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Biomedical subjects

D S Smith

Publications and source records attributed to D S Smith.

At least 361 records · Page 20Linked to original sources
PubMed1974

Can I have an ambulance, doctor?

In a study of the ambulance service to an outpatient physiotherapy centre in an urban area over half of the palients were aged over 65, a quarter made at least three visits to the centre weekly, and the average travel and waiting times for all patients was about two-and-a-half hours. There was a direct relation between distance from home to the centre and travelling time for morning but not afternoon attenders. A second survey after some changes in the transport arrangements showed some relatively small reductions in overall travelling and waiting time. It is concluded that even under favourable conditions an important side effect of outpatient physiotherapy is the probable fatigue and anxiety generated by ambulance travel.

Ambulances↗
PubMed1973

Exocytosis in the adrenal medulla demonstrated by freeze-etching.

Replicas of fractured chromaffin cells are indicative of a range of activities thought to characterize exocytosis, including attachment of secretory vesicles to the plasma membrane, fusion, extrusion of contents, and membrane retrieval. Exocytosis sites are abundant on stimulated cells but are infrequent when calcium is omitted from the system.

Adrenal Medulla↗
PubMed1973

Freeze-etch studies of the plasma membrane of pulmonary endothelial cells.

Pulmonary endothelial cells are capable of metabolizing a variety of circulating hormonal substances. Indirect evidence indicates that some of the relevant enzymes are located on the plasma membrane. The associated caveolae are of special interest as globular subunits, possibly enzyme clusters, are evident in their membranes. In the present study, freeze-etch techniques were used to improve understanding of the fine structure of endothelial cells and to extend our investigations of possible sites of enzymes capable of metabolizing circulating vasoactive agents. As in other cells studied by freeze-etching, intramembranous particles are found on both inner aspects of the plasma membrane. In undifferentiated areas of plasma membrane, the particles appear to have a random distribution. These areas fracture such that approximately equal proportions of the particles adhere to the cytoplasmic aspect of the outer leaflet and the extracellular aspect of the inner leaflet. However, the particles organize into rosettes and plaques at the base of caveolae, and, after fracture, the rosettes and plaques adhere predominantly to the cytoplasmic aspect of the outer leaflet. The peculiar organization of particles in association with caveolae supports the concept that caveolae have a stomal skeletal structure and raises the possibility that the organization may be in some way related to pinocytosis.

Animals↗