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991.
Paola Goldoni Lorena Cattani Stefania Carrara Maddalena Castellani Pastoris Laura Sinibaldi Nicola Orsi 《Microbiology and immunology》1998,42(4):271-279
A study has been carried out on the action of cytoskeleton and metabolic inhibitors on intracellular multiplication in HeLa cells of a virulent strain of Legionella pneumophila serogroup 6. The effects of the substances were separately tested on both penetration and intracellular multiplication of L. pneumophila. Only cytochalasin A and 2-deoxy-d -glucose (2dG) affected bacterial internalisation, whereas intracellular multiplication was inhibited by cytochalasins A, B, C, D and J (D being the most active) and by 2dG with a dose-response effect. The action of 2dG was counteracted by 50 mM glucose. Experiments carried out with cytochalasin D and a rhodamine-phalloidin conjugate showed the involvement of cytoskeletal elements in intracellular multiplication of Legionella; compounds acting on microtubules had no effect. 相似文献
992.
Adriana Bochicchio Concetta Vazzana Serenella Puliga Alessandra Alberti Stefania Cinganelli Paolo Vernieri 《Plant Growth Regulation》1998,24(3):163-170
In our experimental conditions detached leaves of the resurrection plant Boea hygroscopica survived equilibration to 65–80% RH (Relative Humidity), but not to very low RH (close to 0%). The first aim of our research was to determine whether sensitivity to equilibration to very low RH depends on the rate of the drying process or on the very low final MC (Moisture Content) attained. The second aim of our research was to determine ABA content of leaves exposed to the two drying processes: a first step towards understanding whether ABA is involved in the tolerance mechanism of Boea hygroscopica.Detached leaves were equilibrated either to 1.4 or to 60–70% RH or to various temporal combinations of these two RH. ABA content was monitored during drying. Dehydrated leaves were imbibed in liquid water either directly or after a slow rehydration at 98% RH. Tolerance was assessed after 48 h imbibition in liquid water.The low final MC attained (about 3%) and not the rate of drying was responsible of the sensitivity of leaves equilibrated to 1.4% RH. Slow rehydration attained better recovery, but it was not able to allow full resurrection thus suggesting that a plain biophysical liquid-crystalline to gel phase transition of the membrane lipid bilayer could not fully account for the lethal damage of the very low MC.The conclusions relative to the first part of our research was of primary importance in interpreting results concerning ABA variations during the two drying treatments. ABA showed a very similar transient increase when excised leaves were dried at either 1.4% RH (sensitive leaves) or at 60–70% RH (tolerant leaves). However we cannot exclude that the transient increase of the hormone is a necessary component of the desiccation tolerance mechanisms in detached leaves of Boea hygroscopica: the extremely low MC reached by equilibration to 1.4% RH may impair the mechanism itself. 相似文献
993.
Modifications in the exposure to the solvent of hydrophobic residues, changes in their organization into surface hydrophobic patches, and alterations in the dimerization equilibrium of-lactoglobulin upon thermal treatment at neutralpH were studied. Exposure of tryptophan residues was temperature dependent and was essentially completed on the time scale of seconds. Reorganization of generic hydrophobic protein patches on the protein surface was monitored through binding of 1,8-anilinonaphthalenesulfonate, and was much slower than changes in tryptophan exposure. Different phases in surface hydrophobicity changes were related to the swelling and the subsequent collapse of the protein, which formed a metastable swollen intermediate. Heat treatment of-lactoglobulin also resulted in the formation of soluble oligomeric aggregates. The aggregation process was studied as a function of temperature, demonstrating that (i) dimer dissociation was a necessary step in a sequential polymerization mechanism and (ii) cohesion of hydrophobic patches was the major driving force for aggregation. 相似文献
994.
Stefania Agostini Cristina Bolzati Eliana Didonè Mario Cavazza-Ceccato Fiorenzo Refosco Luigi Aloj Claudio Arra Michela Aurilio Anna Lucia Tornesello Diego Tesauro Giancarlo Morelli 《Journal of peptide science》2007,13(4):211-219
The radiolabeling of the natural octapeptide CCK8, derivatized with a cysteine residue (Cys-Gly-CCK8), by using the metal fragment [99mTc(N)(PNP3)]2+ (PNP3 = N,N-bis(dimethoxypropylphosphinoethyl)methoxyethylamine) is reported. The [99mTc(N)(NS-Cys-Gly-CCK8)(PNP3)]+ complex was obtained according to two methods (one-step or two-step procedure) that gave the desired compound in high yield. The complex is stable in aqueous solution and in phosphate buffer. In vitro challenge experiments with an excess of cysteine and glutathione indicate that no transchelation reactions occur, confirming the high thermodynamic stability and kinetic inertness of this compound. Stability studies carried out in human and mouse serum, as well as in mouse liver homogenates, show that the radiolabeled compound remains intact for prolonged incubation at 37 degrees C. Binding properties give Kd (19.0 +/- 4.6 nmol/l) and Bmax (approximately 10(6) sites/cell) values in A431 cells overexpressing the CCK2-R. In vivo evaluation of the compound shows rapid and specific targeting to CCK2-R, a fourfold higher accumulation compared to nonreceptor expressing tumors. 相似文献
995.
996.
6‐Mer Hyaluronan Oligosaccharides Modulate Neuroinflammation and α‐Synuclein Expression in Neuron‐Like SH‐SY5Y Cells
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![点击此处可从《Journal of cellular biochemistry》网站下载免费的PDF全文](/ch/ext_images/free.gif)
997.
Marco Romano Simone Maganuco Stefania Nosotti Fabio Manucci 《Historical Biology》2016,28(8):1014-1025
Since their initial formal recognition by Richard Owen in 1842, dinosaurs have always stood out in the collective imagination for their size and unusual appearance. Therefore, these marvellous animals are a source of curiosity and wonder for people of all ages, social and cultural backgrounds. Thanks to improved research techniques, palaeontologists have been able to work reconstructing the most plausible appearance of dinosaurs. Starting with petrified bones, they tried to make a dream come true – to bring the planet’s ancient inhabitants back to life. The new Italian exhibition Dinosaurs in the Flesh: Science and Art bring the Rulers of a Lost World Back to Life reveals the marriage of science and art that brings back to life animals that lived tens or hundreds of millions of years ago. Palaeontologists and artists collaborate on reconstructing the appearance of organisms from the distant past through study of the fossils, often with the aid of new technologies. The new project, which takes up the idea of Waterhouse Hawkins and Owen and their legacy to restore these ancient vertebrates based on solid scientific foundations, represents to date the only way to reanimate these fascinating lost animals. 相似文献
998.
G‐CSF contributes at the healing of tunica media of arteriotomy‐injured rat carotids by promoting differentiation of vascular smooth muscle cells
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![点击此处可从《Journal of cellular physiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
999.