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排序方式: 共有615条查询结果,搜索用时 29 毫秒
1.
Vancha Harish Effi Haque Magdalena
miech Hiroaki Taniguchi Sarah Jamieson Devesh Tewari Anupam Bishayee 《International journal of molecular sciences》2021,22(9)
Xanthohumol (XH) is an important prenylated flavonoid that is found within the inflorescence of Humulus lupulus L. (Hop plant). XH is an important ingredient in beer and is considered a significant bioactive agent due to its diverse medicinal applications, which include anti-inflammatory, antimicrobial, antioxidant, immunomodulatory, antiviral, antifungal, antigenotoxic, antiangiogenic, and antimalarial effects as well as strong anticancer activity towards various types of cancer cells. XH acts as a wide ranging chemopreventive and anticancer agent, and its isomer, 8-prenylnaringenin, is a phytoestrogen with strong estrogenic activity. The present review focuses on the bioactivity of XH on various types of cancers and its pharmacokinetics. In this paper, we first highlight, in brief, the history and use of hops and then the chemistry and structure–activity relationship of XH. Lastly, we focus on its prominent effects and mechanisms of action on various cancers and its possible use in cancer prevention and treatment. Considering the limited number of available reviews on this subject, our goal is to provide a complete and detailed understanding of the anticancer effects of XH against different cancers. 相似文献
2.
Annie I. Anton Julia B. Eart Matthew W. Vail Neha Jain Carrie M. Gheen Jack M. Frink 《Security & Privacy, IEEE》2007,5(1):45-52
Healthcare institutions typically post their privacy practices online as privacy policy documents. We conducted a longitudinal study that examines the effects of HIPAA's enactment on a collection of privacy policy documents for a fixed set of organizations over a four-year period. We present our analysis of 24 healthcare privacy policy documents from nine healthcare Web sites, analyzed using goal mining, a content-analysis method that supports extraction of useful information about institutions' privacy practices from documents. We compare our results to our pre-HIPAA study of these same institutions' online privacy practices and evaluate their evolution in the presence of privacy laws 相似文献
3.
4.
5.
Real-time payments for mobile IP 总被引:2,自引:0,他引:2
The mobile IP protocol has evolved from providing mobility support for portable computers to support for wireless handheld devices with high mobility patterns. A new category of micromobility protocols has been proposed to deal with the increased signaling loads that will be generated with large populations of such devices on a network. We argue that the authentication schemes presently employed in these networks do not scale well for large numbers of nodes, and that the lack of accounting procedures prevents the mass deployment of these networks. We envisage that future access networks will be operated by independent service providers, who will charge users for access to services in the fixed network but may not have long-term contractual relationships with them. These access networks may also employ a variety of micromobility protocols for fast handover support. We present a scheme based on hash chains, which allows for fast authentication of datagrams for secure updating of router entries within the access network, and real-time accounting of network usage by mobile nodes. Such a system will alleviate problems of fraud in mobile networks and eliminate the need for interoperator billing agreements. 相似文献
6.
7.
G. K. Dey R. Tewari P. Rao S. L. Wadekar P. Mukhopadhyay 《Metallurgical and Materials Transactions A》1993,24(1):2709-2719
The occurrence of a significant amount of age hardening, due to the precipitation of the γ′ phase, has been demonstrated in
the nickel-copper base alloy MONEL K 500. The microstructure of the precipitation-hardened and deformed alloy has been examined
in peak-aged underaged and overaged conditions. An attempt has been made to compare the observed increments in strength in
these three aged conditions to those predicted on the basis of relevant theoretical models. 相似文献
8.
9.
Adam N.R. Tewari R. 《IEEE transactions on pattern analysis and machine intelligence》1993,19(6):594-602
The authors consider the consistency control problem for replicated data in a distributed computing system (DCS) and propose a new algorithm to dynamically regenerate copies of data objects in response to node failures and network partitioning in the system. The DCS is assumed to have strict consistency constraints for data object copies. The algorithm combines the advantages of voting-based algorithms and regeneration mechanisms to maintain mutual consistency of replicated data objects in the case of node failures and network partitioning. The algorithm extends the feasibility of regeneration to DCS on wide area networks and is able to satisfy user queries as long as there is one current partition in the system. A stochastic availability analysis of the algorithm shows that it provides improved availability as compared to previously proposed dynamic voting algorithms 相似文献
10.
H. S. Tewari Om Parkash V. B. Tare Devendra Kumar 《Journal of Materials Science》1990,25(4):2181-2184
The dielectric behaviour of the compositions withx0.15 in the system Ca1–x
Y
x
Ti1–x
Co
x
O3 sintered and cooled in air has been studied. Space-charge polarization which arises due to the presence of chemical inhomogeneities at the micro-level contributes significantly to their dielectric constant. The composition with x=0.05 exhibits temperature and frequency-independent dielectric constant and very small dielectric loss. 相似文献