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11.
Diabetic muscle infarction (DMI) is a rare complication of diabetes mellitus. We report the first recorded case in Japan. A 45-year-old Japanese woman presented with severe pain in the left antero-medial thigh. She had a 14-year history of Type 2 diabetes mellitus (DM). She had first noticed pain in her left thigh after a walk 2 weeks prior to presentation. The pain worsened progressively. She noticed a firm mass in her left thigh. T2-weighted magnetic resonance imaging (MRI) demonstrated a high-intensity signal in the muscle bulk of the anterior component of the left thigh. A needle biopsy of the mass showed necrosis. She was treated with bedrest and an antiplatelet agent. The mass disappeared 8 weeks after admission. DMI is a rare complication of poorly controlled diabetes mellitus. Twenty-seven cases with DMI have been reported in the English literature but we believe this is the first Japanese case with DMI.  相似文献   
12.
Mechanical properties of semi‐interpenetrating polymer network (semi‐IPN) elastomers consisting of chemical networks and self‐associative/non‐associative guest chains are demonstrated. Amorphous low Tg polyesters with thiol side groups (PE‐SH) are first synthesized by melt polycondensation. PE‐SH are then converted to polyesters containing COOH side groups (PE‐COOH) and amide side groups (PE‐amide) through Michael addition reaction of thiol groups with acrylic acid and acrylamide, respectively. Homogeneous semi‐IPN elastomers are obtained by thermal cross‐linking for bulk mixtures of PE‐COOH and PE‐amide in the presence of diepoxy cross‐linkers, where COOH and epoxy groups are reacted to form chemical cross‐links while the amide units form self‐complementary hydrogen bonds. Another sample containing non‐associative chains is also prepared by using polyester with N,N‐dimethylamide units, instead of PE‐amide. Dynamic mechanical analysis reveals that guest chain incorporation systematically brings plateau modulus reduction and a unique relaxation with higher tan δ value depending on the fraction and nature of guest chains. Tensile properties are also affected by the fraction and nature of guest chains; the incorporation of hydrogen bonded chains are beneficial to enhance breaking elongation and toughness without the sacrifice of maximum stress. The knowledge found in this work will be thus beneficial for creating tough soft materials with damping applications.  相似文献   
13.
Chlorine and oxygen evolving at RuO2/Ti and RuO2–TiO2/Ti anodes have been simultaneously determined at electrode potentials from 1.0 to about 2V (vs Ag/AgCl) by differential electrochemical mass spectroscopy (DEMS). On the RuO2/Ti anodes, the threshold electrode potential for oxygen evolution increased with a decrease in RuO2 loading, while the chlorine evolution potential was unchanged. Low RuO2 loading anodes gave a high chlorine evolution ratio under various constant electrolysis potentials. On the RuO2–TiO2/Ti anodes, the threshold electrode potential for oxygen evolution increased with an increase in the TiO2 content more remarkably than that for chlorine evolution. High TiO2 content anodes gave a high chlorine evolution ratio at various constant electrolysis potentials. The combination of RuO2 and TiO2 exhibits a remarkable effect with respect to the enhancement of chlorine evolution selectivity.  相似文献   
14.
The flux of the CaO‐Al203‐BaO‐CeO2‐MgO system as a desulphurization flux containing no fluorine for the secondary metallurgy process was evaluated in this study. The flux composition was designed using the eutectic compositions of the binary systems. The melting and desulphurization abilities of the fluxes were evaluated by measuring their liquidus temperatures and the distribution ratios of sulphur between the fluxes and the carbon‐saturated iron or stainless steel. The lowest liquidus temperature of 1325°C was obtained by adding 5.7 mass% MgO to the 80mass%A‐20mass%B flux. (A: 12CaO‐7Al2O3, B: BaCeO3+12mass%Al2O3). The distribution ratios of sulphur and sulphide capacities of the fluxes in this study were higher than those of the commercial product of calcium aluminate flux. This means that the CaO‐Al2O3‐BaO‐CeO2‐MgO fluxes developed in this study have higher desulphurization and melting abilities compared with the commercial product of calcium aluminate flux.  相似文献   
15.
Ruthenium-oxide nanosheet (RuO2ns) crystallites with thickness less than 1 nm were prepared via chemical exfoliation of a layered potassium ruthenate and deposited onto carbon supported platinum (Pt/C) as a potential co-catalyst for fuel cell anode catalysts. The electrocatalytic activity towards carbon monoxide and methanol oxidation was studied at various temperatures for different RuO2ns loadings. An increase in electrocatalytic activity was evidenced at temperatures above 40 °C, while little enhancement in activity was observed at room temperature. The RuO2ns modified Pt/C catalyst with composition of RuO2:Pt = 0.5:1 (molar ratio) exhibited the highest methanol oxidation activity. CO-stripping voltammetry revealed that RuO2ns promotes oxidation of adsorbed CO on Pt. In addition to the enhanced initial activity, the RuO2ns modified Pt/C catalyst exhibited improved stability compared to pristine Pt/C against consecutive potential cycling tests.  相似文献   
16.
Rutile-type Ru1−xVxO2 nanoparticles possessing high surface area were prepared by a polymerizable-complex method and its electrochemical supercapacitor behavior was studied. X-ray diffractometry, energy-dispersive X-ray analysis, and N2 adsorption/desorption measurements were used to characterize the structure of the products. The electrochemical supercapacitor behavior of thick and thin films was studied by cyclic voltammetry in various acidic, neutral, and alkaline electrolytes. Ru1−xVxO2 exhibited extremely enhanced supercapacitive properties compared to pure RuO2. The highest surface redox activity was achieved with an acidic electrolyte. Ru1−xVxO2 showed negligible surface redox activity in neutral electrolytes.  相似文献   
17.
Six to eight months after the Tokyo subway attack in March 1995, the neurophysiological effects of acute sarin poisoning were investigated in 18 passengers exposed to sarin (sarin cases) in the subways to ascertain the focal or functional brain deficits induced by sarin. The event-related and visual evoked potentials (P300 and VEP), brainstem auditory evoked potential, and electrocardiographic R-R interval variability (CVRR), together with the score on the posttraumatic stress disorder (PTSD) checklist, were measured in the sarin cases and the same number of control subjects matched for sex and age. None of the sarin cases had any obvious clinical abnormalities at the time of testing. The P300 and VEP (P100) latencies in the sarin cases were significantly prolonged compared with the matched controls. In the sarin cases, the CVRR was significantly related to serum cholinesterase (ChE) levels determined immediately after exposure; the PTSD score was not significantly associated with any neurophysiological data despite the high PTSD score in the sarin cases. These findings suggest that asymptomatic sequelae to sarin exposure, rather than PTSD, persist in the higher and visual nervous systems beyond the turnover period of ChE; sarin may have neurotoxic actions in addition to the inhibitory action on brain ChE.  相似文献   
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19.
Here we present a case of variant GSS disease with mutations in codons 1055 and 129 in a prion protein. The patient was a 54-year-old male, who developed weakness in the lower limbs and spastic, wide-based gait at the age of 46 years. Subsequently he developed dementia and spastic quadriplegia at the age of 49. He had marked pseudobulbar palsy at the age of 50 and became bed-ridden in decorticated posture at teh age of 53. CT and MRI examinations revealed marked atrophy of the frontal and temporal lobes, but the occipital lobes and the cerebellum were spared. His sister had been reported by Amano, et al. in 1992 as a case of variant GSS syndrome, who had very similar clinical features, and had numerous prion protein positive plaques in her cerebral cortex at the time of autopsy. His sister was confirmed to have the same mutations in a prion protein as the present case in later genetic studies.  相似文献   
20.
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