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121.
S Nonoyama A Etzioni H Toru DP Ruggerie D Lewis S Pollack A Aruffo JI Yata HD Ochs 《Canadian Metallurgical Quarterly》1998,28(2):589-598
Major histocompatibility complex (MHC) class II deficiency (bare lymphocyte syndrome, BLS) is a rare primary immunodeficiency classified as a subgroup of severe combined immunodeficiency. We studied T and B lymphocyte function by examining the CD40 ligand/CD40 system in three BLS patients from two unrelated families. CD40 ligand expression by maximally activated BLS T cells was diminished. This abnormality may represent immunological na?veté rather than a general T cell defect, since expression of activation marker CD69 and proliferative responses to PHA or anti-CD3 were normal, and BLS T cells primed and restimulated in vitro expressed normal amounts of CD40 ligand. BLS B cells proliferated and produced IgE if stimulated with anti-CD40 or soluble CD40 ligand and IL-4. Activation of BLS B cells with soluble CD40 ligand and IL-4 induced normal expression of activation markers, although MHC class II expression remained absent. Depressed antibody titers, lack of amplification and failure to undergo isotype switching in response to immunization with bacteriophage phi x 174 demonstrated defective T cell help. We conclude that BLS B cells are functionally normal if appropriately stimulated, and that the defective humoral immunity observed may be related to diminished expression of CD40 ligand on BLS T cells. 相似文献
122.
Rapid and practical separations of 1,2-and 2,3-diacyl-and dialkyl-sn-glycerol enantimers as their 3,5-dinitrophenylurethane derivatives were carried out by normal-phase high performance liquid
chromatography on a chiral stationary phase, N-(R)-1-(α-naphthyl)ethylaminocarbonyl-(S)-valine chemically bonded to γ-aminopropyl silanized silica. Complete separations of the racemates into enantiomers were
achieved for both of the diacyl-and dialkylglycerols within 10 min using a stainless steel column (25 cm long) packed with
the 5-μ particles, an isocratic elution with a mixture of hexane/ethylene dichloride/ethanol as a mobile phase and a UV detector.
Thesn-1,2-enantiomers were eluted ahead of the correspondingsn-2,3-enantiomers. Satisfactory separation of thesn-1,3-diacylglycerols from the corresponding enantiomers and the separation of the homologues differing in acyl and alkyl groups
were also observed. The formations of hydrogen bonding and charge transfer complex between the urethane derivatives and the
stationary phase may contribute to the enantiomer separations. 相似文献
123.
Toru Takagi Naoko Wakasa Kazuo Miyashita 《Journal of the American Oil Chemists' Society》1987,64(9):1320-1323
The determination of conjugated diene formation revealed that the mol % conversions of allcis-6,9,12-octadecatrienoic acid [γ-linolenic, 18:3(n-6)], allcis-5,8,11,14-eicosatetraenoic acid [arachidonic, 20:4(n-6)], allcis-5,8,11,14,17-eicosapentaenoic acid [20:5(n-3)], and allcis-4,7,10,13,16,19-docosahexaenoic acid [22:6(n-3)] into conjugated diene products by soybean lipoxygenase-1 at pH 9.0 were
84, 86, 60 and 40% of that of allcis-9,12-octadecadienoic acid [linoleic, 18:2(n-6)], respectively. On the other hand, the conversions of allcis-9,12,15-octadecatrienoic acid [α-linolenic, 18:3(n-3)], allcis-5,9,12-octadecatrienoic acid (c5,c9,c12-18:3), andtrans-5,cis-9,cis-12-octadecatrienoic acid (t5,c9,c12-18:3) were equal to that of 18:2(n-6). The lowering of the conjugated diene formation
in the oxidation of 18:3(n-6), 20:4(n-6), 20:5(n-3), and 22:6(n-3) by the lipoxygenase was thought to be caused by the further
oxidation of conjugated diene monohydroperoxides to yield conjugated triene products. For this reason, the conventional lipoxygenase
method gave erroneous values forcis,cis-methylene interrupted polyunsaturated fatty acids (PUFA) in oils containing a large amount of 20:5(n-3) and 22:6(n-3) such
as fish oils. However, by changing the pH of reaction mixtures from 9.0 to 11.0, the secondary oxidation of conjugated diene
monohydroperoxides was completely inhibited, and the PUFA values in fish oils obtained by this improved method were in good
agreement with those obtained by a GLC method. 相似文献
124.
Summary Oxochloro(5,10,15,20-tetraphenylporphyrinate)molybdenum (V) was physically entrapped into poly (styrene) by lyophilizing a benzene solution including both complex and polymer. The functional ability of the obtained complex-containing resin to adsorb H2PO4
– from an aqueous solution was investigated in the presence of various anions. It was found that the selectivity of the resin for H2PO4
– is superior to those of conventional anion exchangers. 相似文献
125.
The dynamic moduli, E′ and E″, and tan δ for PET–CR, PET–EPDM, and PET–UR composites with unidirectional short fibers were studied as a function of temperature by using a Rheovibron. The temperature dependence of tan δ showed three peaks for PET–elastomer composites. The peaks at the low temperature corresponded to the main dispersion of the respective matrixes and the peak at about 140°C to the α-dispersion of PET fiber. A small and broad peak observed at a temperature between 60 and 120°C may be caused by the relaxation of the interface region between fibers and matrix. The longitudinal storage modulus for the composite E was given by the parallel model as \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm E'}_\parallel = V_f \cdot E'_f + V_m \cdot E'_m $\end{document}, where E and E are the storage moduli for fiber and matrix and Vf and Vm are the volume fraction of fiber and matrix, respectively. In the transverse direction of fibers, the composite modulus E was expressed by the logarithmic law of mixing as follows: \documentclass{article}\pagestyle{empty}\begin{document}$ \log E'_ \bot = V_f \cdot \log E'_f + V_m \cdot \log E'_m $\end{document}. The peak values of tan δ from the main dispersion of the respective matrixes were given by the equation, (tan δ⊥max)c/(tan δmax)m 1 ? β · Vf, where (tan δ⊥max)c and (tan δmax)m are the maximum values of the loss tangent for the composite and matrix, respectively, and β is coefficient depending on matrix's type. The β value of PET–CR composite is the largest one among those of the composites. 相似文献
126.
Microscopic observation of carbons obtained from pure aromatic hydrocarbons by the aid of carbonization catalysts was carried out to clarify the microstructure of these carbons of different features. Reflected polarized-light microscopy distinguished needle, mosaic and isotropic cokes, former two of which were produced with aluminum chloride and the last with potassium. High resolution microscopy revealed that these carbons calcined at 1250° had different degree of layered structure, corresponding to the crystallographic parameters of these samples graphitized at 2500°C. The reasons for the carbons produced with potassium to be non-graphitizable are discussed from the macro- and micro-features of the carbons. 相似文献
127.
Toru Takagi 《Journal of the American Oil Chemists' Society》1964,41(7):516-519
Eicosatrienoic acid, the unique constituent acid ofPodocarpus nagi seed oil is characterized as all-cis-5,ll,14-eicosatrienoic acid. Bicosadienoic acid found in the same oil is shown to becis,cis-11,14-eicosadienoic acid.
1 Issued as NRC No. 7982.
2 National Research Council of Canada Postdoctorate Fellow, 1961-1962. 相似文献
128.
129.
Paveena Srirangsan Kiyoshi Kawai Naoko Hamada-Sato Manabu Watanabe Toru Suzuki 《Food chemistry》2010,119(1):209-213
In order to improve the remaining activity of a practically important freeze-dried enzyme, xanthine oxidase (XOD), the effects of disaccharide (sucrose and trehalose), polymer (bovine serum albumin: BSA and dextran) and a mixture of them on the loss of XOD activity during freeze-drying and subsequent storage were investigated. All samples were amorphous solids and their glass transition temperatures (Tg) were evaluated by using differential scanning calorimetry. Although dextran showed no stabilizing effect on the freeze-dried XOD, the others protected XOD from the activity loss during freeze-drying to a certain extent. It was found that the mixture of disaccharide (sucrose or trehalose) and BSA improved the XOD activity synergistically. The XOD activity of the samples decreased gradually during storage at a temperature range of between 25 and 60 °C. Samples stored at temperatures below the Tg showed a lower loss of XOD activity than those stored at just the Tg. 相似文献
130.
Masatoshi Kitakaze Ryota Chijimatsu Andrea Vecchione Toru Kitagawa Yuichiro Doki Hidetoshi Eguchi Hideshi Ishii 《International journal of molecular sciences》2021,22(14)
The recent advances in deciphering the human genome allow us to understand and evaluate the mechanisms of human genome age-associated transformations, which are largely unclear. Genome sequencing techniques assure comprehensive mapping of human genetics; however, understanding of gene functional interactions, specifically of time/age-dependent modifications, remain challenging. The age of the genome is defined by the sum of individual (inherited) and acquired genomic traits, based on internal and external factors that impact ontogenesis from the moment of egg fertilization and embryonic development. The biological part of genomic age opens a new perspective for intervention. The discovery of single cell-based mechanisms for genetic change indicates the possibility of influencing aging and associated disease burden, as well as metabolism. Cell populations with transformed genetic background were shown to serve as the origin of common diseases during extended life expectancy (superaging). Consequently, age-related cell transformation leads to cancer and cell degeneration (senescence). This article aims to describe current advances in the genomic mechanisms of senescence and its role in the spatiotemporal spread of epithelial clones and cell evolution. 相似文献