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Activity of Na+/K+-ATPase and of Ca++-ATPase under the action of adenosine triphosphate in experimental myocardial hypertrophy. ROMANIAN JOURNAL OF PHYSIOLOGY : PHYSIOLOGICAL SCIENCES 1998; 35:303-11. [PMID: 11061329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
This paper presents the results of our research on the mechanisms involved in the modifications occurring in the activity of ionic pumps (Na+/K+-ATPase and Ca++-ATPase) at the level of the sarcolemma, the sarcoplasmic reticulum and mitochondrial membrane of the myocardial cell in experimental myocardial hypertrophy induced by isoproterenol. We also studied the effects of concomitant administration of adenosine triphosphate. Thus, we found the activity of the sarcolemmal Ca++-ATPase intensely increased under the action of isoproterenol, while Ca++-ATPase activity in the sarcoplasmic reticulum decreased significantly. At the same time, the Na+/K+-ATPase activity decreased both in the sarcolemma and in the sarcoplasmic reticulum. Administration of adenosine triphosphate induces opposite effects, of lower intensity, upon the activity of the two ATPase, that tend to offset the the effects of isoproterenol. This was found in the group of rats given concomitantly both isoproterenol and adenosine triphosphate. A better understanding of the processes involved in those modifications of membrane ATPase activity allows us to consider their different behaviour to isoproterenol and adenosine triphosphate as the expression of intrinsic mechanisms by means of which the myocardial cell intervenes in maintaining a physiological concentration of calcium ions (Ca++) that is necessary both in order to avoid a failure of the contractile apparatus and in order to preserve the mitochondria role of ATP supplier. Our results demonstrate the antiadrenergic action of adenosine triphosphate that attenuates isoproterenol effects on cardiac myocytes.
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2
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Mental stress enhances the sympathetic fraction of QT variability in an RR-independent way. INTEGRATIVE PHYSIOLOGICAL AND BEHAVIORAL SCIENCE : THE OFFICIAL JOURNAL OF THE PAVLOVIAN SOCIETY 1997; 32:220-7. [PMID: 9322112 DOI: 10.1007/bf02688620] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In 10 healthy male volunteers aged 19-20, spectral power of the beat-by-beat QT interval was measured at the Traube-Herring-Mayer (THM) band (0.05 to 0.15 Hz) when the subject was at rest and during atrial pacing. After resting in dorsal decubitus for 10 minutes, right atrial pacing was performed at a slight elevation above sinus rhythm as well as at 100 or at 110 beats per minute for 7 minutes each. In addition, during pacing at 100 or 110 bpm, the subject was required to perform a Kraepelin Arithmetic test. There was a statistically significant increase in QT spectral power at the THM band, while heart rate was maintained unchanged during the periods of mental stress versus rest. This experiment confirms the potential independence of the QT interval from heart rate and suggests that THM fraction of QT spectral power has a double subordination: during relaxed rest it follows mostly RR-fluctuation; during stress an RR-independent contribution is added, which presumably reflects the supra-normal sympathetic drive on the ventricles.
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Research on some metabolic and enzymatic modifications in experimental hypertensive myocardium. ROMANIAN JOURNAL OF PHYSIOLOGY : PHYSIOLOGICAL SCIENCES 1995; 32:45-58. [PMID: 8896075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This paper presents our research on metabolic and enzymatic changes in the experimental, Isoproterenol-induced (ISO) hypertensive myocardium of rats. We analyze the effects produced by the simultaneous administration of adenosinetriphosphate (fosfobion) (FOS) and Isoproterenol on the changes in the body weight/heart weight ratio, and on the biochemical changes of cardiac metabolism. We studied the following parameters in the myocardium tissue and blood: plasmatic and tissular creatinin-phosphokinase, Na+K+ ATP-ase in the sarcolemma and the sarcoplasmic reticulum, Ca+2 ATP-ase in the mitochondrial membrane, sarcoplasmic reticulum and sarcolemma, as well as plasmatic and tissular lactate. Our data show an increase of heart weight to 939 mg, compared to 752 mg in the control group, while the heart weight/body weight ratio (mg/g), which was 3.8 in the control group, increased to 5.8 in the group to which Isoproterenol (ISO) was administered, and to 5.2 when fosfobion was associated. Investigation of myocardial metabolism has also shown the fact that under the influence of Isoproterenol, plasma creatinin-phosphokinase rises by 20%, while the association of fosfobion reduces it, in the myocardium tissue, down to 73%, in comparison with the values in the control group. Significant changes were found in the myocardium lactate that decreased by 26% under ISO influence, in comparison with normal values, and that decreased by 90% when FOS and ISO were administered together. This study produces arguments about metabolism-induced cardiac changes under the action of ISO and also contributes to the identification of ways that lead to cardiac hypertrophy. The experiment also demonstrates that the ATP-ases responsible for ion transportation across the membrane are actively involved in myocardium hypertrophy. The disturbances occurring in the investigated enzymatic systems are closed related with the myocardial metabolic ones. Fosfobion does not prevent the appearance and development of Isoproterenol-induced myocardial hypertrophy, but diminishes the increase of myocardial lactate produced by this synthesised catecholamine. At the same time, fosfobion significantly decreases the activity of Ca+2 ATP-ase in the plasmalemma and increases the activity of the Na+ - K+ ATP-ase both in the plasmalemma and in the sarcoplasmic reticulum, indirectly favouring the mechanical processes of cardiac myocytes relaxation. The study of the enzymatic activity of Na+K+ and Ca+2 ATP-ases in our experimental conditions contributes to a better understanding of the mechanisms that produce myocardial and coronary disturbances in myocardial hypertrophy.
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The influence of age on the thermal transition of serum albumine in rats. ROMANIAN JOURNAL OF PHYSIOLOGY : PHYSIOLOGICAL SCIENCES 1995; 32:107-10. [PMID: 8896083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Serum albumine from rats at different ages (1, 3, 9, 18 months) undergoes a thermal reversible denaturation in the range of 40-53 degrees C. Thermal transitions of unbuffered solution of native protein show a significant change of pH as they became heat denaturated. The protein molecule has been analysed in melting studies, manifested by cooperative dissociation of protons and it experiences a decrease in temperature transition with the younger the rats.
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Hypobaric hypoxia: dual sympathetic control in the light of RR and QT spectra. ROMANIAN JOURNAL OF PHYSIOLOGY : PHYSIOLOGICAL SCIENCES 1994; 31:47-53. [PMID: 8640367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
ECGs of 21 candidate-pilots and 19 pilots were recorded during: 1) exposure to 5500 m hypobaric hypoxia (HH) while sitting, in the sequence: 1a) initial 7 min of adaptation (A); 1b) later 7 min of recovery (R) after short but intense tread-mill effort; and 2) final 7 min baseline (B), while sitting and requested to relax, at "0 m altitude" in the hypobaric room. RR and QT short-term variability were studied using spectral powers within Traube-Hering-Mayer (THM: 0.05-0.15 Hz) and respiratory (RESP: 0.2-0.4 Hz) bands. Mean RR proved highest capability to aggregate individual response-profiles: 15 pilots and 9 candidates entered the main (normal) cluster, featured by a comparison "triangle" set as expected: A > R < B > A. QT-THM power closely followed: 10 subjects (ss) in very normal cluster, defined as: A < R > B < A, while secondary clusters in candidates and pilots were interpreted by not-successful relaxation and exaggerated start-effects, respectively. Subjects with QT-THM normal clusters (A < R > B < A has group averages, p < = 0.05), also showed a quasi-normal "triangle" for mean RR, (A = R < B > A). During adaptation to hypoxia, pilots' QT-THM was higher than candidates' one (p < 0.02, Wilcoxon test). Study supports the emerging capability of QT-THM spectral power to index ventricular sympathetic control. Exposure to hypobaric hypoxia proved to be in these subjects a psycho-physiologic rather than a purely physiologic test.
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[Myocardial repercussions during the evolution of liver cirrhosis]. REVUE ROUMAINE DE PHYSIOLOGIE (BUCHAREST, ROMANIA : 1990) 1990; 27:143-54. [PMID: 2135738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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7
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[Effect of anticholinergics on cardiovascular reactivity in subjects with essential arterial hypertension being administered a sympathetic agonist]. PHYSIOLOGIE (BUCAREST) 1988; 25:191-9. [PMID: 2853373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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8
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[Cardiodynamic changes produced by physical effort performed in a hyperthermic environment]. PHYSIOLOGIE (BUCAREST) 1986; 23:245-8. [PMID: 3103143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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9
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[Hormonal and electrolytic changes due to exposure to exogenous hyperthermia and the effect of physical effort on them]. PHYSIOLOGIE (BUCAREST) 1986; 23:99-105. [PMID: 3088621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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10
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[Cardiodynamic changes caused by physical exertion at simulated altitude (4000 m) and under the influence of oxygen inhalation with intrapulmonary hyperpressure]. PHYSIOLOGIE (BUCAREST) 1984; 21:127-32. [PMID: 6429684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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11
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Surgical stress and circadian rhythm of cardiac dynamics. PHYSIOLOGIE (BUCAREST) 1982; 19:67-72. [PMID: 6810394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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12
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The influence of day and night work on the circadian variations of cardiovascular performance. EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY AND OCCUPATIONAL PHYSIOLOGY 1982; 48:11-23. [PMID: 7199446 DOI: 10.1007/bf00421160] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Circadian variations of the pre-ejection period, Q-T interval, heart rate and oral temperature at rest and in day and night shift work were investigated. At rest, pronounced circadian variation was found in heart rate, pre-ejection period and Q-T interval. The ratio between Q-T interval and heart rate also shows a distinct circadian variation. When working, the rest rhythms of the variables were obscured. The physiological implications for shift work are discussed.
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13
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[Left axial deviation and anterior left fascicular block]. PHYSIOLOGIE (BUCAREST) 1981; 18:61-4. [PMID: 6794053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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14
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[Exogenous hyperthermia and water-electrolyte homeostasis]. PHYSIOLOGIE (BUCAREST) 1980; 17:85-90. [PMID: 6770389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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15
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[Modification of cardiac dynamics in intraventricular conduction disorders]. PHYSIOLOGIE (BUCAREST) 1980; 17:139-44. [PMID: 6770385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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16
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[Left branch block with strong left axial deviation; electrocardiographic and vectorcardiographic aspects]. PHYSIOLOGIE (BUCAREST) 1979; 16:25-36. [PMID: 106414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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17
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[Capacity for physical effort in a group of children 6 to 7 years of age as a function of sex, physical activity and of certain parameters of body development]. PHYSIOLOGIE (BUCAREST) 1978; 15:207-14. [PMID: 106403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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18
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[Right branch block associated with anterior left hemiblock; electrocardiographic and vectorcardiographic aspects]. PHYSIOLOGIE (BUCAREST) 1978; 15:269-78. [PMID: 106412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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19
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[Problems of electrocardiographic and vectorcardigoraphic diagnosis in postero-basal myocardial infarct and in right branch block]. PHYSIOLOGIE (BUCAREST) 1978; 15:107-11. [PMID: 97684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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20
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Circadian synchronization and desynchronization of some cardiodynamic parameters in reversed activity-rest cycle. PHYSIOLOGIE (BUCAREST) 1978; 15:23-7. [PMID: 417350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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21
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[Changes in the activity of the heart and cerebral and peripheral circulation produced by a moderately hypoxic and hyperthermal environment]. PHYSIOLOGIE (BUCAREST) 1978; 15:11-6. [PMID: 417348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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22
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[Syncope in flight personnel. Physiopathologic and polygraphic aspects]. PHYSIOLOGIE (BUCAREST) 1977; 14:303-11. [PMID: 413131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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23
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[Modifications of catecholamines and uropepsinogen detected after exposure to an altitude of 2,200m in a barometric-pressure chamber under normal conditions and under hyperthermia]. PHYSIOLOGIE (BUCAREST) 1977; 14:159-63. [PMID: 411141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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24
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[Various problems in intermittent intraventricular conduction]. PHYSIOLOGIE (BUCAREST) 1977; 14:185-92. [PMID: 411144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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25
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[ECG and vectorcardiographic studies of the diagnosis and localization of old myocardial infarcts]. PHYSIOLOGIE (BUCAREST) 1977; 14:89-94. [PMID: 405691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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26
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[Physical capacity (W 170 in children and adolescents in relation to sex and physical training]. PHYSIOLOGIE (BUCAREST) 1976; 13:261-9. [PMID: 828743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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27
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[The significance of left axial deviation; electrocardiographic and vetorcardiographic studies]. PHYSIOLOGIE (BUCAREST) 1976; 13:181-4. [PMID: 828732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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28
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Investigations on rheoencephalographic changes produced by orthostatism and the Valsalva manoeuvre, and the compensatory influence of the anti-G suit. ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY 1971; 30:360. [PMID: 4103520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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29
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[On the vestibular syndrome after craniocerebral injury in flight personnel]. OTO-RINO-LARINGOLOGIE 1971; 16:35-41. [PMID: 5313770] [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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30
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[Electropolygraphic examinations in aviation flight personnel]. NEUROLOGIA, PSIHIATRIA, NEUROCHIRURGIA 1970; 15:133-43. [PMID: 5423693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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31
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EEG alterations in athletes in the barochamber at 5000m altitude. ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY 1969; 27:638. [PMID: 4188875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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32
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EEG investigations in aircraft crews. ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY 1969; 27:629. [PMID: 4188838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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33
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[Investigations on the morphology of the carotid sphygmogram in hypertension and the influence of postural changes on the latter]. FIZIOLOGIA NORMALA SI PATOLOGICA 1966; 12:211-21. [PMID: 5964344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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34
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[Research on the dynamics of cardiac contraction in arterial hypertension]. STUDII SI CERCETARI DE FIZIOLOGIE 1966; 11:231-239. [PMID: 5966098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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35
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Investigations on the cardiovascular reactions produced by the Valsalva manoeuvre and the influence of the anti-G suit upon these reactions. RUMANIAN MEDICAL REVIEW 1966; 20:3-9. [PMID: 5328107] [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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36
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[Research on some cardiovascular reactions produced by Valsalva's maneuver and influence of the anti-G suit on them]. FIZIOLOGIA NORMALA SI PATOLOGICA 1965; 11:153-60. [PMID: 5843032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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