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51.
Marco Moschetta Michele Telegrafo Leonarda Rella Amato Antonio Stabile Ianora Giuseppe Angelelli 《Magnetic resonance imaging》2014
Objectives
Diffusion-weighted imaging with background body signal suppression (DWIBS) provides both qualitative and quantitative imaging of breast lesions and are usually performed before contrast material injection (CMI). This study aims to assess whether the administration of gadolinium significantly affects DWIBS imaging.Methods
200 patients were prospectively evaluated by MRI with STIR, TSE-T2, pre-CMI DWIBS, contrast enhanced THRIVE-T1 and post-CMI DWIBS sequences. Pre and post-CMI DWIBS were analyzed searching for the presence of breast lesions and calculating the ADC value. ADC values of ≤ 1.44 × 10- 3 mm2/s were considered suspicious for malignancy. This analysis was then compared with the histological findings. Sensitivity, specificity, diagnostic accuracy (DA), positive predictive value (PPV) and negative (NPV) were calculated for both sequences and represented by ROC analysis. Pre and post-CMI ADC values were compared by using the paired t test.Results
In 150/200 (59%) patients, pre and post-CMI DWIBS indicated the presence of breast lesions, 53 (35%) with ADC values of > 1.44 × 10- 3 mm2/s and 97 (65%) with ADC ≤ 1.44 × 10- 3 mm2/s. Pre-CMI and post-DWIBS sequences obtained the same sensitivity, specificity, DA, PPV and NPV values of 97%, 83%, 89%, 79% and 98%. The mean ADC value of benign lesions was 1.831 ± 0.18 × 10- 3 mm2/s before and 1.828 ± 0.18 × 10- 3 mm2/s after CMI. The mean ADC value of the malignant lesions was 1.146 ± 0.16 × 10- 3 mm2/s before and 1.144 ± 0.16 × 10- 3 mm2/s after CMI. No significant difference was found between pre and post CMI ADC values (p > 0.05).Conclusion
DWIBS imaging is not influenced by CMI. Breast MR protocol could be modified by placing DWIBS after dynamic contrast enhanced sequences in order to maximize patient cooperation. 相似文献52.
We report on the integration of a size-based three-dimensional filter, with micrometre-sized pores, in a commercial microfluidic chip. The filter is fabricated inside an already sealed microfluidic channel using the unique capabilities of two-photon polymerization. This direct-write technique enables integration of the filter by post-processing in a chip that has been fabricated by standard technologies. The filter is located at the intersection of two channels in order to control the amount of flow passing through the filter. Tests with a suspension of 3 μm polystyrene spheres in a Rhodamine 6G solution show that 100% of the spheres are stopped, while the fluorescent molecules are transmitted through the filter. We demonstrate operation up to a period of 25 minutes without any evidence of clogging. Preliminary validation of the device for plasma separation from whole blood is shown. Moreover, the filter can be cleaned and reused by reversing the flow. 相似文献
53.
V D'Atri G Oliviero J Amato N Borbone S D'Errico L Mayol V Piccialli S Haider B Hoorelbeke J Balzarini G Piccialli 《Chemical communications (Cambridge, England)》2012,48(76):9516-9518
This communication reports on the synthesis and biophysical, biological and SAR studies of a small library of new anti-HIV aptamers based on the tetra-end-linked G-quadruplex structure. The new aptamers showed EC(50) values against HIV-1 in the range of 0.04-0.15 μM as well as affinities for the HIV-1 gp120 envelope in the same order of magnitude. 相似文献
54.
Andrea Pappalardo Maria E. Amato Francesco P. Ballistreri Anna Notti Gaetano A. Tomaselli Rosa M. Toscano Giuseppe Trusso Sfrazzetto 《Tetrahedron letters》2012,53(52):7150-7153
Chiral diastereomeric cavitand-salen macrocycles have been synthesized by the high-dilution condensation of a tris-(quinoxaline-bridged)-diformyl-calix[4]resorcarene with (1R,2R)-diphenylethylenediamine. The reaction produced a couple of diastereoisomers, consisting of two cavitand cavities bis-bridged by two chiral diimino moieties, which differ in a convergent (C-shaped) or divergent (S-shaped) orientation of the two cavities. 相似文献
55.
A Pappalardo ME Amato FP Ballistreri GA Tomaselli RM Toscano G Trusso Sfrazzetto 《The Journal of organic chemistry》2012,77(17):7684-7687
A pair of diastereomeric salen cavitands and their uranyl complexes combine a chiral (R,R) salen bridge and an inherent chiral tris-bridged quinoxaline cup within the same molecule. Whereas the free ligands show a preference for the same enantiomer of an α-amino acid pair, the corresponding UO(2) complexes display opposite enantiodiscrimination and exceptionally high enantioselectivities (K(D)/K(L) = 26.4). 相似文献
56.
A. Amato R. Feyerherm F.N. Gygax A. Schenck M. Kasaya T. Suzuki S. Takagi A. Ochiai 《Hyperfine Interactions》1997,104(1-4):165-170
We report on μSR studies in low charge carrier density heavy‐fermion systems with cubic symmetry. Whereas for Ce3Au3Sb_4 and for Sm3Te4 the μSR data point to the presence of some kind of spin‐glass‐like magnetic states at low temperature, for Yb4As3 preliminary μSR studies just show a slight increase of the depolarization rate which indicates a slight slowing down of the
Yb‐moment fluctuations. Consequently for this latter system, the large linear term of the specific heat seems indeed to be
connected to electronic excitations.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
57.
Identification of cosmetic dyes by ion-pair reversed-phase high-performance liquid chromatography 总被引:1,自引:0,他引:1
L Gagliardi G Cavazzutti A Amato A Basili D Tonelli 《Journal of chromatography. A》1987,394(2):345-352
A method based on ion-pair reversed-phase high-performance liquid chromatography with detection at four wavelengths between 400 and 600 nm is reported for the separation and identification of the most common synthetic colour additives in cosmetic products. All the dyes generally employed in the U.S.A. and almost all those in current use in cosmetics in the European Community have been taken into account. The chromatography was performed on a C8 bonded silica packed column, with a 60-min gradient changing from 10 to 95% acetonitrile in water containing 10(-2) M sodium perchlorate (pH 3.0) as mobile phase (flow-rate 2.5 ml/min). Detection limits are in the range 20-100 ng for all dyes investigated. The method has been applied to the analysis of commercial lipsticks. 相似文献
58.
Summary Daily global solar-radiation sequences are studied for Italy. We show that the experimental data can be described as a first-order
autoregressive stochastic process independent of locality or season: the only climatic information needed is the monthly average
of the clearness index. We also show that the clearness index sequences can be transformed in sequences with normal distribution
but with the same autocorrelation properties; it is then easy to construct synthetic sequences of radiation data with the
same statistical properties as the real data, useful for performance prediction of solar systems.
相似文献
Riassunto Si analizzano le serie temporali dei valori giornalieriK T (rapporto tra la radiazione solare globale su superficie orizzontale e la radiazione extra-atmosferica) per il territorio italiano. Si dimostra che i dati possono essere descritti con processi stocastici autoregressivi del primo ordine indipendentemente dalla località o stagione: la sola informazione necessaria è il valore medio mensile dei rapportiK T . Si dimostra inoltre che le successioni dei valoriK T possono essere trasformate in successioni con funzione di distribuzione normale e con le stesse caratteristiche statistiche di autocorrelazione dei dati originari; in tal modo è poi possibile costruire successioni di dati di radiazione, di lunghezza pari al numero di giorni in un mese e con le stesse proprietà statistiche dei dati sperimentali, utili per il calcolo delle prestazioni di sistemi solari.
相似文献
59.
60.
The transverse field μSR-signal from μ+ implanted in a CeAs single crystal shows a splitting into two components, displaying a positive and a negative Knight shift,
respectively which both scale reasonably well with the magnetic bulk susceptibility above 10 K. The orientation dependence
of the frequency shifts, measured at 15 K, is fully accounted for by the demagnetization field, implying an isotropic Knight
shift, consistent with the μ+ residing at the only interstitial site of high (cubic) symmetry, i.e., at the position (1/4,1/4,1/4). The occurrence of a
split signal remains unexplained.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献