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41.
Nucleotide sequence of 5S ribosomal RNA from Lingula anatina. A study on the molecular evolution of 5S ribosomal RNA from a living fossil 总被引:8,自引:0,他引:8
By chromatography on columns of DEAE-Sephadex A-50 and Sephadex G-100, and electrophoresis on polyacrylamide gel, 5S rRNA was purified from a low-molecular-weight RNA fraction extracted from the total tissues of Lingula anatina. Complete digests of the 5S rRNA with RNase T1 [EC 3.1.4.8] and pancreatic RNase [EC 3.1.4.22] were sequenced by conventional column chromatography procedures. The nucleotide sequence of this RNA was determined mainly by a chemical method for sequencing the RNA 3' end-labeled with 32P (1), with the complement of the oligonucleotide catalog obtained by the complete RNase digestions of the RNA. By comparing the sequences of several invertebrate, vertebrate, and Chlorella 5S rRNAs, a phylogenic tree of the rRNAs was constructed and the time of divergence of Lingula was estimated. 相似文献
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In order to compare the acute effects of three kinds of antithyroid agents of iodide (I-), propylthiouracil (PTU) and PTU combined with iodide (PTU+I-) on thyroid function in hyperthyroid patients with diffuse goiter, serum concentrations of thyroxine (T4), triiodothyronine (T3), T3-resin sponge uptake (T3-RU) and free thyroxine index (FT4I) were employed as thyroid function parameters. In the group given iodine (1 mg/day) as iodinated-lecithine, the initial values of T4, T3, T3-RU and FT4I were 20.9 +/- 1.6 microng/100 ml (T4), greater than 740 ng/100 ml (T3), 49.5 +/- 2.3% (T3-RU) and 14.7 +/- 1.8 (FT4I). At the end of one week of therapy, they decreased clearly to 15.6 +/- 2.2 microng/100 ml, 457 +/- 87 ng/100 ml, 42.2 +/- 4.0% and 9.7 +/- 2.4. The so-called "escape phenomenon" from iodide inhibition was observed in serum T4, T3-RU and FT4I values at the end of two weeks of iodide therapy, while serum T3 continued to decrease but the value of T3 was far outside of the normal range. In the PTU group (300 mg/day), thyroid function parameters were 22.5 +/- 0.8 microng/100 ml (T4), greater than 592 ng/100 ml (T3), 54.9 +/- 1.0% (T3-RU) and 18.7 +/- 1.0 (FT4I) before treatment. They decreased continually week by week. At the end of four-week treatment with PTU, the value of each thyroid function parameter was 11.1 +/- 1.9 microng/100 ml, 229 +/- 56 ng/100 ml, 36.6 +/- 4.4% and 5.7 +/- 1.7. In the group of hyperthyroidism simultaneously given both PTU and iodide (300 mg/PTU and 1 mg/iodine), these thyroid function parameters decreased as well as in the group treated with PTU alone for more than two weeks. More rapid or significant decrease of T4, T3, T3-RU and ft4i in PTU+I- group than in PTU group was observed in the present study. These results suggested strongly that iodide alone was not an adequate therapy for hyperthyroidism as well known and they were also compatible with the idea that the concomitant administration of PTU and iodide was more effective in the early phase of therapy of hyperthyroidism than PTU alone. 相似文献
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Irine Yunhafita Malya Jing Wu Etsuko Harada Masaaki Toda Corina N. D’Alessandro-Gabazza Taro Yasuma 《Bioscience, biotechnology, and biochemistry》2020,84(7):1332-1338
ABSTRACT A novel compound, (R)-4-ethoxy-2-hydroxy-4-oxobutanoic acid (1), and six known compounds (2–7) were isolated from the fruiting bodies of the wild edible mushroom Leucopaxillus giganteus. The planar structure of 1 was determined by the interpretation of spectroscopic data analysis. The absolute configuration of 1 was determined by comparing specific rotation of the synthetic compounds. In the plant regulatory assay, the isolated compounds (1–7) and the chemically prepared compounds (8–10) were evaluated their biological activity against the lettuce (Lactuca sativa) growth. Compounds 1 and 3–10 showed the significant regulatory activity of lettuce growth. 1 showed the strongest inhibition activity among the all the compounds tested. In the lung cancer assay, all the compounds were assessed the mRNA expression of Axl and immune checkpoints (PD-L1, PD-L2) in the human A549 alveolar epithelial cell line by RT-PCR. Compounds 1–10 showed significant inhibition activity against Axl and/or immune checkpoint. 相似文献
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Takemura Aya Matsumoto Junya Hashimoto Ryota Kawano Kenji Miura Kenichiro 《Journal of computational neuroscience》2021,49(3):273-282
Journal of Computational Neuroscience - When two-frame apparent motion stimuli are presented with an appropriate inter-stimulus interval (ISI), motion is perceived in the direction opposite to the... 相似文献
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Baowei Jiao Naoko Taniguchi-Ishigaki Cenap Güng?r Marvin A. Peters Ya-Wen Chen Sabine Riethdorf Alexander Drung Leanne G. Ahronian JongDae Shin Rachna Pagnis Klaus Pantel Taro Tachibana Brian C. Lewis Steven A. Johnsen Ingolf Bach 《Molecular biology of the cell》2013,24(19):3085-3096
The X-linked gene Rnf12 encodes the ubiquitin ligase really interesting new gene (RING) finger LIM domain–interacting protein (RLIM)/RING finger protein 12 (Rnf12), which serves as a major sex-specific epigenetic regulator of female mouse nurturing tissues. Early during embryogenesis, RLIM/Rnf12 expressed from the maternal allele is crucial for the development of extraembryonic trophoblast cells. In contrast, in mammary glands of pregnant and lactating adult females RLIM/Rnf12 expressed from the paternal allele functions as a critical survival factor for milk-producing alveolar cells. Although RLIM/Rnf12 is detected mostly in the nucleus, little is known about how and in which cellular compartment(s) RLIM/Rnf12 mediates its biological functions. Here we demonstrate that RLIM/Rnf12 protein shuttles between nucleus and cytoplasm and this is regulated by phosphorylation of serine S214 located within its nuclear localization sequence. We show that shuttling is important for RLIM to exert its biological functions, as alveolar cell survival activity is inhibited in cells expressing shuttling-deficient nuclear or cytoplasmic RLIM/Rnf12. Thus regulated nucleocytoplasmic shuttling of RLIM/Rnf12 coordinates cellular compartments during mammary alveolar cell survival. 相似文献