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21.
To examine the effects of recombinant human erythropoietin (rHuEPO) on hospital utilization, hospital costs, and Medicare reimbursements for hospital care, a longitudinal, matched cohort study was conducted using Medicare claims data of 23,806 Medicare-eligible, dialysis patients who received rHuEPO, did not have a transplant, and were alive for 18 mo or longer and 22,720 controls matched on age, sex, race, cause of ESRD, and dialysis modality. The relative odds (rHuEPO versus control) of admission for all causes and for specific causes over 9 mo, adjusted for admission in the prior 9 mo and the per patient change in total admissions, inpatient days, hospital costs, and Medicare hospital payments between the prior 9-mo period and the subsequent 9-mo period was examined. The adjusted relative odds (95% confidence interval) of admission (rHuEPO versus control) was: higher and statistically significant for all causes, 1.08 (1.03 to 1.14); seizure, 1.52 (1.28 to 1.75); vascular access revision, 1.11 (1.06 to 1.17), and heart failure, 1.17 (1.09 to 1.26); higher but not statistically significant for angina, 1.09 (0.99 to 1.20) and stroke, 1.08 (0.86 to 1.31); and lower but not statistically significant for myocardial infarction, 0.91 (0.72 to 1.10); peripheral vascular disease, 0.81 (0.60 to 1.02); anemia, 0.86 (0.56 to 1.17); and depression, 0.89 (0.37 to 1.40). The mean change per 1,000 patients in admissions was less by 38 (P = 0.03) because of fewer readmissions, and in days was 1,309 less (P < 0.001), for patients treated with rHuEPO versus controls. The mean change per patient in hospital costs was $371 less and was statistically significant (P = 0.03) and in Medicare hospital payments was $132 less but was not statistically significant (P = 0.43) for patients treated with rHuEPO versus controls. rHuEPO was associated with an increase in the probability of hospital admission (particularly admissions potentially related to adverse effects) but a decrease in readmissions, overall admissions, hospital days, and cost to hospitals in this cohort of patients surviving for 18 mo. Although not realized short term, Medicare savings from potential rHuEPO-related reductions in hospital care may be long term through future adjustments in diagnosis-related group-based hospital payment.  相似文献   
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The bright plumage of male ducks in sexually dichromatic species is thought to have evolved through intense sexual selection. This study examined the relationship between the timing and speed of moult into this bright plumage and subsequent mating success of male harlequin ducks, Histrionicus histrionicus. Males that moulted relatively slowly had a lower chance of establishing a pair bond than others. The timing of moult was unrelated to whether a male obtained a mate. Moult speed and timing were not correlated within individual males, but were significantly repeatable in individual males over 2 years. Moult speed probably reflects the condition of males, whereas timing of moult is more likely to be related to the distance to an individual's breeding area, which determines the timing of arrival to the moulting grounds. In waterfowl species that have been studied, males usually form dominance hierarchies before pairing and females tend to choose dominant males. We suggest that male harlequin ducks that moult slowly are poor-quality individuals, which are relegated to subordinate status and are unlikely to attract a mate the following autumn. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.  相似文献   
23.
Following bar-press shaping of 24 male albino rats to a discrete-trial fixed-ratio (FR) 5 schedule of reinforcement; 16 were trained to produce either hippocampal theta (7.5-8.5 Hz) or nontheta (4-5 Hz) activity, while 8 served as a matched interreinforcement time control (yoked to the theta group). All Ss then returned to the FR-5 schedule on the lever response for 15 days, followed by 12 days of extinction. Results indicate that hippocampal theta production was learned more slowly than nontheta production but resulted in increased resistance to extinction of the subsequently performed lever response. These data are viewed as supporting the hippocampal theta-frustration hypothesis proposed by H. Glazer in 1972. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Reports an error in "Task control and cognitive abilities of self and spouse in collaboration in middle-aged and older couples" by Cynthia A. Berg, Timothy W. Smith, Kelly J. Ko, Nancy J. M. Henry, Paul Florsheim, Gale Pearce, Bert N. Uchino, Michelle A. Skinner, Ryan M. Beveridge, Nathan Story and Kelly Glazer (Psychology and Aging, 2007[Sep], Vol 22[3], 420-427). Due to an editing mistake, the order of authorship was incorrect. The correct order is as follows: Berg, Smith, Ko, Beveridge, Story, Henry, Florsheim, Pearce, Uchino, Skinner, & Glazer. (The following abstract of the original article appeared in record 2007-13103-002.) Collaborative problem solving may be used by older couples to optimize cognitive functioning, with some suggestion that older couples exhibit greater collaborative expertise. The study explored age differences in 2 aspects of collaborative expertise: spouses' knowledge of their own and their spouse's cognitive abilities and the ability to fit task control to these cognitive abilities. The participants were 300 middle-aged and older couples who completed a hypothetical errand task. The interactions were coded for control asserted by husbands and wives. Fluid intelligence was assessed, and spouses rated their own and their spouse's cognitive abilities. The results revealed no age differences in couple expertise, either in the ability to predict their own and their spouse's cognitive abilities or in the ability to fit task control to abilities. However, gender differences were found. Women fit task control to their own and their spouse's cognitive abilities; men only fit task control to their spouse's cognitive abilities. For women only, the fit between control and abilities was associated with better performance. The results indicate no age differences in couple expertise but point to gender as a factor in optimal collaboration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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From the editor.     
Introduces this special issue of the International Journal of Play Therapy, which is divided into three sections. The first presents a view of the future of play therapy; that is, what the profession of play therapy will become in the next century. The second section is intended to provide a context for the research award article. The third section is the 1998 Student Research Award. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
28.
This study examined affective organizational commitment (AOC) and continuance organizational commitment (COC) as moderators of the relationship between job-related anxiety and intention to leave among 506 Israeli nurses who completed self-administered surveys. Prior research examining organizational commitment as a moderator between stress-related variables has shown inconsistent results, most probably because organizational commitment was tested as a moderator of stressor-strain relationships. Both AOC and COC buffered the relationship between job-related anxiety and intention to leave the hospital (i.e., the positive relationship was not as strong with high levels of commitment). There was no buffering effect on the relationship between role stressors and intention to leave. Further, the relationship between job-related anxiety and intention to leave increased more strongly for low levels (vs. high levels) of COC. Implications for the role of organizational commitment in stress models and implications for hospital administrators are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
29.
A specific interaction of [3H]Glu with T lymphocytes from the blood of healthy donors (Kd = 0.236 microM) was revealed and described. It was found that unlabeled quisqualate, a structural analogue of L-glutamic acid, and unlabeled dipeptides Ala-Glu, Glu-Ala, and Glu-Glu competitively inhibit the specific binding of [3H]Glu to T lymphocytes (with Ki 0.19, 2.4, 3.4, and 1.2 microM, respectively). Binding experiments with conjugates of labeled and unlabeled glutamic acid with dextran showed that the receptors of [3H]Glu are localized on the outer surface of the plasma membrane of T lymphocytes.  相似文献   
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