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排序方式: 共有239条查询结果,搜索用时 265 毫秒
181.
Cristian Silvestru Anca Silvestru Ionel Haiduc Rubn Gavio Ramírez Raymundo Cea-Olivares 《Heteroatom Chemistry》1994,5(4):327-336
Tri- and diphenyllead(IV) diorganophosphinodithioates, PhnPb(S2PR2)4−n (n = 2 and 3; R = Me, Et, Ph) were prepared by reacting the corresponding organolead(IV) chloride with the sodium or ammonium salt of the phosphinodithioic acid. The title compounds were investigated by infrared, 1H and 31P NMR, and mass spectroscopy, and possible structures were proposed. The diphenyllead(IV) phosphinodithioates, Ph2Pb(S2PR2)2, undergo decomposition on standing or on moderate heating, the least stable being the ethyl derivative. The process was monitored by using 1H and 31P NMR spectroscopy, and a reaction pathway leading to Ph3PbS2PR2, Pb(S2PR2)2, and R2P(S)SPh was established. 相似文献
182.
Irina Macovei Simon Vlad Luca Krystyna Skalicka-Wo
niak Liviu Sacarescu Petronela Pascariu Alina Ghilan Florica Doroftei Elena-Laura Ursu Cristina Mihaela Rimbu Cristina Elena Horhogea Cristina Lungu Gabriela Vochita Alina Diana Panainte Constantin Nechita Maria Andreia Corciova Anca Miron 《Molecules (Basel, Switzerland)》2022,27(1)
Silver nanoparticles synthesized using plant extracts as reducing and capping agents showed various biological activities. In the present study, colloidal silver nanoparticle solutions were produced from the aqueous extracts of Picea abies and Pinus nigra bark. The phenolic profile of bark extracts was analyzed by liquid chromatography coupled to mass spectrometry. The synthesis of silver nanoparticles was monitored using UV-Vis spectroscopy by measuring the Surface Plasmon Resonance band. Silver nanoparticles were characterized by attenuated total reflection Fourier transform infrared spectroscopy, Raman spectroscopy, dynamic light scattering, scanning electron microscopy, energy dispersive X-ray and transmission electron microscopy analyses. The antimicrobial and cytogenotoxic effects of silver nanoparticles were evaluated by disk diffusion and Allium cepa assays, respectively. Picea abies and Pinus nigra bark extract derived silver nanoparticles were spherical (mean hydrodynamic diameters of 78.48 and 77.66 nm, respectively) and well dispersed, having a narrow particle size distribution (polydispersity index values of 0.334 and 0.224, respectively) and good stability (zeta potential values of −10.8 and −14.6 mV, respectively). Silver nanoparticles showed stronger antibacterial, antifungal, and antimitotic effects than the bark extracts used for their synthesis. Silver nanoparticles obtained in the present study are promising candidates for the development of novel formulations with various therapeutic applications. 相似文献
183.
Adriana Aurelia Chis Carmen Maximiliana Dobrea Luca-Liviu Rus Adina Frum Claudiu Morgovan Anca Butuca Maria Totan Anca Maria Juncan Felicia Gabriela Gligor Anca Maria Arseniu 《Molecules (Basel, Switzerland)》2021,26(19)
Gene-directed enzyme prodrug therapy (GDEPT) has been intensively studied as a promising new strategy of prodrug delivery, with its main advantages being represented by an enhanced efficacy and a reduced off-target toxicity of the active drug. In recent years, numerous therapeutic systems based on GDEPT strategy have entered clinical trials. In order to deliver the desired gene at a specific site of action, this therapeutic approach uses vectors divided in two major categories, viral vectors and non-viral vectors, with the latter being represented by chemical delivery agents. There is considerable interest in the development of non-viral vectors due to their decreased immunogenicity, higher specificity, ease of synthesis and greater flexibility for subsequent modulations. Dendrimers used as delivery vehicles offer many advantages, such as: nanoscale size, precise molecular weight, increased solubility, high load capacity, high bioavailability and low immunogenicity. The aim of the present work was to provide a comprehensive overview of the recent advances regarding the use of dendrimers as non-viral carriers in the GDEPT therapy. 相似文献
184.
Melinda Fogarasi Maria-Ioana Socaciu Claudiu-Dan Slgean Floricua Ranga Anca Corina Frca Sonia Ancua Socaci Carmen Socaciu Dorin
ibulc Szabolcs Fogarasi Cristina Anamaria Semeniuc 《Molecules (Basel, Switzerland)》2021,26(24)
Edible mushrooms are well-known for their nutritional benefits and low energy density. In addition, mushroom extracts contain various bioactive compounds that account for their antioxidant activity; the applied extraction conditions influence the extraction efficiency of such compounds. Therefore, this study investigates the effects of four extractants on the content of polyphenols and antioxidant properties of Boletus edulis and Cantharellus cibarius mushrooms, aiming to optimize the extraction process. Powders of B. edulis and C. cibarius mushrooms were subjected to extraction with acidic water (10% CH3COOH), ethanol/water/acetic acid (15:76.5:8.5, v/v/v), hexane, and diethyl ether to measure their total phenolic content (TPC), total flavonoid content (TFC), and Trolox equivalent antioxidant capacity (TEAC). Furthermore, the level of individual polyphenolic compounds in these extracts was quantified using an HPLC-DAD-ESI-MS method. Results showed that the type of solvent significantly influenced the TPC and TEAC of mushroom powder but insignificantly influenced the TFC. A very strong positive correlation was found between TPC and TEAC, but no correlation was found between TFC and TEAC or TPC and TFC. Acidic water extracted the highest amount of polyphenolic compounds from these mushroom powders. Therefore, the aqueous extract showed the highest TPC and strongest antioxidant activity. Thus, acidic water is recommended for polyphenol analysis in B. edulis and C. cibarius mushrooms. 相似文献
185.
Ledeți Ionuț Bengescu Cosmina Cîrcioban Denisa Vlase Gabriela Vlase Titus Tomoroga Carmen Buda Valentina Ledeți Adriana Dragomirescu Anca Murariu Marius 《Journal of Thermal Analysis and Calorimetry》2020,141(3):1053-1065
Journal of Thermal Analysis and Calorimetry - In the class of steroid hormones, glucocorticoids are belonging to the subclass of corticosteroids, consisting of numerous synthetic or naturally... 相似文献
186.
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188.
Silvana Maione Georgina Fabregat Luis J. del Valle Anca‐Dana Bendrea Luminita Cianga Ioan Cianga Francesc Estrany Carlos Alemán 《Journal of Polymer Science.Polymer Physics》2015,53(4):239-252
Graft copolymers formed by anchoring poly(ethylene glycol) (PEG) chains to conjugated polythiophene have been prepared by copolymerizing two compounds: unsubstituted α‐terthiophene (Th3) and a thiophene‐derived macromonomer having an α‐terthiophene conjugated sequence and one Th3 bearing a PEG chain with molecular weight of 2000 as substitute at the 3‐position of the central heterocycle (Th3‐PEG2000). The grafting ratio of the resulting copolymers (PTh3*‐g‐PEG), which were obtained using 75:25 and 50:50 Th3‐PEG2000:Th3 weight ratios, is significantly smaller than that of copolymers derived from polymerization of macromonomers consisting of a α‐pentathiophene sequence in which the central ring bears a PEG chain of Mw = 2000 (PTh5‐g‐PEG). The electroactivity and electrochemical stability of PTh3*‐g‐PEG is not only higher than that of PTh5‐g‐PEG but also higher than that of PTh3, the latter presenting a very compact structure that makes difficult the access and escape of dopant ions into the polymeric matrix during the redox processes. Furthermore, the optical π‐π* lowest transition energy of PTh3*‐g‐PEG is lower than that of both PTh5‐g‐PEG and PTh3. These properties, combined with suitable wettability and roughness, result in an excellent behavior as bioactive platform of PTh3*‐g‐PEG copolymers, which are more biocompatible, in terms of cellular adhesion and proliferation, and electro‐compatible than PTh5‐g‐PEG. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 239–252 相似文献
189.
Tănase Ionuț-Mihai Sbârcea Laura Ledeți Adriana Vlase Gabriela Barvinschi Paul Văruţ Renata-Maria Dragomirescu Anca Axente Carmen Ledeți Ionuț 《Journal of Thermal Analysis and Calorimetry》2020,141(3):1027-1039
Journal of Thermal Analysis and Calorimetry - Aripiprazole (ARP), an innovative atypical antipsychotic drug, exhibits very low aqueous solubility, affecting its dissolution and absorption and high... 相似文献
190.