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Ohne ZusammenfassungZitierte Literatur Archive Hist. Ex. Sc. Archive for history of exact sciences; New York - Atti Bologna Atti del IV. Congresso Internazionale dei Matematici Bologna 1928 - Atti Roma Atti del VI. Congresso Internazionale dei Matematici Roma 1908 - C. R. Comptes rendus de l'Académie des sciences, Paris - Encyklop. Encyklopädie der mathematischen Wissenschaften; Leipzig, Teubner - Hist. Math. Historia Mathematica; Toronto/New York - Ist.-mat. issl. Istoriko-matematieskie issledovanija; Moskva - Jahresbericht DMV Jahresbericht der Deutschen Mathematikervereinigung - Kongreß Moskau 1971 Russische Übersetzung eines Vortrages, gehalten auf dem XIII. Internationalen Kongreß für Wissenschaftsgeschichte Moskau 1971 - Math. Ann. Mathematische Annalen (begründet von A. Clebsch) - NTM Zeitschrift für Geschichte von Naturwissenschaft, Technik und Medizin; Leipzig Vorgelegt von M. Kline  相似文献   
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Aspergillus fumigatus is exceptional among microorganisms in being both a primary and opportunistic pathogen as well as a major allergen. Its conidia production is prolific, and so human respiratory tract exposure is almost constant. A. fumigatus is isolated from human habitats and vegetable compost heaps. In immunocompromised individuals, the incidence of invasive infection can be as high as 50% and the mortality rate is often about 50% (ref. 2). The interaction of A. fumigatus and other airborne fungi with the immune system is increasingly linked to severe asthma and sinusitis. Although the burden of invasive disease caused by A. fumigatus is substantial, the basic biology of the organism is mostly obscure. Here we show the complete 29.4-megabase genome sequence of the clinical isolate Af293, which consists of eight chromosomes containing 9,926 predicted genes. Microarray analysis revealed temperature-dependent expression of distinct sets of genes, as well as 700 A. fumigatus genes not present or significantly diverged in the closely related sexual species Neosartorya fischeri, many of which may have roles in the pathogenicity phenotype. The Af293 genome sequence provides an unparalleled resource for the future understanding of this remarkable fungus.  相似文献   
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Summary The isolation of anthocyanin-producing and non-producing cell lines of tissue cultures ofDaucus carota is described. Those clones which are able to synthesize anthocyanins do this in dark only if there is an auxin like 2,4-D, IAA or NAA present. In light no supplementary auxin is necessary for anthocyanin production. It is assumed that there might be relations between auxin and light-induced anthocyanin biosynthesis.  相似文献   
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The genome of the human immunodeficiency virus is highly prone to recombination, although it is not obvious whether recombinants arise infrequently or whether they are constantly being spawned but escape identification because of the massive and rapid turnover of virus particles. Here we use fluorescence in situ hybridization to estimate the number of proviruses harboured by individual splenocytes from two HIV patients, and determine the extent of recombination by sequencing amplified DNA from these cells. We find an average of three or four proviruses per cell and evidence for huge numbers of recombinants and extensive genetic variation. Although this creates problems for phylogenetic analyses, which ignore recombination effects, the intracellular variation may help to broaden immune recognition.  相似文献   
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The I kappa B kinase (IKK), consisting of the IKK1 and IKK2 catalytic subunits and the NEMO (also known as IKK gamma) regulatory subunit, phosphorylates I kappa B proteins, targeting them for degradation and thus inducing activation of NF-kappa B (reviewed in refs 1, 2). IKK2 and NEMO are necessary for NF-kappa B activation through pro-inflammatory signals. IKK1 seems to be dispensable for this function but controls epidermal differentiation independently of NF-kappa B. Previous studies suggested that NF-kappa B has a function in the growth regulation of epidermal keratinocytes. Mice lacking RelB or I kappa B alpha, as well as both mice and humans with heterozygous NEMO mutations, develop skin lesions. However, the function of NF-kappa B in the epidermis remains unclear. Here we used Cre/loxP-mediated gene targeting to investigate the function of IKK2 specifically in epidermal keratinocytes. IKK2 deficiency inhibits NF-kappa B activation, but does not lead to cell-autonomous hyperproliferation or impaired differentiation of keratinocytes. Mice with epidermis-specific deletion of IKK2 develop a severe inflammatory skin disease, which is caused by a tumour necrosis factor-mediated, alpha beta T-cell-independent inflammatory response that develops in the skin shortly after birth. Our results suggest that the critical function of IKK2-mediated NF-kappa B activity in epidermal keratinocytes is to regulate mechanisms that maintain the immune homeostasis of the skin.  相似文献   
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Reinhard CT  Planavsky NJ 《Nature》2011,474(7349):E1-2; discussion E4-5
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Neuronal exocytosis is catalysed by the SNAP receptor protein syntaxin-1A, which is clustered in the plasma membrane at sites where synaptic vesicles undergo exocytosis. However, how syntaxin-1A is sequestered is unknown. Here we show that syntaxin clustering is mediated by electrostatic interactions with the strongly anionic lipid phosphatidylinositol-4,5-bisphosphate (PIP2). Using super-resolution stimulated-emission depletion microscopy on the plasma membranes of PC12 cells, we found that PIP2 is the dominant inner-leaflet lipid in microdomains about 73 nanometres in size. This high accumulation of PIP2 was required for syntaxin-1A sequestering, as destruction of PIP2 by the phosphatase synaptojanin-1 reduced syntaxin-1A clustering. Furthermore, co-reconstitution of PIP2 and the carboxy-terminal part of syntaxin-1A in artificial giant unilamellar vesicles resulted in segregation of PIP2 and syntaxin-1A into distinct domains even when cholesterol was absent. Our results demonstrate that electrostatic protein-lipid interactions can result in the formation of microdomains independently of cholesterol or lipid phases.  相似文献   
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