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排序方式: 共有331条查询结果,搜索用时 15 毫秒
91.
In a recent work [D. Campos, J.E. Llebot, V. Méndez, Theor. Popul. Biol. 74 (2009) 16] we have introduced a biological version of the Evolutionary Minority Game that tries to reproduce the intraspecific competition for limited resources in an ecosystem. In comparison with the complex decision-making mechanisms used in standard Minority Games, only two extremely simple strategies (juveniles and adults) are accessible to the agents. Complexity is introduced instead through an evolutionary learning rule that allows younger agents to learn taking better decisions. We find that this game shows many of the typical properties found for Evolutionary Minority Games, like self-segregation behavior or the existence of an oscillation phase for a certain range of the parameter values. However, an analytical treatment becomes much easier in our case, taking advantage of the simple strategies considered. Using a model consisting of a simple dynamical system, the phase diagram of the game (which differentiates three phases: adults crowd, juveniles crowd and oscillations) is reproduced. 相似文献
92.
Recent investigation indicated that latent reservoir and immune impairment are responsible for the post-treatment control of HIV infection. In this paper, we simplify the disease model with latent reservoir and immune impairment and perform a series of mathematical analysis. We obtain the basic infection reproductive number $R_{0}$ to characterize the viral dynamics. We prove that when $R_{0}<1$, the uninfected equilibrium of the proposed model is globally asymptotically stable. When $R_{0}>1$, we obtain two thresholds, the post-treatment immune control threshold and the elite control threshold. The model has bistable behaviors in the interval between the two thresholds. If the proliferation rate of CTLs is less than the post-treatment immune control threshold, the model does not have positive equilibria. In this case, the immune free equilibrium is stable and the system will have virus rebound. On the other hand, when the proliferation rate of CTLs is greater than the elite control threshold, the system has stable positive immune equilibrium and unstable immune free equilibrium. Thus, the system is under elite control. 相似文献
93.
94.
Sundo Jung Yoon-Kyung Park Jung Hoon Shin Hyunji Lee Soo-Young Kim Gap Ryol Lee Se-Ho Park 《Experimental & molecular medicine》2010,42(8):547-554
TGF-β-induced tolerogenic-antigen presenting cells (Tol-APCs) could induce suppression of autoimmune diseases such as collagen-induced arthritis (CIA) and allergic asthma. In contrast, many studies have shown that NKT cells are involved in the pathogenesis of Th1-mediated autoimmune joint inflammation and Th2-mediated allergic pulmonary inflammation. In this study, we investigated the effect of CD1d-restricted NKT cells in the Tol-APCs-mediated suppression of autoimmune disease using a murine CIA model. When CIA-induced mice were treated with Tol-APCs obtained from CD1d+/- or CD1d-/- mice, unlike CD1d+/- APCs, CD1d-/- Tol-APCs failed to suppress CIA. More specifically, CD1d-/- Tol-APCs failed to suppress the production of inflammatory cytokines and the induction of Th2 responses by antigen-specific CD4 T cells both in vitro and in vivo. Our results demonstrate that the presence of CD1d-restricted NKT cells is critical for the induction of Tol-APCs-mediated suppression of CIA. 相似文献
95.
生物素-亲和素系统在压电免疫传感器中质量放大作用研究 总被引:4,自引:0,他引:4
生物素-亲和素系统(BiotinAvidinSystem,BAS)是70年代后期迅速发展起来的一种新型生物放大系统,具有高灵敏度、高特异性以及简便、经济、快速等优点,在现代生物免疫学领域中已得到广泛的应用[1]. 相似文献
96.
在pH 6.0的柠檬酸-Na2HPO4缓冲溶液中及PEG-6000存在下, C反应蛋白(CRP)与羊抗人C反应蛋白可聚集形成免疫复合物微粒, 在350, 390, 440 nm处有三个共振散射峰. 激光散射法测得免疫复合物微粒的平均粒径为1720.0 nm. 在最佳实验条件下, CRP浓度在0.03~1.80 μg•mL-1的范围内与390, 440 nm处共振散射强度都呈良好的线性关系, 其回归方程、相关系数、检出限分别为ΔI390 nm=306.4c+17.3, ΔI440 nm=296.0c+10.7; 0.9993, 0.9996; 0.011, 0.012 μg•mL-1. 该方法选择性较好, 操作简便, 用于人血清中C反应蛋白的测定, 结果与免疫透射比浊法结果一致, 相对标准偏差在0.90%~4.12%. 相似文献
97.
Narcy Arizmendi Syed Benazir Alam Khalid Azyat Darren Makeiff A. Dean Befus Marianna Kulka 《Molecules (Basel, Switzerland)》2022,27(8)
Sesquiterpenes (SQs) are volatile compounds made by plants, insects, and marine organisms. SQ have a large range of biological properties and are potent inhibitors and modulators of inflammation, targeting specific components of the nuclear factor-kappaB (NF-κB) signaling pathway and nitric oxide (NO) generation. Because SQs can be isolated from over 1600 genera and 2500 species grown worldwide, they are an attractive source of phytochemical therapeutics. The chemical structure and biosynthesis of SQs is complex, and the SQ scaffold represents extraordinary structural variety consisting of both acyclic and cyclic (mono, bi, tri, and tetracyclic) compounds. These structures can be decorated with a diverse range of functional groups and substituents, generating many stereospecific configurations. In this review, the effect of SQs on inflammation will be discussed in the context of their complex chemistry. Because inflammation is a multifactorial process, we focus on specific aspects of inflammation: the inhibition of NF-kB signaling, disruption of NO production and modulation of dendritic cells, mast cells, and monocytes. Although the molecular targets of SQs are varied, we discuss how these pathways may mediate the effects of SQs on inflammation. 相似文献
98.
Elisa Domi Malvina Hoxha Entela Kolovani Domenico Tricarico Bruno Zappacosta 《Molecules (Basel, Switzerland)》2022,27(8)
Since COVID-19 has affected global public health, there has been an urgency to find a solution to limit both the number of infections, and the aggressiveness of the disease once infected. The main characteristic of this infection is represented by a strong alteration of the immune system which, day by day, increases the risk of mortality, and can lead to a multiorgan dysfunction. Because nutritional profile can influence patient’s immunity, we focus our interest on resveratrol, a polyphenolic compound known for its immunomodulating and anti-inflammatory properties. We reviewed all the information concerning the different roles of resveratrol in COVID-19 pathophysiology using PubMed and Scopus as the main databases. Interestingly, we find out that resveratrol may exert its role through different mechanisms. In fact, it has antiviral activity inhibiting virus entrance in cells and viral replication. Resveratrol also improves autophagy and decreases pro-inflammatory agents expression acting as an anti-inflammatory agent. It regulates immune cell response and pro-inflammatory cytokines and prevents the onset of thrombotic events that usually occur in COVID-19 patients. Since resveratrol acts through different mechanisms, the effect could be enhanced, making a totally natural agent particularly effective as an adjuvant in anti COVID-19 therapy. 相似文献
99.
针对目前计算机取证技术因为取证时间的滞后而缺乏实效性的不足,提出了一种基于人工免疫原理和Multi—Agent理论的计算机动态取证方法.该方法结合了人工免疫系统在入侵检测中的优势及Multi-Agent系统在体系结构上的分布式特点,能够在网络攻击一旦发生的时候动态地收集实时数字证据,并通过安全有效的方式将证据及时、完整地加以保存,为证据的收集和分析工作提供可信的原始数据.同时能够确保数字证据安全有效地传输及保存.实验表明该方法能够确保证据的真实、完整和有效,为计算机动态取证的实现提供了一种新的思路. 相似文献
100.