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1.
The aim of this clinical study was to evaluate feldspathic ceramic inlays both by clinical criteria and quantitative margin analysis in continuation of an earlier, identically conducted 2-year study. Fifty feldspathic ceramic inlays were adhesively luted in Class II preparations with all margins located in enamel. The inlays were evaluated clinically according to modified USPHS criteria after 3 and 4 years. Quantitative margin analysis was performed with a scanning electron microscope (SEM). Clinically, the inlays showed no recurrent caries and no changes in colour, but superficial marginal discolouration (6%) was apparent after 4 years. Margins were perceptible clinically in 64% of the cases after 4 years. Quantitative margin analysis showed significantly more marginal gaps at the composite/ceramic interface than at the enamel/composite interface. There was neither a significant decrease in perfect margins nor a significant increase in marginal gaps and marginal imperfections at both interfaces between the third and fourth year. Clinically, the inlays performed very well up to 4 years. Clinical evaluation using an explorer only detected substance loss in the cementation gap. The SEM evaluation showed significantly higher changes in marginal qualities during the first 2-year interval of clinical service compared to the second 2-year interval following an exponential mathematical regularity. Quantitative margin analysis should be included in clinical long-term trials to detect early marginal deficiencies at the luting interfaces. Received: 1 September 1997 / Accepted: 31 October 1997  相似文献   
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Extensively burned patients receive iterative blood transfusions and skin allografts that often lead to HLA sensitization, and potentially impede access to vascularized composite allotransplantation (VCA). In this retrospective, single‐center study, anti‐HLA sensitization was measured by single‐antigen‐flow bead analysis in patients with deep, second‐ and third‐degree burns over ≥40% total body surface area (TBSA). Association of HLA sensitization with blood transfusions, skin allografts, and pregnancies was analyzed by bivariate analysis. The eligibility for transplantation was assessed using calculated panel reactive antibodies (cPRA). Twenty‐nine patients aged 32 ± 14 years, including 11 women, presented with a mean burned TBSA of 54 ± 11%. Fifteen patients received skin allografts, comprising those who received cryopreserved (n = 3) or glycerol‐preserved (n = 7) allografts, or both (n = 5). An average 36 ± 13 packed red blood cell (PRBC) units were transfused per patient. In sera samples collected 38 ± 13 months after the burns, all patients except one presented with anti‐HLA antibodies, of which 13 patients (45%) had complement‐fixing antibodies. Eighteen patients (62%) were considered highly sensitized (cPRA≥85%). Cryopreserved, but not glycerol‐preserved skin allografts, history of pregnancy, and number of PRBC units were associated with HLA sensitization. Extensively burned patients may become highly HLA sensitized during acute care and hence not qualify for VCA. Alternatives to skin allografts might help preserve their later access to VCA.  相似文献   
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OBJECTIVE: To evaluate the impact of a newly appointed neurointensivist on neurosciences intensive care unit (NICU) patient outcomes and quality of care variables. DESIGN: Observational cohort with historical controls. SETTING: Ten-bed neurointensive care unit in tertiary university hospital. PATIENTS: Mortality, length of stay (LOS), and discharge disposition of all patients admitted to the NICU were compared between two 19-month periods, before and after the appointment of a neurointensivist. Data regarding these patients were collected using the hospital database and the University Hospitals Consortium database. Individual patient medical records were reviewed for major complications and important prognostic variable documentation. INTERVENTIONS: Appointment of a neurointensivist. MEASUREMENTS AND MAIN RESULTS: We analyzed 1,087 patients before and 1,279 after the neurointensivist's appointment. The unadjusted in-hospital mortality decreased from 10.1% in the before to 9.1% in the after period (95% confidence interval, -1.3 to 3%, relative mortality reduction of 9.9%), but this decrease was significantly different than the expected increase of 1.4% in University Hospitals Consortium mortality during the same period (p = .048). The unadjusted mortality in the NICU decreased from 8% to 6.3% (95% confidence interval, -0.5 to 4, relative mortality reduction 21%) and mean NICU LOS from 3.5 to 2.9 days (95% confidence interval, 0.2 to 0.9, relative NICU LOS reduction 17%). A significant 42% reduction of the risk of death during the first 3 days of NICU admission (p = .003) and a 12% greater risk for NICU discharge (p = .02) were found in the after period in multivariate proportional hazard models. Discharge home increased from 51.7% in the before to 59.7% in the after period (95% confidence interval, 4 to 12, relative increase of 15%) and discharge to a nursing home decreased from 8.1% to 6.8% (95% confidence interval, -1 to 4, relative decrease of 16%). Although a higher total number of complications occurred in the after period, fewer of them occurred in the NICU (odds ratio, 0.2; 95% confidence interval, 0.08 to 0.54, p = .001); this may possibly be due to the better documentation by the NICU team in the after period. CONCLUSIONS: The institution of a neurointensivist-led team model was associated with an independent positive impact on patient outcomes, including a lower intensive care unit mortality, LOS, and discharge to a skilled nursing facility and a higher discharge home.  相似文献   
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A biphasic increase of putrescine concentration occurs in rat hepatoma tissue culture cells induced to proliferate. DL-alpha-Methyl ornithine, a competitive inhibitor of ornithine decarboxylase ( L-ornithine carboxylyase, EC 4.1.1.7) of hepatoma tissue culture cells, blocks the usual increases of putrescine and spermidine concentrations in these cells, and causes a rapid fall in the levels of putrescine which is followed by a striking decrease of spermidine.In parallel with the depletion of these amines, incorporation of [3H]thymidine into DNA and cell proliferation are inhibited. Addition of putrescine, spermidine, or spermine results in an immediate resumption of cell proliferation. Cell proliferation is also restored by L-ornithine presumably due to in situ competitive inhibition of ornithine decarboxylase. These findings of hepatoma tissue culture cells support the concept that polyamines play an essential function in the cell division processes.  相似文献   
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Many articles have been published on the subject of FNAFNA, highlighting the usefulness of flow cytometry in the diagnosis and classification of lymphomas. But occasionally, flow cytometric evaluation fails to detect an abnormal population in a FNAFNA specimen involved by lymphoid neoplasm. Sampling errors (poor viability, peripheral blood contamination and hypocellular specimens) are the major reasons of this failure. In our laboratory we use a simple, fast and cost-effective approach to assess adequacy of FNAFNA materials and in this paper, we describe this procedure with giving some examples of interpretations of our results.  相似文献   
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From January, 1977, through December 1983, 62 patients with thyroid edematous ophthalmopathy were given external orbital radiotherapy according to S.S. Donaldson's technique: 5,5 MV photons produced by a linear accelerator were used to irradiate the muscular conus, with a total of 20 grays in 10 sessions over 2 weeks. Good results were obtained in 46 patients (77%). This simple therapy may be a first choice in recent ophthalmopathy.  相似文献   
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Severe burned patients need definitive and efficient wound coverage. Outcome of massive burns has been improved by using cultured epithelial autografts (CEA). Despite fragility, percentages of success take, cost of treatment and long-term tendency to contracture, this surgical technique has been developed in few burn centres. First improvements were to combine CEA and dermis-like substitute. Cultured skin substitutes provide earlier skin closure and satisfying functional result. These methods have been used successfully in massive burns. Second improvement was to allow skin regeneration by using epidermal stem cells. Stem cells have capacity to differentiate into keratinocytes, to promote wound repair and to regenerate skin appendages. Human mesenchymal stem cells contribute to wound healing and were evaluated in cutaneous radiation syndrome. Skin regeneration and tissue engineering methods remain a complex challenge and offer the possibility of new treatment for injured and burned patients.  相似文献   
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