Search PubMed⌕ Search

Biomedical subjects

J C Robertson

Publications and source records attributed to J C Robertson.

30 records · Page 2Linked to original sources
PubMed1975

Pressure measurements beneath below-knee amputation stump bandages: elastic bandaging, the Puddifoot dressing and a pneumatic bandaging technique compared.

Elastic wrap bandaging is unreliable and dangerous in terms of pressure and pressure distribution (tourniquet effect). The Puddifoot dressing is safe and is less likely to produce a tourniquet effect. The range of pressures it produces is low--possibly too low to achieve ideal moulding or oedema control. A pneumatic bandage achieved a relatively narrow range of pressures between capillary and arteriolar blood pressures. It minimized tourniquet effects and differences between skilled and unskilled bandagers. It is sufficiently promising to merit development.

Amputation Stumps↗
PubMed1974

Splinter haemorrhages, pitting, and other findings in fingernails of healthy adults.

Splinter haemorrhages, pitting, transverse grooving, ridging, and flaking occur often in the fingernails of the healthy. While they may occur more often in certain diseases they have little diagnostic value in the absence of proper methods of measurement and examination and without a range of normal values for the sexes and age groups.

Adolescent↗
PubMedDate not supplied

Influence of temperature and membrane lipid composition on the osmotic water permeability of teleost gills.

Osmotic water uptake was measured gravimetrically in isolated, ligated gill arches from trout (acclimated to and incubated at 5 degrees and 20 degrees C) and tilapia (21.5 degrees and 33 degrees C). For both species, incubation of arches at the higher temperature led to 1.5- to 3-fold greater measures of water weight gain. However, gills from warmer-acclimated trout and tilapia had 1- to >3-fold lower the initial rate and 1.5- to >2.5-fold lower the extent of water uptake seen in colder-acclimated conspecifics. Both the incubation temperature sensitivity and the acclimation effects are consistent with transmembrane water permeation. Calcium-free incubations (permitting paracellular water movement) also indicated that interfacial cell membranes contribute to gill permeability characteristics; without calcium, trout gill osmotic water uptake values increased 1.5- to 2-fold, and the temperature dependence of water uptake decreased (initial rate) or was eliminated (extent). The specific contribution of cholesterol to restricting barrier membrane water permeability was indicated by concentration-dependent increases in water uptake in the presence of either nystatin (a cholesterol-complexing, pore-forming agent) or methyl-beta-cyclodextrin (which selectively depletes membrane cholesterol). In addition, a cholesterol-specific cytochemical probe (filipin) intensely labeled the apical surface membranes of trout and tilapia gill epithelium. In summary, these studies implicate membrane cholesterol in determining water permeability in fish gills.

Adaptation, Physiological↗