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311.
312.
Tumor diseases are unfortunately quick spreading, even though numerous studies are under way to improve early diagnosis and targeted treatments that take into account both the different characteristics associated with the various tumor types and the conditions of individual patients. In recent years, studies have focused on the role of ion channels in tumor development, as these proteins are involved in several cellular processes relevant to neoplastic transformation. Among all ion channels, many studies have focused on the superfamily of Transient Receptor Potential (TRP) channels, which are non-selective cation channels mediating extracellular Ca2+ influx. In this review, we examined the role of different endothelial TRP channel isoforms in tumor vessel formation, a process that is essential in tumor growth and metastasis.  相似文献   
313.
Small cell lung cancer (SCLC) is a highly aggressive malignancy that accounts for about 14% of all lung cancers. Platinum-based chemotherapy has been the only available treatment for a long time, until the introduction of immune checkpoint inhibitors (ICIs) recently changed first-line standard of care and shed light on the pivotal role of the immune system. Despite improved survival in a subset of patients, a lot of them still do not benefit from first-line chemo-immunotherapy, and several studies are investigating whether different combination strategies (with both systemic and local treatments, such as radiotherapy) may improve patient outcomes. Moreover, research of biomarkers that may be used to predict patients’ outcomes is ongoing. In addition to ICIs, immunotherapy offers other different strategies, including naked monoclonal antibodies targeting tumor associated antigens, conjugated antibody, bispecific antibodies and cellular therapies. In this review, we summarize the main evidence available about the use of immunotherapy in SCLC, the rationale behind combination strategies and the studies that are currently ongoing in this setting, in order to give the reader a clear and complete view of this rapidly expanding topic.  相似文献   
314.
We report three new mutations in PTEN, the gene responsible for Cowden disease in five patients with Bannayan-Riley-Ruvalcaba syndrome from three unrelated families. This finding confirms that Cowden disease, a dominant cancer predisposing syndrome, and Bannayan-Riley-Ruvalcaba syndrome, which includes macrocephaly, multiple lipomas, intestinal hamartomatous polyps, vascular malformations, and pigmented macules of the penis, are allelic disorders at the PTEN locus on chromosome 10q.  相似文献   
315.
J.M.D. Tascón  E.J. Bottani 《Carbon》2004,42(7):1333-1337
Monte Carlo computer simulation results on the adsorption of ethylene on C60 fullerene are employed to locate the adsorption sites observed for the adsorption of other simple gases. The distributions of molecules according to the gas-solid interaction energy obtained from the simulations are in agreement with experimental results reported in the literature. We focused our attention on the isotherm obtained at 150 K. At this temperature, the molecules with a certain gas-solid energy have been identified and their location employed to find out the adsorption sites. This sort of distribution has been averaged over all the equilibrated configurations generated during the simulation. The results obtained confirm the assignment of adsorption sites previously reported for the adsorption of N2, Ar, and CO2. The distribution of molecules over the gas-gas interaction energy is also analyzed and the obtained results suggest that the adsorbed molecules prefer a T-shaped stacking. This conclusion is obtained through the analysis of the distributions with the aid of the gas-gas interaction potential. This observation agrees with recently published results by other authors. The information obtained from the microdensity profiles has also been employed to locate the adsorption sites.  相似文献   
316.
We report the synthesis of alumina/stishovite nano‐nano composite ceramics through a pressure‐induced dissociation in Al2SiO5 at a pressure of 15.6 GPa and temperatures of 1300°C‐1900°C. Stishovite is a high‐pressure polymorph of silica and the hardest known oxide at ambient conditions. The grain size of the composites increases with synthesis temperature from ~15 to ~750 nm. The composite is harder than alumina and the hardness increases with reducing grain size down to ~80 nm following a Hall–Petch relation. The maximum hardness with grain size of 81 nm is 23 ± 1 GPa. A softening with reducing grain size was observed below this grain size down to ~15 nm, which is known as inverse Hall–Petch behavior. The grain size dependence of the hardness might be explained by a composite model with a softer grain‐boundary phase.  相似文献   
317.
A new technique using nickel–chromium wire, called the NiCr (Nichrome®) wire technique, has been presented in a first paper describing the technique [1]. This second paper focuses on the results obtained when this new technique is applied to ballistic fabrics. Strain distributions on the layer impacted, as well as in different layers, are presented. An energy balance based on the strains is shown to provide reasonable values for the elastic energy stored by the yarns. Failure times of the first layer as a function of impact velocity are discussed and a simple momentum balance is shown to predict well the deflection history of the fabric. Ultra-high-speed photography and high-speed videos allowed recording of fabric deflection vs. time. The combination of the four diagnostic techniques, including X-rays, delivers a very complete picture of the impact mechanics in fabrics, both for early-time and late-time phenomena.  相似文献   
318.
Testing and characterization of micro-electro-mechanical systems (MEMS) and micro-opto-electro-mechanical systems (MOEMS) can be very challenging due to the multi-domain nature of these devices. Nowadays high volume, high-cost, and accurate measuring systems are necessary to characterize and test MEMS and MOEMS especially to examine their motions, deflections, and resonance frequencies. This paper presents a fast-developing and low-cost environment for MEMS and MOEMS testing and characterization. The environment is based on a flexible mixed-signal platform named Intelligent Sensor InterFace (ISIF). As a case study we consider the characterization of a double axis scanning micromirror. The testing environment has been validated by comparing measurement results with results obtained by the finite element method simulations performed with Comsol Multiphysics. Finally, these results have been exploited to create an electrical equivalent model of the micromirror.  相似文献   
319.
The focus of the present research was to study inhibition of lipoxygenase activity by rapeseed native polyphenols and the interactions between those compounds and the enzyme. The enzyme and polyphenolic compounds (polyphenols, phenolic acids) were extracted from rapeseed (Brassica napus) varieties Aviso and PR45DO3. The total phenolic compounds concentration in tested rapeseed was 1,485–1,691 mg/100 g d.m. (dry matter) and the free phenolic acids content in both rapeseed varieties was about 76 μg/100 g d.m. The isolated proteins showed lipoxygenase activity. Prooxidant properties of phenolic compounds in the presence of lipoxygenase and linoleic acid were observed rather in the case of extracts containing a relatively high concentration of miscellaneous polyphenols. Antioxidant properties were recorded in the case of phenolic acid extracts which contain only 1.4–1.9% of phenolics present in raw phenolic extracts. We propose that the prooxidant effect of phenolic compounds comes from quinone and oxidized polyphenols formation. The observed antioxidant activity of phenolic acid extracts is probably due to their ability to scavenge free radicals formed from linoleic acid. However, reduction of lipoxygenase ferric to ferrous ions, which prevent the activation of the enzyme and inhibited its activity, was also observed.  相似文献   
320.
Magnetic susceptibility, EPR and optical properties have been studied in a glass system {20La2O3−22Al2O3−23 B2O3−35(SiO2+GeO2)} with a part of La2O3 substituted by Gd2O3 in different concentrations. Positive Weiss constants have been found in more heavily doped glasses; two magnetic transitions at 55 and 12 K have been detected and ascribed, respectively, to ferromagnetic and antiferromagnetic clusters of Gd3+ ions. The EPR spectra confirm the clustering at higher Gd contents. At low temperatures the cluster-related resonance indicates an onset of magnetic anisotropy. The clustering, depending on the Gd concentration, correlates with a shift to lower energies of the strong optical absorption band edge.  相似文献   
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