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41.
Summary Normal mouse spleen cells take up in vitro radioactively labeled immune RNA. RNA taken up is present in nuclei, polysomes, membranes and cytoplasm. About 20–40% of immune RNA is nonspecifically associated with cell surface. 45% of RNA taken up is degraded and reutilized inside the cells within 2 hours.This work was supported by the Polish Academy of Sciences within the project 09.7.4.1.1.  相似文献   
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The phosphorylation of microtubular proteins isolated by reassembly in vitro from slices of guinea-pig cerebral cortex labelled with [32P]orthophosphate was investigated. Under the conditions tested, both and the alpha and beta forms of tubulin contained metabolically-active P which accounted for about one third of the total 32P incorporated into protein; the remaining protein-bound 32P was associated with 3-4 minor high MW components co-purifying with tubulin during two cycles of assembly-disassembly. Microtubular protein prepared in this way contained approx. 0.8 mol of alkalilabile P/mol of tubulin dimer (M.W. 110,000). In vitro studies showed that reassembled microtubular protein preparations catalysed the incorporation of up to 0.55 mol of P/mol of tubulin dimer during incubation with Mg2+ and [gamma 32P]ATP. The reaction was linear during the first 30 min of incubation at 37 degrees C. Cyclic AMP (10 microM, final concentration) caused a transient increase in the initial rates of tubulin phosphorylation. Little label was incorporated into the minor high M.W. components under these conditions. The in vitro phosphorylation of microtubular protein increased in a non-linear manner with respect to protein concentration: this was in contrast to earlier experiments showing linear kinetics when chromatographically isolated tubulin was tested for intrinsic kinase activity. Isolated microtubular protein preparations bound [3H]GTP, [3H]ATP and to a lesser extent, [3H]cyclic AMP, and exhibited Ca(2+)-ATPase activity (up to 60 pmol Pi released min/mg protein at 37 degrees C).  相似文献   
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A subsystem impactor test for pedestrian lower limb injury evaluation has been brought in China New Car Assessment Protocol(CNCAP).Concerning large anthropometr...  相似文献   
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Background: Ehlers-Danlos syndrome (EDS) is a common non-inflammatory, congenital connective tissue disorder. Classical type (cEDS) EDS is one of the more common forms, typically caused by mutations in the COL5A1 and COL5A2 genes, though causative mutations in the COL1A1 gene have also been described. Material and methods: The study group included 59 patients of Polish origin, diagnosed with cEDS. The analysis was performed on genomic DNA (gDNA) with NGS technology, using an Illumina sequencer. Thirty-five genes related to connective tissue were investigated. The pathogenicity of the detected variants was assessed by VarSome. Results: The NGS of 35 genes revealed variants within the COL5A1, COL5A2, COL1A1, and COL1A2 genes for 30 of the 59 patients investigated. Our panel detected no sequence variations for the remaining 29 patients. Discussion: Next-generation sequencing, with an appropriate multigene panel, showed great potential to assist in the diagnosis of EDS and other connective tissue disorders. Our data also show that not all causative genes giving rise to cEDS have been elucidated yet.  相似文献   
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Tan M  Jing T  Lan KH  Neal CL  Li P  Lee S  Fang D  Nagata Y  Liu J  Arlinghaus R  Hung MC  Yu D 《Molecular cell》2002,9(5):993-1004
ErbB2 overexpression confers resistance to taxol-induced apoptosis by inhibiting p34(Cdc2) activation. One mechanism is via ErbB2-mediated upregulation of p21(Cip1), which inhibits Cdc2. Here, we report that the inhibitory phosphorylation on Cdc2 tyrosine (Y)15 (Cdc2-Y15-p) is elevated in ErbB2-overexpressing breast cancer cells and primary tumors. ErbB2 binds to and colocalizes with cyclin B-Cdc2 complexes and phosphorylates Cdc2-Y15. The ErbB2 kinase domain is sufficient to directly phosphorylate Cdc2-Y15. Increased Cdc2-Y15-p in ErbB2-overexpressing cells corresponds with delayed M phase entry. Expressing a nonphosphorylatable mutant of Cdc2 renders cells more sensitive to taxol-induced apoptosis. Thus, ErbB2 membrane RTK can confer resistance to taxol-induced apoptosis by directly phosphorylating Cdc2.  相似文献   
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Feeding ecology is an important factor for the survival of a species and knowledge of its parameters is a prerequisite for successful conservation work. In this study we describe the feeding ecology of the endemic Seychelles Black Parrot Coracopsis barklyi on Praslin, Seychelles, the only island on which this parrot is resident. We compared two methods to evaluate feeding choices: incidental observations and feeding walks on 25 transects in all habitat types. Black parrots fed on 46 different species, bringing the total number of known food plants to 53 species. They predominantly consumed endemic and native species (58% of observed feeding bouts), mainly their fruit pulp (in 68% of feeding bouts), followed by buds (15%) and seeds (37%) with occasional observations of leaves, bark and scale insects. The incidental method rendered many more observed bouts than the transect approach and the ratios of consumed species differed between methods but the transect results are regarded as more representative. The incidental method is not suitable for quantitative conclusions but complements the transect method, providing information about rarely occurring feeding events.  相似文献   
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