Biomedical subjects
Publications and source records attributed to M Matsuki.
A simple gas chromatographic method for the determination of lidocaine in tissues is described. Lidocaine is extracted from the tissue samples using liquid nitrogen. The recoveries of lidocaine from brain, liver, and muscle were 98.6, 99.8 and 89.1%, respectively. Results were reproducible to within 1.0% of lidocaine administered.
The evoked spinal electrogram (SEG) in man was recorded from the epidural space, applying the technique of continuous epidural block, and compared with cord dorsum potential (CDP) in wakeful rabbits. Wave-form characteristics of the evoked SEG'S activated by the segmental nerves were almost the same in both cervical and lumbar regions. Somatosensory evoked response from the scalp was clearly demonstrated by stimulation of both the tibial nerve and fifth toe skin, whereas the evoked SEG was produced only by stimulation of the former. This finding might indicate that large nerve fibers are more responsible for producing the evoked SEG. Central latencies to the peaks of the second components of the P2 wave were 29 to 33 and 42 to 48 msec, in cervical and lumbar enlargements, respectively. This probably indicates the presence of a long feedback loop producing the second components. The amplitude of the N1 wave showed a steeper decline along the spinal cord than that of the P2 deflection, indicating between origins of these two components. Polarity of both the N1 and P2 waves became reversed when the recording electrode was situated in the anterior epidural space. The wave-form characteristics of the evoked SEG in man were very similar to those of the CDP in wakeful rabbits.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The slow positive wave (P2 wave) of the evoked spinal electrogram was recorded from the posterior epidural space in wakeful man, and studied by applying several modes of peripheral nerve stimulation. With graded stimulation the P2 wave amplitude rapidly reached the maximum at weaker stimulation than that required for the initially positive spikes (P1) and the preceding negative (N1) wave. The "second" component of the P2 appeared during stronger stimulation or during excitemenpt of the subjects. With prolonged repetitive stimulation the P2 wave increased its duration with several summits on the decaying phase. Two interactions were observed between the P2 waves produced by conditioning and testing stimulations in the same or different nerves: inhibition or occlusion by strong stimulation and faciliation by weak stimulation. Thus, the characteristic of the P2 wave in man was similar in part to that of the positive wave observed in decerebrate animals, and differnt in other ways presumably due to influences from supraspinal structures or species differences.
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.
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.