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21.
L Castellano M Calandra C Del Vecchio Blanco I de Sio 《Canadian Metallurgical Quarterly》1997,27(5):862-870
BACKGROUND/AIMS: This study was undertaken to determine the factors predicting survival and intrahepatic recurrence in hepatocellular carcinoma patients treated with percutaneous ethanol injection. METHODS: Seventy-one patients with cirrhosis and hepatocellular carcinoma underwent percutaneous ethanol injection (54 males/17 females; median age 66 years; Child A 54/B 17). Fifty-two patients had a single nodule < or = 5 cm and 19 had multiple nodules, up to three, each one < or = 4 cm. Follow-up ranged from 2-63 months (median 26). RESULTS: Overall survival rates were 89%, 54% and 24% and new lesions recurrence rates 32%, 73% and 81% at 1, 3 and 5 years, respectively. At univariate analysis, monofocal tumor (p<0.05), absence of ascites (p<0.05), complete tumor necrosis at CT-scan or MRI (p<0.01), post-treatment alpha-fetoprotein < or = 10 ng/ml (p<0.05) and Child A class in patients with a single nodule (p<0.05) were associated with higher survival. Presence of tumor capsule at imaging (p<0.05), complete tumor necrosis at CT-scan or MRI (p<0.01) and post-treatment alpha-fetoprotein < or = 10 ng/ml (p<0.01) were associated with lower recurrence rates. At multivariate analysis, basal alpha-fetoprotein (p=0.040) and tumor number (p=0.032) significantly affected survival; stepwise analysis revealed basal alpha-fetoprotein, tumor number and serum albumin (p=0.0012) as the best combination predicting survival. No variable reliably predicted recurrence by multivariate analysis. CONCLUSIONS: In patients with cirrhosis and hepatocellular carcinoma, treated with percutaneous ethanol injection, survival depends on: the severity of the underlying liver disease, uni/multifocality of the tumor and basal alpha-fetoprotein. Presence of a tumor capsule is associated with lower recurrence rates. At post-treatment evaluation, both survival and recurrence rates are positively affected by complete tumor necrosis and alpha-fetoprotein < or = 10 ng/ml. 相似文献
22.
Paola Fabbri Graldine Champon Maila Castellano Mohamed Naceur Belgacem Alessandro Gandini 《Polymer International》2004,53(1):7-11
Various lignocellulosic substrates, including microcrystalline cellulose, pinewood and hemp fibres, were treated with triethylaluminium and triethylboron in suspensions, in non‐swelling media. Chemical and spectroscopic analyses show that coupling surface reactions took place between one or two metal‐to‐carbon (Mt–C) bonds and the OH groups of the natural polymers. The remaining unreacted Mt–C bonds were exploited to graft numerous molecular structures derived from alcohols and amines. The occurrence of the second reaction was proved by Fourier‐transform infrared spectroscopy, elemental analyses, X‐ray photoelectron spectroscopy and contact angle measurements. Copyright © 2004 Society of Chemical Industry 相似文献
23.
G Galizia E Lieto P Castellano F Canfora R Tolomeo L Pelosio V Imperatore G Candela 《Canadian Metallurgical Quarterly》1997,49(3):51-72
Radical treatment of the hepatocellular carcinoma (HCC) is complete surgical removal; it may be done by resection or total hepatectomy. Although multicentric carcinogenesis predicts that liver transplantation is likely adequate to treat both the hepatoma and the underlying cirrhosis, it doesn't seem justified in the advanced stages or in absence of end-stage liver disease and therefore liver resection remains the treatment of choice for radical cure of HCC. However, low resectability and high recurrence rate make surgery alone ineffective. Unresectable HCC may be converted to resectable by multimodality radiation/chemotherapy, and embolization of portal branch feeding tumour, improving the function of the nonembolized liver, can extend the surgical indications for HCC. Adjuvant chemoembolization has already shown to reduce recurrence rate after radical resection and it should be widely applied. In unresectable or not converted HCCs as well as in postoperative recurrence, alternative therapies, particularly as multimodality treatment, can improve survival rate. To date, multidisciplinary treatment of hepatocellular carcinoma, waiting for further studies on newer modalities (prevention and gene therapy, especially), represents the best way to improve long-term results. 相似文献
24.
C. Castellano F. Cordero O. Palumbo R. Cantelli A. Martinelli M. Ferretti 《Journal of Superconductivity》2005,18(5-6):43-47
We report extended X-ray absorption fine structure measurements at the Mn K edge on La0.25Ca0.75Mn0.92Cr0.08O3 samples. Macroscopically, the Mn substitution induces a short-range charge-ordered state in spite of the long-range one present in the parent manganite La0.25Ca0.75MnO3. We show how on a local scale the structural EXAFS parameters still confirm the presence, with only a slight reduction, of the features characteristic of the charge ordered un-substituted compounds. 相似文献
25.
Enhancement in Organic Photovoltaic Efficiency through the Synergistic Interplay of Molecular Donor Hydrogen Bonding and π‐Stacking 下载免费PDF全文
Nathan T. Shewmon Davita L. Watkins Johan F. Galindo Raghida Bou Zerdan Jihua Chen Jong Keum Adrian E. Roitberg Jiangeng Xue Ronald K. Castellano 《Advanced functional materials》2015,25(32):5166-5177
For organic photovoltaic (OPV) cells based on the bulk heterojunction (BHJ) structure, it remains challenging to rationally control the degree of phase separation and percolation within blends of donors and acceptors to secure optimal charge separation and transport. Reported is a bottom‐up, supramolecular approach to BHJ OPVs wherein tailored hydrogen bonding (H‐bonding) interactions between π‐conjugated electron donor molecules encourage formation of vertically aligned donor π‐stacks while simultaneously suppressing lateral aggregation; the programmed arrangement facilitates fine mixing with fullerene acceptors and efficient charge transport. The approach is illustrated using conventional linear or branched quaterthiophene donor chromophores outfitted with terminal functional groups that are either capable or incapable of self‐complementary H‐bonding. When applied to OPVs, the H‐bond capable donors yield a twofold enhancement in power conversion efficiency relative to the comparator systems, with a maximum external quantum efficiency of 64%. H‐bond promoted assembly results in redshifted absorption (in neat films and donor:C60 blends) and enhanced charge collection efficiency despite disparate donor chromophore structure. Both features positively impact photocurrent and fill factor in OPV devices. Film structural characterization by atomic force microscopy, transmission electron microscopy, and grazing incidence wide angle X‐ray scattering reveals a synergistic interplay of lateral H‐bonding interactions and vertical π‐stacking for directing the favorable morphology of the BHJ. 相似文献
26.
27.
Cosmelli C. Carelli P. Castellano M. Foglietti V. 《IEEE transactions on magnetics》1987,23(2):454-457
We have coupled a very low noise dc-SQUID to the gravitational radiation detector of the Rome group at CERN laboratories. The SQUID used is a multiloop thin-film device with an input inductance of 1.6 μH, loop inductance of 5 pH and coupling coefficient of 0.5. The gravitational radiation detector is composed by a 2.3 tons Aluminum cylinder mechanically coupled to a resonant capacitive transducer; this is matched to the SQUID by means of a large superconducting transformer. The signal to be detected is essentially composed by the two mode frequencies at about 1 kHz and with quality factors of the order of 4×106. To operate in a closed feedback loop mode we have used a particular setup in order not to degrade the performance of the system. The system operated for seven months with some interruptions due to refilling of liquid helium and various tests on the apparatus. The flux noise obtained was 1.5 to3times10^{-6} Phi_{o}/sqrt{Hz} at 1 kHz with a linearity over 6 orders of magnitude and a long term stability of1.5 times 10^{-8} Phi_{o} /hour. 相似文献
28.
29.
The effects of elevated blood lead on semen quality were evaluated in the rabbit model and compared to published effects in humans. Mature, male rabbits were given lead acetate by subcutaneous injection in the dose range of 0 to 3.85 mg/kg on a Monday-Wednesday-Friday basis. In each of eight treatment groups, a dosing regimen was developed to produce blood lead levels of 0, 20, 40, 50, 70, 80, 90, and 110 microg/dL. A 5-week pre-exposure period was followed by a 15-week exposure testing period allowing for response through six cycles of the seminiferous epithelium. Semen analyses revealed that increased blood lead levels were associated with adverse changes in the sperm count, ejaculate volume, percent motile sperm, swimming velocities, and morphology. Hormonal responses were minimal. Testicular pathology revealed a dose-dependent inhibition of spermiation. For six measures of semen quality, threshold estimates ranged from 16 to 24 microg/dL. Using the species extrapolation factor derived in this study, a rabbit dose would have to be divided by 1.56 to obtain the equivalent human dose for an equal percentage decrease in sperm concentration; however, rabbits are 3.75 more sensitive in terms of absolute decrease in sperm count for a given blood lead level. 相似文献
30.
R. Leoni P. Carelli M. G. Castellano D. Peschiaroli C. Berger A. Gabutti S. Janos K. Pretzl 《Journal of Low Temperature Physics》1993,93(3-4):503-508
We report on improvements of the dc-SQUID instrumentation developed to study superheating-supercooling transitions of thin-film indium dots. In previous measurements on ordered arrays of dots with diameters larger than 100µm the flip signal of an individual dot in perpendicular magnetic field has been detected. In order to use these dots as superheated superconducting detectors it is necessary to reduce the dot diameter to lower the energy threshold and to avoid intermediate states. For these reasons, our effort has been to develop small and thick dots with diameter down to10 µm and thickness up to3.5 µm. At the same time the coupling with the dc-SQUID readout was improved using a thin-film niobium pickup coil integrated on the same chip containing the dots. Phase transitions of individual dots were observed. The superheating phase transition spread in temperature of the samples was about 0.15 %. 相似文献