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51.
Changing immunodominance patterns in antiviral CD8 T-cell responses after loss of epitope presentation or chronic antigenic stimulation 总被引:9,自引:0,他引:9
van der Most RG Murali-Krishna K Lanier JG Wherry EJ Puglielli MT Blattman JN Sette A Ahmed R 《Virology》2003,315(1):93-102
The H-2(b)-restricted CD8 T-cell response against lymphocytic choriomeningitis virus is directed against at least 10 dominant and subdominant epitopes, including two newly identified epitopes in the nucleoprotein. We have used this set of epitopes to characterize the plasticity of the hierarchy under different experimental circumstances, i.e., loss of MHC class I molecules, loss of specific epitopes (CTL escape), and prolonged antigenic stimulation (chronic infection). We found that loss of epitope-specific responses was almost inevitably associated with compensatory responses against other, subdominant, epitopes. Multiple epitope loss was required to change the hierarchy. Persistent viral infection was associated with a loss of not only the dominant response against the NP396 epitope, but also a loss of subdominant responses against nucleoprotein epitopes. In contrast, responses against glycoprotein epitopes, dominant and subdominant, survived under chronic infection conditions, and even dominated the response (GP118). Our results suggest that the fate of each specific T-cell response during chronic infection is in part determined by the origin of the cognate epitopes, i.e, the proteins from which they are processed, or, more specifically, nucleoprotein versus glycoprotein. A model in which recruitment time plays a role in the longevity of antiviral T-cell responses during persistent infection is discussed. 相似文献
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The key focus of this longitudinal study in the Netherlands was to determine the role of social support (i.e. perceived availability of emotional support, lack of received problem-focused emotional support, and negative interactions) and positive and negative self-esteem in depressive symptoms in 475 recently diagnosed cancer patients and 255 individuals without cancer from the general population. Patients and the comparison group were interviewed and filled in a questionnaire at two points in time: 3 months (T1) and 15 months (T2) after diagnosis. The results indicated that social support and self-esteem were weakly to moderately related to each other. Negative self-esteem was more strongly related to all three types of social support, compared to positive self-esteem. Regression analyses showed that social support and self-esteem were independently related to depressive symptoms (concurrently), such that lower levels of social support and self-esteem were strongly associated with higher levels of depressive symptoms. This finding suggests that these two resources supplement each other additively. A longitudinal analysis showed that social support and self-esteem also predicted future levels of depressive symptoms, although the explained variance was much lower than in a cross-sectional analysis. Comparisons between cancer patients and the comparison group generally revealed no significant differences between the two groups in the associations of social support and self-esteem with depressive symptoms. The only exception was a lack of problem-focused emotional support. At three months after diagnosis, a lack of this type of support, characterised by reassuring, comforting, problem-solving, and advice, was more strongly related to depressive symptoms in patients than in the comparison group. 相似文献
54.
Bennenbroek FT Buunk BP Stiegelis HE Hagedoorn M Sanderman R Van den Bergh AC Botke G 《Psycho-oncology》2003,12(6):567-579
The present study focused on the effects of social comparison information on subjective understanding of radiation therapy, validation of emotions, and self-efficacy of cancer patients undergoing radiation therapy. The effects of three different audiotapes, containing different kinds of social comparison information, were examined. On the procedural tape a man and woman discussed their illness and radiation treatment, on the emotion tape they focused on the emotional aspects of these issues, and on the coping tape they focused on the way they had been coping. The effects of these tapes were measured on subjective understanding about radiation therapy, validation and recognition of emotions, self-efficacy, and mood. The results indicate positive effects of the tapes, especially of the procedural and the coping tape. These audiotapes increased understanding of radiation therapy, self-efficacy and the feeling of validation of emotions. Therefore, these tapes may be an important supplement to existing patient education information. Possible explanations and practical implications are discussed. 相似文献
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Mirella Minkman Kees Ahaus Robbert Huijsman 《International journal for quality in health care》2007,19(2):90-104
PURPOSE: Health care organizations have to improve their performance for multiple stakeholders and organize integrated care. To facilitate this, various integrated quality management models can be used. This article reviews the literature on the Malcolm Baldrige Quality Award (MBQA) criteria, the European Foundation Quality Management (EFQM) Excellence model (Excellence award models) and the Chronic Care Model. The focus is on the empirical evidence for improved performance by the implementation of interventions based on these models. DATA SOURCES: A systematic literature review from 1995 to May 2006 in the Pubmed, Cochrane, and ABI- databases was conducted. STUDY SELECTION: After selection, 37 studies were included, 16 in the Excellence award model search and 21 in the Chronic Care Model search. DATA EXTRACTION AND RESULTS OF ANALYSIS: Data were retrieved about the main intervention elements, study design, evidence level, setting and context factors, data collection and analysis, principal results and performance dimensions. No Excellence Award model studies with controlled designs were found. For the Chronic Care Model, one systematic review, one meta analysis and six controlled studies were included. Seventeen studies (2 in Excellence award model, 15 in Chronic Care Model) reported one or more significant results. CONCLUSION: There is some evidence that implementing interventions based on the 'evidence-based developed' Chronic Care Model may improve process or outcome performances. The evidence for performance improvement by interventions based on the 'expert-based developed' MBQA criteria and the EFQM Excellence model is more limited. Only a few studies include balanced measures on multiple performance dimensions. Considering the need for integrated care and chronic care improvement, the further development of these models for guiding improvements in integrated care settings and their specific context factors is suggested. 相似文献
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Marlijne E. Ikink Robbert J. Nijenhuis Helena M. Verkooijen Marianne J. Voogt Paul J. H. M. Reuwer Albert J. Smeets Paul N. M. Lohle Maurice A. A. J. van den Bosch 《European radiology》2014,24(10):2649-2657
Purpose
To compare the effectiveness of magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) with that of uterine artery embolisation (UAE) for treatment of uterine fibroids.Methods
Between January 2010 and January 2013, 51 women with symptomatic uterine fibroids underwent MR-HIFU. Follow-up and MR imaging were compared to 68 women treated with UAE, who fulfilled eligibility criteria for MR-HIFU – e.g., size (≤ 12 cm) and number (≤ 5) of fibroids. We compared median symptom severity (tSSS), total health-realted quality of life (HRQoL) scores, and reintervention rates. The adjusted effect on symptom relief and HRQoL improvement was calculated using multivariable linear regression. Cox regression was applied to calculate the adjusted risk of reintervention between both treatments.Results
Median tSSS improved significantly from baseline to three-month follow-up (P?0.001) for both MR-HIFU (53.1 (IQR [40.6-68.8]) to 34.4 (IQR [21.9-46.9]) and UAE (65.3 (IQR [56.3-74.2]) to 21.9 (IQR [9.4-34.4]). In addition, significantly better HRQoL scores were observed after three months (P?0.001). However, in multivariate analysis, UAE had a stronger effect on symptom relief and HRQoL improvement than MR-HIFU (P?0.001). Patients treated with MR-HIFU had a 7.1 (95 % CI [2.00-25.3]; P?=?0.002) times higher risk of reintervention within 12 months (18/51 vs. 3/68).Conclusion
Both MR-HIFU and UAE result in significant symptom relief related to uterine fibroids. However, MR-HIFU is associated with a higher risk of reintervention.Key Points
? This study compared outcomes between volumetric MR-HIFU and UAE for uterine fibroids. ? Both MR-HIFU and UAE result in significant symptom relief and quality of life improvement. ? UAE had a stronger positive effect on the clinical outcomes. ? Reintervention rate after MR-HIFU ablation was significantly higher than after UAE. 相似文献59.
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