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1.
A randomized prospective study was undertaken to compare the electrical performances of three permanent, endocardial, tined pacing leads with different electrode designs--sintered platinum, vitreous carbon, and porous carbon. Ninety-nine patients received one of the leads (S80 31; 423S 32; S100 36). Acute R wave amplitude and ST elevation of the native endocardial electrogram, voltage threshold, impedance, and current flow at four pulse durations (0.25-1.0 msec) were measured. Voltage thresholds were measured noninvasively at each of four pulse durations at 2 days and 1, 3, and 6 months after implantation. No significant differences were found in sensing properties, or current flow at threshold at 0.5 msec pulse duration. The 423S lead had a significantly higher impedance at threshold and both a higher impedance and lower current flow at 5 V. No significant differences in threshold voltages were found between the three leads at any pulse duration, at any of the assessed times after implantation. Six-month thresholds for the S80, 423S, and S100 leads were 1.18 +/- 0.35, 1.17 +/- 0.29, and 1.06 +/- 0.38 V respectively at 0.5 msec pulse duration. Differences between 'high performance' pacing leads need to be of a greater order of magnitude before they can be exploited to give any real clinical advantage to patients.  相似文献   
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Objective To develop and test a quantitative food frequency method for administration by telephone.Design A comparison study of telephone and face-to-face interviews was conducted among a representative sample of the five major ethnic groups in Oahu, Hawaii. Two interviews were administered 4 to 6 months apart by trained interviewers using identical questionnaires and color photographs of food items showing three different portion sizes. The order of the interviewing methods was randomly assigned. The questionnaire included 115 food items selected to estimate 80% or more of usual dietary intakes. Frequencies and quantities of each item consumed during the past year were obtained.Subjects/setting Subjects were recruited from the Health Surveillance Program of the Hawaii State Department of Health and consisted of 167 men and 158 women, aged 45 to 74 years, who provided a telephone number. Eighty percent of the face-to-face interviews were conducted in the subjects’ homes and 20% were conducted at the workplace or the University of Hawaii Cancer Research Center, if requested.Statistical analyses The paired t test was used to compare the mean daily intakes obtained by the telephone and face-to-face methods. Agreement was measured by the intraclass correlation coefficient (ICC), Pearson correlation coefficient, and weighted κ statistic.Results The means of energy and each nutrient were slightly higher in the first interview than the second, regardless of the interviewing method. Because of close correspondence among all 3 statistical measures of agreement, only the ICCs are reported. The ICCs ranged from .61 for protein and vitamin A to .69 for dietary cholesterol among men, and from .61 for vitamin C to .74 for saturated fat among women. Agreement was not significantly affected by age, gender, ethnicity, order of interview, or educational level.Applications Telephone interviews to obtain quantitative food frequencies are cost-efficient methods for estimating usual dietary intakes among persons in widely scattered geographic areas. Photographs of the foods in 3 portion sizes mailed in advance help the respondents estimate amounts eaten. J Am Diet Assoc. 1998;98:44-48.  相似文献   
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Prior research indicates that alcohol-related outcome expectancies represent important etiological factors in the understanding of alcohol use/abuse. Although current multidimensional measures assess several substantively different domains of alcohol-related outcome expectancies, there is growing evidence that they may not possess adequate levels of discriminant validity. Therefore, the present study sought to examine whether reliable between-person differences exist in the ability to differentiate among alcohol expectancy domains. The focus of the study was on three sets of intrapersonal characteristics: cognitive resources, cognitive constraints, and alcohol-related experience. Data were collected via household interviews with a random sample of 1125 adults. Multiple regression analysis revealed that higher levels of cognitive resources were associated with increasing levels of differentiation among alcohol expectancy domains. Results are discussed in terms of implications for the development of new or revised multidimensional alcohol expectancy questionnaires. Directions for future research are also discussed.  相似文献   
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A guide for providing a continuum of care for children in need of psychiatric services from the least restrictive services (outpatient care), to a moderately restrictive setting (partial hospitalization), to the most restrictive setting (inpatient care) is described. Movement along the continuum is facilitated by the nurse case manager. Concepts from three theoretical frameworks are integrated to define goals, criteria, and expected outcomes for each level of care along the continuum. They are Neuman's (1982) systems model for nursing practice and education, Caplan's (1961) model for primary prevention of mental disorders in children, and Frances, Clarken and Perry's (1984) differential therapeutics. The continuum provides a guide for nurses and other health care providers to achieve high quality care as economically as possible. It also enhances self-care and self-responsibility for families of disturbed children by offering a sequential graded system of care along the health-illness continuum.  相似文献   
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Isotypejsubclass-specific antibody responses to adult Onchocerca volvulus extract (OvAg) were assessed by both ELISA and immunoblotting for a group of putatively immune individuals (PIs, n = 29) from a hyperendemic area in Ecuador and for a group of infected individuals (INFs, n = 47) from the same region. As a group, the Pis have been previously shown to possess lower levels of OvAg specific IgG1, IgG2, IgG3 and IgG4 than INFs but semiquantitative analysis revealed that the relative proportions of these subclasses differs between the two groups. The IgG of the PI group contained a higher proportion of IgG3 and a lower proportion of IgG4 than the INF group. The frequency distribution of IgG3 responses was similar for the PI and INF groups. The frequency distributions for IgG1, IgG4 and IgE were significantly different between the PI and INF groups. A subgroup of the Pis were identified from frequency distributions and multivariate plots of individual isotype responses as having antibody responses (mainly IgG4) possibly indicative of cryptic infection. High IgE responses were exclusive to INF individuals, and a rare response type of high IgG3 with negligible levels of other isotypes/subclasses was seen only in the PI group. However, the majority of the Pis had negligible responses for all antibody classes. Immunoblots demonstrated no obvious differences in qualitative recognition between the PIs and INFs.  相似文献   
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Many rashes have been attributed to thiouracil therapy, but severe vasculitis is rare. A distinct pattern of cutaneous vasculitis affecting limbs, face and ears has been described with propylthiouracil, and is particularly associated with treatment of more than 18 months duration. A positive Antinuclear Antibody (ANA) in the absence of LE cells is often demonstrated. We describe the first such case due to methylthiouracil therapy, the bullous haemorrhagic rash having the histology of pyoderma gangrenosum, and we review the available literature regarding this pattern of vasculitis.  相似文献   
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