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991.
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992.
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
993.
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
994.
Cardoso JC Grimes CA Feng X Zhang X Komarneni S Zanoni MV Bao N 《Chemical communications (Cambridge, England)》2012,48(22):2818-2820
We report on low-cost, all solution fabrication of efficient air-stable nanostructured thin film photovoltaics comprised of n-type Sb(2)S(3) chemically deposited onto TiO(2) nanowire array films, forming coaxial Sb(2)S(3)/TiO(2) nanowire hybrids vertically oriented from the SnO(2):F coated glass substrate, which are then intercalated with poly(3-hexylthiophene) (P3HT) for hole transport and enhanced light absorption. 相似文献
995.
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
996.
A Russo M Migliorini L Cecchi C Cherubini M Giusti B Zanoni E Perri M Nardi G Sindona 《Journal of mass spectrometry : JMS》2012,47(9):1242-1246
Identification and assay of sugars in olive drupes during their ripening phase is evaluated by tandem mass spectrometry. Recent achievements have shown that the quality of an extra virgin olive oil can be directly correlated to the ripening degree of the drupes that is likely linked to their saccharides content. An innovation in this peculiar food chain is now proposed that considers a high throughput assessment of the carbohydrate content by a recently introduced protocol based on the gas-phase chemistry of sugar-cesium adducts by ESI-MS/MS. Copyright ? 2012 John Wiley & Sons, Ltd. 相似文献
997.
998.
Francesca Cagliari Maria Manuel Clementino Sandra Mantovani 《Journal of Pure and Applied Algebra》2012,216(11):2411-2424
Using Escardó’s characterization of injectivity via Kock–Zöberlein monads, we introduce suitable monads in comma categories of topological spaces that yield characterizations of fibrewise injectivity in topological T0-spaces, with respect to the class of embeddings, and of dense, of flat and of completely flat embeddings. Characterizations, in the category of topological spaces, of injective maps with respect to the same classes of embeddings follow easily from the results obtained for T0-spaces. Moreover, it is shown that, together with the corresponding embeddings, injective continuous maps form a weak factorization system in the category of topological (T0-)spaces and continuous maps. 相似文献
999.
1000.