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31.
M Cuchacovich NN Tchernitchin H Gatica R Wurgaft L Contreras AN Tchernitchin 《Canadian Metallurgical Quarterly》1996,124(2):160-169
BACKGROUND: The target cellular response to glucocorticoids is proportional to the concentrations or affinity of specific receptors to these substances. AIM: To look for a correlation between glucocorticoid receptor concentrations in synovial wall cells and the clinical response to steroidal treatment in patients with rheumatoid arthritis. PATIENTS AND METHODS: Twenty eight patients with rheumatoid arthritis were studied. Each subject was subjected to a synovial biopsy, in which a dry radioautographic technique for diffusible compounds was used. Patients were treated afterwards with three 500 mg intravenous pulses of methilprednisolone. RESULTS: A mean of 44.8% of synovial cells (range 30.1-62.8%) had binding sites for 3H dexamethasone. All patients had a significant clinical improvement after methylprednisolone. Multiple regression analysis did not show a correlation between clinical response and glucocorticoid receptor concentration. CONCLUSIONS: The lack of association between glucocorticoid receptor concentrations and clinical response could be due to the large steroid dose used, that saturated all available receptors. 相似文献
32.
Gluconobacter oxydans possesses a unique organization of metabolic systems, which are characterized by reduction of major dissimilation pathways, surface localization of main oxidative enzymes responsible for partial oxidation of carbon substrates, high performance of electron-transport chains, and accumulation of partially oxidized metabolites in the medium. These features allow us to use the cells of these microorganisms in biotechnology for production of several food products and medicines. The use of G. oxydans in biosensors for estimation of concentrations of sugars, aldoses and polyalcohols is promising. Physiological and biochemical features of these microorganisms enabling their use in biotechnology and receptor elements of biosensors are reviewed. 相似文献
34.
Ma Bin Chang Lili Wang Chunpeng Li Jian Li Gang Xia Zhiqiu Wang Xingyuan 《Journal of Mathematical Imaging and Vision》2021,63(9):1160-1178
Journal of Mathematical Imaging and Vision - Different from the traditional watermarking schemes, zero-watermarking schemes are lossless embedding methods, which are applicable to be used in... 相似文献
35.
鉴于航空机轮加载试验过程中,要求上位机测控软件能够即时向下位机下达控制命令并且能够实时采集下位机上传的大量现场数据,给出了一种基于DataSocket技术和OPC协议的实时网络通信方法;针对程序执行过程中常出现的响应阻塞问题,结合LabWin-dows/CVI的多线程机制论述了一种多任务并发执行的方法;经过反复测试试验,由此所构建的上位机软件响应性能良好,其网络通信传输速率快、实时性高。 相似文献
36.
Journal of Porous Materials - Nitrogen and oxygen co-doped hierarchical porous carbons (NOPCs) is prepared by the pyrolysis of polyethylene glycol-200 (PEG) and triazine carbon forming agent (CFA)... 相似文献
37.
Magnetotactic bacteria (MTB) are one kind of bacteria with magnetic particles called magnetosomes in their bodies. These particles often connect together like a chain. The MTB move toward the ideal living conditions under the interaction between magnetic field produced by the magnetic particles chain and that of the earth. In the paper, a new magnetic bacteria algorithm based on power spectrum (PSMBA) for optimization is proposed. The candidate solutions are decided by power spectrum in the algorithm. It mainly includes four steps: power spectrum calculation, bacteria swimming, bacteria rotation and bacteria replacement. The effect of swimming schemes and parameter settings on the performance of PSMBA is studied. And it is compared with GA, PSO and its variants and some other optimization algorithms on 25 benchmark functions including CEC2005. The simulation results show that PSMBA has better performance on most of the problems than most of the compared algorithms. 相似文献
38.
原始树突状细胞算法(DCA)的离线分析过程,将会导致时间差异,从而产生假警报,增加了虚警率,也会导致攻击的成功发生,这对一个人侵检测系统来说是致命的。因此,文中的目的就是在不影响检测精度的前提下提高检测速度。于是文中提出了分片思想的在线分析组件与DCA相集成的方法,即根据抗原采样数量或者时间将一系列已处理的信息分割成为更小的部分,使得每个分片独立地进行实时的、周期性的分析,这样在每个分片内的入侵攻击就能及时地被识别出来。文中给出了DCA在线分析模块的伪代码描述,并且将其应用于SYN端口扫描的检测实验中。结果表明,DCA在线分析模块在不影响检测精度的前提下有效地提高了检测速度。 相似文献
39.
本工作研究了化合物13-SO_3Na-DDHA在不同pH的缓冲溶液中的电化学氧化还原行为.实验证明:化合物中羰基的还原电位与pH之间存在线性关系,其直线的斜率为60mV/pH.并证明了此过程为一步两电子、两质子还原过程:Q+2H ̄++2e=QH_2.DMF作为非质子溶剂,具有很好的稳定自由基的作用.向缓冲溶液中加入DMF后,化合物13-SO_3Na-DDHA为两步单电子还原过程,相应溶液中的光诱导电子转移吸收光谱证实了以上电化学的结果. 相似文献
40.
This paper seeks to enhance network survivability under a disaster and reduce the expected post-disaster response time for transportation networks through pre-disaster investment decisions. The planning focuses on determining the links of the network to strengthen through investment under two types of uncertainties: the disaster characteristics, and the surviving network under each disaster. A bi-level stochastic optimization model is proposed for this problem, in which link investment decisions are made at the upper level to enhance the network survivability subject to a budget constraint such that the expected post-disaster response time is minimized at the lower level. A two-stage heuristic algorithm is proposed to obtain effective solutions efficiently. The numerical experiments indicate that the proposed heuristic algorithm converges to a fixed point representing a feasible solution, within an acceptable tolerance level, of the bi-level stochastic optimization model which is an effective solution under disasters of moderate severity. Parametric and sensitivity analyses reinforce the need for a holistic approach that integrates multiple relevant considerations to determine the link investment decisions. 相似文献