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871.
872.
Md. Mehedi Hasan Shizuka Konishi Miyuu Tanaka Takeshi Izawa Jyoji Yamate Mitsuru Kuwamura 《Experimental Animals》2022,71(1):100
Coiled-coil domain containing 85c (Ccdc85c) is a causative gene for genetic hydrocephalus and subcortical heterotopia with frequent brain hemorrhage. In the present study, we examined the expression pattern of CCDC85C protein and intermediate filament proteins, such as nestin, vimentin, GFAP, and cytokeratin AE1/AE3, during lateral ventricle development in rats. CCDC85C was expressed in the neuroepithelial cells of the dorsal lateral ventricle wall, diminishing with development and almost disappearing at postnatal day 20. By immunoelectron microscopy, CCDC85C was localized in the cell-cell junction and apical membrane. The expression of nestin and vimentin was decreased in the wall of the lateral ventricle in manner similar to CCDC85C, but GFAP expression started immediately after birth and became stronger with age. Moreover, cytokeratin expression was found at postnatal day 13 and increased at postnatal day 20 in conjunction with the disappearance of CCDC85C expression. Taken together, CCDC85C is expressed in the cell-cell junctions lining the wall of the lateral ventricle and plays a role in neural development with other intermediate filaments in the embryonic and postnatal periods. Our chronological study will help to relate CCDC85C protein with intermediate filaments to elucidate the detailed role of CCDC85C protein during neurogenesis. 相似文献
873.
We investigated the frequency of courtship feeding (CF) in the Bull-headed Shrike (Lanius bucephalus) during the 1981–1982 breeding seasons. Because no CF was observed just prior to, during or just after copulation, CF is
not associated directly with copulation and does not function as a releaser for copulation. The absence of CF during the pair-formation
period of the early breeder and the high frequency of CF behavior in the cold season and in the critical breeding stages (egg-laying
and incubation stages) for females strongly suggests that the significance of CF in this species is not symbolic but substantial
at least in early breeders. We assign one of the causes of this CF to the early onset of breeding. 相似文献
874.
The facility consists of a 12 × 11.5 × 2.4 m high room containing six sets of exposure apparatus and the other equipment necessary to maintain a pathogen-free system. The apparatus sets produced 5 mT (rms), 0.5 mT, or a sham exposure. The apparatus was arranged in the room to minimize the fringing field of the 5 mT set at the sham position. Each set was 3.85 × 1.80 × 0.66 m in outside dimension, containing 24 cages in the magnetically homogeneous region. The apparatus was designed using Harvey's figure-eight-configuration and generated a horizontal sinusoidal alternating field. In order to save electric power, the coil of the apparatus constituted a 50 Hz LC resonance circuit with a condensor bank to which electric power was supplied to compensate losses. Magnetic flux density was kept constant by controlling the coil current. Although mild steel was used in the skeleton of the building, the fringing flux at the sham was as low as 0.1 to 1 μT. Stainless steel was used for ventilating ducts, racks for the cages, cage covers, feeder baskets, and watering nozzles. The homogeneity of the field was measured to be ± 10% in the animal residence area, and food and water consumption was found to be unaffected by the field. At 5 mT, the coil current was 370 A, and the hollow coil was cooled by a stream of 20°C water to prevent both heat and dew on the coil surface. Vibration and acoustic noise was prevented by fiber reinforced plastic framework of the coil. High harmonic distortion was not observed at the output terminal of the coil driver. The facility has operated without trouble for 2 years. © 1993 Wiley-Liss, Inc. 相似文献
875.
Daisuke Takaoka Akihiko Matsuo Mitsuru Nakayama Shûichi Hayashit 《Phytochemistry》1983,22(7):1653-1655
Three new diterpenoids of the verrucosane class were isolated as minor constituents of the methanol extract of the liverwort Mylia verrucosa and their structures shown to be 2β,9α,13β-trihydroxyverrucosane,9α-acetoxy-2β,13β-dihydroxyverrucosane and 2β,13β-dihydroxy-9-oxoverrucosane. 相似文献
876.
Akinori Hisatsune Mitsuru Kawasaki Yuji Mikami Yoichiro Isohama Kwang Chul Kim 《Biochemical and biophysical research communications》2009,388(4):677-381
MUC1 is a type I transmembrane glycoprotein aberrantly overexpressed in various cancer cells. It is thought to serve as a physical barrier from the extracellular environment and also as a receptor for various extracellular molecules. However, little is known about the fate of MUC1 during and after the interaction with these molecules. In the present study, we used anti-MUC1 antibody as an interacting molecule and investigated the cellular trafficking of MUC1. Our results showed that: (1) anti-MUC1 antibody was internalized only in MUC1 expressing cells and triggered internalization and down-regulation of MUC1; (2) the internalization of MUC1 by anti-MUC1 antibody required the cytoplasmic tail of MUC1 and was suppressed by inhibitors of Na+/H+ exchanger, and caveola/raft-dependent internalization, but not by an inhibitor of clathrin-dependent internalization. We conclude that antibody-induced internalization of MUC1 involves the macropinocytotic pathway. 相似文献
877.
Kazuki Yashiro Kengo Hanaya Mitsuru Shoji 《Bioscience, biotechnology, and biochemistry》2013,77(12):1926-1930
We have synthesized artepillin C, a diprenylated p-hydroxycinnamate originally isolated from Brazilian propolis and exhibiting antioxidant and antitumor activities, from 2,6-diallylphenol. Replacement of the terminal vinyl with 2,2-dimethylvinyl group by olefin cross-metathesis and subsequent transformation yielded 2,6-diprenyl-1,4-hydroquinone diacetate. Candida antarctica lipase B-catalyzed deacetylation in 2-propanol regioselectively removed the less hindered acetyl group to give 2,6-diprenyl-1,4-hydroquinone 1-monoacetate. After triflation of the liberated 4-hydroxy group, a three-carbon side chain was introduced by palladium-mediated alkenylation with methyl acrylate. Final hydrolysis of the esters furnished artepillin C. 相似文献
878.
879.
Kunihiko Ueda Takeaki Hanyuda Aiko Nakano Toshiaki Shiuchi Akihiro Seo Hirobumi Okubo Mitsuru Hotta 《Journal of plant research》1997,110(1):87-92
Podostemaceae are aquatic herbs and are famous for their anomalous vegetative morphology, occurring only in rapids. Because
of its peculiar morphology, there were no established theory nor accepted opinion on the phylogenetic position. Especially,
Cusset and Cusset (1988) proposed the new class, Podostemopsida beside the Magnollopsida and Liliopsida. We, therefore, consequences
extensive and detailled analyses using nucleotide sequences ofrbcL genes for two genera and three species of the family together with many representatives of the families of flowering plants
to determine the closest ally. The conclusion was that the Crassulaceae is a sister group to the Podostemaceae. 相似文献
880.