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641.
Konosuke Sano Chikahiko Eguchi Naohiko Yasuda Koji Mitsugi 《Bioscience, biotechnology, and biochemistry》2013,77(11):2373-2374
Replication factor C (RFC) catalyzes the assembly of circular proliferating cell nuclear antigen (PCNA) clamps around primed DNA, enabling processive synthesis by DNA polymerase. The RFC-like genes, arranged in tandem in the Thermococcus kodakaraensis KOD1 genome, were cloned individually and co-expressed in Escherichia coli cells. T. kodakaraensis KOD1 RFC homologue (Tk-RFC) consists of the small subunit (Tk-RFCS: MW=37.2 kDa) and the large subunit (Tk-RFCL: MW=57.2 kDa). The DNA elongation rate of the family B DNA polymerase from T. kodakaraensis KOD1 (KOD DNA polymerase), which has the highest elongation rate in all thermostable DNA polymerases, was increased about 1.7 times, when T. kodakaraensis KOD1 PCNA (Tk-PCNA) and the Tk-RFC at the equal molar ratio of KOD DNA polymerase were reacted with primed DNA. 相似文献
642.
Hikaru Tanaka Mikiharu Yoshida Tsuneo Ishiguro Chikahiko Eguchi Ikuya Nonaka Eijiro Ozawa 《Protoplasma》1989,152(2-3):109-111
Summary We examined the morphological expression of dystrophin in the intrafusal muscle fibers in skeletal muscle from normal human and Duchenne muscular dystrophy (DMD) patients, using antisera against the N-terminal and C-terminal regions of dystrophin. The intrafusal fibers of normal muscle express dystrophin on their cell surface membrane, but those of DMD muscle do not.Abbreviation DMD
Duchenne muscular dystrophy 相似文献
643.
644.
M Yamamoto M Toguchi K Arishima Y Eguchi J Leichter M Lee 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1989,191(4):382-386
To investigate the effect of maternal alcohol consumption on the development of the fetal thyroid gland, Sprague-Dawley rats were given 20% ethanol for 4 weeks prior to mating and 30% ethanol throughout gestation. Pair-fed controls received an isocaloric amount of corn starch and chow, with water ad libitum, and ad libitum controls received rat chow and water. On Days 17, 18, 19, and 20 of gestation, the fetuses were weighed and the fetal thyroids were removed for histometric observation. On Days 19 and 20, the fetal thyroids of alcohol-exposed fetuses weighed significantly less than those of the two control groups, but more than the control thyroids 1 day earlier. Maternal alcohol consumption caused a significant decrease in both the follicular cell height and the follicle diameter of the fetal thyroid on all days examined. In the alcohol group on Days 19 and 20 of gestation, the cell height was less than, and the follicle diameter was approximately equal to those in the two controls 2 days earlier. These results indicate that, as a consequence of maternal alcohol consumption, growth of the fetal thyroid gland is retarded, and there are indications of fetal hypothyroidism, as seen from the histometric data. This latter is suggestive of a retarded thyrotropic activity of the fetal pituitary gland. 相似文献
645.
K Watanabe H Aoyama N Tamamaki T Sonomura T S Okada G Eguchi Y Nojyo 《Development (Cambridge, England)》1988,103(1):17-26
The differentiating potency of pineal cells from 8-day quail embryos was studied with cell culture. It was found that the differentiation of striated muscle fibres occurred abundantly in the pineal cells cultured in hypertonic culture conditions. Muscle nature of these fibres was confirmed by utilizing the antiserum against the striated muscle type creatine kinase (MM-CK). When CO2, NAHCO3, NaCl, KCl and MgCl2 were added in hypertonic concentrations, extensive myogenesis occurred in cultured pineal cells. Myogenesis in pineal cultures began as early as 2 days and, after 3 days in the medium with 75 mM additional NaCl, reached 100-fold when compared with that in the isotonic medium. Muscle fibres from pineal cells in culture were similar in morphology to the skeletal muscle fibres of mesodermal origin in situ. Myogenesis of pineal cells under hypertonic conditions was accompanied by the synthesis of a unique 56 x 10(3) Mr protein, which was not found in the intrinsic muscle cells. Clonal cell culture revealed that about 80% of clonable pineal cells were myogenic precursors. Pineal cells of 8-day quail embryos were not only myogenic but oculopotent (melanogenic and lentoidogenic) in cultures. This study examined whether multipotential progenitor cells with both potentials are present in the pineal or not. The results showed that at least 16% of all clonable pineal cells were multipotent precursors. The embryonic pineal is considered to be a typical multipotent system in parallel with the pigmented and neural retina, the neural crest and the teratocarcinoma. 相似文献
646.
Y Iwama M Eguchi 《Virchows Archiv. B, Cell pathology including molecular pathology》1986,51(5):375-384
Mitochondria from 25 patients with acute lymphoblastic leukemia (ALL) and 25 patients with acute myelogenous leukemia (AML) were compared in terms of their number, area, and shape index using a computer-controlled image analyzer. The number of mitochondria was greater in the AML than in the ALL patients. However, their size, as measured in electron micrographic profiles was similar in the two groups, in disagreement with conventional reports that mitochondria are small in granulocytes but large in lymphocytes. Two ALL patients had giant mitochondria. The mitochondria of the ALL cells were more irregular than those of the AML cells, and furthermore, within the ALL group, the degree of the irregularity was greater in those with a poor prognosis than in those in longstanding remission. The number of mitochondria was significantly greater in B-cell ALL than in null cell and T-cell ALL. 相似文献
647.
A method was developed for estimating the mortality during a die-off of marine mammal species from longitudinal stranding data. A deterministic mathematical model of the stranding process was used to calculate the mortality during a die-off. The model incorporated natural and anthropogenic mortality rates, the number of stranded carcasses before, during, and after the die-off, the duration of the die-off, and detection probability of a stranded carcass. The model was applied to data for the bottlenose dolphin ( Tursiops truncatus ) along the Atlantic coast of the United States. The mortality rate during the epizootic of 1987 and 1988 was calculated using the model. Sensitivity analyses indicated that precise estimates of natural and anthropogenic mortality rates were important for obtaining precise additional mortality rates during the die-off. For stranding data to be useful in this model, data should be collected in a consistent manner and effort within a defined area prior to, throughout, and after a die-off. Survey effort also should be measured. 相似文献
648.
2,2'-Anhydro-1-(3'-deoxy-3'-iodo-5'-O-trityl-beta-D-arabinofuranosyl) thymine (2) was synthesized from 2',3'-didehydro-3'-deoxythymidine (DHT). Compound 2 was readily converted into the 2',3'-anhydrolyxofuranosyl derivatives 4-6. Treatment of 4a with some nucleophiles (N3-, OMe-, Cl-) gave the corresponding 3'-substituted arabinosyl nucleosides (7a,c,e) together with the minor xylosyl isomers (8a,c,d). 7a,c,e were deprotected to 7b,d,f, respectively. 相似文献
649.
Studies on the mechanism of blastula formation in starfish embryos denuded of fertilization membrane
A starfish egg, denuded of the fertilization membrane and placed on a glass surface, becomes a cell monolayer after several cleavages. This sheet of cells folds and forms a hollow sphere resembling a normal blastula at the 2(9)-2(10)-cell stage ('closing movement'). A marked morphological change was observed in each cell, preceding the closing movement. The surface of each blastomere differentiated into two parts: one was smooth, whereas the other was rough with microvilli. The smooth surface was more adhesive and flexible than the rough surface, suggesting that the closing movement may be driven by a local increase in cell adhesiveness. 相似文献
650.