Search results for "wt"
showing 10 items of 5424 documents
Studies on the gastric anti-ulcer activity of hypolaetin-8-glucoside
1988
The gastric anti-ulcer activity of hypolaetin-8-O-β-D-glucoside (H-8-G), a flavonoid isolated from Sideritis leucantha, has been studied in rats. This compound significantly reduced gastric lesions induced by ethanol or acetylsalicylic acid (ASA), with an increase in mucus production. In the pylorus-ligated rat, H-8-G did not affect the volume of gastric secretion but decreased its acidity and peptic activity. The anti-ulcer activity of this flavonoid does not depend on stimulation of cell proliferation in the rat gastric mucosa. Our results suggest that H-8-G activity is related to its cytoprotective effects [mediated by endogenous prostaglandins (PGs) and associated to an increase in gast…
Seasonal variation of hypolaetin 8-glucoside inSideritis mugronensis borja
1990
A quantitative analysis of the antiinflammatory flavonoid hypolaetin 8-glucoside from Sideritis mugronensis during an annual growth cycle was carried out. After an irregular increase in spring, the maximum levels were reached and maintained in early summer samples.
Growth hormone protects human lymphocytes from irradiation-induced cell death
2003
1. Undesired effects of cancer radiotherapy mainly affect the hematopoietic system. Growth hormone (GH) participates in both hematopoiesis and modulation of the immune response. We report both r-hGH cell death prevention and restoration of secretory capacities of irradiated human peripheral blood lymphocytes (PBL) in vitro. 2. r-hGH induced cell survival and increased proliferation of irradiated cells. Western blot analysis indicated that these effects of GH were paralleled by increased expression of the antiapoptotic protein Bcl-2. 3. r-hGH restored mitogen-stimulated release of IL-2 by PBL. Preincubation of irradiated lymphocytes with the growth hormone receptor (GHR) antagonists B2036 an…
Crystal growth kinetics in deionised two-component colloidal suspensions
2007
We report first measurements of the crystal growth velocity in deionised two-component aqueous suspensions of charged polystyrene latex spheres. The size ratio was 1:1.3 and mixing ratios up to 18% of the larger particle were investigated. For the pure components limiting growth velocities of (V ∞,120 = 4.8 µm s−1 and V ∞,156 = 2.9 µm s−1) were observed. In the mixture v drops with increasing mixing ratio even below (V ∞,156) of the large minority component. Careful monitoring of the deionisation procedure excludes the explanation of enhanced ionic contamination. Alternatives based on the kinetics of particle attachment and the position of the phase boundary are discussed.
Effect of electron correlation corrections on phase competition in Ag film on MgO substrate
2002
Abstract The effect of electron correlation corrections in the novel theory predicting the growth mode of a thin metallic film on an insulating substrate has been studied. We discuss the influence of the substrate slab thickness on the energies of formation for several two-dimensional phases, which, in principle, may form in Ag layer on (0 0 1) MgO substrate. We analyze also the sensitivity of the key energy parameter––Fourier transform of the mixing potential V (0) to the choice of correlation functionals.
Negative pressures in CaWO4 nanocrystals
2009
Tetragonal scheelite-type CaWO4 nanocrystals recently prepared by a hydrothermal method show an enhancement of its structural symmetry with the decrease in nanocrystal size. The analysis of the volume dependence of the structural parameters in CaWO4 nanocrystals with the help of ab initio total-energy calculations shows that the enhancement of the symmetry in the scheelite-type nanocrystals is a consequence of the negative pressure exerted on the nanocrystals; i.e., the nanocrystals are under tension. Besides, the behavior of the structural parameters in CaWO4 nanocrystals for sizes below 10 nm suggests an onset of a scheelite-to-zircon phase transformation in good agreement with the predic…
Phase Transitions in Prequenched Mesomorphic Isotactic Polypropylene during Heating and Annealing Processes As Revealed by Simultaneous Synchrotron S…
2011
Time-resolved simultaneous synchrotron small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD) technique was used to investigate the phase transitions in prequenched mesomorphic isotactic polypropylene (iPP) samples during heating and annealing processes, respectively. For the heating process, it is shown that the mesomorphic-to-monoclinic phase transition is relatively faster for the mesomorphic iPP sample obtained with the high quenching rate than that with the low quenching rate. For the former, the stability of α-monoclinic crystals formed during heating is relatively higher. As for the annealing process, WAXD and SAXS data illustrate that the higher the annealing te…
Growing in Mafia Territories
2015
As a theoretical extension of other previous studies, this work represents an improvement of the notions about the relationship between adolescence and Mafia. The research has been aiming at exploring teenagers’ universe within specific social contexts where the presence of criminal organizations is significant, focusing the attention on the modalities through which evolutionary tasks are coped with in contexts with high Mafia density and often characterized by a perception of social space that makes personal, financial, and political development problematic. The research has involved 93 teenagers who live in southern regions where the presence of Mafia organizations (Camorra, ‘Ndrangheta, …
Differential gene expression in p53-mediated G(1) arrest of human fibroblasts after gamma-irradiation or N-phosphoacetyl-L-aspartate treatment.
2000
In human fibroblasts, N:-phosphoacetyl-L-aspartate (PALA) and gamma-radiation induce reversible and irreversible p53-mediated G(1) cell cycle arrest, respectively. By coupling the premature chromosome condensation technique to fluorescence in situ hybridization, we found no evidence of DNA damage after PALA treatment. We used representational difference analysis (cDNA-RDA) to study changes in gene expression after PALA treatment and gamma-radiation in normal human fibroblasts. The mammary-derived growth inhibitor (MDGI) gene was expressed in PALA-treated cells. Ectopic MDGI expression arrested PALA-treated but not irradiated RKO cells. Expression of an antisense RNA against MDGI resulted in…
Influence of the crystallization process on the photoelectrochemical behaviour of anodic TiO2 films
1997
On the basis of kinetic and photoelectrochemical studies we show that the formation of amorphous or strongly disordered TiO2 films on electropolished titanium rods can occur upon anodization in 0.5 M H2SO4 solution in a range of thickness which depends on the anodization rate. This finding is confirmed both by the changes in the shape of the photocurrent vs. potential curves with the energy of the incident photons, and by the impedance behaviour of the junction. Our data indicate that TiO2 films having different degree of disorder are formed depending on the anodization rate and oxide thickness. Crystalline films are formed at very low growth rates since very low thicknesses. Amorphous or s…