[Value of electromyography in diseases of the peripheral motor neurons. Study of changes in neural conduction in amyotrophic lateral sclerosis].
Explore the source record for details and available documents.
SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
High-voltage condenser discharges exerting a field strength of up to 1000 V/cm (discharge time constant 0.24-8 msec) applied to isolated sciatic frog nerve lead to disturbances of the propagation of action potentials including transient complete block of conduction. Such conduction disturbances are normally reversible within minutes. Inhibition of the activity of the membrane-bound Na+-K+ATPase prevents the recovery from conduction block. Withdrawal of external Ca2+ also prevents recovery, whereas blockade of protein synthesis by cycloheximide has no influence. The velocity of recovery depends on the temperature, with temperature coefficients (Q10) from 1.31 to 1.84 between 2 degrees and 30 degrees C. Transmission electron microscopy of nerves subjected to strong discharges shows alterations of the myelin sheath (splitting and cleft formation) which are, however, not specific for this mechanism of injury. No alterations are seen in the region of the free axoplasmic membrane of the node of Ranvier or in organelles. The results suggest a breakdown of the transmembrane ionic gradient causing the conduction disturbance.
Fourteen patients with chronic glomerulonephritis and with Alport's syndrome were treated. Haemodialysis was performed 2--3 times weekly. The duration of treatment was from 10 months to 9 years. Serum levels of electrolytes, urea and creatinine were determined, the neurological condition was examined and nerve conduction velocity was measured in the lower and upper extremities. The determinations were done before and after haemodialysis. Subclinical manifestations of polyneuropathy were demonstrated with reduced motor-nerve conduction velocity in the lower extremities. A direct effect of single haemodialysis was far from uniform: usually the conduction velocity increased after haemodialysis and in some cases it decreased. There was no correlation between the serum levels of electrolytes, urea and creatinine and motor-nerve conduction velocity.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.