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81.
MR imaging and musculoskeletal ultrasound are expanding their utility in the assessment of patients with chronic inflammatory arthritis. These imaging techniques, by providing additional and more sensitive information over clinical examination and conventional radiographs, are promising tools for the diagnosis, prognosis and assessment of treatment efficacy in patients with juvenile idiopathic arthritis (JIA). Owing to the peculiarities of the growing skeleton, knowledge of imaging in healthy children is of high priority. A sound understanding of growth-related changes is of foremost value in establishing whether the apparent changes on joint surface reflect real damage or are actually part of normal development. This review explores current evidence and suggests a new workflow for imaging in JIA, in which conventional and modern imaging modalities can be integrated for optimal management.  相似文献   
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In this review, we report the state-of-the-art of polymers in thermoelectricity. Classically, a number of inorganic compounds have been considered as the best thermoelectric materials. Since the prediction of the improvement of the figure of merit by means of electronic confinement in 1993, it has been improved by a factor of 3–4. In the mean time, organic materials, in particular intrinsically conducting polymers, had been considered as competitors of classical thermoelectrics, since their figure of merit has been improved several orders of magnitude in the last few years. We review here the evolution of the figure of merit or the power factor during the last years, and the best candidates to compete with inorganic materials. We also outline the best polymers to substitute classical thermoelectric materials and the advantages they present in comparison with inorganic systems.  相似文献   
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A large, multicentre, retrospective survey of patients with hairy cell leukaemia (HCL) was conducted in France to determine the frequency of second malignancies and to analyse the long‐term effects of the established purine nucleoside analogues (PNAs), cladribine and pentostatin. The survey retrospectively reviewed the medical history of patients and their immediate family, clinical and biological presentation at the time of HCL diagnosis, treatment choice, response to treatment, time to relapse and cause of death. Data were collected for 487 patients with HCL. Of the patients included in the survey, 18% (88/487) had a familial history of cancers, 8% (41/487) presented with malignancies before HCL diagnosis and 10% (48/487) developed second malignancies after HCL was diagnosed. An excess incidence of second malignancies was observed, with a standardized incidence ratio (SIR) of 1·86 (95% confidence interval (CI): 1·34–2·51), with no significant difference between PNAs. For second haematological malignancies alone, the SIR was markedly increased at 5·32 (95% CI: 2·90–8·92). This study highlights the high frequency of cancers in HCL patients and their family members. The frequency of second malignancies is notably increased, particularly for haematological malignancies. The respective role of pentostatin and cladribine in the development of second malignancies is debatable.  相似文献   
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Human cancers display substantial intratumoral genetic heterogeneity, which facilitates tumor survival under changing microenvironmental conditions. Tumor substructure and its effect on disease progression and relapse are incompletely understood. In the present study, a high-throughput method that uses neutral somatic mutations accumulated in individual cells to reconstruct cell lineage trees was applied to hundreds of cells of human acute leukemia harvested from multiple patients at diagnosis and at relapse. The reconstructed cell lineage trees of patients with acute myeloid leukemia showed that leukemia cells at relapse were shallow (divide rarely) compared with cells at diagnosis and were closely related to their stem cell subpopulation, implying that in these instances relapse might have originated from rarely dividing stem cells. In contrast, among patients with acute lymphoid leukemia, no differences in cell depth were observed between diagnosis and relapse. In one case of chronic myeloid leukemia, at blast crisis, most of the cells at relapse were mismatch-repair deficient. In almost all leukemia cases, > 1 lineage was observed at relapse, indicating that diverse mechanisms can promote relapse in the same patient. In conclusion, diverse relapse mechanisms can be observed by systematic reconstruction of cell lineage trees of patients with leukemia.  相似文献   
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