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11.
Age-density fractionation, in-vitro erythrophagocytosis, and enumeration of membrane-bound antibodies were monitored for circulating red blood cells (RBC) from five anemic patients with myelodysplastic syndromes (MDS), in relation to administration of recombinant human erythropoietin (rhEPO). The density distribution patterns of erythrocytes from the patients prior to treatment were in accordance with their inability to produce compensating levels of circulating RBC. The complete response of one patient to rhEPO and partial responses of two other patients were accompanied by shifts to larger proportions of low density (young) RBC. In vitro phagocytosis of density-fractionated RBC from the complete responder was similar to those of age-matched non-anemic donors. Elevated erythrophagocytosis prior to rhEPO administration was observed for the partial responders and further increased during treatment in one, suggesting the stimulation of abnormal progenitors producing highly defective erythrocytes. There was no correlation between levels of erythrophagocytosis and RBC membrane-bound immunoglobulins in this group of patients. Our findings suggest that density distribution analysis of circulating RBC coupled with in vitro erythrophagocytosis may provide useful predictive tools for selecting potential responders to rhEPO administration among anemic MDS patients. 相似文献
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The osmotic pressure of very dilute liquid mixtures of3He in4He has been measured for the concentration range 0.08–0.6 mole%3He, and the temperature range 20–400 mK. The results are used to check the validity of different proposals for the3He–3He effective interaction.Work supported in part by the Gerald I. Swope Fund and the Batsheva de Rothschild Foundation. 相似文献
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An analytical stochastic model to predict relevant statistical scattering features of electromagnetic waves propagating within vegetated environments is presented. The propagation phenomena are described by formulating the scattering associated with random permittivity fluctuations superimposed on a lossy deterministic background slab. The distorted wave Born approximation is employed to determine the backscattered power, and its temporal spectrum. 相似文献
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Greiffenstein Manfred; Milberg William; Lewis Ronald; Rosenbaum Gerald 《Canadian Metallurgical Quarterly》1981,90(2):105
Current theory suggests that temporal–limbic dysfunction is responsible for schizophrenic symtomatology. Such theory dovetails with many reports of a higher frequency of schizophreniform psychoses in temporal lobe epilepsy (TLE) than is found with other forms of seizure activity. To explore the possibility of a common neurological substrate for the 2 disorders, a variable foreperiod reaction-time task, on which early crossover has been found to be characteristic of many schizophrenics, was administered to 11 schizophrenics, 12 TLE patients, 9 generalized seizure patients, and 10 normal controls. Results show that only TLE and schizophrenic Ss showed an early crossover of regular and irregular preparatory interval gradients. Discussion focuses on the status of crossover as a marker variable, and relevant animal and human lesion literature is reviewed. (45 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Neonatal emergencies have become more common as increasingly sophisticated Neonatal Intensive Care Units graduate lower birth-weight babies born at younger gestational ages. These patients present a number of challenges to emergency physicians. They are often discharged with apnea monitors, which generate a high number of false alarms. Neonatal Intensive Care Unit graduates, however, are predisposed to a number of conditions that can result in true episodes of apnea. We present such a case and will discuss the unusual underlying cause of apnea, the utility of apnea monitors, and the need for emergency physicians to be prepared to evaluate and treat these potentially complicated patients. 相似文献
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Quantifying the turn-on behavior of electrostatic discharge (ESD) protection devices under subnanosecond transients is critical to achieving robust protection against the Charged Device Model stress. A wafer-level very fast transmission-line pulse system (VFTLP) has been developed and is shown to successfully measure the turn-on time of a common ESD protection device. Both formal analysis and practical details regarding VFTLP system construction and operation are documented 相似文献
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Haviland Amelia; Nagin Daniel S.; Rosenbaum Paul R.; Tremblay Richard E. 《Canadian Metallurgical Quarterly》2008,44(2):422
A central theme of research on human development and psychopathology is whether a therapeutic intervention or a turning-point event, such as a family break-up, alters the trajectory of the behavior under study. This article describes and applies a method for using observational longitudinal data to make more transparent causal inferences about the impact of such events on developmental trajectories. The method combines 2 distinct lines of research: work on the use of finite mixture modeling to analyze developmental trajectories and work on propensity score matching. The propensity scores are used to balance observed covariates and the trajectory groups are used to control pretreatment measures of response. The trajectory groups also aid in characterizing classes of subjects for which no good matches are available. The approach is demonstrated with an analysis of the impact of gang membership on violent delinquency based on data from a large longitudinal study conducted in Montréal, Canada. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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