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排序方式: 共有274条查询结果,搜索用时 11 毫秒
271.
Karen Broekhuizen M.Sc. Willemieke Kroeze Ph.D. Mireille NM van Poppel Ph.D. Anke Oenema Ph.D. Johannes Brug Ph.D. 《Annals of behavioral medicine》2012,44(2):259-286
Background
A review update is necessary to document evidence regarding the effectiveness of computer-tailored physical activity and nutrition education.Purpose
The purpose of this study was to summarize the latest evidence on the effectiveness of computer-tailored physical activity and nutrition education, and to compare the results to the 2006 review.Methods
Databases were searched for randomized controlled trials evaluating computer-tailored physical activity and nutrition education aimed at primary prevention in adults, published from September 2004 through June 2011.Results
Compared to the findings in 2006, a larger proportion of studies found positive effects for computer-tailored programs compared to generic or no information, including those for physical activity promotion. Effect sizes were small and generally at short- or medium-term follow-up.Conclusions
The results of the 2006 review were confirmed and reinforced. Future interventions should focus on establishing larger effect sizes and sustained effects and include more generic health education control groups and objective measurements of dietary behavior. 相似文献272.
Rob NM Weijers 《World journal of diabetes》2022,13(3):275-277
Xu et al used the HOMA2 model to estimate the β-cell function and insulin resistance levels in an individual from simultaneously measured fasting plasma glucose and fasting plasma insulin levels. This method is based on the assumption that the glucose-insulin axis is central for the metabolic activities, which led to type 2 diabetes. However, significant downregulation of both the NKX2-1 gene and the TPD52L3 gene force an increase in the release of free fatty acids (FFAs) into the blood circulation, which leads to a marked reduction in membrane flexibility. These data favor a FFA-glucose-insulin axis. The authors are invited to extend their study with the introduction of the saturation index (number of carbon-carbon double bonds per 100 fatty-acyl chains), as observed in eryth rocytes. 相似文献
273.
Fiona Heeman Denise Visser Maqsood Yaqub Sander Verfaillie Tessa Timmers Yolande AL Pijnenburg Wiesje M van der Flier Bart NM van Berckel Ronald Boellaard Adriaan A Lammertsma Sandeep SV Golla 《Journal of cerebral blood flow and metabolism》2023,43(3):369
Alzheimer’s disease is characterized by regional reductions in cerebral blood flow (CBF). Although the gold standard for measuring CBF is [15O]H2O PET, proxies of relative CBF, derived from the early distribution phase of amyloid and tau tracers, have gained attention. The present study assessed precision of [15O]H2O derived relative and absolute CBF, and compared precision of these measures with that of (relative) CBF proxies. Dynamic [15O]H2O, [18F]florbetapir and [18F]flortaucipir PET test-retest (TrT) datasets with eleven, nine and fourteen subjects, respectively, were included. Analyses were performed using an arterial input model and/or a simplified reference tissue model, depending on the data available. Relative CBF values (i.e. K1/K1′ and/or R1) were obtained using cerebellar cortex as reference tissue and TrT repeatability (i.e. precision) was calculated and compared between tracers, parameters and clinical groups. Relative CBF had significantly better TrT repeatability than absolute CBF derived from [15O]H2O (r = −0.53), while best TrT repeatability was observed for [18F]florbetapir and [18F]flortaucipir R1 (r = −0.23, r = −0.33). Furthermore, only R1 showed, better TrT repeatability for cognitively normal individuals. High precision of CBF proxies could be due to a compensatory effect of the extraction fraction, although changes in extraction fraction could also bias these proxies, but not the gold standard. 相似文献
274.
Ben M Eyck Maurice PHM Jansen Bo Jan Noordman Peggy N Atmodimedjo Berend J van der Wilk John WM Martens Jean A Helmijr Corine M Beaufort Bianca Mostert Michail Doukas Bas PL Wijnhoven Sjoerd M Lagarde J Jan B van Lanschot Winand NM Dinjens 《The Journal of pathology》2023,259(1):35-45
Active surveillance instead of standard surgery after neoadjuvant chemoradiotherapy (nCRT) has been proposed for patients with oesophageal cancer. Circulating tumour DNA (ctDNA) may be used to facilitate selection of patients for surgery. We show that detection of ctDNA after nCRT seems highly suggestive of major residual disease. Tumour biopsies and blood samples were taken before, and 6 and 12 weeks after, nCRT. Biopsies were analysed with regular targeted next-generation sequencing (NGS). Circulating cell-free DNA (cfDNA) was analysed using targeted NGS with unique molecular identifiers and digital polymerase chain reaction. cfDNA mutations matching pre-treatment biopsy mutations confirmed the presence of ctDNA. In total, 31 patients were included, of whom 24 had a biopsy mutation that was potentially detectable in cfDNA (77%). Pre-treatment ctDNA was detected in nine of 24 patients (38%), four of whom had incurable disease progression before surgery. Pre-treatment ctDNA detection had a sensitivity of 47% (95% CI 24–71) (8/17), specificity of 85% (95% CI 42–99) (6/7), positive predictive value (PPV) of 89% (95% CI 51–99) (8/9), and negative predictive value (NPV) of 40% (95% CI 17–67) (6/15) for detecting major residual disease (>10% residue in the resection specimen or progression before surgery). After nCRT, ctDNA was detected in three patients, two of whom had disease progression. Post-nCRT ctDNA detection had a sensitivity of 21% (95% CI 6–51) (3/14), specificity of 100% (95% CI 56–100) (7/7), PPV of 100% (95% CI 31–100) (3/3), and NPV of 39% (95% CI 18–64) (7/18) for detecting major residual disease. The addition of ctDNA to the current set of diagnostics did not lead to more patients being clinically identified with residual disease. These results indicate that pre-treatment and post-nCRT ctDNA detection may be useful in identifying patients at high risk of disease progression. The addition of ctDNA analysis to the current set of diagnostic modalities may not improve detection of residual disease after nCRT. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland. 相似文献