351
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Gray S. A minor triumph. THE CANADIAN NURSE 1968; 64:45-6. [PMID: 5658938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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352
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Abstract
Various criteria have been proposed for the diagnosis of left atrial rhythm (LAR) in previous experimental and electrocardiographic studies. Differentiation from A-V junctional rhythms remains ill-defined. In order to assess the left atrial (LA) P wave and to define LAR, the P wave and loop were studied by direct LA pacing in 11 patients undergoing diagnostic transseptal left heart catheterization. Experimental LAR produced changes in P-wave configuration and polarity. These changes were most obvious in lead V
1
and indicated reversal of the sequence and direction of activation with left atrial preceding right atrial depolarization. A typical "dome and dart" P wave occurred in two studies. P-wave configuration in leads I and V
6
was highly variable; frequent orientation of the LA P vector within the transitional zone of the horizontal electrical axis was thought to be responsible. The LA P loop showed reversal of the direction of inscription of the initial forces, indicating a change in the pattern of atrial depolarization. Stimulation of the appendage produced left-to-right spread of atrial depolarization, whereas activation of the main body was directed primarily anteriorly. Impulse formation in the right side of the posterior wall was usually directed from right to left. When the postero-inferior area was activated, the anterior P vector became directed superiorly, and resembled that of coronary sinus rhythm (CSR) in the frontal plane.
This study indicates that the P wave in lead V
1
is most important in the diagnosis of LAR; inversion of the P wave in lead V
6
is not essential. LAR can usually be differentiated from CSR, since in the horizontal plane, activation of the LA main body is more anteriorly directed than the spatial P vector of CSR.
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353
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Mellander S, Johansson B, Gray S, Jonsson O, Lundvall J, Ljung B. The effect of hyperosmolarity on intacet and isolated vascular smooth muscle. Possible role in exercise hyperemia. ANGIOLOGICA 1967; 4:310-22. [PMID: 6075769 DOI: 10.1159/000157715] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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354
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Gray S, Edwards BF. Effect of weightlessness and radiation on the growth of the wheat coleoptile for the purpose of defining and verifying an experiment suitable for use in a biosatellite. NASA CR-303. NASA CONTRACTOR REPORT. NASA CR. UNITED STATES. NATIONAL AERONAUTICS AND SPACE ADMINISTRATION 1965:1-62. [PMID: 5295313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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355
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Gray S, Forrest AD. Azacyclonol in Schizophrenia. West J Med 1958. [DOI: 10.1136/bmj.1.5079.1123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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356
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Gray S. Pupil Teachers in Elementary Schools. West J Med 1897. [DOI: 10.1136/bmj.1.1880.115-c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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