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1.
S. Homma-Takeda Y. Nishimura Y. Watanabe H. Imaseki M. Yukawa 《Journal of Radioanalytical and Nuclear Chemistry》2004,259(3):521-525
Stage-specific and age-dependent profiles of zinc, copper, manganese, and selenium in testis were examined in Wistar rats
by both inductively coupled argon plasma-mass spectrometry (ICP-MS) with a microdissection technique and in situ elemental
imaging of micro-PIXE analysis. The young adult animals (10 weeks old) contained higher levels of zinc and manganese in the
seminiferous tubules at stages VII-VIII than stages XI through VI and IX-X and the levels were higher than those of the immature
and old animals. Copper and selenium levels at stages VII-VIII of the young adult animals were also higher than those of the
immature and old animals. In stages VII and VIII, zinc was higher in the central area of the seminiferous epithelium, where
spermatozoa were localized, demonstrating a cell-specific property.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
2.
X.P. Zhu Tomiyuki Yukawa Hisayuki Suematsu Kiyoshi Yatsui Y. Inoue 《Applied Surface Science》2006,252(16):5776-5782
X-ray photoelectron spectroscopy (XPS) is used to probe oxidation states of Si species in particles deposited using a pulsed ion-beam evaporation method. The effects of He ambient gas, ion beam intensity and post-treatments on the oxides composition and oxygen content have been studied. It is found that presence of He ambient gas led to a profound oxidation of Si species as compared to that prepared in vacuum at the same ion-beam ablation energy, i.e. both increase of SiO2 component and oxygen concentration in the oxides coverage. The deposition in He also resulted in an increase of oxygen concentration even under lower ablation intensity, but a higher Si suboxides concentration. It is revealed that the reaction between Si and O was controlled by the ion beam intensity (temperature of Si plasma) and the gas ambient (collision probability of Si and O species). The difference in structure of oxide layers for samples obtained under various conditions is discussed based on the results of XPS analyses. 相似文献
3.
The mechanisms of nitrosation of acetone through sodium enolate [CH3CO1CH2]-Na+ (1) or naked enolate [CH3CO1CH2]- (2) with methyl nitrite CH3O3NO2 (3), and the reactivity of the syn-form of 3 (syn-3) during the C-N bond formation process were investigated using ab initio molecular orbital (MO) methods. Our results have demonstrated the predominant formation of E-1-hydroxyimino-2-oxo-propane CH3COCH=NOH (4E) when the complex [CH3CO1CH2NO2(O3CH3)]-Na+ was produced kinetically via a metal-chelated pericyclic transition state (TS(CHELATED)), in which the O3 atom of syn-3 was coordinated to the Na+ atom of 1. 相似文献
4.
Yasuhide Yukawa Hisao Morisaki Kiyoshi Tsuji Seung-Geon Kim Takashi Ando 《Tetrahedron letters》1981,22(51):5187-5190
The behavior of ion pairs in the trifluoroacetolysis of 2-arylethyl arenesulfonates was studied by means of tracer techniques with deuterium and oxygen-18. 相似文献
5.
The resonance Raman spectra of tris(acetylacetonatoiron(III)) and ruthenium(III) complexes in various solvents and in water-acetonitrile (W-AN) mixtures were measured. The resonance Raman spectra of both complexes indicated peaks near 460 and around 1580 cm–1. Thev(C-O) peak (around 1580 cm–1) is shifted to low frequency with an increase in the dielectric constant T of the solvents, whereas thev(M-O) (M=Fe and Ru, near 460 cm–1) are constant, independent of T. It implies that the C-O bond in the acac– ligand is lengthened by the polarizability effect of the solvents, while both the Fe-O and Ru-O bonds, which are located in the inside of the complexes, are not influenced by the solvents indicating that the interaction does not depend on the properties of individual solvent molecules but on those of the aggregate. 相似文献
6.
Determination of l‐tryptophan and l‐kynurenine derivatized with (R)‐4‐(3‐isothiocyanatopyrrolidin‐1‐yl)‐7‐(N,N‐dimethylaminosulfonyl)‐2,1,3‐benzoxadiazole by LC‐MS/MS on a triazole‐bonded column and their quantification in human serum
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Shuuhei Takahashi Hideaki Iizuka Ryousuke Kuwabara Yoko Naito Tatsuya Sakamoto Aya Miyagi Mayu Onozato Hideaki Ichiba Takeshi Fukushima 《Biomedical chromatography : BMC》2016,30(9):1481-1486
The concentrations of l ‐tryptophan (Trp) and the metabolite l ‐kynurenine (KYN) can be used to evaluate the in‐vivo activity of indoleamine 2,3‐dioxygenase (IDO) and tryptophan 2,3‐dioxygenase (TDO). As such, a novel method involving derivatization of l ‐Trp and l ‐KYN with (R)‐4‐(3‐isothiocyanatopyrrolidin‐1‐yl)‐7‐(N,N‐dimethylaminosulfonyl)‐2,1,3‐benzoxadiazole (DBD‐PyNCS) and separation by high‐performance liquid chromatography (HPLC) with tandem mass spectrometric (MS/MS) detection on a triazole‐bonded column (Cosmosil HILIC®) was developed to determine their concentrations. The optimized mobile phase, CH3CN/10 mm ammonium formate in H2O (pH 5.0) (90:10, v/v) eluted isocratically, resulted in satisfactory separation and MS/MS detection of the analytes. The detection limits of l ‐Trp and l ‐KYN were approximately 50 and 4.0 pm , respectively. The column temperature affected the retention behaviour of the Trp and KYN derivatives, with increased column temperatures leading to increased capacity factors; positive enthalpy changes were revealed by van't Hoff plot analyses. Using the proposed LC‐MS/MS method, l ‐Trp and l ‐KYN were successfully determined in 10 μL human serum using 1‐methyl‐l ‐Trp as an internal standard. The precision and recovery of l ‐Trp were in the ranges 2.85–9.29 and 95.8–113%, respectively, while those of l ‐KYN were 2.51–16.0 and 80.8–98.2%, respectively. The proposed LC‐MS/MS method will be useful for evaluating the in vivo activity of IDO or TDO. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
7.
8.
Hirohito Ikeda Yukiko Sano Tomonori Matsubara Mitsunobu Kawahara Miho Yukawa Masao Fujisawa Eiji Yukawa Hatsumi Aki 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1135-1138
Propericiazine (PCZ) is an antipsychotic agent used for the treatment and the prevention of relapse of schizophrenia. We found that when an oral solution containing PCZ was mixed with a green tea drink, the residual content of PCZ was reduced by forming an insoluble complex between PCZ and tea polyphenol. In this study, the mechanism underlying the incompatibility of PCZ with green tea polyphenol (GTP) in the solution was clarified by isothermal titration microcalorimetry (ITC). Both solutions of 27.4 mM PCZ and 2.2 mM (?)-epigallocatechin gallate (EGCg), which is a main ingredient of GTP, were mixed and then PCZ in the filtrate was reduced to approximately 60 %. According to measurement at 298 K by ITC, PCZ formed an insoluble complex with EGCg at an associate constant (K) of 4.75 × 102 M?1 exothermically, ΔH = ?40.0 kJ mol?1. When (?)-epicatechin gallate (ECg) was used as the GTP, PCZ interacted with ECg with K and ΔH values of 3.74 × 102 M?1 and ?22.1 kJ mol?1, respectively. On the other hand, little heat of the reaction between PCZ and (?)-epigallocatechin or (?)-epicatechin was observed. The results indicated that the main reason for this incompatibility was the formation of an insoluble complex by PCZ and a gallate-type GTP such as EGCg and ECg in the aqueous solution. 相似文献
9.
10.
A microscopic theory of heavy-ion reactions is proposed based on the assumption that the set of antisymmetrizsd products of shell-model wave functions spans the complete Hilbert space of the system. The many-body Schrödinger equation and the equations given by the scattering theory of Ekstein are represented by the basis set, fully taking the Pauli principle into account. A set of coupled equations, which resembles that of the generator coordinate method, is obtained and reduced to a set of coupled integro-differential equations which leads to a simple physical picture for the scattering process of complex particles. 相似文献