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451.
Kostadinova E Nikolova D Alipieva K Stefova M Stefkov G Evstatieva L Matevski V Bankova V 《Natural product research》2007,21(9):819-823
The essential oils of two species of Sideritis growing spontaneously in Bulgaria and Macedonia are reported, Sideritis scardica and Sideritis raeseri. The oils of S. scardica from different locations differed significantly: in the Macedonian sample alpha-cadinol (20%) predominated, while in the oil of Bulgarian samples the main components were diterpenic compounds and octadecenol (over 20%). This is the first report of ditrpenoids in essential oil of S. scardica. The oil of S. raeseri demonstrated a distinct chemical profile with its high concentration of sesquiterpenes, main components being germacrone (25%) and elemol acetate (15.9%). The observed qualitative variability of the oil composition of S. scardica of different geographic origin could be a result of different ecologic conditions but might also reflect the well-known tendency of some Sideritis species to hybridize. 相似文献
452.
Natasha Irrera Alessandra Bitto Emanuela SantAntonio Rita Lauro Caterina Musolino Alessandro Allegra 《Molecules (Basel, Switzerland)》2021,26(13)
The endocannabinoid system (ECS) is a composite cell-signaling system that allows endogenous cannabinoid ligands to control cell functions through the interaction with cannabinoid receptors. Modifications of the ECS might contribute to the pathogenesis of different diseases, including cancers. However, the use of these compounds as antitumor agents remains debatable. Pre-clinical experimental studies have shown that cannabinoids (CBs) might be effective for the treatment of hematological malignancies, such as leukemia and lymphoma. Specifically, CBs may activate programmed cell death mechanisms, thus blocking cancer cell growth, and may modulate both autophagy and angiogenesis. Therefore, CBs may have significant anti-tumor effects in hematologic diseases and may synergistically act with chemotherapeutic agents, possibly also reducing chemoresistance. Moreover, targeting ECS might be considered as a novel approach for the management of graft versus host disease, thus reducing some symptoms such as anorexia, cachexia, fatigue, anxiety, depression, and neuropathic pain. The aim of the present review is to collect the state of the art of CBs effects on hematological tumors, thus focusing on the essential topics that might be useful before moving into the clinical practice. 相似文献
453.
Martin Rosenthal David Doblas Jaime J. Hernandez Yaroslav I. Odarchenko Manfred Burghammer Emanuela Di Cola Denis Spitzer A. E. Antipov L. S. Aldoshin Dimitri A. Ivanov 《Journal of synchrotron radiation》2014,21(1):223-228
A microelectromechanical‐systems‐based calorimeter designed for use on a synchrotron nano‐focused X‐ray beamline is described. This instrument allows quantitative DC and AC calorimetric measurements over a broad range of heating/cooling rates (≤100000 K s?1) and temperature modulation frequencies (≤1 kHz). The calorimeter was used for high‐resolution thermal imaging of nanogram‐sized samples subjected to X‐ray‐induced heating. For a 46 ng indium particle, the measured temperature rise reaches ~0.2 K, and is directly correlated to the X‐ray absorption. Thermal imaging can be useful for studies of heterogeneous materials exhibiting physical and/or chemical transformations. Moreover, the technique can be extended to three‐dimensional thermal nanotomography. 相似文献
454.
Wanda Ziemkowska Dariusz Basiak Patrycja Kurtycz Agnieszka Jastrzębska Andrzej Olszyna Antoni Kunicki 《Chemical Papers》2014,68(7):959-968
Nano-titania doped with noble metals (Au/TiO2, Ag/TiO2, Pd/TiO2) has been synthesized by mild hydrolysis of the mixture of metal salts or complexes and titanium isopropoxide ((iPr-O)4Ti). After thermal decomposition of the obtained precursors, nanomaterials were formed. Morphological characterization of the nanomaterials was provided by scanning electron microscopy (SEM) and stereological analysis, determining the BET specific surface area, and BJH nanoporosity (pore volume, pore size). It has been found that the structure of nanomaterials (size of nanoparticles and agglomerates) depended strongly on the method of the (iPr-O)4Ti hydrolysis. A minor dependence on the kind of solvents and precursors of noble metals was observed. The presence of doping metal nanoparticles was confirmed by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX). Nanomaterial phases were identified by X-ray diffraction (XRD). According to the XRD patterns, Ag/TiO2 and Pd/TiO2 products with doping metals in their oxidized form contain Ag-Ti and Pd-Ti phases. Peaks of the metal oxides Ag2O and PdO are absent in the XRD patterns. The average size of TiO2 nanoparticles is situated in the region of 20–60 nm, whereas metals are present as about 10–15 nm sized particles and fine nanoparticles. 相似文献
455.
Komsta Łukasz Smardz Patrycja Pietraś Rafał Skibiński Robert Gumieniczek Anna 《平面色谱法杂志一现代薄层色谱法》2014,27(3):229-232
JPC – Journal of Planar Chromatography – Modern TLC - The retention (RM) values of nine one-point adsorption model compounds: diphenylamine, indol, 2-naphtol, 1-naphtol, 1-naphtylamine,... 相似文献
456.
Maura Pellei Simone Alidori Giancarlo Gioia Lobbia Gaia Emanuela Gioia Lobbia 《Journal of organometallic chemistry》2008,693(6):996-1004
The new sodium bis(1-methyl-1H-imidazol-2-ylthio)acetate, Na[(S-tim)2CHCO2], has been prepared in ethanol solution using 2-mercapto-1-methylimidazole, dibromoacetic acid and NaOH. New di- and tri-organotin(IV) derivatives have been synthesized from reaction between SnRnCl4−n (R = Ph, Cy and nBu, n = 2-3) acceptors and Na[(S-tim)2CHCO2]. Complexes of the type {[κ1O-(S-tim)2CHCO2]SnR3} and related decarboxylated species {[κ2N,N-(S-tim)2CH2]SnR2Cl2} have been obtained and characterized by elemental analyses, FT-IR, ESIMS and multinuclear (1H, 13C and 119Sn) NMR spectral data. The adduct {κ1O-[(S-tim)2CHCO2]Sn(H2O)(C4H9)3} was characterized by single crystal X-ray studies. The dichloromethane reaction solution of {κ1O-[(S-tim)2CHCO2]Sn(C6H5)3} was re-crystallized and the decarboxylated species {[(S-tim)2CH2]SnCl(H2O)(C6H5)3} was obtained as a crystalline solid and characterized by X-ray crystallography. 相似文献
457.
Krzysztof Drwal Zuzanna Górska Patrycja Bończak Beata Krasnodębska-Ostręga 《Electroanalysis》2023,35(5):e202200397
The stripping voltammetry at HMDE is proposed for Cd and Pb (undesirable ingredients) determination in the natural brine (CCl >43 g L−1). Samples with so high salinity have to be significantly diluted. For ICP MS, a 105–6 times dilution is required, which disqualifies this method. The proposed procedure allows to determine Cd (0.001 μg L−1) and Pb (0.005 μg L−1) after only 100 times dilution. The thermal chloride stripping or isolation by Chelex 100 increase the quality of obtained data. The recovery study was performed. The LOQs are below recommendations related to the use of brines in balneology. 相似文献
458.
Multiple X‐ray approaches to discriminate the origin of liquefied sand erupted during the 2012 Emilia Romagna earthquake 下载免费PDF全文
Dario Di Giuseppe Umberto Tessari Barbara Faccini Massimo Coltorti Carmela Vaccaro Emanuela Marin 《X射线光谱测定》2016,45(1):19-27
Geochemical, mineralogical and sedimentological analyses were carried out on sands erupted from sand volcanoes and soil cracks during the 2012 Emilia earthquakes with the aim of determining their origin and depth of provenance in a complex stratigraphic plain generated by different fluvial contributions. Geochemical, mineralogical and sedimentological analyses were performed by wavelength dispersive X‐ray fluorescence, X‐ray powder diffraction and Sedigraph and Settling tube, respectively. Distinct textural features, as well as Ni/MgO and Cr/Al2O3 ratios, allow discriminating two populations: an A‐area located close to San Carlo village and a B‐area nearby Scortichino village. Sediments from A‐area show chemical and mineralogical characteristics well comparable with those of the sediments derived from the Apennine rivers, whereas sands from B‐area have strong similarities with the sediments from the Po river. In the earthquake crater area most of the liquefaction phenomena were related to superficial sandy deposits (fluvial ridges, paleochannels and crevasse splays) generated by Apennine rivers. The Po river sediments in the B‐area derive from a layer at a depth at which liquefaction phenomena were excluded, because of the greater lithostatic load. These sediments thus shed a new light on the mechanisms that may induce liquefaction during an earthquake or even without a seismic triggering. It is suggested that a gas phase (mainly methane), which is commonly found below the Po plain, could have been dissolved in the water, near to the saturation threshold or already exsolved, increasing the interstitial overpressure and facilitating the liquefaction and the eruption of the sandy sediments. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
459.
Sottani C Rinaldi P Leoni E Poggi G Teragni C Delmonte A Minoia C 《Rapid communications in mass spectrometry : RCM》2008,22(17):2645-2659
A reversed-phase high-performance liquid chromatography (rp-HPLC) system interfaced with an electrospray ionization (ESI) source coupled to tandem mass spectrometry (MS/MS) was developed and validated for the determination of cyclophosphamide (CP), ifosfamide (IF), daunorubicin (DNR), doxorubicin (DXR), and epirubicin (EPI) in human urine. The analysis of samples containing multiple analytes with a dissimilar range of polarities was carried out using a conventional reversed-phase chromatographic BDS Hypersil C8 column. The analytical run was 15 min. The triple quadrupole mass spectrometer was operated in positive ion mode and multiple reaction monitoring (MRM) was used for drug quantification. The method was validated over a concentration range of 0.2 to 4.0 microg.L(-1) for CP, IF, DXR, EPI and 0.15-2.0 microg.L(-1) for DNR in human urine. The lower limit of quantification (LLOQ) was 0.2 microg.L(-1) for CP, IF, EPI and was set at 0.3 and 0.15 microg.L(-1) for DXR and DNR, respectively. The relative standard deviations (RSD%) were <11.2% for inter- and intra-day precisions. The overall accuracy was also within 114.7% for all analytes at the concentrations of the quality control samples. The potential of ionization suppression resulting from the endogenous biological material on the rp-HPLC/MS/MS method was evaluated and measured. The feasibility of the proposed HPLC/ESI-MS/MS procedure was demonstrated by analyzing urine samples from pharmacy technicians and nurses working in hospitals or personnel employed in drug-manufacturing plants. 相似文献
460.
Emanuela S. Fioretta Joost O. Fledderus Ewelina A. Burakowska‐Meise Frank P. T. Baaijens Marianne C. Verhaar Carlijn V. C. Bouten 《Macromolecular bioscience》2012,12(5):577-590
In situ vascular tissue engineering has been proposed as a promising approach to fulfill the need for small‐diameter blood vessel substitutes. The approach comprises the use of a cell‐free instructive scaffold to guide and control cell recruitment, differentiation, and tissue formation at the locus of implantation. Here we review the design parameters for such scaffolds, with special emphasis on differentiation of recruited ECFCs into the different lineages that constitute the vessel wall. Next to defining the target properties of the vessel, we concentrate on the target cell source, the ECFCs, and on the environmental control of the fate of these cells within the scaffold. The prospects of the approach are discussed in the light of current technical and biological hurdles.