental Occlusion, Balanced↗
PubMed1977

Computerized cranial tomography. Effect on diagnostic and therapeutic plans.

The effect of computerized cranial tomography (CCT) on physicians' diagnostic and therapeutic plans in 194 patients scanned consecutively during a 17-day period at the Massachusetts General Hospital was studied. Use of CCT substantially decreased the perceived need for other neurodiagnostic tests in this patient population. There was a reduction of a least 41% in radionuclide scans, 52% angiograms, and 73% in pneumoencephalograms compared to the needs projected had CCT not been available. Therapy was altered after 37 scans in 36 patients (19% of those examined): new treatment was begun after 15 scans, previously planned therapy became more precise after 9 scans, treatment was found to be unnecessary after 7 scans, and treatment was abandoned as worthless after 6 scans.

Brain Neoplasms↗
PubMed1975

Oxygen-linked CO2 transport in sheep blood.

We have analyzed oxygen-linked carbamate formation in sheep hemoglobin B by measuring a) the effect of CO2 on oxygen affinity and Bohr effect in red cell suspensions and dilute (1.3 mM Hb4) and concentrated (5 mM Hb4) hemoglobin solutions at 37 degrees C and b) CO2 binding curves of deoxygenated and oxygenated whole blood and hemoglobin solutions, respectively, at the same temperature. In the presence of CO2 both the Bohr effect and oxygen affinity were significantly lower in 1.3-mM Hb4 solutions than in either red cell suspensions or 5-mM Hb4 solutions, while in the absence of CO2 Bohr effect and oxygen affinity did not differ significantly in those preparations. Likewise, the fraction of oxygen-linked carbamate obtained from CO2 binding curves was found to be higher in 1.3-mM Hb4 (0.156 M HbCO2/M HbO2) solutions than in 5-mM Hb4 solutions (0.12 M HbCO2/M HbO2) at pH 7.2. We conclude that hemoglobin concentration affects formation of oxygen-linked carbamate. Total oxygen-linked CO2 in sheep whole blood amounted to 0.18 M CO2/M O2 of which 70% is oxygen-linked carbamate. Assuming a respiratory quotient of 0.85, the contribution of oxygen-linked CO2 to carbon dioxide exchange in sheep blood was computed to be 21%.

Animals↗