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Biomedical subjects

A Shaw

Publications and source records attributed to A Shaw.

At least 289 records · Page 16Linked to original sources
PubMed1976

Responses of cancer patients in the MEM test: not just a function of charge on basic proteins.

It has been reported that lymphocytes from cancer patients give positive responses to PPD, myelin basic protein, tumour basic protein, and certain histone fractions in the MEM test. The underlying mechanisms of the MEM test are poorly understood, but it is widely assumed that it detects immunological sensitization to specific antigenic determinants. The cross-reactivity experienced is interpreted as indicating shared antigenicity. Since all the stimulatory proteins are strongly basic we investigated an alternative explanation that responsiveness is a function of electrical charge by comparing the known stimulatory proteins in the MEM test with two others of similar basicity: lysozyme and cytochrome-C. We obtained highly significant stimulation with PPD, tryptophane peptide of myelin, and tumour basic protein using Mantoux + cancer patients, but found no response to other basic proteins. We failed to confirm the reported activity of histone F2a. Our results indicate that basicity alone is insufficient to elicit response, and strengthens the concept that the MEM test is measuring sensitization to the determinants shared by myelin and tumour basic protein.

Animals↗
PubMed1976

Experience in the development of low haemolysis pumps.

In an attempt to provide a pulsatile pump with a low rate of haemolysis, two pulsatile pumps have been developed. These were compared with commercially available pulsatile and roller pumps. The blood flow and the rate of haemolysis were studied under similar conditions. Our pumps were significantly better than the commercial pumps as far as mechanical damage to the red blood cells was concerned. However, we carried out certain modifications to one of our pumps which resulted in a significant reduction in the amount of haemolysis over its previous performance.

Heart-Lung Machine↗
PubMed1976

Experimental evaluation of mechanical haemolysis with Starr-Edwards, Kay-Shiley and Björk-Shiley valves.

Mechanical cell damage was studied in vitro with three types of prostheses: Starr-Edwards, Kay-Shiley and Björk-Shiley valves. Mechanical cell damage was found to be closely related to the flow characteristics in the prosthesis. Considering valves of similar orifice diameter, Björk-Shiley valves produced the lowest rate of haemolysis. This is due to the improved haemodynamic characteristics of the valve which resulted from the laminar type of flow. With Starr-Edwards valves, smaller sizes produced unacceptably high rates of haemolysis. Increasing the mean forward flow across the valve resulted in a disproportionate rise in the energy loss and the rate of haemolysis when compared with Björk-Shiley valves of similar annulus diameters.

Blood Flow Velocity↗
PubMed1976

A solid state delayed auditory feedback system for speech therapy.

A delayed auditory feedback system has been constructed using solid state integrated circuit components. The construction of the instrument is described and the advantages of such an electronic device over conventional electro-mechanical systems are discussed.

Analog-Digital Conversion↗
PubMed1976

A comprehensive treatment unit for the respiratory distress syndrome in the newborn.

Various systems have been devised to improve the therapy of idiopathic respiratory distress syndrome in newborn infants. This article describes a new ventilator which provides alternating positive and negative pressure ventilation(APNPV) in addition to the more conventional techniques. Safety aspects, technical performance and cleaning procedures are described. A brief summary of the clinical performance of the machine is given.

Electronics, Medical↗
PubMed1975

Mechanical deficiencies in scintillation counters, scanners, and gamma cameras.

After an accident involving a scintillation counter, the machanical integrity of scintillation counters and their stands, rectilinear scanners, and gamma cameras was examined. An alarming proportion of these divices were found to be poorly designed with consequent danger to patients and staff. This class of equipment should be covered by standards incorporated in a comprehensive hospital technical memorandum.

Accident Prevention↗
PubMed1975

Medical equipment hazards--practical experience in a large region.

An investigation has been carried out into the cause of accidents involving patient interfaced medical equipment, in a large region over a period of 3 years. In a high proportion of accidents the cause is faulty design, or poor construction of equipment. However, a considerable number can also be attributed to lack of user appreciation of the hazards involved. A few accidents have been caused by inexperienced personnel attempting to service equipment about which they have little knowledge.

Accidents↗
PubMed1975

Electrical interference in hospitals--practical experience in a large region.

A great deal has been written about electrical interference, yet there is a distinct lack of information for the hospital environment. There are many factors affecting this problem in the clinical context and we report on our own practical experiences based on routine investigation of electrical interference. We describe the special instrumentation developed, the method of investigation adopted and the most common interference problems encountered. We also review the manufacturer's contribution.

Electricity↗