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71.
Zusammenfassung Dank einer neuen Anwendung von Lymphknotenextrakten (statt Röntgenextrakten, Corticosteroiden, Antilymphozytenserum usw.) wird eine erhebliche Reduktion der immunologischen Reaktion erzielt, wenn die Tiere mit diesen Extrakten vorbehandelt und gleichzeitig mit Antigenen behandelt werden.

This investigation was supported in part by U.S.P.H.S. Research Grant No. CA-02624 from National Cancer Institute; and in part by an institutional grant to Detroit Institute of Cancer Research from United Foundation of greater Detroit allocated through Michigan Cancer Foundation and the Detroit General Hospital Research Corporation, and Newaygo County Cancer Society.  相似文献   
72.
Fungal disease is an increasing problem in both agriculture and human health. Treatment of human fungal disease involves the use of chemical fungicides, which generally target the integrity of the fungal plasma membrane or cell wall. Chemical fungicides used for the treatment of plant disease, have more diverse mechanisms of action including inhibition of sterol biosynthesis, microtubule assembly and the mitochondrial respiratory chain. However, these treatments have limitations, including toxicity and the emergence of resistance. This has led to increased interest in the use of antimicrobial peptides for the treatment of fungal disease in both plants and humans. Antimicrobial peptides are a diverse group of molecules with differing mechanisms of action, many of which remain poorly understood. Furthermore, it is becoming increasingly apparent that stress response pathways are involved in the tolerance of fungi to both chemical fungicides and antimicrobial peptides. These signalling pathways such as the cell wall integrity and high-osmolarity glycerol pathway are triggered by stimuli, such as cell wall instability, changes in osmolarity and production of reactive oxygen species. Here we review stress signalling induced by treatment of fungi with chemical fungicides and antifungal peptides. Study of these pathways gives insight into how these molecules exert their antifungal effect and also into the mechanisms used by fungi to tolerate sub-lethal treatment by these molecules. Inactivation of stress response pathways represents a potential method of increasing the efficacy of antifungal molecules.  相似文献   
73.
Summary In the brain wall of different vertebrate species, ependymal cells of different type occur. These cells possess protuberances which protrude into the ventricle.Although cytologically these structures are all variations of one theme, they must at present be interpreted in different ways as regards function.Probably these cell types form a complex system for the regulation of the cerebrospinal fluid. It remains possible that one or more of these cell types act as light receptors.  相似文献   
74.
Epithelial antimicrobial peptides: innate local host response elements   总被引:23,自引:0,他引:23  
Multicellular organisms have to survive in an environment laden with numerous microorganisms, which represent a potential hazard to life. Different strategies have been developed to ward off infections by preventing microorganisms from entering surfaces and by preventing the attack of microorganisms that have already entered the epithelia. Therefore, it is not surprising that epithelia are equipped with various antimicrobial substances that act rapidly to kill a broad range of microorganisms. This review summarizes our present knowledge about epithelial peptide antibiotics produced in plants, invertebrates, and vertebrates including humans. There is now strong evidence that in addition to constitutively secreted peptide antibiotics, others are induced upon contact with microorganisms or by proinflammatory cytokines. beta-Defensins represent one family of vertebrate antimicrobial peptides, members of which are inducible and have recently been identified in humans. The defensin-characteristic local expression pattern may indicate that specialized surfaces express a characteristic surface antimicrobial peptide pattern that might define the characteristic microflora as well as the density of microorganisms present on the surface.  相似文献   
75.
My review of Ike Kamphof’s “Webcams to Save Nature: Online Space as Affective and Ethical Space” focuses on the question how the engagement of the spectator of the described websites is temporally structured and how the discrepancy between the instantaneity of affective response and the duration of moral engagement is solved. I propose to draw on Alexander Nehamas’ philosophy of beauty as an in-between, bringing affect and ethics closer together.  相似文献   
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Human skin is permanently exposed to microorganisms, but rarely infected. One reason for this natural resistance might be the existence of a ‘chemical barrier’ consisting in constitutively and inducibly produced antimicrobial peptides and proteins (AMPs). Many of these AMPs can be induced in vitro by proinflammatory cytokines or bacteria. Apart from being expressed in vivo in inflammatory lesions, some AMPs are also focally expressed in skin in the absence of inflammation. This suggests that non-inflammatory stimuli of endogenous and/or exogenous origin can also stimulate AMP synthesis without inflammation. Such mediators might be ideal ‘immune stimulants’ to induce only the innate antimicrobial skin effector molecules without causing inflammation. Received 9 August 2005; received after revision 21 October 2005; accepted 16 November 2005  相似文献   
79.
Phytanic acid is a branched-chain fatty acid that accumulates in a variety of metabolic disorders. High levels of phytanic acid found in patients can exceed the millimolar range and lead to severe symptoms. Degradation of phytanic acid takes place by α-oxidation inside the peroxisome. A deficiency of its breakdown, leading to elevated levels, can result from either a general peroxisomal dysfunction or from a defect in one of the enzymes involved in α-oxidation. Research on Refsum disease, belonging to the latter group of disorders and characterized by a deficiency of the first enzyme of α-oxidation, has extended our knowledge of phytanic acid metabolism and pathology of the disease greatly over the past few decades. This review will centre on this research on phytanic acid: its origin, the mechanism by which its α-oxidation takes place, its role in human disease and the way it is produced from phytol. Received 4 October 2005; received after revision 24 February 2006; accepted 26 April 2006  相似文献   
80.
Hemoglobin is widely used as an inhibitor of EDRF effects. Hemoglobin contracts pig coronary arteries in vitro. However, during this contraction, effects of substance P and bradykinin which act via the EDRF are not inhibited. This means that the hemoglobin contraction is not caused by inhibition of the EDRF. This contraction is caused by a substance released from the endothelium, and by eicosano?ds released from the smooth muscles.  相似文献   
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