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71.
72.
We investigated the microbial conversion of curcumin (1) using endophytic fungi associated with the rhizome of Curcuma longa (Zingiberaceae). We found that Diaporthe sp., an endophytic filamentous fungus, converts curcumin (1) into four colorless derivatives, namely (3R,5R)-tetrahydrocurcumin (2), a novel (3R,5S)-hexahydrocurcumin (3) named neohexahydrocurcumin, (3S,5S)-octahydrocurcumin (4) and meso-octahydrocurcumin (5).  相似文献   
73.
Essential oils have traditionally been used for decades to alleviate the symptoms of various mental problems. In terms of anxiolytic-like properties, lavender oil is probably the most commonly used and best-studied essential oil. Although there is compositional variance among the oils extracted from different origins, there have been few studies performed to date to investigate how these differences affect the expression of anxiolytic-like activity. This paper discusses the interspecies differences and contributions of the main constituents in the expression of anxiolytic-like effects upon inhalation, as assessed in mice by the elevated-plus maze test, by comparing the essential oils from six different species of Lavandula. The results showed qualitative and quantitative variations in the tested oils, which results in significant differences in their anxiolytic-like activities. Our findings also suggest that linalyl acetate (LA) works synergistically with linalool (LO) and that the presence of both LA and LO is essential for the whole oil to work as an inhaled anti-anxiety agent.  相似文献   
74.
ABSTRACT

High pressure hydrous phases with distorted rutile-type structure have attracted much interest as potential water reservoirs in the Earth’s mantle. An in-situ X-ray diffraction study of β-CrOOH was performed at high pressures of up to 6.2?GPa and high-temperatures of up to 700?K in order to clarify the temperature effect on compression behaviors of β-CrOOH. The P-V-T data fitted to a Birch–Murnaghan equation of state yielded the following results: isothermal bulk modulus KT0?=?191(4)?GPa, temperature derivative (?KT/?T)P?=??0.04(2)?GPa?K?1, and volumetric thermal expansion coefficient α?=?3.3(2)?×?10?5?K?1. In this study, at 300?K, the a-axis became less compressible at pressures above 1–2?GPa. We found that the pressure where the slopes of a/b and a/c ratios turned positive increased with temperature. This is the first experimental study indicating the temperature dependence of the change in the axial compressibility in distorted rutile-type M3+OOH.  相似文献   
75.
76.
A manifold is described which permits the analysis of less than 1 ml of sample solution. Water- and air-compensation methods for the introduction of the carrier stream into the nebulizer are effective in obtaining sensitive and reproducible measurements of magnesium, but air-compensation gives higher peak responses.  相似文献   
77.
78.
An apparatus and the procedure for cellulose acetate isoelectric focusing were refined and optimized for routine use in clinical laboratories. The space in the electrophoretic chamber was minimized to maintain high humidity during the run. The water content of the thin cellulose acetate membranes in the chamber was well controlled during isoelectric focusing and the effect of atmospheric carbon dioxide was also excluded. The temperature of the membranes was kept below 2 degrees C, even under conditions of high electric field strength for faster isoelectric focusing of high-molecular-weight proteins. No special training was required for technicians in clinical laboratories to obtain reproducible isoelectric profiles of human serum proteins.  相似文献   
79.
80.
We have measured spin correlation parameters that describe the elastic scattering of 800 MeV polarized protons from an L-type polarized deuteron target at laboratory angles below 20°. The measured parameters include the correlated analyzing powers ASL, ALL and ANLL and the proton spin-transfer coefficients C0L,S, C0L,L, CSL,N, CNL,S, CNL,L and CLL,N. The results are compared with single-scattering predictions based on different phase-shift solutions for the nucleon-nucleon scattering matrix.  相似文献   
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