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71.
Zusammenfassung Bei der experimentellen allergischen Neuritis verlassen die Lymphozyten das zirkulierende Blut der Venolen der peripheren Nerven, indem sie eher durch die als zwischen den Endothelzellen austreten. Der Durchtritt durch das Zytoplasma der Endothelzellen ist ein Beispiel von Emperipolesis.

Supported by parts by NIH grant No. NB-03789-05, Inst. grant No. FRO5486-04, and a grant from the Swedish Medical Research Council. I thank Mr.L. Cherkas for help with the photography.  相似文献   
72.
Safety of patients in anesthesia has always been one of the major concerns of the anesthetist. It is clear from studies of safety in general that many accidents and critical incidents occur as the result of latent systemic failures to which a great number of factors contribute (Reason, 1990). An ideal way to approach this problem would be within a systemic framework, such as teleonics, developed by Járos and his co-workers (Cloete, 1999; Járos and Cloete, 1987, 1993). In this framework the events and procedures in anesthesia are considered to be part of a very complex network of process systems (teleons). It is postulated that teleonic uncertainty (telentropy) in this complex network is a factor that might lead to accidents. In a previous paper presented to the World Congress at Toronto in 2000, the principles of teleonics were described in a mathematico symbolic way (Horváth et al., 2000). This paper contains selected examples of application of these principles to the identification of possible systemic causes of accidents in anesthesia.  相似文献   
73.
Host tree unsuitability recognized by pine shoot beetles in flight   总被引:2,自引:0,他引:2  
Summary In spring, the landing rate of flying European pine shoot beetles,Tomicus piniperda L., on injured Scots pine diminishes as colonization continues. This is due to olfactory cues that indicate progressive host degradation. Verbenone was shown to play a role in the beetle's recognition of this unsuitability of a formerly suitable host, since the compound was increasingly released from colonized tree sections as they aged, but not from uninfested sections. Also, the release of verbenone at natural rates in the forest inhibited the attraction of beetles to host monoterpenes.  相似文献   
74.
Summary It has been found that cyclisation of -halogenated -naphthalene-thioglycolic acids can occur in -position with the elimination of the halogen. The influence of the temperature and of a further substituent (halogen) in the second nucleus are discussed.  相似文献   
75.
Summary The terminally unsaturated hydrocarbons of the defensive secretion ofTribolium confusum are biosynthesized from fatty acids by oxidative decarboxylation. The process involves an enantiospecific cleavage of the C–H bond of thepro-(S) C(3)–H atom and simultaneous decarboxylation of the acid into an 1-alkene and carbon dioxide via ananti-periplanar transition state geometry (anti-elimination). The stereochemistry of this biotranformation is identical in all respects with the same reaction in higher plants. The mechanism seems to be of general importance for the biosynthesis of many vinylic substructures of natural products from oxygen-containing precursors.  相似文献   
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Schollwöck U 《Nature》2005,437(7062):1204
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To identify susceptibility loci for meningioma, we conducted a genome-wide association study of 859 affected individuals (cases) and 704 controls with validation in two independent sample sets totaling 774 cases and 1,764 controls. We identified a new susceptibility locus for meningioma at 10p12.31 (MLLT10, rs11012732, odds ratio = 1.46, P(combined) = 1.88 × 10(-14)). This finding advances our understanding of the genetic basis of meningioma development.  相似文献   
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