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Domen developed a sealed water calorimeter at NIST to measure absorbed dose to water from ionizing radiation. This calorimeter exhibited anomalous behavior using water saturated with gas mixtures of H2 and O2. Using computer simulations of the radiolysis of water, we show that the observed behavior can be explained if, in the gas mixtures, the amount-of-substance of H2 and of O2 differed significantly from 50 %. We also report the results of simulations for other dilute aqueous solutions that are used for water calorimetry—pure water, air-saturated water, and H2-saturated water. The production of H2O2 was measured for these aqueous solutions and compared to simulations. The results indicate that water saturated with a gas mixture containing an amount-of-substance of H2 of 50 % and of O2 of 50 % is suitable for water calorimetry if the water is stirred and is in contact with a gas space of similar volume. H2-saturated water does not require a gas space but O2 contamination must be guarded against. The lack of a scavenger for OH radicals in “pure” water means that, depending on the water purity, some “pure” water might require a large priming dose to remove reactive impurities. The experimental and theoretical problems associated with air-saturated water and O2-saturated water in water calorimeters are discussed.  相似文献   
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Examined the impact of illness intrusiveness (ILI) on quality of life (QOL) in 99 patients with end-stage renal disease. Ss were interviewed twice, 6 wks apart, to determine differences in perceived ILI across treatment modalities, life domains, and time. Life domains were affected differentially across treatments. Perceived ILI correlated significantly with treatment time requirements, uremic symptoms, intercurrent nonrenal illnesses, fatigue, and difficulties in daily activities. Significant QOL differences emerged across treatment modalities for satisfaction/happiness and pessimism/illness related concerns but not for depression/distress. Perceived ILI correlated significantly with each of these QOL measures. Findings substantiate the construct of ILI as a mediator of the psychosocial impact of chronic, life-threatening illness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Comparative study of the cardioprotective effect of antioxidants emoxipin and hystochrom was conducted in patients with chronic ICD during and after operation for aorto-coronary shunting. Both drugs effectively inhibited LPO activation and reduced the reperfusion damage to the myocardium recorded according to the release of MB-PCK into the blood. The new antioxidant hystochrom proved to be more effective. Its prevalent effect is associated with its higher antioxidant activity.  相似文献   
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Improved hemodynamics and blood flow have been reported in patients with IABPs who experience cardiopulmonary arrest and require CPR. The following research questions, however, remain unanswered: Is there a more effective method of using IABP to prevent cardiac arrest and the need for CPR? Is the timing of balloon inflation and deflation the same for patients undergoing CPR as it is for patients who do not require CPR? Would earlier or later inflation or deflation further enhance cerebral or systemic blood flow? What are the most effective ways for healthcare staff to maintain competency skills in CPR in patients with IABPs?  相似文献   
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In light of recent studies showing that prostate-specific antigen (PSA) complexes with certain blood proteins, we studied the effects of acute-phase reactants and alpha 2-macroglobulin (A2MG) on serum concentrations of PSA. Serum samples were obtained from 419 men admitted to an acute-care facility. Various acute-phase reactants-including C-reactive protein, alpha 1-acid glycoprotein, alpha 1-antitrypsin, and alpha 1-antichymotrypsin-and A2MG were measured with a Beckman Array analyzer in parallel with determinations of PSA concentrations by two methods, the Hybritech Tandem RIA and the Abbott PSA IMx. Evaluation by Spearman rank correlation revealed a significant negative correlation of A2MG with PSA values (P < 0.01) and (as expected) a positive correlation of age with PSA values (P < 0.001). The former correlation suggests the possibility that patients with high serum concentrations of A2MG may give falsely decreased results for PSA concentrations in serum.  相似文献   
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