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671.
672.
OBJECTIVE: To assess the relationship between ethnicity and decision-makers expressing healthcare wishes in a group of frail older persons enrolled in the Program of All-inclusive Care for the Elderly (PACE). DESIGN: A retrospective chart review of 1193 participants in the PACE program. SETTING: Program of All-inclusive Care for the Elderly, a comprehensive managed care demonstration program serving frail older participants at 10 sites across the nation. PARTICIPANTS: A total of 1193 older adults, all of whom met state criteria for nursing home level of care. Three hundred were non-Hispanic whites, 364 were black, 156 were Hispanic, and 288 were Asian. MEASUREMENTS: Demographic characteristics of the patients and the presence or absence of an alternative decision-maker; the characteristics of alternative decision-makers included the relationship to the participant as recorded in the patient's medical record. RESULTS: Ninety-one percent of white patients expressed their own healthcare wishes in contrast to only 85% of Hispanic, 83% of Asian, and 67% of black patients. An alternative decision-maker was identified for about 15% of Asians and Hispanics and for one-third of blacks, but only about 8% of whites had an alternative decision-maker. Black and Hispanic patients were most likely to have a daughter as an alternative decision-maker, Asians were most likely to have a son, and whites patients were most likely to have a spouse as an alternative decision-maker. Blacks, particularly black men, were the most likely to have a relative other than a spouse or child as an alternative decision-maker. CONCLUSIONS: In this population, we found significant ethnic variation in the person identified to be the decision-maker in a group of frail older people. Ethnic variation reflected sociodemographic as well as cultural differences. However, there are important limitations to this study, and caution should be used in extrapolating the results to other populations or in attributing the results to ethnicity alone. An awareness of cross-cultural patterns in identified or de facto decision-makers can be significant for healthcare workers when they approach patients and their families about issues surrounding end of life decisions.  相似文献   
673.
Raw materials for the growth of Paratellurite TeO2 single crystal were prepared by oxidizing metallic Te with boiling concentrated nitric acid, and large single crystals of Paratellurite were successfully grown from the melt. Simulation experiments of the crystal pulling demonstrated the fluid-flow conditions in the melt.  相似文献   
674.
As a method of high-bit-rate optical processing, the TM light injection-induced optical polarization bistability using Fabry-Perot type laser diodes has been experimentally demonstrated and theoretically analyzed. In these studies, although switching times less than 1 ns both for switch-up and switch-down have been reported, both of the TE and TM outputs exhibit longitudinal multimode spectra. In practical processing systems, a dynamically stable operation of the polarization switching is considered to be essential. It is the purpose of this paper to present an analytical study of the TM light injection-induced polarization bistability using a λ/4-shifted distributed feedback (DFB) laser model and to describe the detailed picture of the mechanism  相似文献   
675.
A novel method for preparation of immobilized tannin on polyethylene has been suggested. A tannin-containing polymer was prepared by radiation-induced graft polymerization of glycidyl methacrylate onto porous polyethylene, followed by coupling tannin with the produced epoxide group. Reaction conditions for preparing immobilized tannin, such as the reaction temperature, pH, and the molar ratio of tannin to the epoxide group were investigated. The tannin content of the tannin-containing porous polyethylene was 20%, which is approximately equivalent to that of the conventional cellulose-based immobilized tannin. The adsorption isotherm for immobilized tannin and ferrous ion was determined.  相似文献   
676.
Ultrasound energy has been applied to speed up enzymatic hydrolysis processes of mussel tissue in order to determine trace and ultratrace elements (As, Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn). The element releases, by action of three proteases (pepsin, pancreatin, trypsin), lipase, and alpha-amylase, have been evaluated by inductively coupled plasma atomic emission spectrometry. Different variables such as pH, sonication temperature, ionic strength, hydrolysis time, ultrasound frequency, extracting volume, and enzyme mass were simultaneously studied by applying an experimental design approach (Plackett-Burman design and central composite design). Results showed that the hydrolysis time was statistically nonsignificant (confidence interval of 95%) for most of the elements and enzymes, meaning that the hydrolysis procedure can be finished within a 30-60-min range. These hydrolysis times are far shorter than those obtained when using thermostatic cameras, between 12 and 24 h. Statistically significant factors were the ultrasound frequency (the highest metals releasing at high-ultrasound frequency), pH, sonication temperature, and ionic strength. All metals can be extracted using the same operating conditions (pH of 1.0 and sodium chloride at 1.0% for pepsin; pH of 7.5, temperature at 37 degrees C, and 0.4 M potassium dihydrogen phosphate/potassium hydrogen phosphate buffer for amylase; pH of 8.0 and 0.5 M potassium dihydrogen phosphate/potassium hydrogen phosphate buffer for pancreatin; pH of 5.0 and 0.5 M potassium dihydrogen phosphate/potassium hydrogen phosphate buffer for lipase; pH of 8.0 and 0.2 M potassium dihydrogen phosphate/potassium hydrogen phosphate buffer for trypsin). Analytical performances, such as limits of detection and quantification, repeatability of the overall procedure, and accuracy, by analyzing DORM-1, DORM-2, and TORT-1 certified reference materials, were finally assessed for each enzyme.  相似文献   
677.
The cell has a corrugated structure, which is formed by aligned V grooves on both the front and back surfaces. The substrate thickness is reduced to 50 μm while retaining high mechanical strength. This permits ease of handling during the fabrication process and subsequent procedures. This thin substrate promises a very high open-circuit voltage, and the structure is also beneficial to high optical performance. The surface reflectance is reduced in the same manner as that of V-grooved cells, but the optical path is lengthened by a minimum of four times the substrate thickness. Performance of experimental cells is also discussed  相似文献   
678.
Two novel triterpene glycosides, achyranthosides E and F, were isolated as methyl esters from the root of Achyranthes fauriei, an antiinflammatory medicinal plant. Their structures were characterized as oleanolic acid glucuronides having unique substituents composed of C6H9O5 and C9H15O7, respectively, at the C-3 position of glucuronic acid. These compounds are active components which can inhibit the excess recruiting of neutrophiles to injured tissues 1,000 times more potently than sialyl Lewis X.  相似文献   
679.
Characteristics are described of a novel probe sensitive to the amplitude and phase of the radio-frequency magnetic field which is composed of a laser diode linked with a small loop antenna, an optical fiber, and a phase-sensitive detection instrument. The probe is highly sensitive and is radio-frequency interference free. The minimum detectable radio-frequency magnetic field is 10 μA/cm (38 nW/cm2in power density).  相似文献   
680.
STATEMENT OF PROBLEM: Scientific evidence is lacking to support the general application of implant-supported mandibular overdentures. PURPOSE: This randomized clinical trial was undertaken to compare the efficacy of conventional mandibular and implant-supported overdentures in diabetic edentulous patients with clinically acceptable metabolic control. METHOD: A total of 102 diabetic patients, treated with or without insulin, were randomized to receive a new maxillary denture and either a conventional or an implant-supported removable mandibular overdenture. Treatment was completed for 89 patients, 37 with the conventional and 52 with implant-supported dentures. Detailed examinations, tests, and questionnaires were given before and at 6- and 24-months after treatment completion. Comparisons between the two treatment groups were made for treatment failures based on prespecifed criteria and the type and amount of maintenance care provided. RESULTS: The insulin and noninsulin treated groups were collapsed because of the lack of significant differences at entry. The conventional denture and implant-supported overdenture groups were similar in terms of general demographics, medical status, quality of their original dentures and denture support, several functional measures, and patient satisfaction. Treatment was judged to be successful in 56.9% of patients with conventional dentures and 72.1% with overdentures. This difference in success rate was not statistically significant (p > 0.05). Patients with treatment failures in both groups required excessive maintenance care. Those with conventional dentures needed frequent denture base adjustments and relines, whereas those with overdentures required frequent clip replacements and repairs. Although significant improvements were seen with both treatment modalities, a higher percentage of patients with implant-supported overdentures than those with conventional dentures reported improvements in chewing comfort and moderate-to-complete overall satisfaction.  相似文献   
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