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A case of osteofibrodysplasia of the long bones in a 4-year-old girl is reported with ipsilateral tibial and fibular involvement. The radiological pattern of the lesions suggested fibrodysplasia but not their MRI signal characteristics. This diagnostic imaging mismatch and the bifocality of the lesion were the tell-tale indications for the confirmatory bone biopsy yielding osteofibrous dysplasia of Campanacci. 相似文献
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Bulk superconducting samples of type Tl0.5Pb0.5Sr1.6Ba0.4CaCu2−x
Ru
x
O7−δ, (Tl, Pb)/Sr-1212, with 0.0 ≤ x ≤ 0.525 were prepared by the conventional one-step solid-state reaction technique. The prepared samples were investigated
using X-ray powder diffraction, electrical resistivity and electron paramagnetic resonance (EPR) measurements. Enhancement
of the phase formation, superconducting transition temperature T
c and hole carriers concentration P was observed up to x = 0.075. For x > 0.075, a reverse trend was observed. EPR spectra were measured at different temperatures (120–290 K) for all prepared samples.
The number of spins N participating in the resonance and the paramagnetic susceptibility χ were calculated as a function of both Ru-content and
temperature. N and χ increased as the Ru-content increased. A linear relationship between logN and 1/T was established, from which the activation energy E
a was calculated as a function of the Ru-content. The temperature dependence of χ was fitted according to Curie–Weiss type
of magnetic behavior. Curie constant C, Curie temperature θ, the effective magnetic moment μ and the electronic specific heat γ were estimated as a function of the Ru-content. 相似文献
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ABSTRACTBayfol (PC-PBT blend ?lm) is a class of polymeric solid-state nuclear track detector which has a lot of applications in several radiation detection ?elds. It is a bisphenol-A polycarbonate PC blended with polybutylene terephthalate PBT. Bayfol/Palladium (PC-PBT/Pd) nanocomposite films have been deposited using the molding technique. It is worth mentioning that this report is almost the first one dealing with the topic of the changes of physical properties of Bayfol/Pd nanocomposite due to laser exposure. Samples from PC-PBT/Pd (5?wt%) nanocomposite were exposed to IR-pulsed laser of 5-W power, capable of producing 2000 pulses per second with pulse duration of 200?ns at 904?nm. The laser fluences were in the range 2–25?J/cm2. The resultant modi?cations in the exposed nanocomposite samples have been studied as a function of fluence using different characterization techniques such as X-ray diffraction (XRD), UV spectroscopy and color difference studies. The results indicate the proper dispersion of Pd nanoparticles in the PC-PBT matrix that causes a strong intermolecular interaction between Pd and PC-PBT, resulted in an increase in refractive index and the amorphous phase. Also, it is found that the laser exposure reduces the optical energy gap that could be attributed to the increase in structural disorder of the exposed PC-PBT/Pd nanocomposites due to crosslinking. Further, the color intensity ΔE, which is the color difference between the exposed samples and the non-exposed one, was increased with increasing the laser fluence, convoyed by a significant increase in the green and yellow color components. 相似文献
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羧甲基纤维素钠水凝胶的制备及其生物降解性研究 总被引:9,自引:0,他引:9
用羧甲基纤维素钠(CMC—Na)制得了含水量高达98%的水凝胶,考察了防腐剂、交联剂、无机态氮素、有机态氮素、碳水化合物的加入量以及环境中pH值等因素对生物降解性的影响。结果表明:制备条件不同,水凝胶的生物降解性不同;环境中一定量铵根离子的存在有利于水凝胶的生物降解;在pH=5.2的环境中纤维素酶活性最高,降解程度最大。 相似文献
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Salah E. M. Eltom Ahmed A. H. Abdellatif Hamzah Maswadeh Mohsen S. Al-Omar Atef A. Abdel-Hafez Hamdoon A. Mohammed Eiman ME. Agabein Ibrahim Alqasoomi Salem A. Alrashidi Mohammed S. M. Sajid Mugahid A. Mobark 《Molecules (Basel, Switzerland)》2021,26(12)
The ostrich oil of Struthio camelus (Ratite) found uses in folk medicine as an anti-inflammatory in eczema and contact dermatitis. The anti-inflammatory effect of a γ-lactone (5-hexyl-3H-furan-2-one) isolated from ostrich oil and its formulated nano-emulsion in formalin-induced paw edema was investigated in this study. Ostrich oil was saponified using a standard procedure; the aqueous residue was fractionated, purified, and characterized as γ-lactone (5-hexyl-3H-furan-2-one) through the interpretation of IR, NMR, and MS analyses. The γ-lactone was formulated as nano-emulsion using methylcellulose (MC) for oral solubilized form. The γ-lactone methylcellulose nanoparticles (γ-lactone-MC-NPs) were characterized for their size, shape, and encapsulation efficiency with a uniform size of 300 nm and 59.9% drug content. The γ-lactone was applied topically, while the formulated nanoparticles (NPs) were administered orally to rats. A non-steroidal anti-inflammatory drug (diclofenac gel) was used as a reference drug for topical use and ibuprofen suspension for oral administration. Edema was measured using the plethysmograph method. Both γ-lactone and γ-lactone-MC-NPs showed reduction of formalin-induced paw edema in rats and proved to be better than the reference drugs; diclofenac gel and ibuprofen emulsion. Histological examination of the skin tissue revealed increased skin thickness with subepidermal edema and mixed inflammatory cellular infiltration, which were significantly reduced by the γ-lactone compared to the positive control (p-value = 0.00013). Diuretic and toxicity studies of oral γ-lactone-MC-NPs were performed. No diuretic activity was observed. However, lethargy, drowsiness, and refusal to feeding observed may limit its oral administration. 相似文献
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Nagaraja TN Nagesh V Ewing JR Whitton PA Fenstermacher JD Knight RA 《Magnetic resonance imaging》2007,25(3):311-318
A rat model of transient suture occlusion of one middle cerebral artery (MCA) was used to create a unilateral reperfused cerebral ischemic infarct with blood-brain barrier (BBB) opening. Opening of the BBB was visualized and quantitated by magnetic resonance (MR) contrast enhancement with a Look-Locker T(1)-weighted sequence either following an intravenous bolus injection (n=7) or during a step-down infusion (n=7) of gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA). Blood levels of Gd-DTPA after either input were monitored via changes in sagittal sinus relaxation rate. Blood-to-brain influx constants (K(i)) were calculated by Patlak plots. On the basis of the MRI parameters and lesion size, the ischemic injury was determined to be similar in the two groups. The bolus injection input produced a sharp rise in blood levels of Gd-DTPA that declined quickly, whereas the step-down infusion led to a sharp rise that was maintained relatively constant for the period of imaging. Visual contrast enhancement and signal-to-noise (S/N) ratios were better with the step-down method (S/N=1.8) than with bolus injection (S/N=1.3). The K(i) values were not significantly different between the two groups (P>.05) and were around 0.005 ml/(g min). The major reason for the better imaging of BBB opening by the step-down infusion was the higher amounts of Gd-DTPA in plasma and tissue during most of the experimental period. These results suggest that step-down MR contrast agent (MRCA) administration schedule may be more advantageous for detection and delineation of acute BBB injury than the usually used bolus injections. 相似文献
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Mia A. Levy John B. Freymann Justin S. Kirby Andriy Fedorov Fiona M. Fennessy Steven A. Eschrich Anders E. Berglund David A. Fenstermacher Yongqiang Tan Xiaotao Guo Thomas L. Casavant Bartley J. Brown Terry A. Braun Andre Dekker Erik Roelofs James M. Mountz Fernando Boada Charles Laymon Matt Oborski Daniel L. Rubin 《Magnetic resonance imaging》2012