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1.
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   
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The flat voltage noise component of current biased, high-transparency Nb/AlOx/Nb superconducting tunnel junctions has been investigated at frequencies up to 70 kHz. Several aspects of the analyzed phenomena suggest the presence of current noise effects induced by the discreteness of the charge carriers. At subgap voltages, where excess currents occur, a behavior coherent with a multiple Andreev reflection-assisted transport through the tunnel barrier has been found. However, the measured charge values exceed any theoretical prediction.  相似文献   
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Thee + e ?K + K ? cross section has been measured from about 750 events in the energy interval \(1350 \leqq \sqrt s \leqq 2400 MeV\) with the DM2 detector at DCI. TheK ± form factor |F F ±| cannot be explained by the ρ, ω, ? and ρ′(1600). An additional resonant amplitude at 1650 MeV has to be added as suggested by a previous experiment.  相似文献   
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Three-dimensional nanoporous Pt networks with a high surface area were directly grown on titanium substrates through a simple hydrothermal-assisted seed growth method.  相似文献   
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Liquid Phase Photo-Deposition (LPPD) technique has been used to obtain both colloidal particles and thin films of metallic and chloride nickel from solutions of only precursor Ni(acac)2 (acac=2,4-pentandionato). Metallic nickel was obtained from ethanol solutions by direct nickel(II) photoreduction at 254 nm and by acetone sensitised reaction at 300 nm. In this latter process the rate was higher than in the first one. NiCl2 was formed from CCl4 solution by a solvent-initiated reaction. TEM analysis, performed on colloidal particles of nickel, showed that their dimensions are in the range 2–4 nm. The films did not present carbon contamination and were characterized by AFM, XPS and GIXRD. Metallic films consisted of particles of 20–40 nm that are the result of the aggregation of smaller crystallites (4–5 nm). Larger agglomerations (around 200 nm) have been observed for NiCl2 films.  相似文献   
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The radiative decayJ/ψ → γ π+ π? has been studied using the 8.6 millionJ/ψ produced in the DM2 experiment at the DCIe +e? storage rings at Orsay. The π+ π? mass spectrum shows a cleanf 2 (1270) signal, and the possible presence of two other states at thef 2 (1720) andf 4 (2030) masses. For thef 2 (1270), the branching ratio BR(J/ψ →γf)xBR(f→π+ π?) is measured to be (7.50±0.30±1.12)×10?4, and the spin analysis prefers theJ=2 assignment, with helicity parametersx=0.83±0.06 andy=0.01±0.06. The existence of higher mass states is discussed.  相似文献   
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Titanium dioxide is extensively used in a variety of products, including industrial materials and cosmetics. Studies mainly performed on human cell lines and in vivo exposure on experimental animals have raised concern about the toxic effects of ultrafine titanium dioxide; however, scarce information is available about its impact on aquatic life. The aim of this article was to assess the genotoxic potential of TiO2 (anatase and rutile) on bottlenose dolphin leukocytes. Blood samples were obtained from four male and one female specimens reared at the Adriatic SeaWorld “Oltremare” (Riccione, Italy). Leukocytes were isolated by the lyses procedure and in vitro exposed to TiO2 in RPMI. Experimental solutions were sonicated immediately before dosing the cells. Three exposure times (4, 24 and 48 h) and three doses (20, 50 and 100 μg/ml) were tested. Genotoxicity was detected by the single-cell gel electrophoresis (or comet assay) at pH ≥ 13, assessing single/double-strand breaks and alkali-labile sites. Cytotoxicity was also detected by the Trypan blue exclusion method. Results showed that both the crystalline forms of TiO2 were genotoxic for bottlenose dolphin leukocytes, with a statistically significant increase of DNA fragmentation after exposure to 50 and 100 μg/ml for 24 and 48 h. Although preliminary, these are the first data regarding the genetic susceptibility of toothed cetaceans toward an “emerging” pollutant, such as TiO2 particles.  相似文献   
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