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71.
Robert J. Town Douglas Wholey Roger Feldman Lawton R. Burns 《Health services research》2007,42(1P1):219-238
Objective. This paper analyzes whether the rise in managed care during the 1990s caused the increase in hospital concentration.
Data Sources. We assemble data from the American Hospital Association, InterStudy and government censuses from 1990 to 2000.
Study Design. We employ linear regression analyses on long differenced data to estimate the impact of managed care penetration on hospital consolidation. Instrumental variable analogs of these regressions are also analyzed to control for potential endogeneity.
Data Collection. All data are from secondary sources merged at the level of the Health Care Services Area.
Principle Findings. In 1990, the mean population-weighted hospital Herfindahl–Hirschman index (HHI) in a Health Services Area was .19. By 2000, the HHI had risen to .26. Most of this increase in hospital concentration is due to hospital consolidation. Over the same time frame HMO penetration increased three fold. However, our regression analysis strongly implies that the rise of managed care did not cause the hospital consolidation wave. This finding is robust to a number of different specifications. 相似文献
Data Sources. We assemble data from the American Hospital Association, InterStudy and government censuses from 1990 to 2000.
Study Design. We employ linear regression analyses on long differenced data to estimate the impact of managed care penetration on hospital consolidation. Instrumental variable analogs of these regressions are also analyzed to control for potential endogeneity.
Data Collection. All data are from secondary sources merged at the level of the Health Care Services Area.
Principle Findings. In 1990, the mean population-weighted hospital Herfindahl–Hirschman index (HHI) in a Health Services Area was .19. By 2000, the HHI had risen to .26. Most of this increase in hospital concentration is due to hospital consolidation. Over the same time frame HMO penetration increased three fold. However, our regression analysis strongly implies that the rise of managed care did not cause the hospital consolidation wave. This finding is robust to a number of different specifications. 相似文献
72.
73.
The effects of patient, hospital, and physician characteristics on length of stay and mortality 总被引:14,自引:0,他引:14
This article compares the ability of hospital and physician characteristics to explain variations in length of stay and mortality, controlling for factors associated with severity of illness. The analysis is based on 54,571 discharges, covering 11 medical and five surgical conditions, from nonfederal general hospitals in one state during 1988. Results suggest that both hospital and physician characteristics are important predictors of both outcome measures. Contrary to previous research, the volume of patients with the same condition treated by the hospital increases both length of stay and mortality. The volume of patients with the same condition treated by the physician increases length of stay among patients with medical conditions, decreases length of stay among those with surgical conditions, and decreases mortality. One interesting finding is that the medical school attended by the physician influences the patient's length of stay. Findings are interpreted in light of research evidence on factors affecting medical outcomes and recent federal efforts to improve quality of care. 相似文献
74.
R Snyder J Bishop G Brodie W Burns A Coates J Levi D Raghavan M Schwarz M Tattersall D Thomson 《Cancer treatment reports》1987,71(3):273-276
Epirubicin was studied in a phase I setting to find the maximum tolerated dose when given weekly for 3 of 4 weeks. Forty-one evaluable patients were treated in groups at doses increasing from 20 to 45 mg/m2. The highest dose level produced the maximum degree of myelosuppression (lowest neutrophil count, 1.9 X 10(9)/L; range, 0-3.7) recorded on Day 22. This was well-tolerated in this group of mainly pretreated patients. Nonhematologic side effects were minimal. This dose schedule allows a greater dose per unit time to be administered than other recommended schedules for epirubicin. 相似文献
75.
On a daily basis, clinicians make decisions regarding therapies to result in the best outcome for their patients. These decisions should be based on the evidence in the literature, indicating a therapy will cause the best outcome. To facilitate this, many professional societies and scientific journals have published technical and scientific reviews, as well as evidence-based standards of care focused on many issues of nutrition support practice. This paper provides an overview of how these reviews and standards of care are derived to promote both the understanding of what they can and cannot do to enhance clinical practice. 相似文献
76.
Patric M Schiltz German G Gomez Susana B Read Nisha V Kulprathipanja Carol A Kruse 《Journal of interferon & cytokine research》2002,22(12):1209-1216
To enhance the efficacy of cellular immunotherapy for gliomas, we tested the concept of using proinflammatory cytokine treatment with interferon-gamma (IFN-gamma) or interleukin-1beta (IL-1beta) or both to render glioma cells more susceptible to cytolysis by alloreactive cytotoxic T lymphocytes (aCTL). The cytokines, separately or in combination, were able to upregulate major histocompatibility complex (MHC) class I antigen or intercellular adhesion molecule-1 (ICAM-1) on Fischer rat 9L gliosarcoma cells. 9L cells were incubated in vitro for 24, 48, or 72 h with varying concentrations of rat IFN-gamma (0-2000 U/ml) or recombinant human IL-1 (rHUIL-1) (0-1000 U/ml) or both. By 48 h, IFN-gamma (500 U/ml) maximally induced the percentage of positive expressing cells and the relative antigen density of MHC class I and ICAM-1 on 9L cells, whereas IL-1 induced only ICAM-1 expression. Simultaneous incubation of IL-1 with IFN-gamma did not further affect the induction of class I on 9L cells more than that achieved with IFN-gamma alone. 9L cells with upregulated MHC class I and ICAM-1 expression were more sensitive to lysis by aCTL in in vitro cytotoxicity assays, regardless of whether the precursor aCTL came from naive or from 9L-immunized rats. Furthermore, inhibition of 9L cytotoxicity in assays that included blocking antibodies to MHC class I or to ICAM-1 revealed that T cell receptor (TCR) interactions with MHC class I and that ICAM-1 interactions with lymphocyte function-associated-1 (LFA-1) antigen account for a portion of the glioma lysis by aCTL. 相似文献
77.
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80.
Brendan M McGuire Herbert L Bonkovsky Robert L Carithers Raymond T Chung Leonard I Goldstein John R Lake Anna S Lok Carol J Potter Elizabeth Rand Michael D Voigt Pamela R Davis Joseph R Bloomer 《Liver transplantation》2005,11(12):1590-1596
In erythropoietic protoporphyria (EPP), there is excessive production of protoporphyrin, primarily in the bone marrow, resulting in increased biliary excretion of this heme precursor. Some patients will develop progressive liver disease that may ultimately require liver transplantation. However, excessive production of protoporphyrin by the bone marrow continues after transplantation, which may cause recurrent disease in the allograft. This study was performed to define post-transplant survival, the risk of recurrent disease, and specific management issues in patients transplanted for EPP liver disease. The patients studied consisted of twelve males and eight females, with an average age of 31 (range, 13-56) years at the time of transplantation. The estimated maximum MELD score prior to transplant was 21 (range, 15-29). Unique complications in the perioperative period were light induced tissue damage in four patients and neuropathy in six, requiring prolonged mechanical ventilation in four. Patient and graft survival rates were 85% at 1 year, 69% at 5 years, and 47% at 10 years. Recurrent EPP liver disease occurred in 11 of 17 patients (65%) who survived more than 2 months. Three patients were retransplanted at 1.8, 12.6, and 14.5 years after the initial transplant for recurrent EPP liver disease. In conclusion, the 5-year patient survival rate in patients transplanted for EPP liver disease is good, but the recurrence of EPP liver disease appears to diminish long term graft and patient survival. 相似文献