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Biomedical subjects

J H Fremlin

Publications and source records attributed to J H Fremlin.

At least 37 records · Page 2Linked to original sources
PubMed1978

In vivo measurement of calcium by the 37Ar method: a study of the effect of recirculating breath collection systems on the exhalation rate.

A study has been made of the effect that different methods of breath collection have on the measurement of calcium in vivo by the 40Ca(n,alpha) 37Ar method. The effect of open and rebreathing breath collection methods has been examined by using intravenous injections of 133Xe. This study has indicated that comparison of calcium measurements between individuals and between centres is likely to be accurate only if breath is collected on 'open circuit'.

Argon↗
PubMed1978

Problems in the interpretation of the in vivo measurement of calcium by the argon-37 method: an investigation of inert-gas elimination in humans.

An investigation has been made of some physiological problems associated with the interpretation of in-vivo measurements of calcium by the argon-37 method. Inert-gas elimination in humans over a period of several days was studied using i.v. injections of Xe-133. The results imply that the exhalation rate of A-37 formed in bone will be affected by the individual's composition, in particular body fat. Comparison of calcium measurements between individuals and between laboratories is meaningful only if corrections are made for differing individual composition.

Argon↗
PubMed1976

Measurements of neutron spectra at depths in tissue equivalent material for fast neutron beams generated by deuterons on beryllium.

The threshold foil technique has been used to investigate the behaviour in tissue of the spectra of neutron beams produced by the bombardment of thick Be targets with 13-0 and 20-5 MeV deuterons. The results indicate a gradual "softening" with depth in tissue of the spectrum generated by 20-5 MeV deutrons which contrasts with a gradual hardening as reported by other authors. This is discussed in terms of the significance of field size and the methods used for data collection and analysis.

Beryllium↗
PubMed1976

Studies in whole body potassium and whole body nitrogen in newly diagnosed diabetics.

Serial measurements of whole body potassium and whole body nitrogen were carried out in 18 newly diagnosed diabetcs. Initial measurements were made before treatment of diabetes was commenced, and further measurements were carried out following the start of treatment. Six patients required insulin and the remainder were treated either with diet alone (four cases) or with diet and oral hypoglycaemic agents. Significant increases in whole body potassium and whole body nitrogen were noted following control of diabetes.Thesees. These changes were most marked in the patients treated with insulin. The techniques used for measurement of body potassium and nitrogen offer considerable advantages over conventional metabolic balance studies and the results indicate that the losses of potassium and nitrogen during period of poor diabetic control are much greater than that has been realized.

Adolescent↗
PubMed1975

Measurement of liver-cadmium concentrations in patients and industrial workers by neutron-activation analysis.

A new, rapid, non-invasive technique for measuring tissue-cadmium concentrations in patients and industrial workers has been designed and developed with a view to studying the cadmium content of the liver. The method utilises the principle of neutron-activation analysis whereby the specific changes produced by the inter action of nuclei and neutrons are analysed. Liver-cadmium content has been studied in cadavers and in four men with known of suspected cadmium poisoning. The patients all showed very high liver-cadmium levels of between 35 and 200 p.p.m. compared with under 1.0 p.p.m. in non-exposed subjects. The dose of radiation used in clinical studies was 0.4-1.0 rem and the detection limit of cadmium was 1.0 p.p.m.

Adult↗
PubMed1975

Cadmium-its in vivo detection in man.

Neutron capture gamma-ray analysis has been applied to the in vivo detection of Cd in man. The technique was designed for the screening of industrial workers at risk. The limit of sensitivity in a liver-sized phantom is 0-5 ppm for a dose of 0-4 rad. Reproducibility and the effects of positional uncertainties have been investigated. A number of cadavers were studied to establish normal limits prior to commencement of a programme of clinical investigation. A patient with known Cd poisoning was estimated to contain 65-110 ppm of Cd in his liver. A liver dose of 0-05 rad was required.

Activation Analysis↗