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The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%.  相似文献   
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Postembolic colonic infarction   总被引:12,自引:0,他引:12  
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Most system administrators know what needs to be done to make their systems secure and manageable but these needs are tough to sell to upper management in a tight economy. However, system administrators using industry accepted best practices can calculate a return on investment for budgeting purposes, justifying expenses by comparing them with expected costs if such practices are not in place.  相似文献   
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The world-wide epidemic of Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome (HIV/AIDS) has led to an increase in the number of HIV positive children, mainly through perinatal transmission. HIV/AIDS can lead to severe childhood malnutrition (SCM) and has been noted as an increasingly common cause of secondary SCM. In this context, it is important to make assessments of the appropriateness of current approaches to treatment of severe malnutrition in HIV positive children. A retrospective matched case-control study of ten HIV positive children admitted to the Tropical Metabolism Research Unit (TMRU) was conducted. There were few differences between cases and matched controls on admission to the ward. Oral candidiasis and lower respiratory tract infections appeared to occur more frequently, and serum globulin concentrations were significantly higher among HIV positive cases when compared to their controls. Despite the fact that the differences between cases and controls appeared to be small, four cases died; there were no deaths among the controls. The duration of the maintenance phase was approximately five days longer (p = 0.024) among cases than controls but the time between the end of the maintenance phase and discharge from the ward was not significantly longer for the cases. The results of this matched case-control study suggest that there are likely to be important differences between HIV positive and negative patients with SCM that influence risk of mortality and morbidity, particularly in the maintenance phase of treatment. Prospective studies will be required in order to explore these differences and to develop better approaches to the care of HIV positive children with SCM.  相似文献   
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Weight gain, a common adverse effect of clozapine, may impair health and affect patient compliance during treatment with this agent. The aim of this study was to investigate the relationship between genetic variants of the adrenergic beta3 receptor (ADRB3) and the G-protein beta3 subunit (GNB3) and clozapine-induced body weight change (BWC). Eighty-seven treatment-resistant schizophrenic patients were weighed before and after 4 months of clozapine treatment, with the subjects gaining an average of 2.6 kg in body weight. No statistically significant relationship was demonstrated for the investigated ADRB3 Trp64Arg and the GNB3 C825T polymorphisms in terms of BWC post-treatment, suggesting these two polymorphisms do not play a significant role in clozapine-induced BWC. Further exploration of other genetic variants implicated in clozapine-induced BWC is important, however, in order to predict and reduce clozapine-associated weight gain.  相似文献   
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