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排序方式: 共有1006条查询结果,搜索用时 281 毫秒
101.
Makoto Sakuragi Saki Tsuzuki Sei Obuse Akira Wada Kenji Matoba Izumi Kubo Yoshihiro Ito 《Materials science & engineering. C, Materials for biological applications》2010,30(2):316-322
A novel photoreactive polymer containing sulfobetaine polar groups was prepared by copolymerization of two kinds of methacrylic acids with sulfobetaine and azidoaniline. The polymer was photoimmobilized on polyester and polystyrene surfaces. Its effects on surface modification were investigated from its interactions with water, proteins and cells. Polymer immobilization altered both of the plain surfaces to becoming hydrophilic in a similar range of static contact angles (12.5 ± 1.6° on polyester and 14.7 ± 2.2° on polystyrene). This suggests that the surfaces were covered with sulfobetaine polar groups. Micropattern immobilization was carried out on both polymers using a photomask. The formed pattern was identical to the photomask, showing that the polymer was formed in response to ultraviolet irradiation. Measurements using atomic force microscopy showed that the polymer was formed at a thickness of 550 nm, demonstrating that the polymer was cross-linked with itself and with the substrate molecules. Measurements using time-of-flight secondary ion mass spectrometry detected an abundance of sulfur-containing ions in the patterned polymer, confirming that sulfobetaine had been immobilized. Protein adsorption and mammalian cell adhesiveness were reduced markedly on the immobilized regions. The reduction of cell adhesiveness was concentration-dependent for the immobilized polymer on polyester surfaces. In conclusion, a novel sulfobetaine-containing polymer was immobilized photoreactively on conventional polymer surfaces and significantly reduced interactions with proteins and mammalian cells. 相似文献
102.
M Izumi S Ohwada S Kawate N Tokizawa T Anzai A Sasaki Y Morishita 《Canadian Metallurgical Quarterly》1997,24(10):1321-1325
A 50-year-old man with moderately differentiated adenocarcinoma of the rectum was operated upon following preoperative administration of FT suppository. Digital examination, colonoscopy, and barium enema showed an elevated lesion with central ulcer of the rectum. Microscopically, the biopsy specimen demonstrated moderately differentiated adenocarcinoma. FT suppository (1,500 mg/day for 52 days, total 78 g) was administered on an outpatient basis. Rectal amputation including lymph node dissection was performed. The tumor markedly reduced in size and changed into a small ulcer in the resected specimen. Microscopically, the tumor degenerated and changed into xanthogranulomatous tissue with foamy histiocytes. Only two tubules of degenerated adenocarcinoma remained. FT suppository for rectal cancer is considered to be safe and effective. 相似文献
103.
104.
K Hashimoto C Azuma Y Tokugawa T Nobunaga TA Aki Y Matsui T Yanagida H Izumi F Saji Y Murata 《Canadian Metallurgical Quarterly》1997,28(7):862-865
An unusual clinical presentation of a patient with neuronal intestinal dysplasia is presented. A 46-year-old male noted a palpable mass in the right lower quadrant of his abdomen for two months. A computed axial tomographic scan showed a thickened wall of the cecum with a tumor-like appearance. The excised specimen consisted of a mass caused by the thickened, edematous wall of the dilated cecum and appendix. The wall of the cecum and appendix measured up to 2.5 and 0.8 cm, respectively, in thickness. Microscopic studies showed extensive hyperplasia and hypertrophy of the ganglia and nerve plexuses and hypertrophy of the muscularis propria, consistent with neuronal intestinal dysplasia. 相似文献
105.
106.
The environmental effects on Co3Ti polycrystals doped with boron, carbon and beryllium were investigated by tensile testing in air at 293 to 1173 K and the results were compared with those tested in vacuum. The yield stresses of the alloys observed were independent of the test environment. The elongation and ultimate tensile strength of the alloys observed were strongly dependent on the test environment and also the test temperatures. Ductility losses were found for the samples which were tested in air at temperatures below 473 K. The losses were accompanied by a change in fracture mode from transgranular to intergranular. It was suggested that this embrittlement was due to the hydrogen absorbed from air. Neither species boron, carbon nor beryllium were observed in this work to affect the environmental effects on the ductility behaviour of Co3Ti alloys. 相似文献
107.
Taeko Izumi Satoshi Aratani 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1994,59(4):403-408
Enantioselective hydrolysis of racemic acetate or butyrates of 1-hydroxy [3](1,1′) ferrocenophane and endo-1-hydroxy [4](1,2) ferrocenophane using lipases, pig liver esterase and horse liver esterase resulted in the formation of (R)-alcohols and (S)-esters. 相似文献
108.
A high-current oxygen implanter which has an acceleration energy of 200 keV and a beam current of 100 mA has been developed. This implanter has been used to form SIMOX wafers, on which p- and n-channel MOSFETs have been fabricated on a trial basis. Good electrical characteristics have been achieved with these MOSFETs. It has been shown that a 100 mA-class high-current oxygen implanter can promote SIMOX technology in a practical way. 相似文献
109.
Dr. Masayuki Izumi Akihisa Otsuki Mika Nishihara Dr. Ryo Okamoto Prof. Dr. Yasuhiro Kajihara 《Chembiochem : a European journal of chemical biology》2014,15(17):2503-2507
As a basis for the development of an artificial carbohydrate‐binding lectin, we chemically synthesized a domain of siglec‐7, a well‐characterized sialic‐acid‐binding lectin. The full polypeptide (127 amino acids) was constructed by sequential native chemical ligation (NCL) of five peptide segments. Because of poor cysteine availability for NCL, cysteine residues were introduced at suitable ligation sites; these cysteine residues were alkylated in order to mimic native glutamine or asparagine residues, or converted to an alanine residue by desulfurization after NCL. After folding the full‐length polypeptide, the sialic‐acid‐binding activity of the synthetic siglec‐7 was clearly demonstrated by STD NMR and ELISA experiments. We succeeded in the synthesis of siglec‐7 by installing three extra cysteine residues with side‐chain modifications and found that these modifications did not affect the binding activity. 相似文献
110.
Gonzalo Recio-Sánchez Kyoko Namura Motofumi Suzuki Raúl J Martín-Palma 《Nanoscale research letters》2014,9(1):487
In the present work, the photo-acoustic emission from nanostructured copper/porous silicon hybrid systems was studied. Copper nanoparticles were grown by photo-assisted electroless deposition on crystalline silicon and nanostructured porous silicon (nanoPS). Both the optical and photo-acoustic responses from these systems were determined. The experimental results show a remarkable increase in the photo-acoustic intensity when copper nanoparticles are incorporated to the porous structure. The results thus suggest that the Cu/nanoPS hybrid systems are suitable candidates for several applications in the field of thermoplasmonics, including the development of sound-emitting devices of great efficiency. 相似文献