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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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There is no doubt that many pathophysiologic conditions change over a 24-hour period and thus therapy needs to be directed at these changes. In particular, asthma has been one of the better-studied disease processes in regard to circadian changes in pathophysiology. As we continue to learn more about circadian changes, better approaches to treating the disease with the same medications will emerge. It should be remembered that many asthmatics do not perceive their degree of bronchoconstriction. This was brought forth in Turner-Warwick's epidemiologic study in that less than one half of the asthmatic individuals who had problems with their asthma every night describe their asthma as being severe. The majority stated they either had mild or moderate asthma. Therefore, it is important that we use objective criteria such as peak flow meters in determining an individual patient's day-to-night changes in lung function. Then, any therapeutic intervention can be objectively determined at home with both the patient and physician gaining knowledge about the ongoing asthmatic process.  相似文献   
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Differentiation of the concepts of luck and skill.   总被引:1,自引:0,他引:1  
20 Ss from each grade level (kindergarten, Grades 2, 4, 6, and 8) were presented a luck (figures to be matched with a standard were not visible but were on the underside of cards) and a skill (figures were visible) version of a task using items from the Matching Familiar Figures Test. Questioning Ss about the performance of hypothetical others on these tasks revealed 4 levels of differentiation of luck and skill. The least mature Ss focused on the visual complexity of tasks rather than on the fact that the luck task permitted only guessing. On this basis, they expected luck outcomes to reflect effort and considered the luck task to require less effort than the skill task. Only the most mature Ss clearly understood that effort could not affect outcomes on the luck task and selectively attributed skill outcomes to effort and luck outcomes to luck. The most mature Ss also spent less time than did less mature Ss in the face of failure on luck tasks, but spent more time on skill tasks. Findings of age-related differences in the differentiation of skill (effort and ability) and luck and of associated differences in behavior make the analysis of the development of achievement-related cognition and behavior more complete. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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BACKGROUND: Previous studies have suggested altered responses to repeat skin tests in the sites of IgE-mediated late-phase reactions (LPRs) induced within the previous 48 hours. To explore the possible modulation of LPRs in such rechallenge sites, we compared inflammatory responses in skin chambers induced over previous LPR and control sites. METHODS: Skin blisters were induced and unroofed in 12 human subjects over two sites of previous LPRs induced by intradermal injection of pollen antigens 24 hours or 48 hours earlier and two sites previously injected with buffer diluent (B). Skin chambers containing the same antigens were appended to one intradermal antigen site (called Ag/Ag) and one intradermal B site (B/Ag), and B-containing chambers were placed over antigen (Ag/B) and B (B/B) intradermal sites. Fluids were collected after the first and the second through fifth hours of challenge. RESULTS: In skin chamber challenges 24 hours after the intradermal injection, there was no significant difference after the first hours between the Ag/Ag or B/Ag sites in either histamine or tryptase levels; both were significantly higher than at Ag/B or B/B sites (p < 0.01). The same pattern of events was seen in fluids obtained from the second through fifth hours. The same pattern of findings was seen in examination of levels of the total leukocyte accumulation, total eosinophil accumulation, and frequency of activated (EG2+) eosinophils. Levels of lactoferrin, released from activated neutrophils, and eosinophil cationic protein, released from activated eosinophils, were also similar at Ag/Ag and B/Ag sites; both were significantly higher than at B/B sites, whereas levels at Ag/B sites were intermediate between those found at B/Ag and B/B sites. The pattern of events in skin chamber challenges 48 hours after intradermal injection was similar to that seen at 24 hours, except that levels of inflammatory mediators/cells in Ag/B sites were more intermediate between the B/Ag and B/B sites. CONCLUSION: There is no significant alteration of mediator or inflammatory cell responses after antigen rechallenge of previous LPR sites when compared with those found in antigen challenge of non-LPR sites.  相似文献   
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OBJECTIVES: Several studies have noted the impact of socioeconomic factors on access to expensive medical care, but none of those studies controlled for self-reported health and functional status or attitudes about treatment alternatives when analyses were completed. Because these factors may be correlated with socioeconomic status, the failure to control for them may have led to bias in other studies. The authors merged data from secondary sources with telephone survey data from a national sample of 456 end-stage renal disease patients to show how estimates of the effects of socioeconomic factors change when self-reported health and functional status and attitudes about treatment are incorporated into statistical models. The authors also showed how kidney transplant rates would change if socioeconomic factors no longer influences organ allocation decisions. METHODS: Weibull proportional hazard analyses were used to show relationships between socioeconomic measures and waiting list entry and kidney transplant rates, before versus after accounting for self-reported health and functional status, attitudes about treatment, and other variables. Simulation analyses were used to estimate the number of waiting list spots and transplant operations that would move from economically advantaged to disadvantaged persons if socioeconomics no longer influenced organ allocation decisions. RESULTS: Incorporating information about health and functional status, attitudes about treatment, and other factors into the hazard models often reduced the estimated impact of socioeconomic measures on the odds of (1) being on a waiting list for a cadaver kidney transplant and (2) receiving a transplant. Simulations showed that 30 to 65 waiting list spots or transplant operations per 1,000 patients would shift from economically advantaged to disadvantaged persons if socioeconomics no longer influenced organ allocation decisions. CONCLUSIONS: Successful efforts to level the playing field would result in substantial redistributions of kidney transplants from economically advantaged to disadvantaged persons.  相似文献   
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