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131.
132.
Fr. Keil 《Plant Systematics and Evolution》1851,1(33):266-268
Ohne Zusammenfassung 相似文献
133.
In Parkinson''s disease, the long-term use of dopamine replacing agents is associated with the development of motor complications; therefore, there is a need for non-dopaminergic drugs. This study evaluated the potential therapeutic impact of six different NR2B and A2A receptor antagonists given either alone or in combination in unilateral 6-OHDA-lesioned rats without (monotherapy) or with (add-on therapy) the co-administration of L-Dopa: Sch-58261+ Merck 22; Sch-58261+Co-101244; Preladenant + Merck 22; Preladenant + Radiprodil; Tozadenant + Radiprodil; Istradefylline + Co-101244. Animals given monotherapy were assessed on distance traveled and rearing, whereas those given add-on therapy were assessed on contralateral rotations. Three-way mixed ANOVA were conducted to assess the main effect of each drug separately and to determine whether any interaction between two drugs was additive or synergistic. Additional post hoc analyses were conducted to compare the effect of the combination with the effect of the drugs alone. Motor activity improved significantly and was sustained for longer when the drugs were given in combination than when administered separately at the same dose. Similarly, when tested as add-on treatment to L-Dopa, the combinations resulted in higher levels of contralateral rotation in comparison to the single drugs. Of special interest, the activity observed with some combinations could not be described by a simplistic additive effect and involved more subtle synergistic pharmacological interactions. The combined administration of A2A/NR2B-receptor antagonists improved motor behaviour in 6-OHDA rats. Given the proven translatability of this model such a combination may be expected to be effective in improving motor symptoms in patients. 相似文献
134.
135.
Tomasz Frączyk 《化学与生物多样性》2021,18(4):e2100043
Proteins anchor copper(II) ions mainly by imidazole from histidine residues located in different positions in the primary protein structures. However, the motifs with histidine in the first three N-terminal positions (His1, His2, and His3) show unique Cu(II)-binding properties, such as availability from the surface of the protein, high flexibility, and high Cu(II) exchangeability with other ligands. It makes such sequences beneficial for the fast exchange of Cu(II) between ligands. Furthermore, sequences with His1 and His2, thus, non-saturating the Cu(II) coordination sphere, are redox-active and may play a role in Cu(II) reduction to Cu(I). All human protein sequences deposited in UniProt Knowledgebase were browsed for those containing His1, His2, or His3. Proteolytically modified sequences (with the removal of a propeptide or Met residue) were taken for the analysis. Finally, the sequences were sorted out according to the subcellular localization of the proteins to match the respective sequences with the probability of interaction with divalent copper. 相似文献
136.
B Balogh M Wessig P Waldh?usl W Millesi H Millesi W Firbas F Frühwald 《Acta anatomica》1988,133(3):183-187
The present study has attempted to determine the volume, square measure as well as length, width and thickness of the individual muscles of facial expression by photogrammetry. 15 fresh male head specimens were employed for a careful dissection of muscle layers. The volume was measured using the immersion procedure. The mean values of each parameter together with the standard deviation were summarized. The results suggest that this novelty in the representation of the mimetic muscles will facilitate the planning of corrective interventions in plastic surgery. Moreover, photogrammetry offers additional information on the required size and measurements of donor muscles. 相似文献
137.
The efficiency of ethyleneglycol-bis (β-amino-ethyl ether) N,N′-tetra-acetic acid (EGTA) in removing possible contamination from myelin was tested. Myelin fractions were isolated in the presence or absence of EGTA. An axolemma-enriched fraction was also prepared. Gel electrophoresis showed no important alteration of the protein pattern of myelin treated with EGTA. Only a minor band of about 41,000 daltons was selectively removed when EGTA was used during the two density gradient and differential centrifugation steps. EGTA, when used in the final washes, did not remove this band. It was absent from axolemma-enriched fractions. Different hypotheses are considered to explain these findings. 相似文献
138.
Jean-Marie Matthieu John L. Everly Roscoe O. Brady Richard H. Quarles 《Biochimica et Biophysica Acta (BBA)/General Subjects》1975,392(1):167-174
The in vivo incorporation of [3 5S]sulfate, [3H]fucose and [3H]leucine into sciatic nerve myelin was investigated. Polyacrylamide gel electrophoresis of the proteins indicated that the 3 5S-labeling of proteins occurred almost exclusively in the major myelin protein. A smaller myelin glycoprotein migrating just ahead of the major one was labeled with [3H]fucose but did not incorporate 3 5S to a detectable extent. There was little or no 3 5S associated with basic proteins on polyacrylamide gels when the proteins were extracted with chloroform/methanol. Fucose-labeled myelin glycoproteins were converted to glycopeptides by pronase digestion. The glycopeptides gave a single peak on Sephadex G-50 in which the 3H and 3 5S coincided. The association of 3 5S with glycopeptides was not caused by binding of sulfatide or free inorganic sulfate. This study shows that the major myelin protein in the sciatic nerve of the rat is glycosylated and sulfated. 相似文献
139.
Nirvana Sadaghianloo Julie Contenti Maeva Dufies Julien Parola Matthieu Rouleau Shinrong Lee Jean-François Peyron Lucilla Fabbri Réda Hassen-Khodja Jacques Pouysségur Frédéric Bost Elixène Jean-Baptiste Alan Dardik Nathalie M. Mazure 《Journal of cellular and molecular medicine》2020,24(5):2931-2941
Arteriovenous fistulas (AVFs) are the preferred vascular access for haemodialysis of patients suffering from end-stage renal disease, a worldwide public health problem. However, they are prone to a high rate of failure due to neointimal hyperplasia and stenosis. This study aimed to determine if osteopontin (OPN) was induced in hypoxia and if OPN could be responsible for driving AVF failure. Identification of new factors that participate in remodelling of AVFs is a challenge. Three cell lines representing the cells of the three layers of the walls of arteries and veins, fibroblasts, smooth muscle cells and endothelial cells, were tested in mono- and co-culture in vitro for OPN expression and secretion in normoxia compared to hypoxia after silencing the hypoxia-inducible factors (HIF-1α, HIF-2α and HIF-1/2α) with siRNA or after treatment with an inhibitor of NF-kB. None of the cells in mono-culture showed OPN induction in hypoxia, whereas cells in co-culture secreted OPN in hypoxia. The changes in oxygenation that occur during AVF maturation up-regulate secretion of OPN through cell-cell interactions between the different cell layers that form AVF, and in turn, these promote endothelial cell proliferation and could participate in neointimal hyperplasia. 相似文献
140.
Fournier Thomas Fèvre Jordan Carcaillet Frédérique Carcaillet Christopher 《Plant Ecology》2020,221(7):559-576
Plant Ecology - Changes in community diversity and dynamics after fires in Mediterranean ecosystems are rarely investigated more than a few years after the fire even though pronounced changes can... 相似文献