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71.
Veronika Karnowski Larissa Leonhard Anna Sophie Kümpel 《Communication Research Reports》2018,35(2):91-100
Social media have become an integral part of online news use, affecting how individuals find, consume, and share news. By applying the Theory of Reasoned Action (TRA), this study investigates the effects of motives, attitude, and intention on news-sharing behavior among German social media users (n = 333). Findings show that news-sharing attitude and subjective norms have a positive effect on news-sharing intention, which in turn has a positive effect on actual news-sharing behavior. Taken together, we see that a new media behavior in the early phases of its societal diffusion—like social media news sharing in Germany in 2015—can mainly be explained by a rational choice logic and is rooted in the motives of socializing and information seeking. This finding thus reflects the double nature of social media as a means for both information retrieval and social grooming. 相似文献
72.
Holly Thompson 《Medical reference services quarterly》2018,37(1):97-104
The National Institutes of Health (NIH) library instruction program provides training services to staff, clinicians, and researchers across NIH and several Department of Health and Human Services (HHS) operating divisions. The audience, training needs, and training topics are diverse and constantly changing. The NIH library has developed several new services and class topics to meet the needs of its NIH and HHS communities. Context, strategies, and future directions for the NIH library instruction program are described. 相似文献
73.
Lotta Haglund Annikki Roos Petra Wallgren‐Björk 《Health information and libraries journal》2018,35(3):251-255
Librarians in Sweden are facing huge challenges in meeting the demands of their organisations and users. This article looks at four key areas: coping with open science/open access initiatives; increasing demands from researchers for support doing systematic reviews; understanding user experiences in Swedish health science libraries; and the consequences of expanding roles for recruitment and continuing professional development. With regard to changing roles, there is an increasing shift from the generalist towards the expert role. The authors raise the issue as to how to prepare those new to the profession to the changing environment of health science libraries. 相似文献
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75.
Yunlong CHENG Shu LIAN Shuhui LI Yusheng LU Jie WANG Xiaoxiao DENG Shengyi ZHAI Lee JIA 《Journal of Zhejiang University. Science. B》2022,23(11):943
ObjectivePrimary tumor treatment through surgical resection and adjuvant therapy has been extensively studied, but there is a lack of effective strategies and drugs for the treatment of tumor metastases. Here, we describe a functional product based on a combination of compounds, which can be used as an adjuvant therapy and has well-known mechanisms for inhibiting cancer metastases, improving anti-cancer treatment, and enhancing immunity and antioxidant capacity. Our designed combination, named MVBL, consists of four inexpensive compounds: L-selenium-methylselenocysteine (MSC), D-α-tocopheryl succinic acid (VES), β-carotene (β-Ca), and L-lysine (Lys).MethodsThe effects of MVBL on cell viability, cell cycle, cell apoptosis, cell migration, cell invasion, reactive oxygen species (ROS), and paclitaxel (PTX)-combined treatment were studied in vitro. The inhibition of tumor metastasis, antioxidation, and immune enhancement capacity of MVBL were determined in vivo.ResultsMVBL exhibited higher toxicity to tumor cells than to normal cells. It did not significantly affect the cell cycle of cancer cells, but increased their apoptosis. Wound healing, adhesion, and transwell assays showed that MVBL significantly inhibited tumor cell migration, adhesion, and invasion. MVBL sensitized MDA-MB-231 breast cancer cells to PTX, indicating that it can be used as an adjuvant to enhance the therapeutic effect of chemotherapy drugs. In mice, experimental data showed that MVBL inhibited tumor metastasis, prolonged their survival time, and enhanced their antioxidant capacity and immune function.ConclusionsThis study revealed the roles of MVBL in improving immunity and antioxidation, preventing tumor growth, and inhibiting metastasis in vitro and in vivo. MVBL may be used as an adjuvant drug in cancer therapy for improving the survival and quality of life of cancer patients. 相似文献
76.
Yi-Feng Wang Chunqiu Zhang Keni Yang Yufei Wang Shaobo Shan Yan Yan Kenneth A Dawson Chen Wang Xing-Jie Liang 《国家科学评论(英文版)》2021,8(6):17-27
Liposomes, especially cationic liposomes, are the most common and well-investigated nanocarriers for biomedical applications, such as drug and gene delivery. Like other types of nanomaterials, once liposomes are incubated in a biological milieu, their surface can be immediately cloaked by biological components to form a protein corona, which confers a new ‘biological identity’ and modulates downstream interactions with cells. However, it remains unclear how the protein corona affects the transportation mechanism after liposomes interact with cells. Here, we employed home-made aggregation-induced-emission-visualized nanoliposomes TR4@Lipo as a model to investigate transportation with or without the protein corona by optical imaging techniques. The results show that the protein corona can change the cellular transportation mechanism of TR4@Lipo from energy-independent membrane fusion to energy-dependent endocytosis. The protein corona also modulates the intracellular distribution of loaded cargoes. This knowledge furthers our understanding of bio-nano interactions and is important for the efficient use of cationic liposomes. 相似文献
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78.
目前ARP欺骗攻击呈现出越来越严重的趋势,已成为导致校园网大面积断网甚至瘫痪的首要原因。本文针对校园网中遭受ARP欺骗攻击,分析了其攻击原理、现象,并提出了切实可行的解决方法和防范策略。 相似文献
79.
融合研究是促进科学技术发展的新范式,不仅会促进科学技术取得突破性发展,而且是解决21世纪人类面临宏大挑战的一种重要途径。文章考察了融合研究的内涵和特点,以及美国国家科学基金会(NSF)融合研究的概念;根据NSF十大投入计划和新的战略规划(2018—2022年),指出发展融合研究在NSF中的战略地位;分析NSF支持融合研究的基础和融合项目的特点,并对第一批融合项目的实施作了介绍;总结出NSF支持融合研究可供借鉴的若干结论,并对我国发展融合研究提出若干建议。 相似文献
80.
波士顿咨询集团矩阵是对企业经营的全部产品或者业务组合进行整体分析的一种重要的战略工具。本文分析大学利用波士顿咨询集团矩阵进行学科规划的情况,并且对大学利用波士顿咨询集团矩阵进行学科和专业规划的情况进行评价。 相似文献