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11.
This study was conducted as a first step in order to obtain green materials for food packaging by using an eco‐friendly bioplastic, polylactic acid (PLA), and nontoxic plasticizers. Different types of nontoxic biocompatible plasticizers/lubricants, both obtained in the laboratory, as well as commercial ones, were employed to modulate physical and mechanical properties of PLA. Melt compounding by means of a Brabender mixer led to obtaining of homogeneous materials. The incorporation of PLA oligomer, l ‐lactide, poly(ethylene glycol), and epoxidized soybean oil (USE) improved the melt flow and processability, increasing the hydrophilicity of the resulted plasticized PLA systems. USE significantly increased the elongation at break, reduced the glass transition temperature, and increased the PLA chain mobility. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43223.  相似文献   
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The electric field gradients at 199mHg nuclei have been measured via the perturbed angular correlation (PAC) technique, allowing a full characterization of the Hg neighborhood charge distribution at high oxygen doping on the Hg planes. The PAC technique has been applied to investigate the effect of high oxygen pressure during the measurement. Polycrystalline HgBa2CaCu2O6+δ (Hg-1212) samples have been annealed at 152 bar pressurized oxygen. The influence of oxygen pressure during the experiment was then investigated by measuring the samples at atmospheric pressure and under 152 bar oxygen pressure.  相似文献   
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Novel physically cross-linked cryogels containing polyvinyl alcohol (PVA) and various amounts of microcrystalline cellulose were obtained by freezing/thawing technique. The main goal of this study was to improve the properties and the performances of the pure PVA cryogels. The morphological aspects of the cryogels were studied by scanning electron microscopy (SEM). The Fourier transform infrared spectroscopy (FT-IR) was used to reveal the presence of the interactions between the two polymers. Changes in crystallinity of the samples were confirmed by X-ray diffraction (XRD) and by FT-IR spectroscopy. The modification of the thermal behavior induced by cellulose was studied by thermogravimetry. Rheological analysis revealed higher values of storage modulus (G′) for the cryogels containing higher amounts of cellulose. The degree and rate of swelling were controlled by the presence of the natural polymer in the network. The potential application as bioactive compound carriers was tested, using vanillin as an active agent.  相似文献   
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BACKGROUND: Segmental neurofibromatosis (NF V) is ten times less frequent than Recklinghausen disease. Would the risk of visceral involvement in this uncommon form of neurofibromatosis warrant systematic imaging procedures? CASE REPORT: A 31-year-old man consulted for a voluminous plexiform neurofibroma in the left lumbar area. More ventrally, on the left side, there was also a café au lait spot. There were no Lisch nodules. The chest and abdominopelvic computed tomography and magnetic resonance imaging showed intramuscular tumoral extension, two neurofibromas in the 9th intercostal space and a voluminous 5-cm tumor situated in the left adrenal area. After resection pathology examination of the surgical specimen confirmed the diagnosis of ganglioneuroma. DISCUSSION: In this patient, all the neurofibromas and the café of lait spot developed in the territories of the left T10 and adjacent spinal roots. This was also true for the ganglioneuroma which developed on the deep sympathetic ramus to the adrenal gland which originates essentially from roots T8 to T11. This would place this case in the second subgroup of NF V in Roth's classification. Only six other cases have been reported in the literature. Such deep localizations are very likely to be underestimated, raising the problem of their detection and the correct protocol to follow asymptomatic forms, especially to detect disease progression to malignant degeneration which has a poor prognosis. Patients with a NF V should receive genetic counselling with a search for a family history, other signs of neurofibromatosis and Lisch nodules. In young patients, the risk of deep asymptomatic spread underlines the importance of regional computed tomographic or magnetic resonance explorations.  相似文献   
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BACKGROUND: The selective proteinuria observed in patients with focal segmental glomerulosclerosis (FSGS) suggests an abnormal loss of fixed anionic charges on the glomerular capillary wall. METHODS: In this article, we have studied the putative presence of such factor(s) by using a new in vitro assay to assess glomerular permselectivity by measuring glomerular volume variation (GVV) in isolated glomeruli after hypotonic stress. We randomly tested the serum GVV activity of 10 healthy donors and 143 patients before transplantation. Of the patients, 80 had FSGS, 26 membranous glomerulonephritis, 19 polycystic kidney disease, and 18 malformative uropathies. Moreover, we tested the pre- and posttransplantation serum of 14 patients with recurrence and 14 without recurrence. RESULTS: Serum GVV was significantly higher in patients with FSGS than in those with the other end-stage renal diseases studied (P<0.01) or in healthy donors (P<0.01). However, a wide distribution of serum GVV activity in patients with and without FSGS was observed. Statistically, pregraft GVV values were not predictive of the recurrence of FSGS after transplantation. Moreover, we observed a significant decrease in serum GVV activity after transplantation in patients without recurrence (P<0.01) compared to those who underwent a recurrence. CONCLUSIONS: These results reinforce the hypothesis of a circulating factor that alters glomerular albumin permselectivity in FSGS patients. However, the presence of this factor before transplantation did not appear to predict relapse of the disease after transplantation, as recently supported, although its activity seems to be down-regulated after transplantation in patients who do not experience recurrence of the disease.  相似文献   
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Current directions in autism spectrum disorder (ASD) research may require moving beyond genetic analysis alone, based on the complexity of the disorder, heterogeneity and convergence of genetic alterations at the cellular/functional level. Mass spectrometry (MS) has been increasingly used to study CNS disorders, including ASDs. Proteomic research using MS is directed at understanding endogenous protein changes that occur in ASD. This review focuses on how MS has been used to study ASDs, with particular focus on proteomic analysis. Other neurodevelopmental disorders have been investigated using MS, including fragile X syndrome (FXS) and Smith-Lemli-Opitz Syndrome (SLOS), genetic syndromes highly associated with ASD comorbidity.  相似文献   
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Patients suffering from end‐stage renal disease experience multiple disabilities, such as muscle wasting, weakness, higher postural sway, and fall rates compared with healthy population, which has a negative effect on physical functioning and autonomy. The vital treatment of hemodialysis is recognized to induce important post‐hemodialysis fatigue, hypotension, cramps, and headache due to the rapid fluid redistribution, among others. Nevertheless, even the well‐known negative effect of aforementioned consequences of hemodialysis treatment, its effect on physical function, especially postural balance, is unclear. Thus, this study hypothesized the adverse effect of hemodialysis treatment on postural sway in 12 end‐stage renal disease patients (mean age 63.3 ± 11 years) through the analysis of center‐of‐pressure (COP) trajectories recorded before and immediately after hemodialysis session. Evident postural alterations were observed at post‐hemodialysis balance assessment for COP position‐based (Fs < 7.7, P < 0.02) and COP velocity‐based variables (Fs > 2.33, P < 0.05), without changes in complexity of COP time series in anteroposterior and mediolateral directions. These results suggest that period after hemodialysis treatment is particularly unsafe, as evidenced by important disability in postural control, and highlight the importance of the medical support and falls‐related prevention strategies of these older frail patients after hemodialysis treatment.  相似文献   
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