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41.
Ultrasound (US) imaging is a well-established diagnostic technique to image soft tissues in real time, while photoacoustic (PA) is an emerging imaging technique employed to collect molecular information. Integration of PA and US imaging provides complementary information enhancing diagnostic accuracy without employing ionizing radiations. The development of contrast agents able to combine PA and US features is pivotal to improve the significance of PAUS imaging and for PAUS-guided treatment of neoplasms. Here, we demonstrate in relevant ex-vivo models that disassembling passion fruit-like nano-architectures (pfNAs) can be employed in PAUS imaging. pfNAs are composed by silica nanocapsules comprising aggregates of commercial NIR-dyes-modified polymers and ultrasmall gold nanoparticles. The intrinsic US and PA features of pfNAs have been fully characterized and validated in tissue-mimicking materials and in ex vivo preparations. Moreover, the application of a multi-parametric approach has allowed the increase of information extrapolated from collected images for a fine texture analysis.  相似文献   
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Resident physicians are continually exposed to fatigue, which can lead to work, academic and personal problems, so it is important to have reliable and valid instruments to measure it. One of the most used is Fatigue Severity Scale, but, there are versions with different number of items in different populations. Therefore, the purpose of this work was to translate, adapt culturally relevant and compare versions with different numbers of items, to identify the most appropriate in Mexican resident physicians. With three different groups of participants; first one for translation by seven expert judges in the language, second for psychometric validation with 100 resident physicians, and third for confirmatory factor analysis and invariance test by type of program (specialty and high specialty) with 182 resident physicians. Distribution, discrimination, reliability and factor structure of the scale were tested in an exploratory and confirmatory analysis, leaving a final scale of 6 items with good fit (X2[9] = 9,39, p = 0,40; CFI = 0,99; RMSEA = 0,02), with a reliability = 0,91 and strict factorial invariance by type of residence program.  相似文献   
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This collaboration briefly reviews the characteristics of professional learning. It pays special attention to the learning that takes place during clinical practices and to the fundamental role of reflection in the construction of knowledge and in the better understanding of the situation of the other (patients, family members, professionals) and oneself. It emphasizes the learning of values and attitudes, which are manifested in behaviors. Finally, it describes the characteristics of learning by role modeling and the influence of hidden curriculum on the development of professional competences.  相似文献   
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Objective

The present study investigated the association of 3′-UTR VNTR and intron 8 VNTR polymorphisms with a time estimation task performance.

Materials and methods

One hundred and eight men in a Brazilian Northeast population (18–32 years old) participated in the experiment. The 3′-UTR VNTR and intron 8 VNTR polymorphisms were associated alone and combined to absolute error (AE) and relative error (RE) in a time estimation task (target duration: 1 s, 4 s, 7 s and 9 s).

Results

We found an association of the behavioral variable with intron 8 VNTR for the time intervals of 1 s and 9 s (p < 0.001) and polymorphisms combinatorial effect for 1 s (p ≤ 0.05).

Conclusion

The intron 8 VNTR polymorphism and the combinatorial effect can modulate the time estimate in the domain of supra seconds, and thus our study indicates a role of the dopamine transporter in the neurobiological areas related to the time intervals judgment.

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This commentary addresses the issue of the classification of sarcomas in the article written by Watson and colleagues published recently in this journal. The article delves into the molecular characterization and distinct phenotypes of some recently described entities (e.g. BCOR-rearranged sarcomas, CIC-fused sarcomas) and describes new groups with common characteristics. This commentary focuses on several questions raised in the article, such as what makes a group of sarcomas become a clinical entity, which should be the main driver of sarcoma classification, how the classification of small round cell sarcomas is expected to evolve and how high-throughput techniques could be applied to sarcoma diagnosis in the short term. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
50.
BK virus is the causative agent of polyomavirus-associated nephropathy, a major cause of kidney transplant failure affecting 1%-10% of recipients. Previous studies that investigated the viral source on the kidney recipient pointed that the donor is implicated in the origin of human polyomavirus BK (BKPyV) infection in recipients, but giving the low genetic variability of BKPyV this subject is still controversial. The aim of this study was to determine if BKPyV replicating in kidney recipients after transplantation is always originated from the donor. Urine and blood samples from 68 pairs of living donors and kidney recipients who underwent renal transplantation from August 2010-September 2011 were screened for BKPyV by real time polymerase chain reaction. Only three recipients presented viremia. When both donors and recipients were BKPyV positive, a larger fragment of VP1 region was obtained and sequenced to determine the level of similarity between them. A phylogenetic tree was built for the 12 pairs of sequences obtained from urine and high level of similarity among all sequences was observed, indicating that homology inferences for donor and recipient viruses must be cautiously interpreted. However, a close inspection on the donor-recipient pairs sequences revealed that 3 of 12 pairs presented considerably different viruses and 4 of 12 presented mixed infection, indicating that the source of BKPyV infection is not exclusively derived from the donor. We report that about 60% of the renal recipients shed BKPyV genetically distinct from the donor, confronting the accepted concept that the donor is the main source of recipients’ infection.  相似文献   
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