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The purpose of this paper is to determine whether dynamic cost shifting occurred among acute care hospitals during the period from the early 1980s to the early 1990s and, if so, whether market factors affected the ability to shift costs. Evidence from this study of California acute care hospitals during three time intervals shows that the hospital did practice dynamic cost shifting, but that their ability to shift costs decreased over time. Surprisingly, hospital competition and HMO penetration did not influence cost shifting. However, increasing HMO penetration (measured as the HMO percentage of hospital discharges) did decrease both net prices and costs for the early part of the study, but later was associated with increases in both.  相似文献   
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OBJECTIVE: To evaluate the diagnostic accuracy and clinical usefulness of high-resolution transvaginal duplex Doppler ultrasound in postpartum and post-abortion patients with excessive hemorrhage who are suspected of having residual trophoblast. METHODS: Forty-eight women with excessive hemorrhage referred for possible residual trophoblastic tissue were evaluated by transvaginal duplex Doppler ultrasonography. Based on two-dimensional imaging, the patients were divided prospectively into groups: women who had an empty uterus with a normal uterine cavity, those with a pure endometrial fluid collection and no echogenic foci, those who had a mixed endometrial fluid collection with foci of echogenicity, and those with intracavitary heterogeneous material with mixed echo patterns of fluid and solid components. In each group, Doppler studies were performed and the resistance index (RI) was calculated. The two-dimensional patterns and Doppler results were correlated with clinical and pathologic follow-up. RESULTS: Twenty-eight subjects had a normal uterine cavity and seven had a pure endometrial fluid collection; all were treated conservatively and none showed later clinical evidence of residual trophoblastic tissue. In 13 women, residual trophoblast was strongly suggested from the images of two-dimensional ultrasonography: Five showed an endometrial fluid collection with some echogenic foci, and eight exhibited intracavitary mixed echogenic material. All underwent curettage, and residual trophoblastic tissue was found in ten of the 13. The mean (+/- standard deviation) RI to flow in the myometrial arteries was 0.54 +/- 0.15 in women without residual trophoblast and 0.35 +/- 0.1 in those with residual trophoblastic tissue (P < .01). CONCLUSION: Our experience suggests that transvaginal duplex Doppler ultrasonography is an effective noninvasive method for evaluating patients with excessive postpartum and post-abortion hemorrhage who are suspected of having residual trophoblastic tissue. Its use enhances the positive preoperative diagnosis of residual trophoblastic tissue and may reduce unnecessary curettage procedures.  相似文献   
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The senior authors' initial experience with primary hybrid hip replacement in patients with osteoarthritis was studied to evaluate the efficacy of the procedure. Hybrid total hip arthroplasty (uncemented Harris-Galante acetabular component and cemented Iowa precoated femoral component) was performed in 131 consecutive, nonselected hips in 118 patients with the diagnosis of primary osteoarthritis. Followup was performed at 8 to 9 years after the procedure. The average age at the time of the procedure was 68 years (range, 45-87 years). There were 50 men (55 hips) and 68 women (76 hips). At final followup 19 patients (22 hips) had died. The femoral component had been revised for aseptic loosening in 8 hips (6.1%). One additional hip showed definite radiographic loosening. Hence, the prevalence of radiographic femoral failure was 6.9% (9 hips). No acetabular component had been revised for aseptic loosening and no acetabular component had migrated. The senior author continues to perform hybrid total hip arthroplasty in all patients with primary osteoarthritis. However, design modifications have been made in the femoral component that is used.  相似文献   
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The present study aims at the role of ferritin in the regulation of syncytiotrophoblast free iron levels. The differentiated cytotrophoblast cell in culture is used as a model for this maternal-fetal interface. Cytotrophoblast cells isolated from term placentae are cultured in iron-poor (Medium 199), iron-depleted [desferrioxamine(DFO)] and iron-supplemented [diferric transferrin (hTF-2Fe), ferric ammonium citrate (FAC)] medium. Distribution and de novo synthesis of isoferritins is studied, together with the cellular iron concentration and the ferritin iron saturation. Compared to ferritin isolated from total placenta, ferritin obtained from villous tissue is enriched with acidic isoforms. This observation is in agreement with measured light (L) to heavy (H) subunit ratios < 1 of de novo synthesized ferritin in cultured cytotrophoblast cells. Neither iron-poor culture medium, nor hTf-2Fe supplemented medium affects the cellular iron or ferritin concentration. FAC increased the cellular ferritin iron saturation and (by synthesis) the acidic isoferritin concentrations. The results strongly suggest, that the term syncytiotrophoblast is able to balance transferrin-mediated iron uptake and iron release. In case of FAC supplementation, the syncytiotrophoblast is unable to keep intracellular iron low, and ferritin synthesis is stimulated. The predominance of acidic ferritins and the preferential synthesis of H subunits can be functionally explained by the established fact that iron incorporation in acidic ferritins is faster due to the presence of ferroxidase centres. Damage by free iron catalysed hydroxyl radical formation is therefore minimized.  相似文献   
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