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71.
Scales for the measurement of attitudes toward blood donation   总被引:1,自引:0,他引:1  
Attitudes toward blood donation are frequently assumed to vary along a single dimension from unfavorable to favorable. In contrast, theories of attitude structure specify three distinct attitude components: affect, cognition, and behavior. This article describes the development of three new scales for the measurement of affective, cognitive, and behavioral components of attitudes toward blood donation. The scales were developed using the method of equal-appearing intervals and were administered to both donors of blood and nondonors. Correlations among the scales were relatively small and supported the three-component distinction. Affect was more strongly correlated with the number of prior donations than was cognition, which suggested an important role for emotional factors in blood donation. Scores on all three scales showed the attitudes of blood donors to be more favorable than those of nondonors.  相似文献   
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Twenty-six patients (4 months to 6 years old) with achondroplasia complicated by sleep apnea and/or other neurologic manifestations underwent plain computed tomography (CT) of the craniocervical junction; six also underwent CT myelography. For objectification, multiplanar reconstruction was used to complement axial plane measurements by providing coronal and sagittal measurements; multiplanar reconstruction also improved perception of the longitudinal relationships between the brain stem and subarachnoid space. A narrow subarachnoid space was found in all 26 patients; marked cord compression was present in nine, six of whom underwent CT myelography. These six had marked focal obliteration of the subarachnoid space on both plain CT and CT myelography. Since the subarachnoid space immediately above and below the craniocervical junction is normally capacious, when marked constriction was present, no additional information could have been gained from CT myelography. Thus, plain CT was shown to be sufficient for surgical planning (suboccipital decompression) in nine patients with cord compression due to achondroplasia.  相似文献   
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The metabolism of ethanol (ETOH) is known to increase the cytosolic NADH/NAD ratio and consequently impairs hepatic glucose output in the fasted state. In contrast, one of the characteristic alterations in glucose metabolism produced by the administration of endotoxin is an increase in the de novo synthesis of glucose. Therefore, the present study tests the hypothesis that the acute administration of ETOH will prevent the endotoxin-induced increase in glucose production. In vivo glucose kinetics were determined by the infusion of [6-3H, U-14C]glucose in catheterized conscious rats. The intravenous infusion of tracer glucose, and ETOH (100 mg/100 g b.w./hr) or saline were started at the same time and both continued throughout the experiment. Two hours later the ETOH infusion rate was decreased to maintain the blood ETOH levels between 100 and 160 mg/dl. At 140 min, endotoxin (100 micrograms/100 g b.w.) was injected. ETOH alone did not alter basal values of plasma glucose (5 mM), glucose rate of appearance (Ra; 35 mumols/min/kg) or metabolic clearance (MCR; 7 ml/min/kg). Endotoxin alone increased plasma glucose (80%) and lactate (140%) concentrations, glucose Ra (60%) and recycling (40%) in saline-infused rats, whereas in ETOH-infused animals, plasma glucose and lactate levels were only elevated 40% and glucose Ra and recycling were unchanged. The results show that acute ETOH administration diminishes the increased glucose production and utilization seen in endotoxemia. The attenuation of the endotoxin effect by ethanol is due to inhibition of hepatic glucose production and peripheral glucose utilization.  相似文献   
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Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein.  相似文献   
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