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21.
In the course of a population study of alpha 1-antitrypsin polymorphism by separator isoelectric focusing, a variant phenotype having a somewhat narrower spacing than PI M1M3 was observed in a Japanese blood donor. Family studies by hybrid isoelectric focusing in a carrier ampholyte-supplemented immobilized pH gradient from 4.35-4.65 revealed that the products of the responsible gene, PI*Mtoyoura, were extremely close but slightly cathodal to those of PI*M1. The difference in isoelectric point between them corresponded to the resolving limit of isoelectric focusing. For this reason, although the propositus' father was deduced to have the genotype PI*M1/PI*Mtoyoura, the products of these two genes failed to form a double band pattern. Thus, the gene frequency for PI*Mtoyoura was unknown. These findings, however, indicate that a further microheterogeneity in the PI M subtype exists at least in the Japanese. 相似文献
22.
23.
Christoph Elschenbroich Fabian Gerson Hiroaki Ohya-Nishiguchi Christoph Wydler Axel Nissen 《Helvetica chimica acta》1977,60(8):2530-2538
Proton hyperfine data are reported for the radical anions of 1,8-di (propyn-1-yl)-naphthalene (I), 7,8,12,13-tetradehydro-10,11-dihydro-9H-cyclodeca[d,e]naphthalene (II) and 2,2′-di(propyn-1-yl)-biphenyl (III), as well as of 5,6,11,12-tetradehydro-7,8,9,10-tetrahydro-dibenzo[a,c]cyclodecene (IV) and its 8,8,9,9-tetradeuterio-derivative (IV-d4). The triple bonds in I and II can be regarded as roughly parallel, while those in IV (and IV-d4) may be considered as crossed. The π-spin distributions in I? to IV? are discussed in terms of simple MO models which suggest a weekly bonding interaction between the acetylenic fragments in IV?, in contrast to III? where such an effect appears to be negligible. The importance of an analogous interaction in I? and II? is difficult to deduce, since its inclusion into a MO model does not substantially affect the π-spin distribution in these radical anions. 相似文献
24.
Yoshio Tanaka Morishige Atsukawa Yukio Shimura Akira Okada Hideki Sakuraba Tokuji Sakata 《Journal of polymer science. Part A, Polymer chemistry》1975,13(5):1017-1028
A soluble and self-crosslinkable linear copolymer with pendant epoxy and pyridyl groups was obtained from glycidyl methacrylate (M1) and 2-vinylpyridine (M2) or 2-vinyl-5-ethylpyridine (M2) by the action of azobisisobutyronitrile. The monomer reactivity ratios were determined in tetrahydrofuran at 60°C: r1 = 0.510, r2 = 0.620 with 2-vinylpyridine and r1 = 0.57, r2 = 0.62 with 2-vinyl-5-ethylpyridine. These were consistent with the calculated values with the reported Q and e values for these monomers. The intrinsic viscosities of the copolymers with 2-vinylpyridine and with 2-vinyl-5-ethylpyridine were found to be 0.17–0.19 and 0.26–0.38, respectively, in tetrahydrofuran at 30°C; they were independent of the copolymer composition. The copolymers were amorphous, had no clear melting points, and became insoluble crosslinked polymers under heating without further addition of any curing agents. 相似文献
25.
Koichi Tokuda Tatsuro Gueshi Hiroaki Matsuda 《Journal of Electroanalytical Chemistry》1979,102(1):41-48
Faradaic, impedances at model electrodes partially covered with a photoresist layer have been studied theoretically and experimentally. Equations for the faradaic impedance are derived based on the theoretical model and approach described in Part I of this series of papers. Experimental data for the hexacyanoferrate system at various model electrodes give excellent agreement, with theoretical predictions for the diffusion impedance behavior, and the applicability of the derived equations to the estimation of the degree of coverage and the size of the active regions is confirmed. Furthermore, the application of such model electrodes to the kinetic study of electrode reactions with high heterogeneous charge transfer rates is suggested. 相似文献
26.
The monomeric ν(N—H) vibrations of various trisubstituted ureas of the R2UPh type and -thioureas of the R2TUPh type have been studied. The trans—out isomerism in the former and the trans—out—cis isomerism in the latter are discussed from the point of view of steric effect. The monomeric ν(N—H) vibrations of RPhUPh and RPhTUPh are also examined. The single band appearing in the spectrum of both ureas is characteristic of the cis form; this suggests the existence of phenyl—phenyl interaction (the stacking interaction proposed by Galabov et al. [10]). Behavior of ν(N—H) vibrations at several concentrations is shown to be clearly different in the three forms (trans, out and cis). The presence of the cis form is confirmed by solvent effect experiments. 相似文献
27.
Isocyanide—mercuric chloride complexes react readily with an excess of primary and secondary amines to give guanidines and metallic mercury in high yields through a redox decomposition reaction. In the presence of triethylamine, isocyanide—mercuric chloride complexes react with an equimolar amount of a primary amine to give a carbodiimide and metallic mercury. An intermediate organomercuric compound was isolated in the reaction of the isocyanide—mercuric chloride complex with pyrrolidone. 相似文献
28.
Takeo Kawashiro Fumihiro Yamasawa Yasumasa Okada Hirosuke Kobayashi Kunio Tanabe 《Mathematical Programming》1991,52(1-3):1-9
The uneven distribution of ventilation—perfusion ratios (
) in diseased lungs is the major cause of arterial hypoxemia. Farhi and Yokoyama (1967) and Yokoyama and Farhi (1967) were the first who used physiologically inert gases as indicator gases to assess the uneven distribution of
Wagner and his coworkers in San Diego (1977b) extended the method and elaborated the multiple inert gas elimination technique in which blood flows in 50 compartments with different
were estimated based on data for 6 indicator gases. They analyzed the indicator gas data through an enforced smoothing technique with the ridge regression. To get smooth distributions, they introduced a weighting function for
compartments and an additional treatment for the non-negativity of the blood flow. The weighting function was empirically obtained. We analyzed the data without putting any weights on
compartments nor any additional treatment for non-negativity of blood flow. The analytical method in the present study was a modified Newton method, which is one of the enforced smoothing method. Our method was capable of recovering all distribution patterns that were found through the method reported by Wagner et al. (1977b). 相似文献
29.
30.