Search PubMed⌕ Search

Biomedical subjects

L Davis

Publications and source records attributed to L Davis.

At least 289 records · Page 16Linked to original sources

Treatment of para-aortic nodes in carcinoma of the cervix.

Thirty-six cases of carcinoma of the cervix with positive pelvic or para-aortic nodesdiagnosed by lymph node scan, lymphangiogram, and/or biopsy have received radiation therapy to the para-aortic nodal area at the Hospital of the University of Pennsylvania. Megavoltage radiation delivering a tumor dose of approximately 5000 rads in 5 weekshas been used. Of 26 patients avaiable for foloowup for 2 years, 11 were alive; of 8 followed for 5 years, 4 were alive. The severe complication rate was 19.5%, with a 5.5% mortality. Conclusions an- implications for further therapy are discussed.

Aorta↗

Principles underlying new methods for chronic neural recording.

Chronic recording is possible from nerve fibers which have grown through holes in an insulating medium (regeneration electrodes) or which are enclosed by an insulating sheath (cuff electrodes). Use of three electrodes in a balanced configuration permits good rejection of electromyographic (EMG) signals and other sources of electrical interference (fluorescent lights, 60 Hz signals from the mains, etc.). Equations are derived and tested for predicting the amplitude and form of the signals expected for a given cuff length and diameter. These equations can be used to design electrode units optimally for a given application. Finally, the use of transformers permits the neural signals to be carefully matched to the recording apparatus and further optimizes the neural signal-to-noise and signal-to-EMG ratios. Use of these methods in several physiological and clinical applications, as well as potential abuses, are discussed.

Animals↗