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Biomedical subjects

A Black

Publications and source records attributed to A Black.

At least 127 records · Page 7Linked to original sources
PubMed1983

Alveolar deposition of sized particles of 239PuO2 in the mouse.

Data on the alveolar deposition of 239PuO2 particles in the mouse are presented. It is shown that alveolar deposition falls with increasing activity median aerodynamic diameter (AMAD) over the range 0.6 to 2.4 microns. In the mouse, any peak in alveolar deposition must occur at an AMAD of less than 1 micron. Information is also provided on the relative lobar concentrations (RLCs) of 239PuO2. The RLC is greatest in the right apical lobe and increases quite sharply with AMAD. The RLCs of the other lobes of the right lung decline with AMAD. The RLC in the left lobe is relatively unaffected by AMAD.

Aerosols↗
PubMed1981

A short term effect of homogeneous internal irradiation of the mouse lung with 170Tm2O3 particles.

The short term effects on the free macrophage population in the mouse lung, following inhalation of thulium-170 oxide, have been studied, with a view to using the system as a model with which to compare the short term effects of inhomogeneous alpha irradiation. The clearance and distribution of thulium-170 was followed up to 44 days post inhalation. The mice had an initial lung burden (+/- SE) of 6.7 +/- 0.5 microCi 170Tm/g of lung and the pattern of removal of this could be described by a single exponential of half time 31 +/- 4 days. This exposure resulted in a uniform dose of about 24 Gy to the lung. The macrophage population was studied by counting cells lavaged from the lungs at intervals over the period of the experiment. The lung burden of 170Tm2O3 was found to decrease the free macrophage numbers by about a factor of 2 in 14 days with some slight recovery at 6 weeks post inhalation. It was found that nearly 50% of the activity in the lung lobes was removed by the lavages and that this fraction remained constant throughout.

Aerosols↗
PubMed1980

Experience with day stay surgery.

Potential advantages of day stay surgery are cost saving, improved utilization of staff and hospital facilities, and reduction of stress for the paediatric patient and his family. The successful program requires careful case selection, full operating and anesthetic facilities and good follow-up. Day stay surgery was initiated at Royal Alexandra Hospital for Children in 1974. Experience is reviewed in relation to the total number and nature of surgical admissions and the daily utilisation of the facility. Utilization has markedly increased in the past 2 yr. Current practice is reviewed with regard to initial assessment, preparation for surgery and overall management during the day admission. Parental attitudes towards day stay surgery were evaluated indicating both the advantages and the problems encountered. These related mainly to insufficient information, transport difficulties and afternoon operations. Recommendations for improving the day stay service are discussed with special reference to: (1) communication with the parents as to adequate pre-operative explanation, revision of the day stay information pamphlet and improved distribution, and clear postoperative instructions, (2) the timing of operations, and (3) transport and parking facilities.

Ambulatory Surgical Procedures↗
PubMed1976

Polyuria associated with an antibody to vasopressin.

1. A patient with polyuria in whom diabetes insipidus had been diagnosed was treated with Pitressin. Resistance to this therapy developed after 18 months and a circulating antibody to vasopressin was then demonstrated. Withdrawal of therapy led to a fall in titre of the antibody and an increase in maximal urinary concentration. 2. The antibody to vasopressin was associated with the IgA fraction of the serum immunoglobulins and its characteristics are described.

Adult↗
PubMed1975

Exertion and acute coronary artery injury.

Twelve cases of myocardial infarction as related to strenuous exertion are presented with the pathological findings in several of these cases. Three cases with coronary arteriography are also presented. The pathology of coronary arteriosclerotic plaques and the vulnerability to acute injury is reviewed and discussed. It is concluded that strenuous exertion can cause acute injury to coronary artery plaques due to the unusual stressful whip-like action to which coronary arteries are subject. These injuries may initiate as cracks in the plaques or subintimal hemorrhages and proceed to coronary occlusion and ultimate myocardial infarction. With this concept in mind we use the term of "crack in the plaque" (Black's Crack in the Plaque) to account for the sudden appearance of clinical coronary artery disease appearing during or shortly after exertion, or other stressful situations in patients without previous existing evidence of clinical coronary artery disease. This could also account for exacerbation of symptoms or death occurring after exertion in previously quiescent asymptomatic known coronary artery disease subjects. This concept may explain some of the puzzling features of coronary disease.

Adult↗
PubMed1975

Pulmonary deposition of inhaled particles with diameters in the range 2.5 to 7.5 micron.

Monodisperse polystyrene particles of 2.5,5 and 7.5 micron diameter, labelled with technetium-99m, were administered to mouth-breathing subjects respiring at a rate of 10 breaths min-1. Measurements of radioactivity, made with collimated coaxial detectors above and below the chest, were continued for 24 h, when it was considered that all particles remaining represented those deposited in the pulmonary region. Measurements, made following the ingestion of labelled particles, showed that material in the gut contributed to the counting rate in the chest region even after 24 h. The results showed that in healthy non-smokers, of the material deposited below the level of the larynx, 84% of 2.5 micron, 65% of 5 micron and 30% of 7.5 micron particles were deposited in the pulmonary region. Lateral scans of the chest were also made. These enabled the position of the maximum activity on either side of the midline to be determined. The significance of these measurements is discussed.

Aerosols↗