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971.
García-Gallego S Rodríguez JS Jiménez JL Cangiotti M Ottaviani MF Muñoz-Fernández MÁ Gómez R de la Mata FJ 《Dalton transactions (Cambridge, England : 2003)》2012,41(21):6488-6499
We describe here the synthesis and characterization of new sulfonated and carboxylated-containing N-donor ligands [Na(4)(edts)]·4H(2)O (2), [Na(2)(dmeddp)]·2H(2)O (3) and [Na(4)(edtp)]·H(2)O (4) (edts = ethylene-diamine- N,N,N',N'-tetraethylenesulfonate ion; dmeddp = dimethyl-ethylene-diamine-N,N,N',N'-tetra-3-propionate ion; edtp = ethylene-diamine-N,N,N',N'-tetra-3-propionate ion) and their corresponding metal (Ni, Co, Cu and Zn) complexes. Mainly, UV-Vis and a computer aided analysis of the EPR spectra provided information on the geometry and structure of the complexes in solution. Some of the metal complexes inhibit HIV replication when treating both pre- and post-infected PBMC cells, and hustle the inhibitory effect compared to the metal salts alone. 相似文献
972.
M D'Onofrio E Gianolio A Ceccon F Arena S Zanzoni D Fushman S Aime H Molinari M Assfalg 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(32):9919-9928
Gadolinium complexes linked to an apolar fragment are known to be efficiently internalized into various cell types, including hepatocytes. Two lipid-functionalized gadolinium chelates have been investigated for the targeting of the human liver fatty acid binding protein (hL-FABP) as a means of increasing the sensitivity and specificity of intracellular-directed MRI probes. hL-FABP, the most abundant cytosolic lipid binding protein in hepatocytes, displays the ability to interact with multiple ligands involved in lipid signaling and is believed to be an obligate carrier to escort lipidic drugs across the cell. The interaction modes of a fatty acid and a bile acid based gadolinium complex with hL-FABP have been characterized by relaxometric and NMR experiments in solution with close-to-physiological protein concentrations. We have introduced the analysis of paramagnetic-induced protein NMR signal intensity changes as a quantitative tool for the determination of binding stoichiometry and of precise metal-ion-center positioning in protein-ligand supramolecular adducts. A few additional NMR-derived restraints were then sufficient to locate the ligand molecules in the protein binding sites by using a rapid data-driven docking method. Relaxometric and (13)C NMR competition experiments with oleate and the gadolinium complexes revealed the formation of heterotypic adducts, which indicates that the amphiphilic compounds may co-exist in the protein cavity with physiological ligands. The differences in adduct formation between fatty acid and bile acid based complexes provide the basis for an improved molecular design of intracellular targeted probes. 相似文献
973.
Lucia Manganaro Giorgio Vittori Valeria Vinci Francesca Fierro Alessandra Tomei Pietro Lodise Paolo Sollazzo Maria E. Sergi Silvia Bernardo Laura Ballesio Mario Marini Maria G. Porpora 《Magnetic resonance imaging》2012
Objectives
Endometriosis is the ectopic localization of endometrial glands. Symptoms include a wide variety of chronic pelvic pain. Ovarian endometriosis represents the most frequent site of implantation followed by the Douglas pouch which is undepicted unless peritoneal fluid is present. Pelvic exams may be reported as normal in 40% of evaluations, although multiple nodularities are located in this region. Nowadays, laparoscopy represents the standard technique for endometriosis evaluation. However, magnetic resonance imaging (MRI) remains the best noninvasive technique for the evaluation of pelvic lesions. According to the importance of a precise preoperative diagnosis of deep infiltrative endometriosis involving the Douglas pouch, we evaluated feasibility of a 3-T system in the evaluation of this particular region.Methods
We enrolled 19 women coming with either ultrasound or anamnestic suspicion of endometriosis. Pelvic MRI examination was performed on the 3-T system. We applied a standard exam protocol including pulse sequences [single-shot fast spin echo (FSE)] and high-resolution T2W and T1W FSE sequences with and without FS.Results
MRI diagnosed posterior cul-de-sac obliteration in 15/19 patients. MRI findings were compared with laparoscopy, thus obtaining the following statistical values: mean sensitivity, specificity, positive predictive value and negative predictive value, respectively, of 93%, 75%, 93% and 75%. Moreover, we calculated an interobserver agreement k value of 0.72 with a substantial degree of agreement between two radiologists of a sensitivity value of 93% and specificity value of 75%.Conclusions
Precise preoperative mapping of posterior cul-de-sac region is essential for a preoperative planning. In our work, the 3-T MRI was shown to be excellent in the evaluation of posterior cul-de-sac obliteration associated to an optimal evaluation of the uterosacral ligaments due to the higher contrast spatial resolution. 相似文献974.
Francesco Caruso Steven Saverwyns Marina Van Bos Delia Francesca Chillura?Martino Anne-Emmanuelle Ceulemans Joris de Valck Eugenio Caponetti 《Applied Physics A: Materials Science & Processing》2012,107(1):197-202
In recent years, a growing attention has been addressed to the study of the varnish from early musical instruments. The surfaces
of nine historical Low Countries stringed musical instruments from the collection of the “Musical Instruments Museum” in Brussels
were non-destructively analysed by in situ micro-X-Ray Fluorescence spectroscopy in dispersive mode. It was found that the
main pigments dispersed in the varnish were iron- and manganese-based earths. The presence of a chromium-based pigment in
one of the analysed instruments makes it appreciably different from the others. Other findings were discussed and compared
with previously published results. The collection of such information plays a relevant role in the recovery of the applied
formulations that is an interesting issue for conservators, luthiers and art historians. 相似文献
975.
Estradé S Portillo J Mendoza J Kosta I Serret M Müller C Peiró F 《Micron (Oxford, England : 1993)》2012,43(8):910-915
Precession electron diffraction (PED) allows for diffraction pattern collection under quasi-kinematical conditions. The combination of PED with fast electron diffraction acquisition and pattern matching software techniques is used for the high magnification ultra-fast mapping of variable crystal orientations and phases, similarly to what is achieved with the Electron Backscattered Diffraction technique in Scanning Electron Microscopes at lower magnifications and longer acquisition times. Here we report, for the first time, the application of this PED-based orientation mapping technique to both metallic and semiconducting nanowires. 相似文献
976.
Highly stable gel electrolytes for dye solar cells based on chemically engineered polymethacrylic hosts 总被引:1,自引:0,他引:1
De Gregorio GL Agosta R Giannuzzi R Martina F De Marco L Manca M Gigli G 《Chemical communications (Cambridge, England)》2012,48(25):3109-3111
Four different species of ionically conductive polymers were synthesized and successfully implemented to formulate novel quasi-solid electrolytes for dye solar cells. A power conversion efficiency superior to 85% of the correspondent liquid electrolyte as well as an excellent cell's stability was demonstrated after 500 days of storage. 相似文献
977.
978.
979.
980.
In this paper, numeration systems defined by recurrent sequences are considered. We present a class of recurrences yielding numeration systems for which the words corresponding to greedy expressions for natural numbers are easily described. Those sequences, in turn, enumerate classes of words with forbidden substrings. 相似文献