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The symbolic and communicative aspects of illness and treatment are examined. A number of factors that complicate interpersonal communication are identified and found to exist in their most extreme form in medical settings. New directions in research and training are suggested that might prepare medical personnel to respond more sensitively and flexibly to the symbolic aspects of illness.  相似文献   
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The effect of ortho-iodo sodium benzoate (OISB) on the oxyhemoglobin dissociation curve of coronary venous blood was studied in an isolated canine heart preparation perfused at a constant coronary blood flow. Changes in P-50 (millimeters of mercury) [the oxygen tension (pO2) at which hemoglobin is 50% saturated], were used to express hemoglobin-oxygen affinity. Intracoronary infusion of OISB (200, 400 and 800 mg/min) produced a dose-related increase in coronary venous P-50 and a concurrent increase in coronary venous pO2. In addition, OISB produced a significant decrease in heart rate and increase in coronary artery perfusion pressure. During cardiac pacing at 150, 190 and 230 beats/min, OISB (400 mg/min) significantly increased coronary venous P-50, myocardial oxygen exrraction (O2E) and oxygen consumption (MVO2) whereas coronary venous PO2 was not changed. Furthermore, a 5-minute intracoronary infusion of OISB (200 mg/min) during myocardial ischemia produced an increase in O2E, MVO2 and myocardial contractility with little change in coronary venous pO2. These results suggest that acute pharmacological manipulation of the oxyhemoglobin dissociation curve may enhance oxygen release to the myocardium while maintaining the effective driving pressure (as reflected in coronary venous pO2) for diffusion of oxygen to the myocardium.  相似文献   
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Management of minor illness   总被引:1,自引:0,他引:1  
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Although the rise in blood copper is associated with onset of the acute haemolytic crisis of chronic copper poisoning in sheep, the sudden fall in erythrocyte glutathione is apparently not due to a direct action of the copper. Moreover the reduced glutathione of the red cells is converted to some form that is not capable of regeneration by the pentose-phosphate mechanism. Only negligible inhibition of the pentose-phosphate enzymes occurs. As the haemolysis proceeds, there is a rapid recovery of erythrocyte glutathione levels, and a marked increase in pentose-phosphate enzyme activity, consistent with influx of young red cells. It seems that the release of copper into blood from liver at the haemolytic crisis is associated with an increase of the oxidative state of the blood, possibly by simultaneous release of other components from the liver.  相似文献   
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