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201.
基于异常与误用的入侵检测系统 总被引:1,自引:0,他引:1
入侵检测系统近年来得到长足的发展,但功能都不够完善.为此将基于误用的入侵检测与基于异常的检测结合为一体.在误用检测上,将检测规则进行分类排序,从而极大地提高了检测效率.异常检测则采用人工免疫技术,使系统对已知的攻击和新型攻击均有较强检测能力. 相似文献
202.
提出一种基于免疫算子的致死染色体复活与利用方法。根据问题的特征信息,优秀染色体和致死染色体的基因信息提取疫苗,通过接种疫苗和免疫选择,以及在“活岛”和“死岛”进行致死染色体和非致死染色体的迁移,实现致死染色体的复活与利用。将算法应用于0-1背包问题,数值实验结果表明,该方法可以有效改善求解约束优化问题遗传算法的性能。 相似文献
203.
自适应性网络环境将成为未来Internet的不可缺少的重要构成部分,基于生物网络中间件设计了自适应软件体系结构,然后设计了一种特殊的生物实体——调度生物实体,利用调度实体来指导生物实体的移动,以期获得生物网络的负载平衡。提出一种基于免疫遗传算法的调度算法,该算法以网络负载平衡为优化目标,使实体相对均衡地提供服务,达到合理利用生物网络资源,增强其自适应性的目的。最后,对网络服务使用进行仿真,实验结果证明了算法的有效性。 相似文献
204.
胡桂武 《计算机工程与应用》2007,43(18):72-74
生物序列motif识别问题是当今生物信息学面临的一个复杂问题,要设计一个能识别所有motif的方法几乎是不可能的。针对该问题,在免疫遗传算法中引入了统计估计,提高了motif识别的精度,根据个体的浓度和适应值概率。设计了免疫替换算子,有效地解决了种群的多样性问题,利用Gibbs Sampler算法生成种子,提高了免疫遗传算法的搜索速度,最后得到了一个基于免疫GA与Gibbs Sampler的生物序列motif识别算法,该算法充分发挥了免疫遗传算法和Gibbs Sampler算法的优越性,较好地解决了计算速度和计算精度之间的矛盾。实验表明,该算法是有效的。 相似文献
205.
Chiara Bellocchi Angelica Carandina Beatrice Montinaro Elena Targetti Ludovico Furlan Gabriel Dias Rodrigues Eleonora Tobaldini Nicola Montano 《International journal of molecular sciences》2022,23(5)
The autonomic nervous system (ANS) and the immune system are deeply interrelated. The ANS regulates both innate and adaptive immunity through the sympathetic and parasympathetic branches, and an imbalance in this system can determine an altered inflammatory response as typically observed in chronic conditions such as systemic autoimmune diseases. Rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis all show a dysfunction of the ANS that is mutually related to the increase in inflammation and cardiovascular risk. Moreover, an interaction between ANS and the gut microbiota has direct effects on inflammation homeostasis. Recently vagal stimulation techniques have emerged as an unprecedented possibility to reduce ANS dysfunction, especially in chronic diseases characterized by pain and a decreased quality of life as well as in chronic inflammation. 相似文献
206.
Tiziana Di Chiara Alessandro Del Cuore Mario Daidone Stefania Scaglione Rosario Luca Norrito Maria Grazia Puleo Rosario Scaglione Antonio Pinto Antonino Tuttolomondo 《International journal of molecular sciences》2022,23(5)
There is growing evidence that hypertension is the most important vascular risk factor for the development and progression of cardiovascular and cerebrovascular diseases. The brain is an early target of hypertension-induced organ damage and may manifest as stroke, subclinical cerebrovascular abnormalities and cognitive decline. The pathophysiological mechanisms of these harmful effects remain to be completely clarified. Hypertension is well known to alter the structure and function of cerebral blood vessels not only through its haemodynamics effects but also for its relationships with endothelial dysfunction, oxidative stress and inflammation. In the last several years, new possible mechanisms have been suggested to recognize the molecular basis of these pathological events. Accordingly, this review summarizes the factors involved in hypertension-induced brain complications, such as haemodynamic factors, endothelial dysfunction and oxidative stress, inflammation and intervention of innate immune system, with particular regard to the role of Toll-like receptors that have to be considered dominant components of the innate immune system. The complete definition of their prognostic role in the development and progression of hypertensive brain damage will be of great help in the identification of new markers of vascular damage and the implementation of innovative targeted therapeutic strategies. 相似文献
207.
The healing of skin wounds involves the activation and recruitment of various immune cell types, many of which are believed to contribute significantly to different aspects of the repair process. Roles for immune cells have been described in practically all stages of wound healing, including hemostasis, inflammation, proliferation and scar formation/remodeling. Over the last decade, tools to deplete immune cell populations in animal models have become more advanced, leading to a surge in the number of studies examining the function of specific immune cell types in skin repair. In this review, we will summarize what is known about distinct immune cell types in cutaneous wound healing, with an emphasis on data from animal studies in which specific cell types have been targeted. 相似文献
208.
Tao Gong Juan Du Shang-Wei Li Hai Huang Xiao-Lang Qi 《International journal of molecular sciences》2022,23(5)
Coridius chinensis belongs to Dinidoridae, Hemiptera. Previous studies have indicated that C. chinensis contains abundant polypeptides with antibacterial and anticancer activities. Antimicrobial peptides (AMPs), as endogenous peptides with immune function, play an indispensable role in the process of biological development and immunity. AMPs have become one of the most potential substitutes for antibiotics due to their small molecular weight and broad-spectrum antimicrobial activity. In this study, a defensin CcDef2 from C. chinensis was characterized based on bioinformatics and functional analyses. The mature peptide of CcDef2 is a typical cationic peptide composed of 43 amino acid residues with five cations, and contains three intramolecular disulfide bonds and a typical cysteine-stabilized αβ motif in defensins. Phylogenetic analysis showed that CcDef2 belongs to the insect defensin family. Analysis of gene expression patterns showed that CcDef2 was expressed throughout developmental stages of C. chinensis with high levels at the nymphal stage and in adult tissues tested with the highest level in the fat body. In addition, the CcDef2 expression was significantly upregulated in adults infected by bacteria. After expressed in Escherichia coli BL21(DE3) and renatured, the recombinant CcDef2 showed a significant antibacterial effect on three kinds of Gram-positive bacteria. These results indicate that CcDef2 is an excellent antibacterial peptide and a highly effective immune effector in the innate immunity of C. chinensis. This study provides a foundation for further understanding the function of CcDef2 and developing new antimicrobial drugs. 相似文献
209.
210.
The smart meter is a basic device of the smart grid, which improves the efficiency of the power grid and brings a lot of convenience for the industry and people’s daily life. However, real-time power consumption data contain some sensitive information, and could disclose the privacy of users. As an immunological technique, the negative survey is proposed to preserve the privacy of static data. In this paper, firstly, we demonstrate that traditional negative survey might disclose the privacy of users when it is used to collect time-series data. Secondly, we propose an improved negative survey method for collecting the time-series data. Thirdly, for the first time, we apply the negative survey to preserving the privacy of the power consumption data aggregated from smart meters. Theoretical analysis and experimental results demonstrate that the method proposed in this paper could aggregate the power consumption data while preserving the privacy of users. Compared with existing techniques, our method is simple and efficient, and does not need a trusted third party. Moreover, it could tolerate the failure of some users and resist differential attack. 相似文献