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排序方式: 共有423条查询结果,搜索用时 15 毫秒
1.
Ersilia Nigro Marialuisa Formato Giuseppina Crescente Aurora Daniele 《Molecules (Basel, Switzerland)》2021,26(9)
Cannabis sativa L. is a source of over 150 active compounds known as phytocannabinoids that are receiving renewed interest due to their diverse pharmacologic activities. Indeed, phytocannabinoids mimic the endogenous bioactive endocannabinoids effects through activation of CB1 and CB2 receptors widely described in the central nervous system and peripheral tissues. All phytocannabinoids have been studied for their protective actions towards different biological mechanisms, including inflammation, immune response, oxidative stress that, altogether, result in an inhibitory activity against the carcinogenesis. The role of the endocannabinoid system is not yet completely clear in cancer, but several studies indicate that cannabinoid receptors and endogenous ligands are overexpressed in different tumor tissues. Recently, in vitro and in vivo evidence support the effectiveness of phytocannabinoids against various cancer types, in terms of proliferation, metastasis, and angiogenesis, actions partially due to their ability to regulate signaling pathways critical for cell growth and survival. The aim of this review was to report the current knowledge about the action of phytocannabinoids from Cannabis sativa L. against cancer initiation and progression with a specific regard to brain, breast, colorectal, and lung cancer as well as their possible use in the therapies. We will also report the known molecular mechanisms responsible for such positive effects. Finally, we will describe the actual therapeutic options for Cannabis sativa L. and the ongoing clinical trials. 相似文献
2.
Giuseppina Vannella 《Annali di Matematica Pura ed Applicata》2002,180(4):429-440
We consider a Neumann problem of the type -εΔu+F
′(u(x))=0 in an open bounded subset Ω of R
n
, where F is a real function which has exactly k maximum points.
Using Morse theory we find that, for ε suitably small, there are at least 2k nontrivial solutions of the problem and we give some qualitative information about them.
Received: October 30, 1999 Published online: December 19, 2001 相似文献
3.
Giuseppina Castronuovo Vittorio Elia Filomena Velleca 《Journal of solution chemistry》1995,24(12):1209-1217
Calorimetric measurements were carried out at 25°C on binary and ternary aqueous solutions containing L and D forms fo the following -aminoacids: tryptophan, cysteine, methionine, phenylalanine, histidine, threonine, and citrulline, which contain both hydrophilic and hydrophobic domains. Differences were found between the values of the homochiral and heterochiral pairwise enthalpic interaction coefficients for tryptophan, cysteine, and methionine. To the contrary, chiral recognition was not detected for phenylalanine, histidine, citrulline, and threonine. The data were interpreted in terms of a preferential configuration model. Chiral recognition is detected only when the interactions of the side chains in the homo- and heterochiral configurations are different. Chiral recognition disappears when a competition exists between zwitterion-zwitterion interactions and side chain-side chain interactions. In some cases, such as for citrulline, compensation effects can occur due to thermal contributions from different domains which mask chiral recognition. 相似文献
4.
María?Belén?Sierra Marcela?A.?Morini Pablo?C.?SchulzEmail author María?Luján?Ferreira 《Colloid and polymer science》2005,283(9):1016-1024
Following the studies on the effect of double bonds in the surfactant hydrophobic tail on the formation of mixed surfactant aggregates, we studied the viscosity and density of the system Sodium 10-undecenoate (SUD)–decyltrimethylammonium bromide (DTAB)–water. We found that the partial molar volume (pmv) and intrinsic viscosity of both, micellised and unmicellised mixtures, are non-ideal, dependent on the mixture composition and related to structural changes in micelles. These phenomena are caused by the presence of the double bond at the distal extreme of the SUD molecule, which has some affinity with water by formation of hydrogen bonds. In particular, as far as we know, this is the first report on non-ideal behavior of the pmv in mixed micelles. 相似文献
5.
The aqueous cationic system sodium undecenoate-dodecyltrimethylammonium bromide at low concentration
Maria?Belén?Sierra Marcela?A.?Morini Pablo?C.?SchulzEmail author 《Colloid and polymer science》2004,282(6):633-641
The aqueous sodium undecenoate (SUD) –dodecyltrimethylammonium bromide (DTAB) catanionic system was studied at low concentration. The system did not precipitate, even at a 1:1 SUD:DTAB proportion, but showed the formation of a coacervate in a range of surfactant mixture compositions. Micelles have a preferential composition of 0.37 mole fraction of SUD. This behavior is attributed to the presence of the double bond at the distal extreme of the SUD molecule, which can form hydrogen bonds with water. Consequently, the –CH=CH2 group is situated at the interface between the hydrocarbon micelle core and water, reducing the interfacial free energy. Structural computations demonstrate that the mentioned SUD proportion produces complete coverage of the micelle surface by the double bonds. 相似文献
6.
Celebre G De Luca G Longeri M Pileio G Emsley JW 《The Journal of chemical physics》2004,120(15):7075-7084
The proton NMR spectra of two (13)C-labeled isotopomers of styrene dissolved in two liquid crystalline solvents have been obtained and analyzed to yield four sets each of 24 dipolar couplings. These couplings were then used to investigate the structure of the ring and the ene fragments of the molecule, and the position of the maximum, phi(0), in the ring-ene bond rotational probability distribution. To do this, the effect on the dipolar couplings of small-amplitude vibrational motion was taken into account using vibrational wave functions calculated by molecular orbital and density functional methods. It is concluded that the NMR data are consistent with the ring fragment, averaged over the ring-ene rotation, planar, while the ene fragment is not. The value of phi(0) is found to be 18.0 degrees +/-0.2 degrees for the two solutions, compared with a value of 27 degrees calculated by the molecular method MP2/6-31G(*). 相似文献
7.
Cerruti M Perardi A Cerrato G Morterra C 《Langmuir : the ACS journal of surfaces and colloids》2005,21(20):9327-9333
Morphological and structural variations of particles of Bioglass with two different grain sizes reacted in Tris-buffered solution were analyzed by means of N(2) adsorption/desorption at 77 K and HR-TEM/EDS. A remarkable increase in specific surface area (ssa) was observed after the first hour of dissolution. A plateau value corresponding to an increase of at least 2 orders of magnitude was reached after 2 days of dissolution. The ssa increase was faster for the smaller particle size sample, and the ratio between the ssa of the starting samples was not maintained during dissolution. Both micro- and mesopores were formed at different stages of the reaction for the two samples. Increasing ssa was also connected to the formation of a microcrystalline structure rich in Ca and P, as shown by TEM images. The segregation of both a SiO(2)-rich amorphous phase and a Ca/P-rich crystalline phase was observed after the first hour of dissolution. After 2 days of reaction, Ca/P-rich particles made of fine aciculate crystals were found either in close contact with SiO(2) particles or deposited on a small SiO(2)-rich core. A preliminary analysis of TEM data showed the formation, together with hydroxy carbonate apatite, of different types of calcium phosphates not detectable by powder X-ray diffraction. 相似文献
8.
Paula?Messina Marcela?A.?Morini Pablo?C.?SchulzEmail author 《Colloid and polymer science》2003,281(7):695-698
The hydration of micellised sodium dehydrocholate molecules was determined by viscosity measurements. It was found that there are 39 water molecules for each micellised surfactant molecule. About ten water molecules may be attributed to the hydration of the sodium carboxylate group. By assignation of two water molecules to each of the three carbonyl groups, the total hydration of a micellised sodium dehydrocholate molecule was estimated as about 16 water molecules. The remaining 23 water molecules per micellised sodium dehydrocholate molecule may be attributed to water trapped in the structure of micelles. 相似文献
9.
10.
Guido Barone Giuseppina Castronuovo Vittorio Crescenzi Vittorio Elia Eugenio Rizzo 《Journal of solution chemistry》1978,7(3):179-192
In order to clarify some aspects of the hydrophobic interactions, the enthalpies of dilution of monoethylurea, 1,3-dimethylurea,
and 1,3-diethylurea have been determined calorimetrically at 25°C. The calorimetric data, expressed in terms of excess enthalpy,
permit the evaluation of the pair and triplet interaction coefficients. The analyses of these and of the analogous coefficientsg
xx andg
xxx, derived from osmotic data, indicate a driving force favorable to the interactions among the hydrated solute molecules. Nevertheless,
the positive values of theh
xx andh
xxx coefficients seem to suggest that the source of the effect is a rearrangement of the water molecules rather than a direct
association of the solute molecules. There are evidences of a strict correlation between the enthalpic and the entropic effects.
Preliminary data were presented at the International Conferences on Chemical Thermodynamics at Baden (1973) and Montpellier
(1975). The experimental part was carried out at the Istituto Chimico of the University of Trieste.
To whom correspondence should be addressed. 相似文献