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排序方式: 共有146条查询结果,搜索用时 46 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.
In this paper we show the existence of a solution, on any time intervals, in suitable Sobolev spaces for the 2D compressible
Euler equation in the exterior domain, when the Mach number is sufficiently small. We shall extend results obtained in [8]
in the case of an infinity velocity different from zero.
Sunto In questo lavoro proviamo l'esistenza di una soluzione, su ogni intervallo temporale, in opportuni spazi di Sobolev per le equazioni di Eulero 2D comprimibili in un dominio esterno, quando il numero di Mach è sufficientemente piccolo. Estenderemo i risultati ottenuti in [8] al caso di velocità all'infinito diversa da zero.相似文献
3.
4.
R. A. Dewberry S. R. Salaymeh V. R. Casella F. S. Moore 《Journal of Radioanalytical and Nuclear Chemistry》2006,267(3):515-531
Summary This paper contains a summary of the holdup and material control and accountability (MC&A) assays conducted for the determination
of highly enriched uranium (HEU) in the deactivation and decommissioning (D&D) of the Reactor Fuel Fabrication Facility at
the Savannah River Site (SRS). The facility was used to fabricate HEU fuel assemblies, lithium-aluminum target tubes, neptunium
assemblies, and miscellaneous components for the SRS production reactors. The facility operated for more than 35 years. During
this time thousands of uranium-aluminum alloy (U-Al) production reactor fuel tubes were produced. After the facility ceased
operations in 1995, all of the easily accessible U-Al was removed from the building, and only residual amounts remained. The
bulk of this residue was located in the equipment that generated and handled small U-Al particles and in the exhaust systems
for this equipment (e.g., chip compactor, casting furnaces, log saw, lathes A & B, cyclone separator, Freon?cart, riser crusher,
…, etc). The D&D project is likely to represent an important example for D&D activities across SRS and across the Department
of Energy weapons complex. The Savannah River National Laboratory was tasked to conduct holdup assays to quantify the amount
of HEU on all components removed from the facility prior to placing in solid waste containers. The 235U holdup in any single component of process equipment must not exceed 50 g in order to meet the container limit. This limit
was imposed to meet criticality requirements of the low level solid waste storage vaults. Thus, the holdup measurements were
used as guidance to determine if further decontamination of equipment was needed to ensure that the quantity of 235U did not exceed the 50 g limit and to ensure that the waste met the Waste Acceptance Criteria (WAC) of the solid waste storage
vaults. Since HEU is an accountable nuclear material, the holdupassays and assays of recovered residue were also important
for material control and accountability purposes. In summary, the results of the holdup assays were essential for determining
compliance with the Waste Acceptance Criteria, Material Control & Accountability, and to ensure that administrative criticality
safety controls were not exceeded. This paper discusses theg-ray assay measurements conducted and the modeling of the acquired
data to obtain measured holdup in process equipment, exhaust components, and fixed geometry scrap cans. It also presents development
work required to model new acquisition configurations and to adapt available instrumentation to perform the assays. 相似文献
5.
Emiliano Bedini Antonella Carabellese Marialuisa Schiattarella Michelangelo Parrilli 《Tetrahedron》2005,61(23):5439-5448
3-Acetamido-3,6-dideoxy-d-galactopyranose (d-Fucp3NAc) is an aminosugar almost exclusively found in phytopathogenic O-antigens. The glycosylation reaction involving d-Fucp3NAc donors was studied with several rhamnosyl acceptors, revealing that the best yields and highest α-stereoselectivity were obtainable by coupling a N-phenyl trifluoroacetimidate glycosyl donor in a ternary mixture (dioxane/DME/toluene 4:1:1) as solvent. For the first time a synthetic access to α-d-Fucp3NAc containing oligorhamnans, that are interesting molecules for studying the effects of O-antigen model oligosaccharides on the modulation of plant response to bacteria, was reported. An example is the pentasaccharide repeating unit of the major O-antigen component from Pseudomonas syringae pv. holci IMV 8300, which was synthesized as its methyl glycoside. 相似文献
6.
Dieter Jungnickel Marialuisa J. de Resmini Scott A. Vanstone 《Designs, Codes and Cryptography》1996,8(1-2):159-165
We consider the problem of embedding the even graphical code based on the complete graph onn vertices into a shortening of a Hamming code of length 2m-1, wherem = h(n) should be as small as possible. As it turns out, this problem is equivalent to the existence problem for optimal codes with minimum distance 5, and optimal embeddings can always be realized as graphical codes based onK
n. As a consequence, we are able to determineh(n) exactly for alln of the form 2
k
+ 1 and to narrow down the possibilities in general to two or three conceivable values.Dedicated to Hanfried Lenz on the occasion of his 80th birthdayThe research for this note was done while the first author was visiting the University of Waterloo and the University of Rome, respectively. He thanks his colleagues there for their hospitality and also acknowledges the financial support of the Consiglio Nazionale delle Ricerche (Italy). The third author acknowledges the support of the National Science and Engineering Research Council of Canada given under grant #0GP0009258. 相似文献
7.
Marialuisa Russo Gabriella Poggi Maria Luisa Navacchia Mila D'Angelantonio Salvatore S Emmi 《Research on Chemical Intermediates》2006,32(2):153-170
Chemical radiolytic oxidation induced by OH addition on 1-(2-furan-2-yl-5-hydroxy-6-hydroxymethyl-[1,3]dioxan-4-yl)-ethan-1,2-diol
(sorbitylfurfural, SF) leads, in the presence of controlled amounts of oxygen, to a permanent functional modification of the
target molecule. The yield of conversion reaches 60% of the starting material. LC-MS analysis allowed the identification,
as final products, of carboxylic acids, butenal and hydroxy-furan derivatives in which the sugar chain remains unbroken, while
the furanic ring is attacked first by OH and then by oxygen, giving in succession an intra-/inter-molecular rearrangement
of the allylperoxyl radicals thus formed. The proposed oxidation of the furanic ring envisages the peroxyl intermediates undergoing
mono- and/or bi-molecular reactions; a reaction path has been outlined and is reported here. The presence of unsaturated bonds
in the final products could provide a further site for radical scavenger activity. Therefore, the fast reaction with O2 and the rearrangement of the produced peroxyl radicals to species, which are likely to be effective OH-capturers, reinforces
the antioxidant ability of SF. 相似文献
8.
A nickel-catalysed chemically modified electrode is described which seems to represent a convenient compromise between ease of preparation, reproducibility, precision and detection limits for the determination of carbohydrates in biological matrices. 相似文献
9.
Casella L Monzani E Fantucci P Gullotti M De Gioia L Strini A Chillemi F 《Inorganic chemistry》1996,35(2):439-444
The effect of strain in the axial coordination of imidazole to the heme has been studied in the chelate complexes deuterohemin-histidine (DH-His) and deuterohemin-alanylhistidine (DH-AlaHis). Molecular mechanics calculations indicate that three types of distortion of the axial ligand occur in DH-His, due to the relatively short length of the arm carrying the donor group: tilting off-axis, tipping, and inclination of the imidazole plane with respect to the axial Fe-N bond. The effects of tilting (Deltagamma approximately 10 degrees ) and inclination of the imidazole ring (Deltadelta approximately 17 degrees ) are dominant, while tipping is small and is probably of little importance here. By contrast, the axial imidazole coordination is normal in DH-AlaHis and other computed deuterohemin-dipeptide or -tripeptide complexes where histidine is the terminal residue, the only exception being DH-ProHis, where the rigidity of the proline ring reduces the flexibility of the chelating arm. The distortion in the axial iron-imidazole bond in DH-His has profound and negative influence on the binding and catalytic properties of this complex compared to DH-AlaHis. The former complex binds more weakly carbon monoxide, in its reduced form, and imidazole, in its oxidized form, than the latter. The catalytic efficiency in peroxidative oxidations is also reduced in DH-His with respect to DH-AlaHis. The activity of the latter complex is similar to that of microperoxidase-11, the peptide fragment incorporating the heme that results from hydrolytic cleavage of cytochrome c. 相似文献
10.
A cobalt oxyhydroxide film dispersed on a carbon electrode surface was characterized and proposed as an amperometric sensor for determination of alditols and carbohydrates in flowing streams. Complex mixtures of carbohydrates were separated by anion-exchange chromatography using a moderately alkaline solution as mobile phase. The cobalt modified electrode (GC-Co) was employed under a constant applied potential of 0.5 V (vs Ag/AgCl). Under these experimental conditions the detection limits (S/N=3) for all analyzed electroactive molecules ranged between 0.3 micromol L(-1) and 1.5 micromol L(-1) and the dynamic linear ranges spanned generally three orders of magnitude above the relevant detection limits. Analytical determinations of carbohydrates and alditols in red and white wines, are reported. 相似文献