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21.
Satoru Simizu N.S. Vander Ven S.A. Friedberg 《Journal of Physics and Chemistry of Solids》1982,43(4):373-375
EPR spectra of the 59Co+2 ion in oriented crystals of Mg(CH3COO)2·4H2O have been measured at 9.4 GHz and a temperature of 4.2 K. The data for each of the two metal ion sites per unit cell are well-described by a spin Hamiltonian for with gx = 6.13, gy = 389, gz = 2.49 and Ax = 0.0193, Ay' = 0.075, Az' = 0.0032 cm?1. Only the x-axes of the g- and A-tensors coincide. Orientation of the principal directions relative to the crystal axes has been established for the g- and A-tensors at both sites. They are consistent with the weakly ferromagnetic canted antiferromagnetism found in Co(CH3COO)2·4H2O below TN ?85mK. 相似文献
22.
Structural and thermodynamic data reported in the literature for the three crystalline phases of ferrocene are used to build a topological representation of its (p, T) phase diagram. Two phases (orthorhombic and monoclinic) exhibit stable phase regions whose temperature ranges increase with increasing pressure. The triclinic phase is found to be metastable at any temperature and pressure. In fact, in the (p, T) diagram, it is not associated with any state of lowest energy although it transforms into the monoclinic phase according to a transition which is reversible. This transition occurs in the phase region where the orthorhombic phase is the stable one. 相似文献
23.
Novel heparan sulfate mimetic compounds as antitumor agents 总被引:2,自引:0,他引:2
Heparan sulfate glycosaminoglycans (HSGAGs) are involved in tumor cell growth, adhesion, invasion, and migration, due to their interactions with various proteins. In this study, novel HSGAG-mimetic compounds (KI compounds) were designed and synthesized. As a result of cell-based assays, KI-105 was found to exert potent inhibitory activities against migration and invasion of human fibrosarcoma HT1080 cells. The present results indicate that a novel invasion/migration inhibitor, KI-105, can increase the adherence of HT1080 cells. It was conceivable that this cellular effect was caused by an increase in the amount of cell-surface HSGAGs and focal adhesions. Although further investigations are needed to decipher the molecular mechanism of KI-105, it is suggested that heparanase and Cdc42 are involved in its biological effects. 相似文献
24.
Naoki Kanoh Aya Asami Makoto Kawatani Kaori Honda Saori Kumashiro Hiroshi Takayama Siro Simizu Tomoyuki Amemiya Yasumitsu Kondoh Satoru Hatakeyama Keiko Tsuganezawa Rei Utata Akiko Tanaka Shigeyuki Yokoyama Hideo Tashiro Hiroyuki Osada 《化学:亚洲杂志》2006,1(6):789-797
We have developed a unique photo‐cross‐linking approach for immobilizing a variety of small molecules in a functional‐group‐independent manner. Our approach depends on the reactivity of the carbene species generated from trifluoromethylaryldiazirine upon UV irradiation. It was demonstrated in model experiments that the photogenerated carbenes were able to react with every small molecule tested, and they produced multiple conjugates in most cases. It was also found in on‐array immobilization experiments that various small molecules were immobilized, and the immobilized small molecules retained their ability to interact with their binding proteins. With this approach, photo‐cross‐linked microarrays of about 2000 natural products and drugs were constructed. This photo‐cross‐linked microarray format was found to be useful not merely for ligand screening but also to study the structure–activity relationship, that is, the relationship between the structural motif (or pharmacophore) found in small molecules and its binding affinity toward a protein, by taking advantage of the nonselective nature of the photo‐cross‐linking process. 相似文献
25.
M R Siro T L?vgren 《Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry》1978,32(6):447-451
An alpha-glucosidase was purified from baker's yeast. The molecular weight was approximately 44 000 daltons. SDS-disc gel electrophoresis suggested that the enzyme consisted of four subunits. The isoelectric point was at pH 5.4. The Km values for p-nitrophenyl alpha-D-glucopyranoside and maltose were 2.9 X 10(-4) and 2.5 X 10(-2) M, respectively. Binding of 2-(p-toluidino)naphthalene-6-sulfonate to the alpha-glucosidase was associated with a strong increase in fluorescence. The dissociation constant of the enzyme-TNS complex was 8 X 10(-5) M. The fluorescent probe did not interfere with the binding of glucose to the enzyme although the alpha-glucosidase was inhibited by high concentrations of TNS. The formation of an enzyme-glucose complex was indicated by an increase of fluorescence and by a shift in the wavelength for maximal emission which suggests that the binding process is associated with a change in conformation. The dissociation constant of the glucose--alpha-glucosidase complex KD = 0.57 X 10(-3) M, was calculated from the increase in fluorescence as a function of glucose concentration. 相似文献
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27.
Siro Medici 《Rendiconti del Circolo Matematico di Palermo》1908,26(1):128-144
28.
Siro Medici 《Rendiconti del Circolo Matematico di Palermo》1977,26(1):128-144