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排序方式: 共有9238条查询结果,搜索用时 106 毫秒
1.
Hepatocellular carcinoma (HCC) is one of the most prevalent malignancies worldwide. HCC is associated with several etiological factors, including HBV/HCV infections, cirrhosis, and fatty liver diseases. However, the molecular mechanism underlying HCC development remains largely elusive. The advent of high-throughput sequencing has unveiled an unprecedented discovery of a plethora of long noncoding RNAs (lncRNAs). Despite the lack of coding capacity, lncRNAs have key roles in gene regulation through interacting with various biomolecules. It is increasingly evident that the dysregulation of lncRNAs is inextricably linked to HCC cancer phenotypes, suggesting that lncRNAs are potential prognostic markers and therapeutic targets. In light of the emerging research in the study of the regulatory roles of lncRNAs in HCC, we discuss the association of lncRNAs with HCC. We link the biological processes influenced by lncRNAs to cancer hallmarks in HCC and describe the associated functional mechanisms. This review sheds light on future research directions, including the potential therapeutic applications of lncRNAs. 相似文献
2.
《International Journal of Hydrogen Energy》2021,46(62):31788-31797
Many places experience extreme temperatures below −30 °C, which is a great challenge for the fuel cell vehicle (FCV). The aim of this study is to optimize the strategy to achieve rapid cold start-up of the 30-cell stack at different temperature conditions. The test shows that the stack rapidly starts within 30 s at an ambient temperature of −20 °C. Turning on the coolant at −25 °C show stability of the cell voltage at both ends due to the end-plate heating, however, voltage of intermediate cells fluctuates sharply, and successful start-up is completed after 60 s. The cold start strategy changes to load-voltage cooperative control mode when the ambient temperature reduced to −30 °C, the voltage of multiple cells in the middle of the stack fluctuate more drastic, and start-up takes 113 s. The performance and consistency of the stack did not decay after 20 cold start-up experiments, which indicates that our control strategies effectively avoided irreversible damage to the stack caused by freeze-thaw process. 相似文献
3.
This paper reviews the fire problem in critical transportation infrastructures such as bridges and tunnels. The magnitude of the fire problem is illustrated, and the recent increase in fire problems in bridges and tunnels is highlighted. Recent research undertaken to address fire problems in transportation structures is reviewed, as well as critical factors governing the performance of those structures. Furthermore, key strategies recommended for mitigating fire hazards in bridges and tunnels are presented, and their applicability to practical situations is demonstrated through a practical case study. Furthermore, research needs and emerging trends for enhancing the “state-of-the-art” in this area are discussed. 相似文献
4.
云冈矿因为煤炭资源的过度开采,引发了地面塌陷及地裂缝等一系列的地质灾害。对云冈矿地质灾害现状进行了分析,在立足采空区分布状况的基础上,采用地质测绘、地质调查、物探勘察、钻探验证综合技术对该矿采空区“三带”进行有效判断,提出了该煤矿采空区地质灾害治理方案,灌浆质量检查结果理想。 相似文献
5.
Lei Yuan Mads Frederik Hansen Henriette Lyng Røder Ni Wang 《Critical reviews in food science and nutrition》2020,60(13):2277-2293
AbstractAttachment of microorganisms to food contact surfaces and the subsequent formation of biofilms may cause equipment damage, food spoilage and even diseases. Mixed-species biofilms are ubiquitous in the food industry and they generally exhibit higher resistance to disinfectants and antimicrobials compared to single-species biofilms. The physiology and metabolic activity of microorganisms in mixed-species biofilms are however rather complicated to study, and despite targeted research efforts, the potential role of mixed-species biofilms in food industry is still rather unexplored. In this review, we summarize recent studies in the context of bacterial social interactions in mixed-species biofilms, resistance to disinfectants, detection methods, and potential novel strategies to control the formation of mixed-species biofilms for enhanced food safety and food quality. 相似文献
6.
Although the unprecedented prevalence of social media has infiltrated into international students’ daily trajectories and become an indispensable component of their intercultural communication, yet surprisingly few attempts have been implemented to systematically unpack how the innovative technology could play a role in these sojourners’ acculturation experiences and the consequences of migration and cross-cultural adaption. In order to address such research gap, the objective of this present article is to provide a review of academic, peer-reviewed journal studies that examined the potential effect of social media engagement on international university students’ acculturation process, coping strategies, and psychological adjustments during the period from 2010 to 2019. Moreover, building upon conceptualizations from new media and transcultural research literature, a conceptual framework was developed to classify the relevant studies for further analysis. Overall, these theories and studies synthesized in this paper emphasize the vital role of social media in the acculturation, coping behaviors and mental health for ethnic minorities in the host country. Additionally, certain dimensions of attitudes and behaviors through social media could exert the important influence on the psychological adaption. Therefore, conclusions of the research may assist to further inform practitioners who may encounter newcomers’ experiencing intercultural adjustments and psychological issues in the digital media age. Furthermore, this current review may also help educators determine certain barriers that have not been resolved in campus tactics which may influence the acculturation of sojourning populations. 相似文献
7.
针对长江水资源开发保护中存在的主要问题,以及新时代长江经济带发展和长江大保护背景下面临的新要求,展开了专项分析研究。研究结果表明:正确把握长江水资源开发保护与水环境治理及经济社会发展之间的关系,是协调长江经济带发展与长江大保护的关键所在。根据研究结果,提出了应当以水环境改善为突破点的长江水资源、水环境、水生态以及水灾害等四水共治的思路;同时还提出了管理与技术、经济与法律及文化等多种手段相结合的针对长江水资源开发保护的对策和建议。 相似文献
8.
根据商用车制动盘铸件粘砂缺陷废品所占比例及分布规律,结合所使用的造型线工艺特点和产品结构特点进行初步分析。为准确判断严重粘砂缺陷的产生原因,制取粘砂缺陷试样,采用金相显微镜、扫描电镜等进一步准确分析,发现总高度较高的商用车制动盘在原有工艺条件下产生的粘砂缺陷类型为机械粘砂缺陷,主要原因为砂型充填不紧实、型腔排气不畅及铁液静/动压力过大。最后,通过模拟分析,提出了简单有效的解决对策,将铸件的大部分置于上箱,并采用底注式浇注工艺,使机械粘砂缺陷废品得到彻底消除。 相似文献
9.
Ji-Youn Kim Chang-Hyeon An Jae-Young Kim Jae-Kwang Jung 《International journal of molecular sciences》2020,21(22)
Salivary secretory disorders are life-disrupting pathologic conditions with a high prevalence, especially in the geriatric population. Both patients and clinicians frequently feel helpless and get frustrated by the currently available therapeutic strategies, which consist mainly of palliative managements. Accordingly, to unravel the underlying mechanisms and to develop effective and curative strategies, several animal models have been developed and introduced. Experimental findings from these models have contributed to answer biological and biomedical questions. This review aims to provide various methodological considerations used for the examination of pathological fundamentals in salivary disorders using animal models and to summarize the obtained findings. The information provided in this review could provide plausible solutions for overcoming salivary disorders and also suggest purpose-specific experimental animal systems. 相似文献
10.
“Join a Meetup Group” (face-to-face study group) has been propagated by Coursera to build rapport and provide mutual support among MOOC learners; however, studies remain scant regarding its effectiveness and sustainability. This interpretive case study documents our facilitation process, key influential factors, as well as student perceived gains in a six-week MOOC study group. Data sources include discussion recordings, end-of-course interviews, goal setting sheets, weekly reflection journals, and researchers' observation notes. Results showed that, cognitively, participants broadened their perspective of thinking, raised cultural awareness, and shared many learning strategies. Affectively, they established a strong sense of community and gained motivation for learning. Participants also increased action tendencies toward trying out Coursera functions, new courses, and learning strategies, and they became more cognizant of the benefits and procedures of the MOOC study group. Our findings suggest that, with proper design and facilitation, face-to-face study group would be a practicable and effective approach to leverage MOOC students' motivation, engagement, and deeper learning. Implications are discussed in terms of potential gains, challenges, key influential factors, as well as future design and implementation of MOOC study groups. 相似文献