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991.
OBJECTIVES: This research studied the correlates of health insurance status among three major subpopulations (Mexican, Puerto Rican, and Cuban) of adult (ages of 20 to 64) Latino women. METHODS: Data from the Hispanic Health and Nutrition Examination Survey (HHANES), 1982-1984, were examined to determine the percentages of health insurance coverage among the sample populations and to assess the relationship between access to coverage and selected sociodemographic employment/income, ancestry, and acculturation variables. RESULTS: Variations in health insurance coverage existed by Latina subpopulation. While Puerto Rican women had the highest percentage of any health insurance coverage, Mexican-origin women (particularly those 50 to 64 years old) had the lowest. For all three Latina groups, health insurance coverage was greater among those who reported a family income above the poverty level than among those whose income fell below the poverty level; employment location, acculturation variables, and ancestry were also related to coverage. CONCLUSIONS: Eligibility requirements, particularly for Mexican-and Cuban-origin women, need to be streamlined, and innovative health insurance programs need to be developed to increase access of Latinas to health insurance.  相似文献   
992.
OBJECTIVE: to determine the societal cost-effectiveness of various management strategies, including both the diagnostic imaging work-up and treatment, for patients with intermittent claudication in The Netherlands. METHODS: a decision-analytic model was used and included probability and quality of life data available from the literature. A cost-analysis was performed in a university setting in The Netherlands. Imaging work-up options included magnetic resonance angiography (MRA), color-guided duplex ultrasound, or intraarterial digital subtraction angiography (DSA) and treatment options were percutaneous transluminal angioplasty with selective stent placement if feasible or bypass surgery. Management strategies were defined as combinations of imaging work-up and treatment options. A conservative strategy with no imaging work-up and walking exercises was considered as reference. Main outcome measures were quality-adjusted life years (QALYs), lifetime costs (euro), and incremental cost-effectiveness (CE) ratios. The base-case analysis evaluated 60-year-old men with severe unilateral intermittent claudication of at least one year duration. RESULTS: the range in QALYs and costs across management strategies that considered angioplasty as only treatment option was small (maximum difference: 0.0033 QALYs and 451 euros). Similarly, the range was small across management strategies that considered angioplasty if feasible otherwise bypass surgery (maximum difference: 0.0033 QALYs and 280 euros). MRA in combination with angioplasty (6.1487 QALYs and 8556 euros) had a CE ratio of 20,000 euros/QALY relative to the conservative strategy. The most effective strategy was DSA in combination with angioplasty if feasible otherwise bypass surgery (6.2254 QALYs and 18,583 euros) which had a CE ratio of 131,000 euros/QALY relative to MRA in combination with angioplasty. CONCLUSION: the results suggest that the imaging work-up with non-invasive imaging modalities can replace DSA for the work-up of patients with intermittent claudication without a substantial loss in effectiveness and a minimal cost-reduction. Management strategies including angioplasty are cost-effective in the Netherlands but although strategies including bypass surgery are more effective, their incremental costs are very high.  相似文献   
993.
Shear bond strength of five porcelain repair systems on cerec porcelain.   总被引:2,自引:0,他引:2  
P J van der Vyver  F A de Wet  S J Botha 《SADJ》2005,60(5):196-8, 200; quiz 216, 218
The purpose of this in vitro investigation was to evaluate the shear bond strength of composite resin bonded to Cerec Vitablocs Mark II porcelain with four different porcelain repair systems. The systems evaluated in this study were Scotchbond/ RelyX Primer (S/ 3M), Ultradent Porcelain Repair Kit (U, Ultradent), Vivadent Ceramic Repair Kit (V, Vivadent) and Prime & Bond NT/ Calibra Silane Coupling Agent (P, Dentsply). Seventy five Cerec Vitablocks Mark II porcelain were embedded in metal rings, leaving 7 mm of porcelain exposed above the ring surface. Samples were ground wet on 400 grit SiC paper to roughen the surface and then screened for surface defects. The five porcelain repair agents were applied according to manufacturers' instructions and matching composite stubbs, then bonded onto 15 treated porcelain surfaces, using an Ultradent mould with a diameter of 2,38 mm. All samples were stored in distilled water for 24 hours at 37 degrees C before the bonds were stressed to failure, using a shear load in a Texture Analyser (TAXT2i) (Stable Micro Systems) Data was analyzed statistically (ANOVA). The effects of the pretreatments on the porcelain surfaces after treatment with the different systems were examined in a Scanning Electron Microscope (SEM), and the modes of fracture were assessed under a light microscope. The mean SBS (MPa) for the products in descending order were: U = 26.6 1.7; V = 20.9 3.4; C = 19.4 5.3; S = 18.0 2.0 and P = 15.9 2.1. The Student-t Test revealed a statistical significant difference (p < 0.05) between the mean shear bond strengths of P and U. There was also a statistical significant difference (p < 0.05) between the mean shear bond strengths of P and V. Most debonded specimens showed cohesive fractures in the porcelain. Significant shear bond strength differences were observed for the different repair systems. All the systems tested can probably be used to repair Cerec Vitablocs Mark II porcelain, with some systems providing higher bond strengths.  相似文献   
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998.
Due to its localisation in the apex of the lung with invasion of the lower part of the brachial plexus, first ribs, vertebrae, subclavian vessels or stellate ganglion, a superior sulcus tumour causes characteristic symptoms, like arm or shoulder pain or Horner's syndrome. If rib invasion is the only feature, lysis of the rib must be evident on the chest radiograph; otherwise the tumour cannot be defined as a Pancoast tumour. It is important to adequately stage the tumour, because staging significantly influences survival. Survival is better for T3 than T4 tumours and mediastinal lymph node involvement has been found to be a negative prognostic factor. Also Horner's syndrome and incompleteness of resection worsen survival. The management of superior sulcus tumours has evolved over the past 50 years. Before 1950 it was considered to be inoperable and uniformly fatal. Shaw and Paulson introduced combined modality treatment and for many years, this combination of radiotherapy and surgery was the treatment of choice with a mean 5-year survival of approximately 30%. Postoperative radiotherapy or brachytherapy does not improve survival in patients with complete or incomplete resection. The tumour can be resected through the classic posterior Shaw-Paulson approach or the newer anterior transcervical approach, introduced by Dartevelle. This method facilitates better exposure of the extreme apex of the lung, brachial plexus and subclavian vessels. Regarding the extent of pulmonary resection, en bloc resection of the involved ribs with a lobectomy is recommended. Recent multimodality studies, involving chemoradiotherapy and surgical resection, show promising results regarding completeness of resection, local recurrence and survival, provided that appropriate staging has been carried out. However, careful patient selection and adequate perioperative management with protection of the bronchial stump or anastomosis are important to achieve reasonable rates of morbidity and mortality. As brain metastases remain one of the most common forms of relapse, further studies are needed to examine the role of prophylactic cranial irradiation in patients with complete resection. Also the addition of other chemotherapy agents or biologic agents such as angiogenesis inhibitors or tyrosine kinase inhibitors gives a new perspective in the treatment of Pancoast tumours.  相似文献   
999.
OBJECTIVE: To evaluate the follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels in early follicular phase throughout the reproductive years. METHOD: FSH and LH concentrations were determined by radioimmunoassay (RIA). Linear and polynomial regressions were carried out considering basal FSH as the dependent and age as the independent variable. RESULTS: FSH levels increased throughout the reproductive years (P<0.025). A positive correlation between age and basal FSH levels was detected (P<0.05). The Pearson squared coefficient of r(2)=0.889 was obtained. Using polynomial regression, the inclination of the parabole (Y=7.97-0.009x+0.057x(2)) was 0.359 and the generalized correlation coefficient was r=0.795. The goodness of fit analysis showed that the parabole may better represent the phenomenon (F=4.7; P<0.05). The LH levels remained constant, increasing only beyond 40 years of age. CONCLUSION: The FSH levels rose in a nonlinear way during the reproductive life and the LH concentrations increased discreetly only in patients over 40 years of age.  相似文献   
1000.
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