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排序方式: 共有923条查询结果,搜索用时 31 毫秒
51.
Rokas Lukosevicius Simonas Juzenas Violeta Salteniene Ugne Kulokiene Justina Arstikyte Georg Hemmrich-Stanisak Andre Franke Alexander Link Paulius Ruzgys Saulius Satkauskas Henrikas Pauzas Tadas Latkauskas Gediminas Kiudelis Francesc Balaguer Juozas Kupcinskas Jurgita Skieceviciene 《International journal of molecular sciences》2022,23(4)
Regulatory changes occurring early in colorectal cancer development remain poorly investigated. Since the majority of cases develop from polyps in the adenoma-carcinoma transition, a search of early molecular features, such as aberrations in miRNA expression occurring prior to cancer development, would enable identification of potentially causal, rather than consequential, candidates in the progression of polyp to cancer. In the current study, by employing small RNA-seq profiling of colon biopsy samples, we described differentially expressed miRNAs and their isoforms in the adenoma-carcinoma transition. Analysis of healthy-adenoma-carcinoma sequence in an independent validation group enabled us to identify early deregulated miRNAs including hsa-miR-1246 and hsa-miR-215-5p, the expressions of which are, respectively, gradually increasing and decreasing. Loss-of-function experiments revealed that inhibition of hsa-miR-1246 lead to reduced cell viability, colony formation, and migration rate, thereby indicating an oncogenic effect of this miRNA in vitro. Subsequent western blot and luciferase reporter assay provided evidence of hsa-miR-1246 being involved in the regulation of target AXIN2 and CFTR genes’ expression. To conclude, the present study revealed possible involvement of hsa-miR-1246 in early colorectal cancer development and regulation of tumor suppressors AXIN2 and CFTR. 相似文献
52.
Michael Mahoney, who made seminal contributions not only to the Society for the Exploration of Psychotherapy Integration (SEPI) but also to the entire field of psychotherapy, died a tragic death at the age of 60 on May 31, 2006. He published more than 250 scholarly articles and chapters, authored and edited 19 books (one of which was awarded a Citation Classic by the Science Citation Index), edited 4 journals, and served on 23 editorial boards plus numerous guest editorships and advisory boards. His research spanned a tremendous breadth without sacrificing depth. Primarily, however, he inquired into development across the life course, including but not limited to psychotherapy. Initially trained as a behaviorist, he played a significant role in the cognitive revolution in psychology; he was also a leading figure in constructivist psychotherapies. He was a Fellow of the World Academy of Art and Science, as well as a Fellow of the American Association for the Advancement of Science. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
This paper proposes an analytical model for line (1D) and point contacts (2D), based upon the Ertel’s hypothesis to predict the evolution of film thickness in steady-state and transient conditions in elastohydrodynamic lubrication. This theoretical approach, applied to a velocity ramp at constant deceleration, is perfectly supported by experimental results in terms of film thickness distribution during the deceleration process and in terms of central film thickness at the vanishing of the entrainment velocity. This work emphasizes the role of the transport effects of the lubricant at the instantaneous entrainment velocity on the time and length scales at which the film thickness disturbances induced by the deceleration process occur until the complete halting of the surfaces. 相似文献
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Andre Valente Bueno José Antonio Velásquez Luiz Fernando Milanez 《Applied Thermal Engineering》2009,29(8-9):1657-1675
This paper presents a new arrangement for the indicating measurement system utilized in the study of internal combustion engines. In this experimental configuration, the current polarized by a piezoelectric pressure transducer is converted into an analog signal proportional to the cylinder pressure variation rate, which constitutes the primary information for combustion heat release analysis. The proposed technique reduces the uncertainty in the pressure derivative data, providing more accurate heat release results than those obtained with the traditional transducer signal conditioning procedure, which requires the numerical derivation of in-cylinder pressure data supplied by a charge amplifier. 相似文献
58.
Tony Minoru Tamura Lopes Andre Augusto Ciré Cid Carvalho de Souza Arnaldo Vieira Moura 《Constraints》2010,15(2):151-189
Brazilian petrobras is one of the world largest oil companies. Recurrently, it faces a very difficult planning and scheduling problem: how to
operate a large pipeline network in order to adequately transport oil derivatives and biofuels from refineries to local markets.
In spite of being more economical and environmentally safer, the use of a complex pipeline network poses serious operational
difficulties related to resource allocation and temporal constraints. The current approaches known from the literature only
consider a few types of constraints and restricted topologies, hence they are far from being applicable to real instances
from petrobras. We propose a hybrid framework based on a two-phase problem decomposition strategy. A novel Constraint Programming (CP) model
plays a key role in modelling operational constraints that are usually overlooked in literature, but that are essential in
order to guarantee viable solutions. The full strategy was implemented and produced very adequate results when tested over
large real instances. 相似文献
59.
Robert Schafranek Andre Giere Adam G. Balogh Thorsten Enz Yuliang Zheng Patrick Scheele Rolf Jakoby Andreas Klein 《Journal of the European Ceramic Society》2009,29(8):1433-1442
Barium strontium titanate (BST) thin films are studied with respect to their application as tunable dielectric at microwave frequencies. BST thin films are deposited by means of radio-frequency magnetron sputtering on platinized Si substrates. The substrate to target distance during sputter deposition is varied and the effect on structure, topology, composition and electronic properties is monitored using X-ray diffraction, atomic force microscopy, Rutherford backscattering spectrometry and X-ray photoelectron spectroscopy. These findings are related to the dielectric measurements, which are carried out at 1 MHz and in the microwave range up to 8 GHz using metal-insulator-metal structures with Pt electrodes. For further device evaluation, leakage current measurements are carried out. Changing the process parameter strongly affects the composition of the films. The results emphasize the possibility for enhancing the microwave properties by fine-tuning of the chosen process parameter. 相似文献
60.
The presence of thermally induced residual stresses, created during the industrial direct chill (DC) casting process of aluminum
alloys, can cause both significant safety concerns and the formation of defects during downstream processing. Although numerical
models have been previously developed to compute these residual stresses, most of the computations have been validated only
against measured surface distortions. Recently, the variation in residual elastic strains in the steady-state regime of casting
has been measured as a function of radial position using neutron diffraction (ND) in an AA6063 grain-refined cylindrical billet.
In the present study, these measurements are used to show that a well-designed thermomechanical finite element (FE) process
model can reproduce relatively well the experimental results. A sensitivity analysis is then carried out to determine the
relative effect of the various mechanical parameters when computing the as-cast residual stresses in a cylindrical billet.
Two model parameters have been investigated: the temperature when the alloy starts to thermally contract and the plasticity
behavior. It is shown that the mechanical properties at low temperatures have a much larger influence on the residual stresses
than those at high temperatures. 相似文献