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排序方式: 共有515条查询结果,搜索用时 781 毫秒
41.
G Martino M Filippi V Martinelli E Brambilla C Gobbi G Comi LM Grimaldi 《Canadian Metallurgical Quarterly》1997,63(3):339-345
42.
Elizaveta Kon Giuseppe Filardo Francesco Perdisa Alessandro Di Martino Maurizio Busacca Federica Balboni Andrea Sessa Maurilio Marcacci 《Journal of materials science. Materials in medicine》2014,25(10):2437-2444
The increasing interest in the role of subchondral bone with regard to articular surface disease led to the development of new bioengineered strategies. Aim of this study is to evaluate the clinical and MRI outcome after the implantation of a nanostructured biomimetic three-phasic collagen–hydroxyapatite construct for the treatment of chondral and osteochondral defects of the knee in a large cohort of patients. Seventy-nine patients (63 M, 16 W), affected by grade III–IV femoral condyle or trochlea chondral lesions or osteochondritis dissecans (OCD) were consecutively treated. Mean age was 31.0 ± 11.3 years, mean lesion size was 3.2 ± 2.0 cm2. Fifty patients underwent previous surgeries, concurrent procedures were necessary in 39 cases. The clinical outcome was evaluated using the IKDC and Tegner scores at 12 and 24 months of follow-up. At follow-up times an MRI was performed and evaluated with the MOCART score. All the scores improved significantly from the baseline. IKDC subjective score showed a further increase between 12 and 24 months of follow-up, and 82.2 % of the patients improved their symptoms at the final evaluation. Patients affected by OCDs had better results than those with degenerative lesions. Some abnormal MRI findings were present, even though no correlation was found with the clinical outcome. This one-step biomimetic approach developed to favor osteochondral tissue regeneration is effective in treating knees affected by damages of the articular surface, leading to a significant clinical improvement. However, abnormal MRI findings were present, even if not correlated with the clinical outcome. 相似文献
43.
M. VenturiniA. Filevich R. PizarroJ. Ibáñez P. BauleoJ. Rodríguez Martino 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,659(1):169-174
Fourteen years ago, studies on bacteria growing in clean water were made in order to assess the hazard imposed by a possible expansion of bacteria population in the water tanks of the Pierre Auger Observatory Cherenkov detectors. In 1999 TANGO Array, a reduced-size unitary cell, composed of four water Cherenkov detectors, was constructed at the TANDAR campus of the Atomic Energy Commission, in Buenos Aires, to be used as a working model of the proposed surface array. TANGO Array ran for one year observing energy, intensity, and arrival directions of cosmic rays at sea level. Nine years after it was decommissioned, the water tanks configuring the Cherenkov detectors are still kept closed. In May 2009 water and liner samples from these tanks were collected to determine eventual long term bacteria growth in the internal detector environment, which is very similar to those of the detectors installed in the Malargüe Site.In the present note we report the results of the bacteriological study performed on the samples obtained from the TANGO Array detector tanks. Cultivable, long time surviving, bacterial species were identified, both in the water mass and on the liner surface, and the light transmission in water at the relevant Cherenkov wavelength was studied. An upper limit of possible interferences caused by bacteria is estimated. 相似文献
44.
Alessandrini M Maggio S Porée J De Marchi L Speciale N Franceschini E Bernard O Basset O 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2011,58(11):2344-2360
Ultrasonic tissue characterization has become an area of intensive research. This procedure generally relies on the analysis of the unprocessed echo signal. Because the ultrasound echo is degraded by the non-ideal system point spread function, a deconvolution step could be employed to provide an estimate of the tissue response that could then be exploited for a more accurate characterization. In medical ultrasound, deconvolution is commonly used to increase diagnostic reliability of ultrasound images by improving their contrast and resolution. Most successful algorithms address deconvolution in a maximum a posteriori estimation framework; this typically leads to the solution of l(2)-norm or (1)-norm constrained optimization problems, depending on the choice of the prior distribution. Although these techniques are sufficient to obtain relevant image visual quality improvements, the obtained reflectivity estimates are, however, not appropriate for classification purposes. In this context, we introduce in this paper a maximum a posteriori deconvolution framework expressly derived to improve tissue characterization. The algorithm overcomes limitations associated with standard techniques by using a nonstandard prior model for the tissue response. We present an evaluation of the algorithm performance using both computer simulations and tissue-mimicking phantoms. These studies reveal increased accuracy in the characterization of media with different properties. A comparison with state-of-the-art Wiener and l(1)-norm deconvolution techniques attests to the superiority of the proposed algorithm. 相似文献
45.
Maurus Biedermann Jan‐Erik Ingenhoff Martino Barbanera Davide Garbini Koni Grob 《Packaging Technology and Science》2011,24(5):281-290
From the toxicological evaluation of mineral oils as used in offset printing inks by the Joint Food and Agriculture Organization of the United Nations/World Health Organization Expert Committee on Food Additives (JECFA), a specific migration limit of 0.6 mg/kg in food can be derived. Experimental packs for taglioline (fine noodles) were investigated, aiming at respecting this limit. This ended with four conclusions. First, during the 65 day test (shelf life of 2 years), the transport box of corrugated board contaminated the bottom packs in the box with 6.1 mg/kg mineral oil saturated hydrocarbons (MOSH) and had the potential of contaminating all the 10 packs on average at about 10 mg/kg. Second, the migration from an improved recycled paperboard (five times less mineral oil than average) still amounted to 4.9 mg/kg, indicating that optimization of recycling is not promising to respect the 0.6 mg/kg limit. Third, a printing ink containing 3 g/kg MOSH (about 100 times less than conventional offset inks) still contaminated the taglioline with 0.6 mg/kg MOSH. Finally, the taglioline were contaminated with 2.5 mg/kg MOSH already before packing, illustrating that there are other sources of mineral oil violating the 0.6 mg/kg limit. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
46.
Thermal, microstructural and textural characterisation of gelatinised corn, cassava and yam starch blends 总被引:1,自引:0,他引:1
Laura B. Karam Cristina Ferrero Miriam N. Martino Noemi E. Zaritzky & María Victoria E. Grossmann 《International Journal of Food Science & Technology》2006,41(7):805-812
The functional properties of mixtures of maize, cassava and yam starches and their relationships with microstructural characteristics were investigated. Experiments were performed following the simplex‐centroid design with internal points and restrictions (upper limit) for yam starch proportion. The statistical model used (Scheffé canonical equation) was a powerful tool to predict the pastes behaviour within the limits of the experimental area. Polynomials with second level interactions were applied to obtain the surface response. Viscoelastic attributes of mixtures differed from those of individual starches. As shown by differential scanning calorimetry and microscopical observations, physical properties of the mixtures depended on the type of networks obtained. These networks varied upon yam, corn and cassava starch proportions as each one has a particular characteristic: gelatinisation temperature, granule size, swelling capacity and amylose/amylopectin ratio among others. 相似文献
47.
Schell Terry L.; Martino Steven C.; Ellickson Phyllis L.; Collins Rebecca L.; McCaffrey Daniel 《Canadian Metallurgical Quarterly》2005,19(2):217
The goal of this study was to measure shifts in alcohol expectancies from childhood into adolescence while controlling for changes in the psychometric properties of the instrument. One thousand nine hundred ninety-three 4th-grade and 1,632 9th-grade students from South Dakota rated the likelihood that 23 outcomes would result from alcohol use. These expectancies were modeled using a 2-factor confirmatory factor analysis. After differences in the psychometric properties of the instrument were controlled, the cohorts were distinguished by a large difference in Alcohol Positivity, with older participants viewing alcohol's effects more positively. Additionally, older participants displayed greater Alcohol Potency, believing that alcohol has a larger impact on all outcomes. There were also significant differences in the interpretation of the alcohol expectancies items across cohorts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
F Pacini F Cetani P Miccoli F Mancusi C Ceccarelli F Lippi E Martino A Pinchera 《Canadian Metallurgical Quarterly》1994,18(4):600-604
From 1969 to 1990 there were 309 patients with differentiated thyroid carcinoma (241 papillary and 68 follicular) treated with radioactive iodine for functioning node metastases alone (n = 191) or distant metastases (n = 118) with or without node metastases. These patients represented 32.7% of 945 patients treated in our institution during the same period. Initial treatment included near-total thyroidectomy and 131I ablation of postsurgical thyroid residue, followed by L-thyroxine suppressive therapy. At the end of follow-up (mean 5.8 years), 146 patients (76.4%) in the group with nodal metastases were considered cured, as assessed by clinical and laboratory evaluation including whole body scan (WBS) and serum thyroglobulin (Tg) levels; 32 patients (16.7%) had persistent disease. Loss of 131I uptake in persistent metastatic lesions occurred in five patients (2.6%), and newly developed distant metastases occurred in eight patients (4.2%). Of the patients with distant metastases, 36.4% were cured by 131I. Distant metastases from papillary carcinomas had a higher cure rate than follicular carcinomas (p < 0.01). The metastases of four patients (5.2%) lost the property to take up radioiodine. Lung and bone metastases detectable by WBS but not by radiography were most likely to be cured by 131I. The overall survival at the end of follow-up was 95.8% in patients with only lymph node metastases and 76.0% in those with distant metastases. Tumor-related deaths were 3.6% and 23.7%, respectively. Our data indicate that 131I therapy is highly effective in the treatment of lymph node metastases from differentiated thyroid carcinoma.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
49.
A De Bellis A Bizzarro A Gattoni C Romano S Di Martino AA Sinisi S Abbadessa A Bellastella 《Canadian Metallurgical Quarterly》1995,80(7):2118-2121
Expression of intercellular adhesion molecule-1 (ICAM-1) and endothelial-leukocyte adhesion molecule-1 (ELAM-1) on endothelium can be considered a critical early step for leukocyte migration from blood to tissues during inflammatory processes. Increased circulating soluble ICAM-1 (sICAM-1) levels have been found in sera from patients with Graves' disease (GD) with or without ophthalmopathy. Serum soluble ELAM-1 (sELAM-1) levels have not been measured in these patients. The aim of this study was to clarify the behavior of sICAM-1 and sELAM-1 levels in patients with hyperthyroidism due to GD with or with or without ophthalmopathy and in hyperthyroid patients with toxic thyroid adenoma. We studied sICAM-1 and sELAM-1 levels in 130 subjects (age 23-54 yr), grouped as follows: group 1, 30 untreated hyperthyroid GD patients (21 females and 9 males) with active ophthalmopathy; group 2, 26 euthyroid GD patients (16 females and 10 males) with active ophthalmopathy; group 3, 33 hyperthyroid GD patients (22 females and 11 males) without ophthalmopathy; group 4, 11 untreated hyperthyroid patients (7 females and 4 males) with single toxic adenoma; and a control group of 30 healthy subjects (21 females and 9 males). sICAM-1 and sELAM-1 concentrations were measured by a sandwich enzyme linked immunosorbent assay (ELISA) method. Groups 1, 2, and 3 (P < 0.001 for all 3 groups) but not group 4 showed increased sICAM-1 levels compared with the control group. However, groups 1 and 2 (P < 0.001 for both) showed higher values of sICAM-1 than group 3, and group 1 showed higher sICAM-1 levels than group 2 (P < 0.002). Groups 1 and 2 (P < 0.001 for both) but not groups 3 and 4 showed sELAM-1 levels significantly higher than the control group and positively correlated to the severity score of Graves' ophthalmopathy (GO) (P < 0.002 for group 1 and < 0.01 for group 2). Our results confirm that increased sICAM levels in GD patients with or without ophthalmopathy (with higher levels in patients with GO) but not in hyperthyroid nonautoimmune patients may be the consequence of orbital and thyroid inflammation, and they also suggest that sICAM concentrations could reflect the degree of inflammatory activity. Increased sELAM-1 concentrations only, in patients with ophthalmopathy with or without hyperthyroidism significantly correlated to severity score of GO, suggest the measurement of sELAM-1 levels as a specific marker of endothelium activation in GO. 相似文献
50.
A new continuous-flow recycle microwave reactor for homogeneous and heterogeneous chemical reactions
A new continuous-flow recycle microwave reactor suitable for organic synthesis has been developed to handle 0.51 quantities of reagents. The apparatus, which is designed for laboratory use, operates at atmospheric pressure in open- or closed-loop mode. It is fitted with a temperature control system. We describe this novel reactor and illustrate its efficiency with examples of organic syntheses carried out using both homogeneous and heterogeneous reactions. 相似文献