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11.
Jason Iles Raminta Zmuidinaite Christoph Sadee Anna Gardiner Jonathan Lacey Stephen Harding Jernej Ule Debra Roblett Jonathan Heeney Helen Baxendale Ray K. Iles 《International journal of molecular sciences》2022,23(8)
The immune response to SARS-CoV-2 infection requires antibody recognition of the spike protein. In a study designed to examine the molecular features of anti-spike and anti-nucleocapsid antibodies, patient plasma proteins binding to pre-fusion stabilised complete spike and nucleocapsid proteins were isolated and analysed by matrix-assisted laser desorption ionisation–time of flight (MALDI-ToF) mass spectrometry. Amongst the immunoglobulins, a high affinity for human serum albumin was evident in the anti-spike preparations. Careful mass comparison revealed the preferential capture of advanced glycation end product (AGE) forms of glycated human serum albumin by the pre-fusion spike protein. The ability of bacteria and viruses to surround themselves with serum proteins is a recognised immune evasion and pathogenic process. The preference of SARS-CoV-2 for AGE forms of glycated serum albumin may in part explain the severity and pathology of acute respiratory distress and the bias towards the elderly and those with (pre)diabetic and atherosclerotic/metabolic disease. 相似文献
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主蒸汽压力是电厂热工过程控制中的重要参数,由于锅炉燃烧工况变化较大,主汽压对象模型具有不确定性,常规控制方法很难得到预期的控制效果。为提高系统控制品质,提出了主汽压系统的H∞混合灵敏度设计方法,给出了选择加权函数的具体方法,采用MATLAB软件进行仿真计算,得到H∞最优控制器。仿真结果表明,在对象模型参数发生较大变化时,与常规PID调节方法相比,H∞最优控制器能使主汽压控制系统具有良好的鲁棒稳定性和动态性能。 相似文献
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Marijuana, Cannabis sativa, elicits a variety of effects in experimental animals and humans. Delta-9-tetrahydrocannabinol (THC) is the major psychoactive component in marijuana. This substance has been shown, also, to be immunosuppressive and to decrease host resistance to bacterial, protozoan, and viral infections. Macrophages, T lymphocytes, and natural killer cells appear to be major targets of the immunosuppressive effects of THC. Definitive data which directly link marijuana use to increased susceptibility to infection in humans currently is unavailable. However, cumulative reports indicating that THC alters resistance to infection in vitro and in a variety of experimental animals support the hypothesis that a similar effect occurs in humans. 相似文献
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The effects of the rodent hepatocarcinogens clofibric acid and diprofibrate on the activity of the peroxisomal fatty acyl-CoA oxidase, DNA synthesis, and apoptosis were compared in cultured rat and human hepatocytes. Rat hepatocytes expressed a 10-fold greater level of the peroxisomal fatty acyl-CoA oxidase compared to human hepatocytes. At the highest concentration (1.0 mM), both drugs induced a two- to threefold increase in this enzyme activity in both rat and human hepatocytes. Ciprofibrate (0.1 and 0.2 mM) caused a twofold increase in DNA synthesis in rat hepatocytes, whereas clofibric acid had no effect on DNA synthesis in these cells. In contrast, increasing concentrations of both clofibric acid and ciprofibrate produced inhibition of DNA synthesis in human hepatocytes. By using the terminal transferase dUTP-biotin nick end labeling technique, it was observed that 0.1 and 0.2 mM clofibric acid and ciprofibrate suppressed transforming growth factor-beta (TGF beta)-induced apoptosis by 50% in rat hepatocytes, but they had no effect on TGF beta-induced apoptosis in human hepatocytes. Although clofibric acid and ciprofibrate diminished TGF beta-induced apoptosis, they had no effect on the basal apoptotic levels in the rat hepatocyte cultures. However, both drugs significantly increased the percent of apoptotic cells in the human hepatocyte cultures. It is concluded that primary rat and human hepatocyte cultures respond differently to peroxisome proliferators. The differences in effects on DNA synthesis and apoptosis support the hypothesis that human liver cells are refractory to peroxisome proliferator-induced hepatocarcinogenesis. 相似文献
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The paper considers the problem of sequential estimation of the mean survival time using randomly right censored data when the loss is measured by the sum of the squared error of estimation and the cost of observations made with per unit cost c being constant. The sequential estimator defined here is shown to be asymptotically risk efficient and asymptotically normal as c 4 ↓ 0 under certain regularity conditions. These conditions are shown to be satisfied by a wide variety of survival distributions and censoring distributions. Furthermore, they hold trivially when the mean survival experience over a finite interval [0,T], T < ∞, is of interest. 相似文献
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红曲与红曲色素的研究进展 总被引:7,自引:0,他引:7
阐述了红曲与红曲色素的各类,生产工艺及应用,介绍了红曲与红曲色素的现状和市场开发前景。 相似文献
20.
采用磷酸硼对木材进行改性处理,测定了处理后试材的阻燃性、抗流失性、吸湿性、力学性能.研究结果表明,磷酸硼处理后试材,吸药量达到20.47 kg/m3以上时,垂直燃烧实验可达到到F-0级水平;通过灼烧实验,磷酸硼处理的木粉在500℃灼烧时残留率可达到97.997%;此改性剂具有较好阻燃性能和一定的抗流失性,常压下磷酸硼处理的樟子松试件LRV为50.28%;木材顺纹抗压强度平均下降了 8.67%,无明显变化;木材抗弯曲压强度平均下降了 27.95%.但磷酸硼阻燃剂在高湿条件下有一定的吸湿性,使用性能有待改进,并应注意采取防护措施. 相似文献