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Melt-electrospinning is an eco-friendly method for producing ultra-fine fibers without using any solvent. We prepared webs of poly(ethylene terephthalate) (PET) through melt-electrospinning using CO2 laser irradiation for heating. The PET webs comprised ultra-fine fibers of uniform diameter (average fiber diameter = 1.66 μm, coefficient of variation = 19%). The co-existence of fibers with high and low molecular orientation was confirmed through birefringence measurements. Although the level of high orientation corresponded to that of commercial highly oriented yarn, crystalline diffraction was not observed in the wide-angle X-ray diffraction (WAXD) analysis of the webs. The crystallinity of the webs was estimated using differential scanning calorimetry (DSC). The fibers with higher birefringence did not exhibit any cold crystallization peak. After annealing the web at 116 °C for 5 min, a further increase in the birefringence of the fibers with higher orientation was observed. The WAXD results revealed that the annealed webs showed crystalline diffraction peaks with the orientation of the c-axis along the fiber axis. In summary, the formation of fibers with a unique non-crystalline structure with extremely high orientation was confirmed.  相似文献   
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Documenta Ophthalmologica - Owing to several factors, peak latencies of pattern-reversal visual evoked potentials (p-VEP) are delayed when viewing liquid crystal display (LCD) monitors compared to...  相似文献   
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Background: Influenza-associated encephalopathy (IE) is a serious complication during influenza viral infection. Common clinical symptoms of IE include seizures and progressive coma with high-grade fever. We previously reported that hypercytokinemia and monocyte/macrophage activation may play an important role in the pathogenesis of IE. CD163 is a scavenger receptor for hemoglobin–haptoglobin complexes and is expressed by monocytes/macrophages. Proteolytic cleavage of monocyte-bound CD163 by matrix metalloproteinases releases soluble CD163 (sCD163). However, there have been no reports regarding serum sCD163 levels in IE patients. Methods: We measured serum levels of sCD163 as a marker of monocyte/macrophage activation in IE patients with poor outcomes, those without neurological sequelae, influenza patients without IE, and control subjects. Results: Serum sCD163 levels were significantly higher in IE patients with poor outcomes than in those without neurological sequelae. In particular, sCD163 levels in cases of death were significantly higher than those in other cases. Conclusions: Our results suggest that monocyte/macrophage activation is related to the pathogenesis of severe IE.  相似文献   
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Lysophosphatidylcholine (LPC) is metabolized from a membrane phospholipid and modulates a variety of channels in the plasma membrane (PM). We examined LPC modulation of cardiac ryanodine receptor (RyR) channels in the sarcoplasmic reticulum (SR) using the planar lipid bilayer method to measure the single-channel currents. Micromolar concentrations of LPC increased the open probability of the reconstituted RyR channels irrespective of whether LPC was added to the cis or trans chamber. LPC also increased the membrane capacitance of the bilayer. The effects of LPC contrasted well with those of sphingosylphosphorylcholine (SPC). Taken together, these results suggest that amphipathic lipid LPC does not bind directly to the RyR channel protein, but rather, is incorporated into the bilayer membrane and activates the channel. Thus, we consider cell membrane-derived LPC to be a putative endogenous mediator that activates not only plasma membrane channels but also RyR channels and induces arrhythmogenic Ca2+ mobilization in cardiomyocytes.  相似文献   
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Lignans are widely distributed in plants and exhibit significant pharmacological effects, including anti-tumor and antioxidative activities. Here, we describe the total synthesis of schizandriside (1), a compound we previously isolated from Saraca asoca by monitoring antioxidative activity using the 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay. Starting from a tandem Michael-aldol reaction, the lignan skeleton was synthesized in 6 steps, including a cyclization step. To determine the stereochemistry of 1, we synthesized the natural product (±)-isolariciresinol (18) from alcohol 17. Comparison of the spectral data showed good agreement. Glycosylation was investigated using four different glycosyl donors. Only the Koenigs–Knorr condition using silver trifluoromethanesulfonate with 1,1,3,3-tetramethylurea provided the glycosylated product. Deprotection and purification using reverse-phase high-performance liquid chromatography gave schizandriside (1) and its diastereomer saracoside (2). Synthesized 1, 2 and 18 showed antioxidant activity with IC50?=?34.4, 28.8, 53.0 μM, respectively.  相似文献   
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Journal of Natural Medicines - A new amide, named dehydropropylpantothenamide (1), was obtained by a co-culture of Nocardia tenerifensis IFM 10554T in the presence of the mouse macrophage-like cell...  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - To assess spontaneous blinking and anomalous eyelid movements in patients with hemifacial spasm with an emphasis on interocular...  相似文献   
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