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C Edwards

Publications and source records attributed to C Edwards.

At least 361 records · Page 20Linked to original sources
PubMed1969

The permeation of non-electrolytes through the single barnacle muscle cell.

The rate of movement of non-electrolytes and tritiated water (THO) across the muscle cell membrane of the giant barnacle Balanus nubilus has been studied and permeability coefficient calculated. The rate of permeation is more closely related to the oil-water partition coefficient than to size of the molecule or degree of hydrogen bonding. Calculations based on efflux from an ideal cylinder suggest that the membrane acts as a significant barrier to movement of these molecules. The cell was unable to concentrate dimethyl sulphoxide (DMSO); the steady state was reached at about 60% of the extracellular concentration. The energies of activation for water, urea and DMSO are 7.5, 20.3 and 26.1 kcal/mol. At 4 degrees C the apparent pore size measured with urea, glycerol and DMSO was 3.5 A. At 25 degrees C the apparent pore size for urea and glycerol is unchanged but that for DMSO is 14 A.

Animals↗
PubMed1967

Why my assistant?

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Dental Assistants↗
PubMed1966

The effect of the replacement of calcium by strontium on excitation-contraction coupling in frog skeletal muscle.

1. In frog skeletal muscle strontium can replace calcium in potassium contractures for 5 hr, though it is less effective than Ca. Sr can restore the responsiveness to K after it had been lost in the presence of Mn.2. Muscles refractory to caffeine following repeated exposure to it in the absence of Ca, recover in part following addition of Sr.3. The uptake of (85)Sr was increased during mechanical activity, whereas the uptake of (58)Co was not changed. Resting uptake of (58)Co was 3-4 times greater than that of (85)Sr.4. Sr fully activated the myofibrillar adenosine triphosphatase (ATP-ase), though its affinity was about 30 times less than Ca.5. The sarcoplasmic reticulum took up Sr, though less effectively than Ca.

Adenosine Triphosphatases↗
PubMed1965

Interaction between the effects of inside and outside Na and K on bullfrog skin potential.

The composition of the solution bathing one border of the isolated frog skin affects the response of the potential across the skin to changes in the composition of the solution bathing the opposite border. Increasing the K concentration of the inside (corium) bathing solution decreased the sensitivity of the potential to a change in outside Na concentration. Decreasing the outside Na concentration decreased the sensitivity of the potential to a change in inside K concentration. Increasing the total ionic strength of the outside bathing solution or of both bathing solutions decreased the sensitivity of the potential to a change in outside Na concentration.

Animals↗