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931.
932.
With the advent of Internet-based 24-hour recall (24HR) instruments, it is now possible to envision their use in cohort studies investigating the relation between nutrition and disease. Understanding that all dietary assessment instruments are subject to measurement errors and correcting for them under the assumption that the 24HR is unbiased for usual intake, here the authors simultaneously address precision, power, and sample size under the following 3 conditions: 1) 1-12 24HRs; 2) a single calibrated food frequency questionnaire (FFQ); and 3) a combination of 24HR and FFQ data. Using data from the Eating at America's Table Study (1997-1998), the authors found that 4-6 administrations of the 24HR is optimal for most nutrients and food groups and that combined use of multiple 24HR and FFQ data sometimes provides data superior to use of either method alone, especially for foods that are not regularly consumed. For all food groups but the most rarely consumed, use of 2-4 recalls alone, with or without additional FFQ data, was superior to use of FFQ data alone. Thus, if self-administered automated 24HRs are to be used in cohort studies, 4-6 administrations of the 24HR should be considered along with administration of an FFQ.  相似文献   
933.

Objective

To systematically review the literature on the implementation of e-health to identify: (i) barriers and facilitators to e-health implementation, and (ii) outstanding gaps in research on the subject.

Methods

MEDLINE, EMBASE, CINAHL, PSYCINFO and the Cochrane Library were searched for reviews published between 1 January 1995 and 17 March 2009. Studies had to be systematic reviews, narrative reviews, qualitative metasyntheses or meta-ethnographies of e-health implementation. Abstracts and papers were double screened and data were extracted on country of origin; e-health domain; publication date; aims and methods; databases searched; inclusion and exclusion criteria and number of papers included. Data were analysed qualitatively using normalization process theory as an explanatory coding framework.

Findings

Inclusion criteria were met by 37 papers; 20 had been published between 1995 and 2007 and 17 between 2008 and 2009. Methodological quality was poor: 19 papers did not specify the inclusion and exclusion criteria and 13 did not indicate the precise number of articles screened. The use of normalization process theory as a conceptual framework revealed that relatively little attention was paid to: (i) work directed at making sense of e-health systems, specifying their purposes and benefits, establishing their value to users and planning their implementation; (ii) factors promoting or inhibiting engagement and participation; (iii) effects on roles and responsibilities; (iv) risk management, and (v) ways in which implementation processes might be reconfigured by user-produced knowledge.

Conclusion

The published literature focused on organizational issues, neglecting the wider social framework that must be considered when introducing new technologies.  相似文献   
934.
935.
936.
The aim of this paper is to identify social and cultural aspects of alcohol consumption in a sample of older people living in their own homes, in eight different European countries. We explore several aspects of alcohol consumption, establishing comparisons between genders, age groups and living circumstances. The phenomenon of alcohol consumption within these countries and cultures is compared in order to gain a better understanding of similarities and differences. Maria Daniel Vaz de Almeida PhD belongs to the Faculty of Nutrition and Food Sciences (FCNAUP), where she is the Head of the Faculty and Professor of Community Nutrition. She has been involved in several European research projects in nutrition and public health. Kate Davidson PhD is a co-director of the Centre for Research on Ageing and Gender (CRAG) at the Sociology Department at the University of Surrey. CRAG brings together social scientific expertise to conduct policy relevant research on gender and ageing. The principal aim is to advance understanding of how gender influences the experience of ageing, and how ageing influences gender roles and relationships across the life course.  相似文献   
937.
Combination immunosuppressive therapy, particularly in renal transplant recipients, is associated with a higher than expected risk of development of Kaposi's sarcoma. In this report, cutaneous dissemination of Kaposi's sarcoma occurred in a patient with temporal arteritis who was treated with corticosteroids. Reduction of the steroid dosage was followed by regression of the tumor. This sequence of events suggests a causal relationship between the evolution of the sarcoma and corticosteroid therapy. Although Kaposi's sarcoma may complicate corticosteroid therapy alone, the incidence is considerably lower than in renal transplant recipients receiving combination immunosuppressive therapy. Considering the large number of patients with temporal arteritis who are treated with steroids and that this is the first report of its association with Kaposi's sarcoma, it seems that other factors, perhaps genetic, might be important in the development of this neoplasm.  相似文献   
938.
OBJECTIVE: Although studies have suggested that human cartilage (HC) gp-39 may be an antigen recognized by autoreactive CD4(+) T cells in rheumatoid arthritis, we previously failed to identify specific CD4(+) T cells in patients' synovial fluid or blood using a class II major histocompatibility complex-peptide tetramer composed of the immunodominant HC gp-39(263-275) epitope covalently linked to DR4. We undertook this study to better understand the parameters for specific binding of this tetramer. METHODS: DR4-transgenic mice were immunized with the HC gp-39 peptide, and a set of peptide-responsive hybridomas was derived. Hybridomas were stained with the DR4-gp-39 tetramer and cultured with increasing amounts of peptide in the presence of DR4-expressing antigen-presenting cells to determine functional avidity. RESULTS: Great variability was apparent in the ability of the tetramer to stain the hybridomas, and there was a strong correlation between the intensity of tetramer staining and functional avidity. Importantly, nearly 30% of the hybridomas did not stain with tetramer, and these cells exhibited relatively low functional avidity. Although the addition of an anti-T cell receptor (anti-TCR) monoclonal antibody during the staining procedure enhanced binding of the tetramer to a number of the hybridomas, a significant percentage remained unstainable. Analysis of TCR expression showed that >90% of the hybridomas expressed the same TCR beta-chain variable region (V(beta)10), and sequencing of the TCR junctional regions showed diversity in the third complementarity-determining region. CONCLUSION: These results suggest that immune responses dominated by relatively low-affinity TCR interactions, such as those that may occur in autoimmune disease, will be difficult to detect using standard tetramer techniques.  相似文献   
939.
940.
The glucose-6-phosphate dehydrogenase (G-6-PD) gene is located on the X-chromosome. Normal males have a single gene and produce a single G-6-PD type, while normal XX females may be heterozygotes for two different G-6-PD genes. We report the case of a phenotypic male who was found to be heterozygous for two G-6-PD enzymes. Cytogenetic analysis showed that he was a 46,XX male.  相似文献   
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