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111.
Munekawa K Tamada Y Iijima N Hayashi S Ishihara A Inoue K Tanaka M Ibata Y 《Experimental neurology》2000,166(1):44-51
The development of astroglial cells and the effect of the retinohypothalamic tract on it were studied by vimentin and glial fibrillary acidic protein (GFAP) immunocytochemistry in the suprachiasmatic nucleus (SCN) of the rat. At the embryonic stage, vimentin-immunoreactive (VIM-IR) radial glia, precursors of astrocytes, were dominant. However, their filaments vanished in the first few postnatal days. Instead of VIM-IR glial filaments, GFAP-immunoreactive (GFAP-IR) astrocytes appeared at E20 and grew rapidly from the P3 stage. GFAP immunoreactivity in the ventrolateral portion of the SCN (VLSCN) was measured using a computer-assisted image analyzing system. In normal rats, GFAP immunoreactivity showed a stepwise pattern with two slopes at P3-P4 and P20-P25. Bilaterally eye-enucleated rats operated on the day of birth showed lower GFAP immunoreactivity than normal rats and the GFAP immunoreactivity did not increase between P20 and P25 when GFAP-IR glial processes rapidly expand. Electron microscopic investigation at P50 (adult stage) revealed that neurons in the VLSCN had often direct apposition without astroglial processes and the frequency of this finding was significantly higher in eye-enucleated rats than in the control rats. These findings strongly suggest that the postnatal development of astroglial elements, particularly the expansion of GFAP-IR processes in the SCN, is regulated by retinohypothalamic projection. 相似文献
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Toshiaki Watanabe Takamitsu Kanazawa Yoshihiro Kazama Junichiro Tanaka Toshiaki Tanaka Soichiro Ishihara Hirokazu Nagawa 《Journal of clinical oncology》2005,23(35):9031-2; author reply 9032-3
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Sachiro Kakinoki Ji-Hun Seo Yuuki Inoue Kazuhiko Ishihara Nobuhiko Yui 《Journal of biomaterials science. Polymer edition》2013,24(11):1320-1332
Adhesion behaviors of human umbilical vein endothelial cells (HUVECs) are interestingly affected by the mobility of hydrophilic chains on the material surfaces. Surfaces with different molecular mobilities were prepared using ABA-type block copolymers consisting polyrotaxane (PRX) or poly(ethylene glycol) (PEG) central block (A block), and amphiphilic anchoring B blocks of poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (PMB). Two different molecular mobilities of the PRX chains were designed by using normal α-cyclodextrin (α-CD) or α-CD whose hydroxyl groups were converted to methoxy groups in a given ratio to improve its molecular mobility (PRX–PMB and OMe-PRX–PMB). The surface mobility of these materials was assessed as the mobility factor (Mf), which is measured by quartz crystal microbalance with dissipation monitoring system. HUVECs adhered on OMe-PRX–PMB surface much more than PRX–PMB and PMB-block–PEG–block-PMB (PEG–PMB) surfaces. These different HUVEC adhesions were correlated with the density of cell-binding site of adsorbed fibronectin. In addition, the alignment of the actin cytoskeleton of adhered HUVECs was strongly suppressed on the PEG–PMB, PRX–PMB, and OMe-PRX–PMB in response to the increased Mf value. Remarkably, the HUVECs adhered on the OMe-PRX–PMB surface with much less actin organization. We concluded that not only the cell adhesion but also the cellular function are regulated by the molecular mobility of the outmost material surfaces. 相似文献
115.
Motoyasu Kobayashi Kazuhiko Ishihara 《Journal of biomaterials science. Polymer edition》2014,25(14-15):1673-1686
The swollen brush structures of polycation and zwitterionic polymer brushes, such as poly(2-methacryloyloxyethyltrimethylammonium chloride) (PMTAC), poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), and poly[3-(N-2-methacryloyloxyethyl-N,N-dimethyl)ammonatopropanesulfonate] (PMAPS), in aqueous solutions of various ionic strengths were characterized by neutron reflectivity (NR) measurements. A series of the polyelectrolyte brushes were prepared by surface-initiated controlled radical polymerization on silicon substrates. A high-graft-density PMTAC brush in salt-free water (D2O) adopted a two-region step-like structure consisting of a shrunk region near the Si substrate surface and a diffuse brush region with a relatively stretched chain structure at the solution interface. The diffuse region of PMTAC was reduced with increase in salt (NaCl) concentration. The PMAPS brush in D2O formed a collapsed structure due to the strong molecular interaction between betaine groups, while significant increase in the swollen thickness was observed in salt aqueous solution. In contrast, no change was observed in the depth profile of the swollen PMPC brush in D2O with various salt concentrations. The unique solution behaviors of zwitterionic polymer brushes were described. 相似文献
116.
Results of a 36‐year surveillance program for ulcerative colitis‐associated neoplasia in the Japanese population
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Junko Kishikawa Keisuke Hata Shinsuke Kazama Hiroyuki Anzai Takahide Shinagawa Koji Murono Manabu Kaneko Kazuhito Sasaki Koji Yasuda Kensuke Otani Takeshi Nishikawa Toshiaki Tanaka Tomomichi Kiyomatsu Kazushige Kawai Hiroaki Nozawa Soichiro Ishihara Teppei Morikawa Masashi Fukayama Toshiaki Watanabe 《Digestive endoscopy》2018,30(2):236-244
117.
Takeshi Yamashina Ryu Ishihara Noriya Uedo Kengo Nagai Fumi Matsui Natsuko Kawada Takashi Oota Hiromitsu Kanzaki Masao Hanafusa Sachiko Yamamoto Noboru Hanaoka Yoji Takeuchi Koji Higashino Hiroyasu Iishi 《Digestive endoscopy》2012,24(4):220-225
Background and Aim: Limited data are available regarding the use of endoscopic submucosal dissection (ESD) for superficial esophageal cancers ≥50 mm in diameter. The aim of the present study was to investigate the safety and success of ESD for superficial esophageal cancers ≥50 mm. Methods: A total of 39 patients with superficial esophageal squamous cell carcinoma ≥50 mm were treated with ESD at Osaka Medical Center for Cancer and Cardiovascular Diseases between January 2004 and April 2011, and were analyzed in a retrospective study. Results: En bloc resection was achieved in all patients. One mediastinal emphysema without perforation occurred during the procedure. Stricture developed in 11 of 39 patients, requiring a median of five endoscopic balloon dilatation procedures. Thirty‐three clinical epithelial or lamina propria mucosal cancers were treated by ESD with curative intent, of which invasion into the muscularis mucosa or deeper was detected in seven and lymphovascular involvement in three. The en bloc resection rate was 100% with a tumor‐free margin achieved in 92% of lesions. The curative resection and complication rates during ESD were 70% and 2.5%, respectively. Conclusion: ESD achieved a high en bloc resection rate of 92% with a tumor‐free margin. Curative resection rate of ESD in patients with clinical epithelial or lamina propria mucosal cancers was not low at 70%. However, the risk of stricture must be taken into account when considering the use of ESD in lesions ≥50 mm. 相似文献
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