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81.
H Fushimi Y Kobayashi T Koyama M Miyata T Yamada Y Matsuyuki T Sugase K Shima S Tarui 《Endocrinologia japonica》1976,23(5):423-428
Endocrine functions were investigated in a case of "beta-adrenergic hyperdynamic circulatory state". This state was diagnosed by (1) typical symptoms of cardiac awareness, (2) physical findings (increments of pulse rate and blood pressure by changing positions or walking), (3) increase in cardiac output (5.25 l/min leads to 14.03 l/min) and decrease in circulatory time (10.8 sec leads to 5.5 sec) by isoproterenol infusion (0.02 mug/min/kg body weight), (4) rapid loss of symptoms and above findings by propranolol treatment (30 mg per os daily) and reappearance by discontinuing medication. The mechanism of insulin response to glucose has been a controversy as to whether the secretion is transmitted by beta-receptor or independent glucose receptor. And in this physiologic beta-adrenergic state, it was found that insulin responses in IVGTT and OGTT were within normal limit. When beta-adrenergic condition was corrected by propranolol treatment, insulin responses were shown lowered, though in the normal range. This could be reproduced by discontinuing medication. Insulin, glucagon and growth hormone secretions caused by arginine were also found normal, but during the period the patient was on propranolol therapy, all responses were decreased, within the normal range. These results do not positively support the idea that glucose receptor is linked to beta-receptor. They do not either agree with the contention that secretions of insulin, glucagon and growth hormone induced by arginine are mediated through beta-receptors. 相似文献
82.
Information has been obtained as a part of a wider study of leaf structure, water relations and mineral status, which is to include work on a considerable variety of evergreen forests. Fifteen structural features have been investigated in well-lit leaves of 60 dicotyledonous species of Japanese Warm Temperate Rain Forest, this sample giving an 81% cover of the relevant species (Table 1). The salient features of the average leaf are summarised on p. 200. The leaves of shrubs and small trees have been compared with those of tall and medium trees; some of the differences were unexpected. For example, the leaves of the lower growing species tended to be thicker and to have thicker outer walls. The leaves of the whole Japanese sample were compared with those of 40 species in Tropical Lowland Rain Forest in New Britain. Although the average leaf area of the Japanese species was less than one tenth of that of the species from New Britain, the thickness and internal structure of the leaf and the size and density of the stomata were quite similar in the two sets of leaves (Table 2). The Japanese leaves were somewhat more xeromorphic in that they had thicker outer walls in the upper and lower epidermis. 相似文献
83.
A DNA-binding protein, which migrated as one major protein band, with a molecular weight of 14,000, on sodium dodecylsulfate polyacrylamide gel, was purified from a culture medium of mouse thymus cells. The interaction of the isolated protein with DNA in vitro was assayed by a nitrocellulose filter binding technique. Equilibrium competition experiments demonstrated that the DNA-binding protein had the ability to differentiate among sequences of polynucleotides, indicating that the DNA-binding protein-DNA interaction was at least partially specific. This protein increased the helix melting temperature of DNA and inhibited the incorporation of [3H]dTMP into DNA by the DNA polymerase of calf thymus in vitro. 相似文献
84.
85.
Takimoto Yuki Monkawa Akira Nagata Kohki Kobayashi Masahiro Kinoshita Mariko Gessei Tomoko Mori Toshiya Kagi Hiroyuki 《Plasmonics (Norwell, Mass.)》2020,15(3):805-811
Plasmonics - Detection and monitoring of SO2 is important because it is a representative toxic gas in the atmospheric environment that is emitted from industrial and natural processes. Localized... 相似文献
86.
Hiroko Heijo Sora Shimogama Shuichi Nakano Anna Miyata Yasuhiro Iwao Yuki Hara 《Molecular biology of the cell》2020,31(24):2703
Cells adapt to drastic changes in genome quantity during evolution and cell division by adjusting the nuclear size to exert genomic functions. However, the mechanism by which DNA content within the nucleus contributes to controlling the nuclear size remains unclear. Here, we experimentally evaluated the effects of DNA content by utilizing cell-free Xenopus egg extracts and imaging of in vivo embryos. Upon manipulation of DNA content while maintaining cytoplasmic effects constant, both plateau size and expansion speed of the nucleus correlated highly with DNA content. We also found that nuclear expansion dynamics was altered when chromatin interaction with the nuclear envelope or chromatin condensation was manipulated while maintaining DNA content constant. Furthermore, excess membrane accumulated on the nuclear surface when the DNA content was low. These results clearly demonstrate that nuclear expansion is determined not only by cytoplasmic membrane supply but also by the physical properties of chromatin, including DNA quantity and chromatin structure within the nucleus, rather than the coding sequences themselves. In controlling the dynamics of nuclear expansion, we propose that chromatin interaction with the nuclear envelope plays a role in transmitting chromatin repulsion forces to the nuclear membrane. 相似文献
87.
Kanno Yosuke Shu En Niwa Hirofumi Seishima Mariko Ozaki Kei-ichi 《Molecular biology reports》2021,48(4):3431-3437
Molecular Biology Reports - Systemic sclerosis (SSc) is characterized by peripheral circulatory disturbance and fibrosis in skin and visceral organs. We recently demonstrated that... 相似文献
88.
89.
Shiho Ohnishi Mariko Murata Shinji Oikawa Yusuke Hiraku Shosuke Kawanishi 《Free radical research》2013,47(6):469-478
Hydrazobenzene is carcinogenic to rats and mice and azobenzene is carcinogenic to rats. Hydrazobenzene is a metabolic intermediate of azobenzene. To clarify the mechanism of carcinogenesis by azobenzene and hydrazobenzene, we investigated DNA damage induced by hydrazobenzene, using 32P-5′-end-labeled DNA fragments obtained from the c-Ha-ras-1 proto-oncogene and the p53 tumor suppressor gene. Hydrazobenzene caused DNA damage in the presence of Cu(II). Piperidine treatment enhanced the DNA damage greatly, suggesting that hydrazobenzene caused base modification and liberation. However, azobenzene did not cause DNA damage even in the presence of Cu(II). Hydrazobenzene plus Cu(II) caused DNA damage frequently at thymine residues. Catalase and a Cu(I)-specific chelator inhibited Cu(II)-mediated DNA damage by hydrazobenzene. Typical ·OH scavengers did not inhibit the DNA damage. The main active species is probably a metal oxygen complex, such as Cu(I)-OOH. Formation of 8-oxo-7, 8-dihydro-2′-deoxyguanosine was increased by hydrazobenzene in the presence of Cu(II). Oxygen consumption and UV-Visible spectroscopic measurements have shown that hydrazobenzene is autoxidized to azobenzene with H2O2 formation. It is considered that the metal-mediated DNA damage by hydrazobenzene through H2O2 generation may be relevant for the expression of carcinogenicity of azobenzene and hydrazobenzene. 相似文献
90.
Yasuhito Hamaguchi Manabu Fujimoto Takashi Matsushita Kenzo Kaji Kazuhiro Komura Minoru Hasegawa Masanari Kodera Eiji Muroi Keita Fujikawa Mariko Seishima Hidehiro Yamada Ryo Yamada Shinichi Sato Kazuhiko Takehara Masataka Kuwana 《PloS one》2013,8(4)