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161.
The thermomagnetization curves and the hyteresis loops of the amorphous alloy Fe92Zr8 at low temperature have been investigated. Spin-glass-like behavior such as a thermomagnetic history and relaxation of remanence has been observed. 相似文献
162.
Oguri H Maeda N Izumiya C Kusume T Yamamoto Y Fukaya T 《Magnetic resonance imaging》2004,22(9):1333-1337
The incidence of cervical adenocarcinoma is increasing. Nabothian cysts are a common gynecologic condition; if multiple and/or large cysts are present, it is difficult to differentiate them from a minimal-deviation adenocarcinoma (MDA), which is classified as a special type of cervical adenocarcinoma. We report three cases of deep nabothian cysts and three cases of MDAs. Magnetic resonance imaging (MRI) findings, signs, and symptoms of these cases are described. The absence of a watery discharge and an MR image displaying a round or oval cyst without enhancement after intravenous gadolinium are helpful in the diagnosis of a deep nabothian cyst. 相似文献
163.
Photodynamic Diagnosis Using 5‐Aminolevulinic Acid in 41 Biopsies for Primary Central Nervous System Lymphoma 下载免费PDF全文
Tetsuya Yamamoto Eiichi Ishikawa Shunichiro Miki Noriaki Sakamoto Alexander Zaboronok Masahide Matsuda Hiroyoshi Akutsu Kei Nakai Wataro Tsuruta Akira Matsumura 《Photochemistry and photobiology》2015,91(6):1452-1457
We evaluated the feasibility of 5‐aminolevulinic acid (5‐ALA)‐mediated photodynamic diagnosis (PDD) in the biopsy for primary central nervous system lymphoma (PCNSL). 5‐ALA (20 mg kg?1) was administered orally 4 hours preoperatively. Forty‐one biopsies obtained under PDD in 47 consecutive biopsies (46 patients) that were finally pathologically diagnosed as PCNSL were evaluated. Positive fluorescence was observed in 34 of those 41 biopsies (82.9%). An intraoperative pathological diagnosis (IOD) of suspected PCNSL was made in 21 of the biopsies with positive fluorescence (61.8%). However, the eight IODs in the remaining 13 biopsies (23.5%) were not correct (atypical cell, 4; high‐grade glioma, 1; gliosis, 1; unremarkable, 2). In those 8 biopsies, PCNSL was confirmed by the final pathological diagnosis. There was no difference in the mean Mib‐1 labeling index between the biopsies with positive fluorescence (86.5%) and those without positive fluorescence (90.0%). IOD was not performed in 6 biopsies; however, 5 of those biopsies (83.3%) showed positive fluorescence and were finally pathologically diagnosed as PCNSL. Use of PDD in biopsies for patients with suspected PCNSL is a reliable way of obtaining specimens of adequate quality for the final pathological diagnosis and may lead to improved diagnostic yield in the biopsy of PCNSL. 相似文献
164.
Chitoshi Kitamura Yusuke Tanigawa Takashi Kobayashi Hiroyoshi Naito Hiroyuki Kurata Takeshi Kawase 《Tetrahedron》2012,68(6):1688-1694
Six 17,17-dialkyltetrabenzo[a,c,g,i]fluorenes (dialkylTBFs) 2–7 (methyl to n-hexyl) were prepared by treatment of 17H-tetrabenzo[a,c,g,i]fluorene (TBF) 1 with n-alkyl halides under basic conditions in moderate yields upon column chromatography and recrystallization. All the compounds show intense blue fluorescence in solutions. On the other hand, in the solid state, the fluorescent spectra and the quantum yields (Φp) vary with their alkyl chains. In particular, the Φp values of 4–7 bearing n-propyl to n-hexyl groups are close to unity, while the fluorescence of 1 is almost quenched. Crystallographic analyses of 2–7 revealed that the TBF moieties have helicene-like chiral structures in the crystals, and that the alkyl groups basically take an all-trans planar conformation. Because the longer alkyl substituents can serve as a spacer to prevent TBF nuclei from aggregation, π–π interactions of the TBF moieties probably play an important role in quenching the solid-state fluorescence. The relationship between the optical properties and molecular arrangements in the crystals are discussed. 相似文献
165.
Saito T Wu CC Shiku H Yasukawa T Yokoo M Ito-Sasaki T Abe H Hoshi H Matsue T 《The Analyst》2006,131(9):1006-1011
A quantitative analysis of the oxygen concentration profile near a poly(dimethylsiloxane) (PDMS) microfluidic device was performed using scanning electrochemical microscopy (SECM). A microchannel filled with sodium sulfite (Na(2)SO(3)) aqueous solution was imaged by SECM, showing that the oxygen diffusion layer of the PDMS microchannel was observed to be hemicylindrical. Based on a theoretical analysis of the hemicylindrical diffusion layer of the microchannel, the total oxygen mass transfer rates of oxygen to the PDMS microchannel filled with the Na(2)SO(3) solution was calculated to be (4.01 +/- 0.30) x 10(-12) mol s(-1). This is the maximum value of the oxygen transfer rate for this PDMS microchannel device. The oxygen consumption rate increased almost linearly with the logarithm of the concentration of E. coli cells (10(6) approximately 10(8) cells). The respiratory activity for a single E. coli cell was estimated to be approximately 4.31 x 10(-20) mol s(-1) cell(-1). 相似文献
166.
Simple method yielding new emission peaks to the X-ray phosphor and its mechanism were investigated using concentrated-dye-molecule-doped silica nanoparticles (dye-silica nanoparticles) and X-ray phosphors. The dye-silica nanoparticles were coated on the sheet of the X-ray phosphor using 20 wt% polyvinyl alcohol solution. The fluorescence of the dye-silica nanoparticle coated onto X-ray phosphor was successfully observed by X-ray irradiation. The fluorescent cascade from the X-ray-irradiated phosphor could be used in the excitation of the dye-silica nanoparticles by coating on the calcium tungstate (X-ray phosphor). The observed new fluorescence was based on the extent of the overlapping of wavelengths between the emission of the X-ray phosphor and the excitation of the dye-silica nanoparticles. The fluorescent peak of the calcium tungstate as the X-ray phosphor shifted from 434 to 425 nm. The dye-silica particle-calcium tungstate hybrid material showed new emission peaks from 543 to 601 nm due to the addition of fluorescein, rhodamine red-X, or cy5. The new emission peaks changed by the content of dye and the size of the silica nanoparticles. The fluorescence intensity ratio of the new fluorescence peaks at 543 nm against that of the X-ray phosphor depended on the fluorescent cascade from the X-ray-irradiated X-ray phosphor. It can closely match the overall emission of the phosphorous intensity screens to the sensitivity of the film allowing lower dose X-rays to obtain the same image clarity. 相似文献
167.
We study the effect of disorder on the intrinsic anomalous Hall conductivity in a magnetic two-dimensional electron gas with a Rashba-type spin-orbit interaction. We find that anomalous Hall conductivity vanishes unless the lifetime is spin-dependent, similar to the spin Hall conductivity in the nonmagnetic system. In addition, we find that the spin Hall conductivity does not vanish in the presence of magnetic scatterers. 相似文献
168.
In this article novel sulfonated block copolyimides with various diamine compositions and block chain lengths were synthesized by chemical imidization using a two‐pot procedure. The proton conductivities of the block copolyimide membranes were measured as functions of the relative humidity and temperature using four‐point‐probe electrochemical impedance spectroscopy. The proton conductivity of the membranes strongly depended on the block chain lengths and increased with an increase in the block chain lengths. The proton conductivity of NTDA‐BDSA‐b‐6FAP (112/48) as the block copolyimide membrane was approximately 0.35 S cm−1 which indicated a higher value when compared to that determined for Nafion®. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
169.
The total synthesis of mycestericin A (1) and its 14-epimer 34 is described herein. The Overman rearrangement of an allylic trichloroacetimidate derived from l-tartrate generated a tetra-substituted carbon with nitrogen and subsequent stereoselective transformations afforded the highly functionalized left-half segment, vinyl iodide. Cross-coupling of the vinyl iodide with a chiral organometallic species synthesized from d-tartrate under the Negishi or Suzuki-Miyaura coupling conditions, followed by deprotection, completed the total synthesis of 1. The 14-epimer of mycestericin A was also synthesized, and a comparison of [α]D values of peracetyl γ-lactone derivatives of mycestericin A and its 14-epimer as well as degradation studies of 1 and 34 fully confirmed the proposed absolute structure of mycestericin A. 相似文献
170.
Three new pyrazine-bridged dimers of oxoacetatotriruthenium with an NO ligand are synthesized. These complexes show two types of stable mixed-valence states. The ν(NO) stretches for five oxidation states were obtained, and the intramolecular electron-transfer rate within the mixed-valence state is evaluated from the IR spectral line-shape simulation based on Bloch-type analysis, which is the first application of this method to a spectator ligand of NO. 相似文献