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排序方式: 共有247条查询结果,搜索用时 203 毫秒
1.
Marco Bocchetti Maria Grazia Ferraro Filippo Ricciardiello Alessandro Ottaiano Amalia Luce Alessia Maria Cossu Marianna Scrima Wing-Yan Leung Marianna Abate Paola Stiuso Michele Caraglia Silvia Zappavigna Tung On Yau 《International journal of molecular sciences》2021,22(8)
Colorectal cancer (CRC) is the third most deadly cancer worldwide, and inflammatory bowel disease (IBD) is one of the critical factors in CRC carcinogenesis. IBD is responsible for an unphysiological and sustained chronic inflammation environment favoring the transformation. MicroRNAs (miRNAs) belong to a class of highly conserved short single-stranded segments (18–25 nucleotides) non-coding RNA and have been extensively discussed in both CRC and IBD. However, the role of miRNAs in the development of colitis-associated CRC (CAC) is less clear. The aim of this review is to summarize the major upregulated (miR-18a, miR-19a, miR-21, miR-31, miR-155 and miR-214) and downregulated (miR-124, miR-193a-3p and miR-139-5p) miRNAs in CAC, and their roles in genes’ expression modulation in chronic colonic-inflammation-induced carcinogenesis, including programmed cell-death pathways. These miRNAs dysregulation could be applied for early CAC diagnosis, to predict therapy efficacy and for precision treatment. 相似文献
2.
本文利用现场同步加速X-射线衍射、等温量热仪和膨胀测量等手段,研究了在20℃,100%相对湿度下,由25%(重量比)的铝酸钙水泥、12.5%的硅酸盐水泥、12.5%的β-半水石膏和50%的水组成的浆体的水化。水化伊始,首先形成了石膏和钙矾石,同时半水石膏也相应消耗(0-45min内)。随后石膏继续消耗,钙矾石持续形成,2h45min后石膏消耗完毕,铝酸盐-AFm开始形成,同时钙矾石的数量在7h内保持不变。热曲线的第一个峰源自机械搅拌、初始润湿和溶解,还有钙矾石和石膏的形成,第二个峰为石膏被钙矾石所替代,第三个对应于铝酸盐-AFm的形成。石膏被钙矾石替代伴随着0.7%平均线性膨胀。 相似文献
3.
Sai On Cheung Chi Ming Tam Vivian Tam Kevin Cheung Henry Suen 《Construction Management & Economics》2013,31(9):927-935
In response to the increasing public concern over the effects of construction waste on the environment, a performance assessment system has been designed to provide an instant, online assessment of how well a construction site performs environmentally, e.g. measuring the level of pollution generated from a construction site. Through the use of both Internet and database technologies, it is possible to collect and present data that are essential for environmental management online. To achieve this, a set of environmental performance parameters was derived through a postal questionnaire survey and interviews with experts in the field. A conceptual framework was developed, of which the key components were: template, knowledge base, output data and benchmark group. In combination, these factors provide a system that enables speedy assessment and effective management of environmental performance on construction sites, hence prompt decisions can be made and corrective actions can be taken before potential hazards turn into real disasters. 相似文献
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In this study, we aimed to provide important information about the potential economic benefits and risks of nuclear electricity generation associated with existing and prevailing nuclear technologies and to examine the economic effects of nuclear fuel cycle strategies in Korea. An economic analysis model that evaluates the overall life‐cycle costs of nuclear energy systems coupled with multiple fuel cycle options was specially developed by using the levelized cost of electricity (LCOE) as the fundamental methodology. This model is capable of identifying a range of techno‐economic uncertainties underlying each individual nuclear energy system taking into account the state of the art in fuel cycle technologies. It can also quantify and incorporate the resulting impacts into a system‐wide LCOE distribution for each fuel cycle option based on Monte Carlo probabilistic simulation. We analyzed and discussed examples of the economic performance of 13 promising candidates for nuclear energy systems integrated with extensive fuel cycle technologies (including one direct disposal and 12 specific reprocessing and recycling fuel cycle options). We also conducted a sensitivity analysis to investigate the major sensitivity factors of the system component cost in each fuel cycle option and their impacts on individual economic performances. Furthermore, a closer look at the techno‐economic uncertainties of advanced fuel cycle technologies in a break‐even analysis offers evidence of the potential economic feasibility and cost‐reduction opportunities in the reprocessing and recycling options relative to the direct disposal of spent nuclear fuel. 相似文献
6.
Mark Tsun On Wong 《Housing Studies》2019,34(1):1-23
This paper critically discusses the concept of intergenerational family support in housing for young people. Recognizing increased difficulties faced by the younger generation in the housing market, this paper highlights that support from older family members is increasingly important. Nonetheless, it is critiqued that the role of the family home has been largely ignored in the current ‘generation rent’ discourse. By drawing on recent youth studies debates, this paper argues living in the family home could be an important form of support in housing, especially for marginalized youth. This paper presents insights from qualitative studies in Hong Kong and Scotland and analyses interview accounts of socially disengaged young people. It reflects how remaining at the family home could be interpreted as intergenerational support, and further elicits complexities in expectations, negotiations and emotions involved. This analysis offers new evidence and a more nuanced perspective of intergenerational family support in housing research. 相似文献
7.
Effects of pineapple pomace fibre on physicochemical properties of composite flour and dough,and consumer acceptance of fibre‐enriched wheat bread 下载免费PDF全文
Phantipha Chareonthaikij Tanat Uan‐On Witoon Prinyawiwatkul 《International Journal of Food Science & Technology》2016,51(5):1120-1129
Pineapple pomace fibre (PF, containing 70.2% total dietary fibre) can be added to increase dietary fibre of wheat bread. This study was performed to evaluate effects of PF added at 0, 5 or 10% (wheat flour‐basis) on physicochemical properties of the composite flour (wheat flour as the control, CPF‐5 and CPF‐10, respectively) and its dough, to evaluate consumer acceptance of CPF breads and to identify factors affecting willingness to purchase of CPF breads. Incorporating PF affected rheological and pasting properties of CPF. Water‐ and oil‐holding capacity of CPF increased (P < 0.05) as PF levels increased. Bread made with CPF‐5 was more acceptable than that with CPF‐10; however, it was not significantly different from the control, having similar specific volume and texture, but having about three times higher total dietary fibre than the control (4.4% vs. 1.5%). Product label and health benefit information potentially affected consumers' willingness to purchase of fibre‐enriched bread. 相似文献
8.
CHEN Wuwei ZHU Maofei School of Mechanical Automotive Engineering Hefei University of Technology Hefei China Received February revised September accepted January published electronically November 《机械工程学报(英文版)》2011,(6):1028-1034
The exist researches of the magneto-rheological semi-active suspension(MSAS) control mainly focus on the design of control laws,which aim at obtaining an optimal control strategy to improve the ride comfort and handling stability.In the controller design,the stability of the MSAS system cannot be confirmed owing to the control input time delay considered little.In this paper,a quarter vehicle MSAS model with time-delay is built.Therefore,through formulating the sprung mass acceleration suitably as the optimization object,suspension deflection and tyre dynamic load and coulomb damping force as the constraint objects,with considering the control input time-delay,a delay-dependent state feedback H2/H∞ controller is designed.According to Lyapunov-Krasovskii functional theory,the sufficient conditions for asymptotic stability and the existence of delay-dependent H2/H∞ controller are obtained,and the controller design is transformed into the minimization problem for linear function through linear matrix inequality(LMI).Random road excitation simulations and experiments are carried out.The simulation and experiment results show that the design can preserve the closed-loop stability and achieve the performances for MSAS system in spite of the existence of the control input time-delay.The present study can provide an important basis and method for research on time-delay problem in MSAS and other chassis subsystems.. 相似文献
9.
F. Giordano On behalf of the Fermi-LAT collaboration 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,630(1):163
During the first six months of data taking the Fermi satellite was capable to detect gamma ray emission of the nearby supernova remnant IC443 (G189.1+3.0). IC443 is a shell-type supernova remnant located in the anticenter region where observation can be made clean enough from possible foreground and background overlap, even though care has to be taken due to the vicinity of one of the brightest gamma-ray pulsars, Geminga. IC443 estimated age (20–30 kyr) and the observed two-shell morphology with different radii suggest that the SNR shell has been interacting with surrounding interstellar matter and a neighboring SNR shell. Also the detection of strong molecular emission lines and TeV gamma-ray emission support the idea that the blast has been interacting with dense molecular gas accelerating cosmic-ray particle. After the first year of data taking, Fermi will be surely capable to determine the spatial extension and resolve in much finer details the spectral shape of the gamma-ray emission produced by the accelerated cosmic rays in IC443 distinguished from those of galactic origin. 相似文献
10.