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111.
The insect cell-baculovirus expression vector system, widely used for glycoprotein production, is not ideal for pharmaceutical glycoprotein production due to the characteristics of the N-glycans in the expressed products. Insect cells lack several enzymes required for mammalian-type N-glycan synthesis and contain a specific N-acetylglucosaminidase that stunts the growth of chains and a core alpha-1,3-fucosyltransferase that yields potentially allergenic glycoforms. Current knowledge on N-glycan processing in lepidopteran insect cells is summarized, and strategies to develop better glycoprotein expression systems suitable for pharmaceutical glycoprotein production are discussed. 相似文献
112.
Energy value and digestibility of dietary oil containing mainly 1,3-diacylglycerol are similar to those of triacylglycerol 总被引:15,自引:7,他引:15
Diacylglycerol (DAG) is a component of various vegetable oils. Approximately 70% of the DAG in edible oils are in the configuration
of 1,3-DAG. We recently showed that long-term ingestion of dietary oil containing mainly 1,3-DAG reduces body fat accumulation
in humans as compared to triacylglycerol (TAG) oil with a similar fatty acid composition. As the first step to elucidate the
mechanism for this result, we examined the difference in the bioavailabilities of both oils by measuring food energy values
and digestibilities in rats. Energy values of the DAG oil and the TAG oil, measured by bomb calorimeter, were 38.9 and 39.6
kJ/g, respectively. Apparent digestibility expressed according to the formula: (absorbed) x (ingested)−1x100=(ingested—excreted in feces)x(ingested)−1x100 for the DAG oil and the TAG oil were 96.3±0.4 and 96.3±0.3% (mean±SEM), respectively. The similarity in the bioavailabilities
of both oils supports the hypothesis that the reduced fat accumulation by dietary DAG is caused by the different metabolic
fates after the absorption into the gastrointestinal epithelial cells. 相似文献
113.
Keiji Izumi Megumi Murakami Takenori Deguchi Arihiko Morita Noboru Tohge Tsutomu Minami 《Journal of the American Ceramic Society》1989,72(8):1465-1468
The stability and the coating characteristics of a variety of organozirconium compounds have been investigated to coat ZrO2 films on stainless steets for the improvement of heat resistance against oxidation. Zirconium tetraoctylate and zirconium tetrakis(acetylacetonate) were found to be more stable than zirconium alkoxides in an ambient atmosphere. The ZrO2 films from zirconium alkoxides became white and discontinuous when the thickness of the films exceeded about 200 Å (20 nm). On the other hand, transparent ZrO2 films were obtained from zirconium tetraoctylate and zirconium tetrakis(acetylacetonate). The IR spectra of the films showed that the heat treatment at 400°C for 5 min produced organic-free ZrO2 films. The heat resistance of stainless steel sheets against oxidation was improved by the ZrO2 coating, depending on the film thickness. 相似文献
114.
Fire Safety Performance of Japanese Traditional Wood/Soil Walls and Implications for the Restoration of Historic Buildings in Urban Districts 总被引:2,自引:0,他引:2
Yuji Hasemi Noboru Yasui Michitaka Akizuki Koichi Kinoshita Koichi Yamamoto Masatomo Yoshida Yoshihide Tamura Mariko Takeda 《Fire Technology》2002,38(4):391-402
Grass-root research activities to clarify fire safety performance of Japanese traditional wooden construction are introduced. The activities aim to resolve conflict between the restoration of historic buildings and the reduction of risk and hazard of urban fires. Among various activities, scope and results of fire resistance tests on traditional soil wall assemblies supported by timber frame are reported in detail. The test results indicate an encouraging prospect for the rational fire safety assessment of historic buildings and further development of fire-safe traditional constructions for the restoration of historic buildings and historic urban districts. 相似文献
115.
A reagent for the determination of phosphorus in sea water which contains Mo(VI) plus Mo(V) may be easily prepared by the reduction of Mo(VI) with metallic zinc in acid medium. This reagent is stable in the air for several months, and the development of the molybdenum blue colour is complete in 20 min at about 100°C; the colour is stable for at least a few months. The salt error is approximately 5 per cent with sea water of chlorinity 19 per milli. The interference due to either arsenate or silicate at their concentrations in sea water is negligible. 相似文献
116.
Regional allocation of public investment 总被引:1,自引:0,他引:1
Noboru Sakashita 《Papers in Regional Science》1967,19(1):161-182
Conclusion In the previous Sections, we have observed the following interesting properties of the optimum solution to this regional allocation problem.First, as indicated by assumptions (33) (34), and (35), public investment in one of the regions will be justified during some phase of the planning period, even if it is less productive than the private investment in the same region. The reason is that the central government can directly control the interregional flow of public fundsoutside the market mechanism and can concentrate its public investment on the region with greater growth potential.Second, as seen by equation (41), the value of (T–t
*), the length of the second phase of planning, is independent from the length of planning horizonT provided thatT>T–t
*. Then, the relative significance of the second phase will be less and less asT becomes larger and larger. This is one of the characteristics which have been observed in the dynamic programming problems with linear form. Therefore, ifT is very large, the public investment should be almost persistently concentrated to the second region, as far as there is no change in the values of relevant parameters.Third, the resultant optimum solution is very sensitive to the relative sizes of such parameters ass
i,
i
,
i
(i=1, 2), and . Then, if there is some slight change in them by means of social overhead investment, for instance, which was analyzed earlier in this paper, we may observe a drastic change of the optimum solution. Such being the case, it may be possible for us to utilize some combination of those two kinds of public investment policy in order to attain theoptimum optimorum in the set of feasible growth paths.The author is a postdoctoral fellow with the University of Pennsylvania. The present paper is a product of his research on the basic theory of regional growth which has been supported by a grant from the Ford Foundation. This support is gratefully acknowledged. He is indebted to Professors W. Isard, B. H. Stevens, and J. Kissin for their valuable comments on the earlier draft of this paper. Of course, the author alone is responsible for any remaining errors. 相似文献
117.
Tsuyoshi Ito Toshimasa Ohashi Hideyuki Hosokawa Tooru Kawasaki Motohiro Aizawa Yukie Ishizawa 《Journal of Nuclear Science and Technology》2016,53(6):831-841
The Pt coating (Pt-C) process has been developed to lower the recontamination by radioactive elements after chemical decontamination of piping surfaces. In this process, a layer of fine Pt nano particles is formed in an aqueous solution on the base metal of the piping following the chemical decontamination. In this study, we confirmed that the suppression effect by the Pt-C toward 60Co deposition on type 316 stainless steel using a 60Co deposition test under hydrogen water chemistry. Furthermore, we investigated the suppression mechanism of deposition of radioactive elements by a quantum molecular simulation. The deposition amounts of 60Co which were incorporated in oxides after 1000 h with and without the Pt-C process were about 90 and 10.2 Bq/cm2, respectively. The amount of 60Co deposition with Pt-C is about 10% that of non-coated specimens. The 60Co incorporation for the Pt-C specimen was suppressed by decreasing the formation of oxides. We considered this phenomenon using a quantum dynamics calculation and concluded that the Fe–O bonds in oxides were weakened by the effect of Pt and hydrogen radicals which were produced in the reaction between H2 and Pt, and then oxides were dissolved into the water. 相似文献
118.
Kyomoto M Moro T Konno T Takadama H Kawaguchi H Takatori Y Nakamura K Yamawaki N Ishihara K 《Journal of materials science. Materials in medicine》2007,18(9):1809-1815
Osteolysis caused by wear particles from polyethylene in the artificial hip joints is a serious issue. We have used photo-induced
radical graft polymerization to graft 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer onto the surface of cross-linked
polyethylene (CLPE-g-MPC) in order to reduce friction and wear at the bearing surface of the joint. The physical and mechanical properties of CLPE
and CLPE-g-MPC were not significantly different, expect that the friction coefficient of untreated CLPE cups was 0.0075, compared with
0.0009 for CLPE-g-MPC cup, an 88% reduction. After 3.0 × 106 cycles in the hip joint simulator test, we could not observe any wear of CLPE-g-MPC cups. We concluded that the advantage of photo-induced radical graft polymerization technique was that the grafted MPC
polymer gave a high lubricity only on the surface and has no effect on the bulk properties of the CLPE substrate. 相似文献
119.
Dietary effects of medium-chain triacylglycerols (MCT) and fucoxanthin (Fc) on abdominal fat weight were determined using KK-Ay obese mouse. Experimental diet contained MCT(0.9%), Fc (0.1%), or MCT (0.9%) +Fc (0.1%). The abdominal fat weight of mice fed with Fc was significantly lower than that of mice fed with MCT. Uncoupling protein 1 (UCP1), a key molecule for metabolic thermogenesis, was clearly expressed in the white adipose tissue (WAT) of mice fed Fc, but little expression in that of the mice fed MCT. The anti-obesity effect of Fc was increased by mixing Fc with MCT. This increase would be due to the increase in the absorption rate of Fc by MCT. 相似文献
120.
Murakawa K Fukunaga K Tanouchi M Hosokawa M Hossain Z Takahashi K 《Journal of oleo science》2007,56(4):179-188
Mushroom (Agaricus blazei Murill) extract has been reported to possess antitumor effects through immune activation. Here, we investigated the beneficial effects of combining A. blazei extract with marine phospholipids in comparison to A. blazei extract alone on myeloma sp2 tumor suppression when orally administrated. The experimental groups designed for sp2 tumor bearing BALB/c nu/nu mice were drinks of: (1)control; (2)1.0 mg/mL squid phospholipid liposome alone; (3)0.5 mg/mL A. blazei Murill water extract alone; (4)1.0 mg/mL squid phospholipid liposome with 0.5 mg/mL A. blazei Murill water extract in the form of those simple mixture; and (5)1.0 mg/mL squid phospholipid liposome with 0.5 mg/mL A. blazei Murill water extract partially encapsulated. Orally administrated volumes amounted to approximately 5 mL per day per mouse for all groups. A. blazei Murill water extract alone and squid phospholipid alone served groups show moderate tumor suppression with total administrations of approximately 105 mg/mouse for squid phospholipid through out the experimental term. When both A. blazei Murill water extract and squid phospholipid were administrated simultaneously in a simple mixture form, promotional effect on cancer tumor suppression was observed. And when A. blazei Murill water extract was partially encapsulated in the squid phospholipid liposomes with total administrations being 105 mg/mouse for squid phospholipid, effect on cancer tumor suppression was more pronounced. Though there was no statistically significant difference in tumor sizes between the simple mixture form administrated group i.e. group (4) and the partially encapsulated form administrated group i.e. group (5), the tumor vanished mouse was seen in the partially encapsulated form administrated group. Thus it was concluded that combinational administration of the A. blazei Murill water extract and the marine phospholipid may be useful in myeloma sp2 therapy. 相似文献