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961.
Inhibition of acyl coenzyme A: cholesterol acyltransferase by 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors 总被引:1,自引:0,他引:1
Relatively high concentrations of MK-733 (simvastatin) and MK-803 (lovastatin, mevinolin), which are 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, were found to inhibit acyl coenzyme A: cholesterol acyltransferase (ACAT) of rabbit intestinal microsomes with IC50's of 2.0 x 10(-5) and 3.6 x 10(-5) M, respectively. Dihydroxy acid forms of both MK-733 and MK-803 did not inhibit ACAT activity. A kinetic analysis using a Lineweaver-Burk plot indicated that MK-733 is a competitive inhibitor of ACAT, with a Ki value of 1.2 x 10(-5) M. 相似文献
962.
We have reported fundamental studies on the TSH immunoradiometric assay, using TSH RIABEAD II kit (Dainabot). The sensitivity of the assay was 0.03 mu IU/ml and its C.V. was 27.2%. Intra- and inter-assay C.V. were less than 5%. Dilution test and recovery test were good. Serum TSH level was 0.3-4.0 mu IU/ml in normal subjects, less than 0.03 mu IU/ml in untreated Graves' disease and subacute thyroiditis. Therefore, it was found that the clear difference exist in serum TSH levels between normal subjects and patients with untreated Graves' disease. There was a well correlation on the serum TSH levels between this method and TSH radioimmunoassay kit (Amerlex TSH, r = 0.983). Especially, the measurement of serum TSH levels, using immunoradiometric assay kit, was useful for the diagnosis of patients with Graves' disease. 相似文献
963.
G. Böttger P. Allenspach A. Dönni Y. Aoki H. Sato 《Zeitschrift für Physik B Condensed Matter》1997,104(2):195-198
The magnetic ordering of Er ions in Er2Ba4Cu7O15-δ (δ = 0:7 and δ = 0:08) has been studied by low temperature heat capacity measurements. The Néel temperature T N of Er2Ba4Cu7O15-δ is almost independent of the oxygen concentration (TN = 0:54K for δ = 0:08 and T N = 0:50K for δ = 0:7). While an anisotropic two-dimensional (2D) Ising model describes the experimental data very well for Er2Ba4Cu7O14:92, this model cannot be applied to the oxygen reduced sample Er2Ba4Cu7O14:3. By using a model consisting of 1D-Ising chains and of 2D-Ising clusters of Er3+ ions we could fit the specific heat data of Er2Ba4Cu7O14:3 accurately. Our measurements show clearly that with the reduction of the oxygen content the in-plane anisotropy of the magnetic exchange coupling increases. 相似文献
964.
965.
A bicyclic dipeptide derivative with fixed conformation simulating that of the two central amino acid residues in type II′ β-turn has been synthesized starting from L-glutamic acid and L-cysteine in short steps. 相似文献
966.
M. Sato 《等离子体物理论文集》1985,25(6):573-577
The Abel integral equation in plasma spectroscopy is numerically solved by applying the Bessel four-point interpolation formula of degree two. The method is mathematically tractable, simplifying the Bockasten method. Tests through numerical simulations show that the method is as accurate as more elaborate methods, such as Bockasten, Minerbo-Levy, Piessens, etc. 相似文献
967.
The extraction of Cu(II) with 1-phenyl-3-methyl-4-acyl-5-pyrazolone (HA), in different organic solvents has been studied. The extraction mechanism of Cu(II) and the composition of the extracted species has been determined. Cu(II) was extracted as CuA2, or in the presence of TOPO, as CuA2TOPO. The extraction constants do not change regularly with increasing the length of acyl chain in the 1-phenyl-3-methyl-4-acyl-5-pyrazolone derivatives. The effect of the temperature on the extraction of Cu(II) has also been investigated. 相似文献
968.
Hiroji Oda Mitsuyoshi Sato Yoshitomi Morizawa Koichiro Oshima Hitosi Nozaki 《Tetrahedron》1985,41(16):3257-3268
Dimethylphenylsilyl group is removed from a vinyl carbon with tetrabutylammonium fluoride. The presence of phenyl group on silicon atom plays a critical role. The cleavage of allyldimethylsilyl- and alkoxydimethylsilyl groups also proceeds very easily. 相似文献
969.
Summary Noise effects on phase lockings in a system consisting of a piecewise-linear van der Pol relaxation oscillator driven by a
periodic input are studied. The problem of finding the period of the oscillator is reduced to the first-passage-time problem
of the Ornstein-Uhlenbeck process with time-varying boundary. Using the probability density functions of the first-passage
time, the operator which governs a transition of an input phase density after one cycle of the oscillator is defined. Phase
lockings in a stochastic sense are investigated on the basis of the density evolution by the operator.
Paper presented at the International Workshop ?Fluctuations in Physics and Biology: Stochastic Resonance, Signal Processing
and Related Phenomena?, Elba, 5–10 June 1994. 相似文献
970.
E. Sato K. Ohtake R. Yamamoto M. Doyama T. Mori K. Soda S. Suga K. Endo 《Solid State Communications》1985,55(12):1049-1052
The vacuum ultraviolet photoemission spectra of quasi-one-dimensional charge density wave ( CDW ) system, (TaSe4)2I, were measured for photon energies between 32 and 100 eV at room temperature ( in the normal phase ) and at about 100 K ( in the CDW phase ). The spectrum of Ta 4f core-levels has shown no additional splitting due to the two different Ta sites. The spectra of the valence and conduction bands have revealed the resonant enhancement for the excitation of the Ta 5p core states, which demonstrates the remarkable hybridization of Ta 5d orbitals with Se 4p orbitals with binding energies smaller than 4 eV. In the CDW phase, the partial cross section decreases for both Ta 5d bands and Se 4p bands with Ta 5d components. 相似文献