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81.
The oligosaccharide of glycoproteins in the fission yeast Schizosaccharomyces pombe is unique in containing galactose. We isolated four mutants that had reduced amounts of galactose residues on their cell surface glycoproteins by fluorescence-activated cell sorter. The isolated four recessive mutants, gmd1 to gmd4, showed a defect in glycosylation of acid phosphatase, a cell surface glycoprotein. In gmd3 mutant cells, the amounts of both mannose and galactose residues were decreased on the cell surface galactomannoproteins, suggesting an underglycosylation of galactomannoproteins. The gmd3(+) gene encodes a protein that has significant similarity with Saccharomyces cerevisiae Alg11p and is likely to be involved in N-linked core oligosaccharide synthesis. ALG11 suppressed the gmd3 mutation, indicating that gmd3(+) gene is a functional homologue of the ALG11 gene. We therefore designated gmd3(+) as alg11(+). 相似文献
82.
83.
Min‐Jung Bae Takeshi Ishii Kanako Minoda Yukiko Kawada Tatsuya Ichikawa Taiki Mori Miya Kamihira Tsutomu Nakayama 《Molecular nutrition & food research》2009,53(6):709-715
(–)‐Epigallocatechin gallate (EGCg) is the major component of green tea and is known to show strong biological activity, although it can be easily oxidized under physiological conditions. In this study, we indicate that EGCg is stable in human serum and that human serum albumin (HSA) stabilizes EGCg under aerobic condition. Although EGCg is usually decomposed within 1 h in aqueous solution at neutral pH, EGCg in serum and phosphate buffer (pH 7.4) containing HSA was stable over 1 h, even at neutral and slightly alkaline pH. Under these conditions, EGCg binds to HSA non‐covalently. The sulfhydryl group acts as an antioxidant for EGCg oxidation. Incubation of EGCg with HSA is accompanied by the oxidation of a free sulfhydryl group in HSA. These results suggest that the antioxidant property and the binding capacity of HSA contribute to the stabilization of EGCg in human serum. 相似文献
84.
Matsukawa T. Yoshida Y. Kanke M. Yamashita K. Shimada R. Nakayama T. 《Energy Conversion, IEEE Transaction on》1987,(2):262-268
A 215 MVA flywheel motor-generator is used for the toroidal field coil power supply system of the energy breakeven plasma testing facility, JT-60, which started operations in April, 1985 at JAPAN ATOMIC ENERGY RESEARCH INSTITUTE. This paper describes an outline of the flywheel motor-generator and discusses the determination of the Xd' value which affects the voltage regulation characteristic of the motor-generator and the twenty-four pulse rectifier circuit, the compensation effect of AVR for the voltage regulation characteristic, the temperature rise and stress of the flywheel which is the largest one in the world and the torsional vibration caused by a thyristor starter, together with the results of field tests. 相似文献
85.
86.
J Nakayama K Hamano Y Shimakura N Iwasaki C Nakahara N Imoto K Kobayashi T Arinami H Hamaguchi 《Canadian Metallurgical Quarterly》1997,28(6):335-337
BACKGROUND: Most adult anatomical texts state that the deep inguinal ring is situated midway between the anterior superior iliac spine and the pubic tubercle. The aim of this study was to determine if this was true in prepubescent children. METHODS: A total of 107 inguinal ligaments and canals were measured during inguinal operations in 80 children (68 boys, age range 1-118 months). RESULTS: The length of the inguinal ligament increased from a median of 4.3 cm (range 3.6-6.8) at less than 1 year of age to 7.5 cm (range 6.7-10.1) at over 4 years of age. The internal ring was situated medial to the midpoint of the inguinal ligament throughout childhood. The ratio of internal ring to public tubercle over inguinal ligament length was 42% (range 27-58) at less than 2 years; and 34% (range 25-46) at over 4 years. The inguinal canal remained short (median 1 cm (range 0.7-1.1) at less than 2 years, and median 1.1 cm (range 0.7-2.3) at over 4 years) suggesting that growth of the inguinal region in this age group occurs outside the canal. CONCLUSIONS: These results have implications for the siting of incisions, and question the necessity of opening the inguinal canal in children. 相似文献
87.
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89.
Tomoyuki Kawase Kazuhiro Okuda Hiroyuki Kogami Hitoshi Nakayama Masaki Nagata Hiromasa Yoshie 《Journal of materials science. Materials in medicine》2010,21(2):731-739
Our animal implantation studies have demonstrated that, after osteogenic processing, cultured human periosteal sheets form
osteoid tissue ectopically without the aid of conventional scaffolding materials. To improve the osteogenic activity of these
periosteal sheets, we have tested the effects of including a scaffold made of salmon collagen-coated ePTFE mesh. Periosteal
sheets were produced with minimal manipulation without enzymatic digestion. Outgrown cells penetrated into the coated mesh
fiber networks to form complex multicellular layers and increased expression of alkaline phosphatase activity in response
to the osteoinduction. In vitro mineralization was notably enhanced in the original tissue segment regions, but numerous micro-mineral
deposits were also formed on the coated-fiber networks. When implanted subcutaneously into nude mice, periosteal sheets efficiently
form osteoid around the mineral deposits. These findings suggest that the intricate three-dimensional mesh composed of collagen-coated
fibers substantially augmented the osteogenic activity of human periosteal sheets both in vitro and in vivo. 相似文献
90.
Toru Ikegami Tomotake Morita Shunichi Nakayama Hideyuki Negishi Dai Kitamoto Keiji Sakaki Yasunori Oumi Tsuneji Sano Kenji Haraya Hiroshi Yanagishita 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(8):1172-1177
BACKGROUND: Pervaporation employing ethanol‐permselective silicalite membranes as an alternative to distillation is a promising approach for refining low‐concentration bioethanol solutions. However, to make the separation process practicable, it is extremely important to avoid the problems caused by the adsorption of succinate on the membrane during the separation process. In this work, the pervaporation of an ethanol fermentation broth without succinate was investigated, as well as the influence of several fermentation broth nutrient components. RESULTS: Candida krusei IA‐1 produces an extremely low level of succinate. The decrease in permeate ethanol concentration through a silicone rubber‐coated silicalite membrane during the separation of low‐succinate C. krusei IA‐1 fermentation broth was significantly improved when compared with that obtained using Saccharomyces cerevisiae broth. By treating the fermentation broth with activated carbon, bioethanol was concentrated as efficiently as with binary mixtures of ethanol/water. The total flux was improved upto 56% of that obtained from the separation of binary mixtures, compared with 43% before the addition of activated carbon. Nutrients such as peptone, yeast extract and corn steep liquor had a negative effect on pervaporation, but this response was distinct from that caused by succinate. CONCLUSION: For consistent separation of bioethanol from C. krusei IA‐1 fermentation broth by pervaporation, it is useful to treat the low nutrient broth with activated carbon. To further improve pervaporation performance, it will be necessary to suppress the accumulation of glycerol. Copyright © 2009 Society of Chemical Industry 相似文献