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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
5 Pt 2
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pubmed:dateCreated |
1989-12-28
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pubmed:abstractText |
Impulse propagation and histology were studied in adult and neonatal canine Bachmann's bundle. Both showed nonuniform electrical anisotropy: effective longitudinal conduction velocity (theta L) markedly exceeded effective transverse conduction velocity (theta T), and extracellular potential waveforms with transverse propagation were polyphasic. An age difference in theta L (0.80 m/s neonate, 1.31 m/s adult) was found; it could be largely accounted for by a difference in myocyte diameter (4.7 microns neonate, 17.1 microns adult). Close apposition of myocytes in the neonate and development of transverse tubules in the adult may have influenced theta L at each stage. Perimysial septa separated fascicles in both neonatal and adult bundles; however, endomysial septa between individual myocytes were completely developed only in adult bundles. Thus perimysial septa were much more responsible for nonuniform anisotropy and low theta T than endomysial septa. Fascicle diameter and length were greater in the adult, which may have affected transverse propagation. Specialized conduction system cells could not be identified.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:status |
MEDLINE
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pubmed:month |
Nov
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pubmed:issn |
0002-9513
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
257
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
H1446-57
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:2589500-Aging,
pubmed-meshheading:2589500-Animals,
pubmed-meshheading:2589500-Animals, Newborn,
pubmed-meshheading:2589500-Dogs,
pubmed-meshheading:2589500-Electrophysiology,
pubmed-meshheading:2589500-Heart,
pubmed-meshheading:2589500-Microscopy, Electron,
pubmed-meshheading:2589500-Myocardium
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pubmed:year |
1989
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pubmed:articleTitle |
Structure of canine Bachmann's bundle related to propagation of excitation.
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pubmed:affiliation |
Department of Pediatrics, Duke University Medical Center, Durham, North Carolina 27710.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
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