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91.
M Ariyoshi K Nagata K Sato M Kubo K Hiraoka T Hamada G Tadakuma T Abe A Inoue 《Canadian Metallurgical Quarterly》1997,44(2):135-139
The displacement of porcine [125I] insulin bound to rat and lamprey isolated hepatocytes with unlabeled lamprey and porcine insulins was investigated. Binding affinity of lamprey insulin for insulin receptor of rat was similar to that of porcine insulin. In contrast, the binding affinity of lamprey insulin for its own insulin receptor was higher than for a rat receptor. To determine the binding affinity constants of lamprey insulin receptor, the competition binding experiments were carried out on isolated lamprey hepatocytes using lamprey insulin as unlabeled ligand and tracer. The affinity of the same binding sites on lamprey hepatocytes was assessed in similar experiments but employing porcine insulin as unlabeled ligand and tracer. It was found that while Kd of low affinity binding sites on lamprey hepatocytes were similar for lamprey and porcine insulins, the Kd of high affinity binding sites was different: the displacement curve for lamprey insulin being shifted to the left as compared to the curve for porcine insulin. The number of high and low affinity binding sites, calculated independently in Scatchard plots, was equal. We conclude that the high affinity insulin binding sites of lamprey but not of rat hepatocytes reveal some species specificity in ligand-receptor interaction. 相似文献
92.
One hundred and twelve forearms in 56 preserved cadavers were dissected to assess the incidence of Martin-Gruber connections in a population in South Africa. The connections were found in 13 cadavers (23%) and one was bilateral. There were no significant racial or sexual differences in the incidence. The course of Martin-Gruber connections and their anatomical relationship with the ulnar artery are illustrated. 相似文献
93.
We propose a novel signal scanning method using a tree structure of automata. This method has a kind of image compression capability, about 1/6–1/20 for samples images, by skipping the scan of non-active elements with a selectively activated signal path only to active elements. We also demonstrate the effect of data compression for some examples and an implementation of tree structure on a VLSI chip. 相似文献
94.
Summary Propylene polymerization was performed with a highly active MgCl supported TiCl4 in conjunction with Et3Al and ethyl benzoate (EB). The obtained polypropylene sample was separated into four fractions by successive extraction with pentane, heptane and trichloroethylene (trichlene). Yield, Mn, Tm and microtacticity of each fraction were determined, and the effects of the concentration of EB on these items of results were investigated. It has been found that EB enhances yield, Mn and stereospecificity of trichlene insoluble (the most stereospecific) fraction, and in contrast, it decreases rapidly yields of other three fractions without changing the character of the polymers. From these findings, the functions of EB to the active centers were discussed. 相似文献
95.
LIM-kinase 1 (LIMK1) and 2 (LIMK2) are members of a novel class of protein kinases containing two LIM motifs at the N-terminus. The LIM motif is thought to be involved in protein-protein interactions. We report here evidence that LIMK1 self-associates and also associates with LIMK2. In vivo and in vitro binding analyses using variously deleted mutants of LIMKI revealed that the self-association of LIMK1 was caused by interaction between the N-terminal LIM domain and the C-terminal kinase domain. The association of LIMK1 with itself and with LIMK2 is important for understanding how activities and functions of LIMK family kinases are regulated. 相似文献
96.
97.
Compound classes in coal liquids were investigated by thin-layer chromatography coupled with a flame ionization detector (t.l.c.-f.i.d.). Individual t.l.c. peaks for coal liquids were identified as paraffins, aromatics, polar compounds and more strongly polar compounds or asphaltenes in order of increasing Rf values by comparison with specific compounds separated previously by conventional liquid chromatography. Concentrations of compound classes for a series of samples obtained by varying the hydrogenation time were estimated and good agreement was found with the results obtained by the USBM-API 60 liquid chromatography procedure. By using the t.l.c.-f.i.d. method, the relation of distribution of compound classes to the reaction conditions of coal hydrogenation could be derived quantitatively with relative ease. 相似文献
98.
K Nabeshima T Nakagawa AF Straight A Murray Y Chikashige YM Yamashita Y Hiraoka M Yanagida 《Canadian Metallurgical Quarterly》1998,9(11):3211-3225
In higher eukaryotic cells, the spindle forms along with chromosome condensation in mitotic prophase. In metaphase, chromosomes are aligned on the spindle with sister kinetochores facing toward the opposite poles. In anaphase A, sister chromatids separate from each other without spindle extension, whereas spindle elongation takes place during anaphase B. We have critically examined whether such mitotic stages also occur in a lower eukaryote, Schizosaccharomyces pombe. Using the green fluorescent protein tagging technique, early mitotic to late anaphase events were observed in living fission yeast cells. S. pombe has three phases in spindle dynamics, spindle formation (phase 1), constant spindle length (phase 2), and spindle extension (phase 3). Sister centromere separation (anaphase A) rapidly occurred at the end of phase 2. The centromere showed dynamic movements throughout phase 2 as it moved back and forth and was transiently split in two before its separation, suggesting that the centromere was positioned in a bioriented manner toward the poles at metaphase. Microtubule-associating Dis1 was required for the occurrence of constant spindle length and centromere movement in phase 2. Normal transition from phase 2 to 3 needed DNA topoisomerase II and Cut1 but not Cut14. The duration of each phase was highly dependent on temperature. 相似文献
99.
100.
Effect of polymerization temperature on the phase-separated structure of the composite materials [P(St-DVB)/PVC systems] prepared by copolymerization of styrene (St) and divinylbenzene (DVB) in the presence of fine poly(vinyl chloride) (PVC) powder was studied by electron microscopy and dynamic mechanical test. P(St-DVB)/PVC systems have the two-phase nature with a styrene-divinylbenzene copolymer as the continuous phase [P(St-DVB) phase) and a PSt/PVC composite as the dispersed phase (PSt-PVC phase), in which PSt penetrates into the PVC domain. The crosslinking density of the P(St-DVB) phase is larger than that estimated from the recipe in the feed, suggesting that there exists a difference of the diffusion constants of styrene and divinylbenzene into the PVC particles on the paste formation and the polymerization process. The changes of the phase-separated structure of P(St-DVB)/PVC systems polymerized at various temperatures are also explained on the basis of the difference between the diffusion behavior of styrene and that of divinylbenzene into fine PVC particles at these temperatures. 相似文献