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71.
Inside Back Cover: Stereodivergent Synthesis and Stereochemical Reassignment of the C79–C104 Fragment of Symbiodinolide (Chem. Eur. J. 6/2016) 下载免费PDF全文
72.
Electrosorption of some aromatic hydrocarbons on gold electrode has been studied by the measurement of the specular reflectivity change in 2-methoxyethanol containing about 0.2 M NaClO4. In the presence of the hydrocarbons, the reflectivity decrease was found to be enhanced in the positive side of the potential region, the decrease being ascribed to the taking place of adsorption. With the assumption that the reflectivity decrease is proportional to the coverage, the observed change was analysed by varying the concentrations of the hydrocarbon at varied potentials. The observed values could fairly be elucidated on the basis of the modified Langmuir isotherm in which the potential dependent term is included and the adsorption is assumed to proceed through the replacement of an adsorbed solvent molecule. Regarding a larger molecule, a larger number of solvent molecules was replaced and a larger negative value of the energy of adsorption was obtained. This is in accordance with the mechanism that the hydrocarbons are adsorbed by lying flat on the surface through the π-electron interaction. The rate of adsorption was examined at a lower concentration range and could be elucidated in terms of the diffusion controlled mechanism. Extension of the McIntyre-Aspnes theory to the multilayer system has been attempted and the net reflectivity change was shown to be the sum of the change due to each layer. The major cause of the reflectivity change was examined by comparing the observed wavelength dependence of the change with those calculated on the basis of the increase in the refractive index in the double layer or the electroreflectance. Both of the calculated curves were not in accordance with the observed curve, indicating that the other mechanism might play an important role. 相似文献
73.
The decomposition of α-diazoesters is notably catalyst-dependent; with rhodium (II) carboxylates a stereoselective insertion reaction leads to the title structures in high yield. 相似文献
74.
75.
Keisuke HIROTA Hiroo MATSUSE Shunji KOYA Ryuki HASHIDA Masafumi BEKKI Yoko YANAGA Kiyoko JOHZAKI Mami TOMINO Fumihiko MOURI Satoshi MORISHIGE Shuki OYA Yoshitaka YAMASAKI Koji NAGAFUJI Naoto SHIBA 《Physical Therapy Research》2021,24(1):69
Objective: Muscle atrophy is associated with autologous stem cell transplantation (ASCT)-related outcomes in patients with malignant lymphoma (ML). However, the impact of ASCT on muscle mass remains unclear in patients with ML. The aims of this study were to investigate changes in muscle mass and risk profiles for muscle atrophy after ASCT. Method: We enrolled 40 patients with refractory ML (age 58 [20-74] years, female/male 16/24, body mass index (BMI) 21.1 kg/m2 [17.1-29.6]). Psoas muscle mass was assessed using the psoas muscle index (PMI) before and after ASCT. Statistical analysis used: Independent factors associated with a severe decrease rate of change in PMI were evaluated by decision-tree analysis, respectively. Results: PMI was significantly decreased after ASCT (4.61 vs. 4.55 cm2/m2; P=0.0425). According to the decision-tree analysis, the regimen was selected as the initial split. The rates of change in PMI were −5.57% and −3.97% for patients administered MCEC and LEED, respectively. In patients who were administered LEED, the second branching factor was BMI. In patients with BMI < 20.3 kg/m2, the rate of change in PMI was −7.16%. On the other hand, the rate of change in PMI was 4.05% for patients with BMI ≥ 20.3 kg/m2. Conclusion: We demonstrated that muscle mass decreased after ASCT in patients with ML. Patients who received MCEC and patients with low BMI were at risk for a decrease in muscle mass. 相似文献
76.
Goshima S Kanematsu M Matsuo M Murakami T Hori M Takamura M Kondo H Kako N Moriyama N Nakamura H Hoshi H 《Magnetic resonance imaging》2004,22(3):379-388
The purpose of our study was to assess whether respiratory-triggered multishot fast spin echo (MS-FSE) and breath-hold half-Fourier single-shot fast spin echo (SS-FSE) images, in addition to breath-hold T(2)*-weighted gradient recalled echo (GRE) images, increase observer performance in the detection of malignant hepatic tumors with ferumoxide-enhanced magnetic resonance (MR) imaging. Ferumoxide-enhanced MR images obtained from 48 patients with 83 malignant hepatic tumors were retrospectively reviewed by three independent off-site readers. In the first image review, GRE images alone were reviewed. Then, MS-FSE images were added for the first combination review. Finally, SS-FSE images were added for the second combination review. Observer performances were tested by McNemar's test and receiver-operating-characteristic analysis for the clustered data. Sensitivity for hepatocellular carcinomas, metastases, and malignant hepatic tumors overall was significantly (p < 0.05) higher with GRE and MS-FSE combined and GRE, MS-FSE and SS-FSE combined than with GRE alone. For metastases, the Az value was significantly (p < 0.05) higher with GRE and MS-FSE combined, and GRE, MS-FSE and SS-FSE combined than with GRE alone. We confirmed the incremental value of ferumoxide-enhanced MR imaging by obtaining MS-FSE and SS-FSE images in addition to GRE images in the detection of malignant hepatic tumors. 相似文献
77.
The effects of fast neutron irradiation near 4.2°K on dilute Cu, Cu3Au, α-CuZn, β-CuZn and CuNi alloys were studied by electrical resistivity measurements. For Cu3Au, the recovery stage at ~ 100°K becomes more distinct with increasing long-range order, and is attributed to migration of interstitials. The ratio of the number of replacements to the number of displacements (C R /C F ) is estimated to be about 50 for neutron irradiation, in contrast to the previously reported value of ~2 for electron irradiation. For α-CuZn, a large recovery stage at ~150°K is found and attributed to annihilation of interstitids whose migration produces ordering. For β-CuZn, migration of interstitials also produces ordering. It is also suggested that in β-CuZn, the ratio C R /C F is larger for neutron irradiation than for electron irradiation as in the case of Cu3Au. The results on CuNi alloys are presented without explanation. 相似文献
78.
The structure, the energetics and the internal redox reactions of La0.7Sr0.3FexMn1−xO3 have been studied in the complete solid solution range 0.0<x<1.0. High temperature oxide melt drop solution calorimetry was performed to determine the enthalpies of formation from binary oxides and the enthalpy of mixing. There is a noticeable change in the energetics of the solid solution near x=0.7, which is due to the growing concentration of Fe4+ at higher Fe/(Fe+Mn) ratio. The balance between different valences of the transition metals, Mn and Fe, is the main factor in determining the energetics of the La0.70Sr0.30FexMn1−xO3 solid solution. 相似文献
79.
80.
A convergent synthesis of the A-E ring segment of ciguatoxin CTX3C was achieved via the intramolecular allylation of an α-chloroacetoxy ether and subsequent ring-closing metathesis. 相似文献