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91.
Phosphoenolpyruvate (PEP) is a phosphorylated glycolytic intermediate that can penetrate the RBC membrane and be metabolized to 2,3-DPG and ATP. In this study, we evaluated the effects of PEP treatment on canine red blood cells (RBCs) cryopreserved with 12.5% (w/v) HES. RBCs were incubated for 30, 60, and 90 min at 37 degrees C with PEP solution containing 60 mM mannitol, 30 mM sodium chloride, 25 mM glucose, 1 mM adenine and 50 mM PEP (340 m osm/kg), pH 6.0 and then cryopreserved in liquid nitrogen with 12.5% (w/v) HES for 2 weeks. 2,3-DPG and saline stabilities of the PEP treated groups were increased and osmotic fragility indices were significantly decreased compared to the untreated control group. There were no differences in 2,3-DPG levels within the PEP treated groups with different PEP incubation times. These results suggest that PEP treatment may be beneficial for the cryopreservation of canine RBCs with HES. 相似文献
92.
In this Letter, we discuss the generation of magnetic field from cosmological perturbations. We consider the evolution of three component plasma (electron, proton, and photon) evaluating the collision term between electrons and photons up to the second order. The collision term is shown to induce electric current, which then generates magnetic field. There are three contributions, two of which can be evaluated from the first-order quantities, while the other one is fluid vorticity, which is purely second order. We estimate the magnitudes of the former contributions and show that the amplitude of the produced magnetic field is about approximately 10(-19) G at 10 Mpc comoving scale at the decoupling. Compared to astrophysical and inflationary mechanisms for seed-field generation, our study suffers from much less ambiguities concerning unknown physics and/or processes. 相似文献
93.
Effect of moisture on impact toughness of sugar-coated tablets manufactured by the dusting method 总被引:1,自引:0,他引:1
The purpose of this study was to clarify the effect of moisture on the impact toughness of sugar-coated tablets manufactured by the dusting method. We demonstrated that moisture plays an important role in the impact toughness of sugar-coated tablets. Moisturizing the sugar-coating layer resulted in enhancement of impact toughness of sugar-coated tablets, while reducing moisture in the sugar-coating layer resulted in weakening of the impact toughness. This was due to the characteristics of sucrose, the main ingredient of the sugar-coating layer, which is a soft and non-fragile material at high moisture levels, but hard and fragile at low moisture levels. We also demonstrated that friability as an indicator of impact toughness changed with time, and friability should be measured at 14 d after manufacture. This is due to moisture movement from outer sugar-coating layer into the inner sugar-coated tablets. Incorporating microcrystalline cellulose (MCC) in the subcoating layer resulted in sugar-coating layers with high resistance against impact even though moisture content of sugar-coated tablets was low. We confirmed the high impact toughness of the sugar-coated tablets with MCC whose moisture content was low from the results of both free fall and friability tests. We suggest that the dusting method using dusting powder containing MCC is a useful method for the production of sugar-coated tablets containing moisture sensitive drugs. 相似文献
94.
Ohno H Iwasaki H Eguchi T Tanaka T 《Chemical communications (Cambridge, England)》2004,(19):2228-2229
Intramolecular arylation of aryl radicals was mediated by SmI(2)/HMPA in the presence of i-PrOH to give spirocycles and/or reduced cine-cyclised products, while the reaction in the absence of i-PrOH gave the rearomatised fused rings. 相似文献
95.
96.
97.
Components and isolated points of the topological space of composition operators onH
in the uniform operator topology are characterized. Compact differences of two composition operators are also characterized. With the aid of these results, we show that a component inC(H
) is not in general the set of all composition operators that differ from the given one by a compact operator.Supported by the Grant-in-Aid for Scientific Research (C), the Ministory of Education, Science and Culture, No. 09640218, and the Nippon Institute of Technology No. 111Supported by the Japan Society for the Promotion of Science 相似文献
98.
Xue QZ Xue QK Kuwano S Sadowski JT Kelly KF Sakurai T Ohno T 《Physical review letters》2000,84(17):4015
99.
Akiko Ohno Nana Kawasaki Kiyoshi Fukuhara Haruhiro Okuda Teruhide Yamaguchi 《Magnetic resonance in chemistry : MRC》2010,48(2):168-172
Complete NMR analysis of oxytocin (OXT) in phosphate buffer was elucidated by one‐dimensional (1D)‐ and two‐dimensional (2D)‐NMR techniques, which involve the assignment of peptide amide NH protons and carbamoyl NH2 protons. The 1H? 15N correlation of seven amide NH protons and three carbamoyl NH2 protons were also shown by HSQC NMR of OXT without 15N enrichment. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
100.
On the basis of the theory developed in a previous paper (Part I), the angle and speed distributions of D2 molecules desorbing thermally from the Ni(111) surface are numerically calculated in the present paper (Part II). The dynamical motion of the activated complex of the recombinative desorption process is calculated by using a model potential surface, which involves a few parameters introduced to describe the necessary features of the potential surface at the transition state. Numerical calculations are carried out, and the results show that the present dynamical theory reproduces very well a variety of the characteristic features of the experimental results, e.g., sharply focused angular distribution, mean translational energy lower than 2k
B
T at grazing angle, and the non-Maxwellian profile of the TOF distribution. 相似文献