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G Ironson C B Taylor M Boltwood T Bartzokis C Dennis M Chesney S Spitzer G M Segall 《The American journal of cardiology》1992,70(3):281-285
This study examined the comparative potency of several psychological stressors and exercise in eliciting myocardial ischemia as measured by left ventricular (LV) ejection fraction (EF) changes using radionuclide ventriculography. Twenty-seven subjects underwent both exercise (bicycle) and psychological stressors (mental arithmetic, recall of an incident that elicited anger, giving a short speech defending oneself against a charge of shoplifting) during which EF, blood pressure, heart rate and ST segment were measured. Eighteen subjects had 1-vessel coronary artery disease (CAD), defined by greater than 50% diameter stenosis in 1 artery as assessed by arteriography. Nine subjects served as healthy control subjects. Anger recall reduced EF more than exercise and the other psychological stressors (overall F [3.51] = 2.87, p = .05). Respective changes in EF for the CAD patients were -5% during anger recall, +2% during exercise, 0% during mental arithmetic and 0% during the speech stressor. More patients with CAD had significant reduction in EF (greater than or equal to 7%) during anger (7 of 18) than during exercise (4 of 18). The difference in EF change between patients with CAD and healthy control subjects was significant for both anger (t25 = 2.23, p = 0.04) and exercise (t25 = 2.63, p = 0.01) stressors. In this group of patients with CAD, anger appeared to be a particularly potent psychological stressor. 相似文献
74.
Amir Beker Jacob Erel Abraham Pinchas Shimon Abboud 《Annals of noninvasive electrocardiology》1996,1(4):386-392
Background: The effect of acute myocardial infarction and regional ischemia on the frequency content of the ECG signal has been described by several investigators. In the present study, the feasibility of assessing changes in the QRS spectrum during exercise testing, and whether these changes are related to the occurrence of ischemia were examined. Methods: Spectral analysis of the high resolution ECGs from leads V3, V4, V5, and V6 were performed in two groups of male subjects before, during, and following treadmill exercise testing. Group A included 32 coronary artery disease (CAD) patients, with arteriographically proven >75% obstruction of at least two main coronary arteries, and group B included 30 healthy subjects, without history or symptoms of CAD. Signal averaging and filtering techniques were used in order to enhance the signal-to-noise ratio of the recorded ECGs. The power spectrum of the averaged QRS waveform for the different stages of the exercise testing was computed using a Fast Fourier Transform, and the slope of the linear regression line was found in the frequency range 7.81–249.92 Hz on the plot of log((amplitude)2) versus log(frequency). Results: Regression line slopes immediately after peak exercise were significantly lower for the CAD group than for the healthy subjects in 3 of the 4 examined leads. No significant changes in slopes were found between the two groups at rest or during late recovery. Comparing the differences between slopes at different stages of the test revealed that the difference between postexercise slope and rest slope has lower mean values for the CAD group in all four leads, with a significant difference in lead V6, and for the difference between postexercise slope and recovery slope, lower mean values were found for the CAD group in all four leads, with a significant difference in V5 and V6. Conclusions: These findings indicate that ischemic changes affect the power spectrum of the QRS complex, and result in a steeper regression line on a log-log scale. 相似文献
75.
Cells with Fc gamma receptors from normal donors suppress granulocytic macrophage colony formation 总被引:1,自引:0,他引:1
We investigated the role of normal human marrow cells with Fc receptors for IgG (Fc gamma+) on autologous granulocyte-macrophage colony (GM- CFC) formation. It was found that Fc gamma+ normal human marrow cells, both with (E+) or without receptors for sheep erythrocytes suppressed GM-CFC at as low a concentration as 0.25 X 10(5) cells/ml of culture. A similar effect was observed with E- Fc gamma+ but not E+ Fc gamma+ peripheral blood cells. Suppression by Fc gamma+ cells did not require mitogen activation and was not inactivated by irradiation (2000 R). This report presents a new in vitro regulatory mechanism for GM-CFC growth in normal donors. 相似文献
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78.
Alcohol Consumption in Rats Potentiates the Deleterious Effect of Gram-Negative Sepsis on Hepatic Hyaluronan Uptake 总被引:3,自引:0,他引:3
Ion V. Deaciuc Kathleen H. McDonough Gregory J. Bagby John J. Spitzer 《Alcoholism, clinical and experimental research》1993,17(5):1002-1008
The role of hepatic sinusoidal endothelial cells (SECs) in the pathologic changes of the liver associated with alcohol consumption is not fully understood. The measurement of hyaluronan (HA) uptake by the SECs provides a useful means for assessing the functional state of these cells. In this study, we determined the effect of acute and chronic exposure to alcohol in rats in the absence and presence of subcutaneous Escherichia co/i-induced sepsis on plasma HA concentration and HA uptake by the isolated, perfused liver. Rats were administered ethanol (two doses of 0.2 g/100 g body weight, intraperitoneal, 24 and 15 hr before killing) or fed a liquid diet for 8–10 weeks, containing alcohol (36% of the total calories) or dextrin (in isocaloric amounts). Twenty-one hr before euthanizing for liver perfusion, animals were injected subcutaneously with live E. coli (sepsis) or sterile saline (control). Neither acute nor chronic alcohol exposure by themselves altered plasma HA levels. However, both treatments exacerbated the hyperhyaluronanemic effect of sepsis. Thus, in acutely alcohol-treated rats, sepsis induced a 187% (p &< 0.05) increase in plasma levels of HA, whereas in nonalcohol septic rats, the increase was only 54% (p &< 0.05). Likewise, sepsis resulted in a greater increase in the plasma levels of HA (871%) in alcohol-fed rats than it did in liquid diet, control-fed rats (323%, p &< 0.05). The rate of HA uptake by the isolated, perfused liver was not altered by either acute or chronic alcohol exposure. However, alcohol exposure markedly potentiated the inhibitory effect of sepsis on the capacity of the liver to take up HA. Thus, in acutely alcohol-treated rats, sepsis decreased HA uptake (60-80%, p &< 0.05), whereas in the corresponding nonalcoholic control group the decrease was evident only at the beginning of HA infusion. In chronically alcohol-fed rats, sepsis induced an 80% (p &< 0.05) inhibition of HA uptake, whereas in diet-fed control rats the inhibition was only 60% (p &< 0.05). The inhibition by sepsis of HA uptake by the isolated, perfused liver provides an explanation for the previously observed hyperhy-aluronanemia in septic humans and animals. Because alcohol alone does not alter HA metabolism, the results suggest that acute and chronic alcohol exposure influences the communication between liver cells leading to downregulation of HA clearance by SECs. 相似文献
79.
B. Joseph Elmunzer Rebecca L. Spitzer Lydia D. Foster Ambreen A. Merchant Eric F. Howard Vaishali A. Patel Mary K. West Emad Qayed Rosemary Nustas Ali Zakaria Marc S. Piper Jason R. Taylor Lujain Jaza Nauzer Forbes Millie Chau Luis F. Lara Georgios I. Papachristou Michael L. Volk Valerie Durkalski 《Clinical gastroenterology and hepatology》2021,19(7):1355-1365.e4
80.
Spitzer TR Friedman CJ Bushnell W Frankel SR Raschko J 《Bone marrow transplantation》2000,26(2):203-210
The efficacy and safety of granisetron and ondansetron for the prophylaxis of nausea and vomiting resulting from hyperfractionated total body irradiation (TBI) were assessed. Thirty-four patients randomly received double-blind, oral granisetron (2 mg, 1 h before first daily fraction of radiation) or ondansetron (8 mg, 1.5 h prior to each fraction of TBI). Ninety patients who received the same TBI regimen prior to bone marrow transplantation (BMT), but no 5-HT3-receptor antagonist, were identified and comprised the historical control group. By design, this study was only powered to show a difference between each of the active treatment groups and the historical control group. Significantly more patients given granisetron (33.3%) or ondansetron (26.7%) had zero emetic episodes over 4 days, the primary efficacy end point, than those in the historical control group (0%) (P < 0.01; intent-to-treat). Secondary efficacy end points were also evaluated. During the first 24 h, significantly more patients taking granisetron (61.1%) or ondansetron (46.7%) had zero emetic episodes than patients in the historical control group (6.7%) (P < 0.01). Complete emetic control (no emesis or rescue antiemetic) over 4 days was more frequent in patients taking granisetron (27.8%) or ondansetron (26.7%) compared with the historical control group (0%) (P < 0.01). Significantly fewer patients taking granisetron (18/18), but not those taking ondansetron (12/15), experienced more than five emetic episodes during the 4 days of the study compared with the historical control group (40/90; P < 0.01). Oral granisetron and ondansetron are safe and effective for the prevention of nausea and vomiting resulting from TBI. 相似文献