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581.
Nicolai Miosge Werner G?tz Takako Sasaki Mon-Li Chu Rupert Timpl Rainer Herken 《The Histochemical journal》1996,28(2):109-116
Summary Fibulin-1 and fibulin-2, two recently identified extracellular matrix proteins with a homologous domain structure, are known
to bind various extracellular ligands and calcium. In this study, they have been localized at the light microscopical level
in human embryos of gestational weeks 4–10, using polyclonal antibodies. Identical localization patterns were observed for
the two fibulins in most of the tissues. In the heart, the endocardial cushion tissue and endocardium, but not the myocardium,
were stained, as were the basement membrane zones and adventitia of blood vessels. Staining was also observed in the perichondrium
and calcifying regions of developing bones. Moreover, reactions occurred with the gut subepithelium and epithelial basement
membranes of the skin. Differences in staining patterns, however, were observed in various neural structures. Fibulin-1 was
prominent in the matrix of the leptomeningeal anlage, in basement membranes of the neuroepithelium and the perineurium of
peripheral nerves. Fibulin-2 was detected primarily within the neuropithelium, spinal ganglia and peripheral nerves. The early
embryonic expression of both fibulins indicates specific roles during organ development and, in particular, involvement in
the differentiation of heart, skeletal and neuronal structures. 相似文献
582.
Ilka M. Kureck Beate Nicolai Evelien Jongepier Susanne Foitzik 《Molecular ecology》2013,22(6):1759-1760
583.
Volker Nicolai 《Oecologia》1986,69(1):148-160
Summary The thermal properties of four different types of bark were investigated on twentyfour central European tree species using thermocouples. Tree species with white bark avoid overheating of their surface by reflection of the radiation. Species with fissured and scaly barks shade inner parts of their bark. Some tree species with fissured barks show high insulation across the bark. Smooth and thin barks show no adaptation to avoid overheating. These tree species (in central Europe e.g. Fagus sylvatica) have to form closed stands and are not able to occur in open stands as tree species with structured or white bark types.The arthropod fauna of the same bark types was studied on six tree species using three collecting methods. The microclimate on the bark determines the number per cm2 of some species, some are active during winter, and other tend to aptery and reproduce parthenogenetically. On smooth bark one species dominates, whereas a highly diverse fauna lives on fissured barks. The occurrence of species on bark is determined by the microstructure, microclimate and consistence of the epiphyts. If tree species alter within forest ecosystems the dominant species on bark will persist. Specialists of fissured barks will die out if tree species with smooth bark (Fagus sylvatica) form the central European forest. 相似文献
584.
585.
Milke Lars Aschenbrenner Jennifer Marienhagen Jan Kallscheuer Nicolai 《Applied microbiology and biotechnology》2018,102(4):1575-1585
Applied Microbiology and Biotechnology - Plants synthesize several thousand different polyphenols of which many have the potential to aid in preventing or treating cancer, cardiovascular, and... 相似文献
586.
Addition of chloroazide to 3,4,6-tri-O-acetyl-1,5-anhydro-2-deoxy-d-lyxo- (1) and -d-arabino-hex-1-enitol (2) under u.v. irradiation proceeds regio- and stereo-selectively yielding mainly O-acetyl derivatives of 2-azido-2-deoxy-d-galactopyranose and -d-glucopyranose, respectively. 3,4,6-Tri-O-acetyl-2-chloro-2-deoxy-α-d-galactopyranosyl azide and 3,4,6-tri-O-acetyl-2-azido-2-deoxy-α-d-talopyranose (from 1), and 1,3,4,6-tetra-O-acetyl-2-chloro-2-deoxy-α-d-glucopyranosyl azide and 1,3,4,6-tetra-O-acetyl-2-azido-2-deoxy-α-d-mannopyranose (from 2) are byproducts. 1,5-Anhydro-3,4,6-tri-O-benzyl-2-deoxy-d-lyxo- and -d-arabino-hex-1-enitol reacted more rapidly with chloroazide, to give, under irradiation, derivatives of 2-azido-2-deoxy-d-galactose and -d-glucose, respectively. However, reaction in the dark gave mainly O-benzyl derivatives of 2-chloro-2-deoxy-α-d-galacto- and -α-d-glucopyranosyl azide. The difference between the products obtained may depend on the existence of two parallel processes, one radical (under irradiation), and the other ionic (reaction in the dark). 相似文献
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588.