排序方式: 共有47条查询结果,搜索用时 718 毫秒
41.
T. Aigner E. Reichenberger W. Bertling T. Kirsch H. Stöß K. von der Mark 《Virchows Archiv. B, Cell pathology including molecular pathology》1993,63(1):205-211
Type X collagen is a short chain, non-fibrilforming collagen synthesized primarily by hypertrophic chondrocytes in the growth
plate of fetal cartilage. Previously, we have also identified type X collagen in the extracellular matrix of fibrillated,
osteoarthritic but not in normal articular cartilage using biochemical and immunohistochemical techniques (von der Mark et
al. 1992 a). Here we compare the expression of type X with types I and II collagen in normal and degenerate human articular
cartilage by in situ hybridization. Signals for cytoplasmic α1(X) collagen mRNA were not detectable in sections of healthy
adult articular cartilage, but few specimens of osteoarthritic articular cartilage showed moderate expression of type X collagen
in deep zones, but not in the upper fibrillated zone where type X collagen was detected by immunofluorescence. This apparent
discrepancy may be explained by the relatively short phases of type X collagen gene activity in osteoarthritis and the short
mRNA half-life compared with the longer half-life of the type X collagen protein. At sites of newly formed osteophytic and
repair cartilage, α1(X) mRNA was strongly expressed in hypertrophic cells, marking the areas of endochondral bone formation.
As in hypertrophic chondrocytes in the proliferative zone of fetal cartilage, type X collagen expression was also associated
with strong type II collagen expression. 相似文献
42.
Markus Bertling 《Pal?ontologische Zeitschrift》1992,66(1-2):177-185
Burrowing traces in internal moulds of molluscs are described asArachnostega gastrochaenae n. ichnog. n. ichnosp. Currently, the ichnogenus is only known from the Late Jurassic and Recent of Northern Germany. The synecology of its polychaete producers is discussed in detail: they were probably opportunistic detritus-feeders and have to be regarded as infaunal coelobites. The tracemakers were not part of an ecological succession because their activity was facilitated by a sedimentation event. They weakened the skeletal frame but rapid cementation and encrusters inhibited them. Finally, aspects of biostratinomy and fossil diagenesis are sketched. 相似文献
43.
Maga Daniel Galafton Christina Blömer Jan Thonemann Nils Özdamar Aybüke Bertling Jürgen 《The International Journal of Life Cycle Assessment》2022,27(3):469-491
The International Journal of Life Cycle Assessment - Products made of plastic often appear to have lower environmental impacts than alternatives. However, present life cycle assessments (LCA) do... 相似文献
44.
Radek Mikuláš Jesper Milàn Jorge F. Genise Markus Bertling Richard G. Bromley 《Ichnos》2020,27(3):284-289
AbstractAn insect boring of unique shape is described from a lignitic layer within the Early Cretaceous (Berriasian) Skyttegård Member of the Rabekke Formation on Bornholm. Morphologically it cannot be compared to any modern or fossil wood borings, although some structures are reminiscent of Scolytidae, Platypodidae and Lymexylonidae. Most probably, however, the tracemaker was a female fungus-farming beetle, thus producing an agrichnion. 相似文献
45.
Enni Bertling Peter Blaesse Patricia Seja Elena Kremneva Gergana Gateva Mari A Virtanen Milla Summanen Inkeri Spoljaric Pavel Uvarov Michael Blaesse Ville O Paavilainen Laszlo Vutskits Kai Kaila Pirta Hotulainen Eva Ruusuvuori 《EMBO reports》2021,22(4)
Intracellular pH is a potent modulator of neuronal functions. By catalyzing (de)hydration of CO2, intracellular carbonic anhydrase (CAi) isoforms CA2 and CA7 contribute to neuronal pH buffering and dynamics. The presence of two highly active isoforms in neurons suggests that they may serve isozyme‐specific functions unrelated to CO2‐(de)hydration. Here, we show that CA7, unlike CA2, binds to filamentous actin, and its overexpression induces formation of thick actin bundles and membrane protrusions in fibroblasts. In CA7‐overexpressing neurons, CA7 is enriched in dendritic spines, which leads to aberrant spine morphology. We identified amino acids unique to CA7 that are required for direct actin interactions, promoting actin filament bundling and spine targeting. Disruption of CA7 expression in neocortical neurons leads to higher spine density due to increased proportion of small spines. Thus, our work demonstrates highly distinct subcellular expression patterns of CA7 and CA2, and a novel, structural role of CA7. 相似文献
46.
47.
Markus Bertling 《Pal?ontologische Zeitschrift》1994,68(3-4):419-435
In the Late Oxfordian Korallenoolith of northern Germany, eight bryozoan taxa encrusting corals have been found, six of which had not been previously recorded in the area. In most cases, they can only be described using open nomenclature since the gonozooids are not known and the type material of existing species is too poorly preserved. “Stationary” bereniciform bryozoans were relatively good competitors adapted to a predictable environment. For this reason they thrived in the calm-water facies. However, the environment was disturbed frequently as proved by the joint occurrence with Stomatoporidae. These “mobile” taxa could grow fast on strongly three-dimensional surfaces, thus being able to survive even in highly agitated facies by escaping into cryptic habitats. The distribution of individual taxa is thus governed by the type and frequency of perturbations of their habitats. Bryozoans had a binding function in the fauna related to corals. Because of their low number and poor coverage, they mostly had little importance, however. This is due to the high water energy or high rate of sedimentation, which characterized the environments of the sampled localities. Thus, ideal habitats were not available. Nevertheless, the characteristic bryozoan associations of the European Jurassic became established together with typical associated faunal elements. 相似文献