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1.
锌与有氧运动对肥胖患者体重指数和细胞免疫功能的作用   总被引:4,自引:0,他引:4  
探讨微量元素锌与有氧运动对肥胖患者细胞免疫功能的影响。将30例12~30岁肥胖患者按体重指数值随机分为补锌有氧运动组和有氧运动组,采用PHA体外诱导淋巴细胞增殖,观测诱导后淋巴细胞的增殖能力,并测定细胞因子IL-2和IFN-γ血清浓度的变化;用LDH释放法测定NK和LAK细胞的杀伤活性,对结果进行统计学处理。两组结果相比较,经过锻炼后体重指数均下降,但补锌有氧运动组下降更为明显(P<0.05);补锌有氧运动组患者血液的淋巴细胞对PHA诱导的增殖能力显著增强(P<0.05);血清IL-2和IFN-γ水平也显著升高(P<0.05);NK和LAK细胞的杀伤活性亦明显增强(P<0.05)。补锌加有氧运动可以改善肥胖患者细胞免疫功能状态,降低体重,增强机体的抵抗力,有利于帮助患者机体康复。  相似文献   
2.
目的:外泌体及其内容物是各种肝脏疾病的潜在生物标志物。本研究探索外泌体及其内容物在肝移植排斥反应及预后中的作用。创新点:本研究发现外泌体及内含物半乳糖凝集素-9(galectin-9)在肝移植术后排斥及预后预测中发挥重要作用。方法:分别从急性排斥和肝功能稳定患者提取外泌体,进行分离、鉴定并检测其内含蛋白。候选蛋白通过在73个急性排斥病人和63个肝功能稳定病人切除肝的组织芯片中进行验证。最后将蛋白表达量和临床参数纳入Kaplan-Meier生存率和Cox回归分析。结论:外泌体来源的galectin-9可作为预测肝移植术后排斥发生及预后的生物学指标。  相似文献   
3.
本文研究一类区间时变扰动神经网络系统周期解的鲁棒指数稳定性.获得了一系列关于鲁棒指数稳定性的判据.  相似文献   
4.
Traffic flows controlled by traffic light strategies were investigated via a cellular automaton model with anticipation, which is suitable for describing urban traffic. Three kinds of strategies, i. e., synchronized, green-wave and random switching lights, were designed, simulated and compared with each other. It is shown that the green-wave strategy is only valid at lower density and there is not an effective way with the three strategies to improve the efficiency of traffic flow at high density.  相似文献   
5.
基于物理元胞自动机的岩石破坏模拟   总被引:1,自引:0,他引:1  
为了分析岩石材料的非均质性对其破坏演化的影响,根据元胞自动机理论,从能量的角度建立了一种能够从细观层次上对岩石破坏演化进行模拟的物理元胞自动机模型(Mh-PCA模型),模型引用的Weibull随机分布函数对材料的非均质性进行描述.运用该模型,对m分别为1,5,10,15四种不同均质度材料的破坏模式及其破坏过程中的声发射现象进行了模拟分析.结果表明:材料的非均质性对其破坏有重要的影响,均质度越高,破坏过程中的分支裂纹越少,声发射也越集中.物理元胞自动机理论为岩石的破坏研究提供了一种新的研究思路.  相似文献   
6.
Immunization with a proper dose of an antigenic stimulus leads to cell proliferation and antibody response of circulating lymphocytes. We have previously observed that Secondary immunized spleenocytes resist ceramide-mediated apoptosisin vitro. Our present study is aimed at investigating thein vivo effect of immunization on apoptosis. Mice were subjected to either Primary or Secondary dose with Tetanus Toxoid. Unimmunized spleenocytes served as controls. Unimmunized, Primary and Secondary immunized mice were later exposed to chemotherapeutic drugs such as Etoposide/Methotrexate/Vincristine to induce apoptosis. Apoptosis was studied by using the Feulgen reaction on 5μ thin parafin sections of spleen. It was observed that Secondary immunized mice showed a lower percentage of apoptosis as compared to Primary or Unimmunized mice that was subjected to either of the chemotherapeutic drugs. It was thus concluded that Secondary immunization inhibits the process of chemotherapeutic drug induced apoptosis in vivo.  相似文献   
7.
在信道复用距离为常数,相邻的基站信道相差的条件下,研究了蜂窝状通信系统的最优信道分配问题。给出了此信道分配问题的数学模型,并论证了该模型求出的是最优解,并深入阐述了通信系统的信道分配问题。  相似文献   
8.
According to its proponents, animal-free animal food products, such as cultured meat and synthetic cow’s milk, have the potential to overcome various environmental, health and ethical challenges that have emerged around global animal product consumption and the industrial agriculture that is needed to support it. Apart from the myriad of technical problems making animal-free food products, critics have pointed out the blurry ontological status of the food and the ethical challenges therein, and have questioned the veracity of the various promissory narratives being produced. This paper considers animal-free food from a social studies of economies and markets (SSEM) perspective. As a market that currently mostly only exists in potential, an SSEM perspective can reveal the various social and material relations that comprise the (bio)capital formation that will underpin any market-to-be, an aspect of markets that are often invisible once markets are up and running. Moreover, this perspective details the intimate role markets have in establishing the ethical and ontological aspects of animal-free foods in a political economy shaped by neoliberalisation and financialisation.  相似文献   
9.
急性运动对人体细胞免疫功能的影响   总被引:7,自引:0,他引:7  
为探索运动对细胞免疫功能的影响,检测了7名男运动员一次急性疲劳性运动前和运动后即刻、3h、24h的外周血TLT、IH活性和皮质醇及胰岛素浓度的变化。结果:在运动后即刻,TLT显著增强,IL—2活性和血浆皮质醇浓度分别略有上升和下降;在运动后3h,前2项指标和血浆皮质醇浓度分别明显增强和降低。这3项指标在运动后24h均恢复到运动前水平。IL-2活性变化与皮质醇变化有显著负相关关系。胰岛素在运动前后无明显变化。结果表明:一次急性适度运动可提高人体的细胞免疫功能,并可持续数小时。这种变化与血浆皮质醇浓度下降有一定关系。  相似文献   
10.
The set of papers [3], [4], [6] and [7] (Chattopadhyay et al., 1999; Dihidar and Choudhury, 2004; Khan et al., 1997, 1999) deals with the behavior of the uniform two-dimensional cellular automata over binary fields (Z2). Some structural properties and precise mathematical models using matrix algebra over the field Z2 are reported for characterizing the behavior of two-dimensional nearest neighborhood linear cellular automata with null and periodic boundary conditions [3], [4], [6] and [7] (Chattopadhyay et al., 1999; Dihidar and Choudhury, 2004; Khan et al., 1997, 1999). In this paper, we characterize two-dimensional linear cellular automata transformations by using matrix algebra built on Z3. We analyze some results for two-dimensional CA with rule numbers 2460N and 2460P. Finally, we investigate the dimension of the kernel of two-dimensional cellular automata defined by the rule number 2460N.  相似文献   
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