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1.
Photon emission of phagocytes in relation to stress and disease.   总被引:1,自引:0,他引:1  
E M Lilius  P Marnila 《Experientia》1992,48(11-12):1082-1091
Phagocytes, the first-line cells of the body's defence mechanisms against invading pathogens, kill microorganisms by means of lysosomal degradative enzymes and highly toxic reactive oxygen intermediates. The reactive oxygen compounds are produced, in a process called the 'respiratory burst', by the NADPH oxidase complex in plasma membranes, and by myeloperoxidase in phagolysosomes after degranulation. These processes generate electronically excited states which, on relaxation, emit photons, giving rise to phagocyte chemiluminescence (CL). This paper describes the conditions for the measurement of CL, and reviews the activity of phagocytes from individuals undergoing stress or disease. The capability of phagocytes to emit photons reflects remarkably well the pathophysiological state of the host. In many cases even the magnitude of the stress, the presence of a pathogen in the body, or the activity of the disease can be estimated. Physiological changes, e.g. in the reproductive cycle, can also be predicted.  相似文献   
2.
国际空间站和欧洲核子中心的大型强子对撞机 (LHC)计划目前都面临资金上的窘境 ;……除了对项目 (尤其是耗资巨大的项目 )预算的科学化 ,管理的科学化在其中尤显重要  相似文献   
3.
Summary The authors show the antibiotic activity of water-insoluble salts of hydrosoluble antibiotics in the case of penicillin G (salts of iron, copper, silver, gold, and uranium) and streptomycin (oleate).  相似文献   
4.
I offer a reply to criticisms of the Strong Programme presented by Stephen Kemp who develops some new lines of argument that focus on the ‘monism’ of the programme. He says the programme should be rejected for three reasons. First, because it embodies ‘weak idealism’, that is, its supporters effectively sever the link between language and the world. Second, it challenges the reasons that scientists offer in explanation of their own beliefs. Third, it destroys the distinction between successful and unsuccessful instrumental action. Kemp is careful to produce quotations from the supporters of the programme as evidence to support his case. All three points deserve and are given a detailed response and the interpretation of the quoted material plays a significant role in the discussion. My hope is that careful exegesis will offset the numerous misinterpretations that are current in the philosophical literature. Particular attention is paid to what is said about the normative standards involved in the application of empirical concepts. The operation of these standards in the face of the negotiability of all concepts is explored and misapprehensions on the topic are corrected. The work of Wittgenstein, Popper, Kuhn and Hesse is used to illustrate these themes.  相似文献   
5.
Duhem’s concept of ‘good sense’ is central to his philosophy of science, given that it is what allows scientists to decide between competing theories. Scientists must use good sense and have intellectual and moral virtues in order to be neutral arbiters of scientific theories, especially when choosing between empirically adequate theories. I discuss the parallels in Duhem’s views to those of virtue epistemologists, who understand justified belief as that arrived at by a cognitive agent with intellectual and moral virtues, showing how consideration of Duhem as a virtue epistemologist offers insights into his views, as well as providing possible answers to some puzzles about virtue epistemology. The extent to which Duhem holds that the intellectual and moral virtues of the scientist determine scientific knowledge has not been generally noticed.  相似文献   
6.
1 Results Acid-doped polybenzimidazoles[1] are particularly appealing because of high proton conductivity with no or low humidification and promising fuel cells performances. PBI, in fact, contains basic functional groups which can easily interact with strong oxo-acids, such as H3PO4 and H2SO4. The acid partially protonates the polymer and partially is freely dispersed in the polymer backbone, so allowing proton migration via Grotthuss mechanism along the anionic chains[2]. Anyway, a technological limit...  相似文献   
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