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381.
The antioxidative activity of the extracts of loquat fruits, Eriobotrya japonica Lindley was examined. Loquat fruit was separated into three parts (peel, flesh and seed), and each part was extracted with either water or ethanol. The extracts were then assessed for their free radical scavenging ability and effects on the oxidation of human low density lipoprotein (LDL) in vitro. Results in this study show that the ethanol extracts of all three loquat parts and the water extract of the peels exhibited a strong ability to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. Among extracts of different loquat parts, the ethanol extract of loquat seeds was the most potent one. The ethanol extract of the seed was also effective in suppressing the oxidation of linoleic acid which was demonstrated by a slow discoloration of β-carotene/linoleic acid conjugation system. The ethanol extract of loquat seeds as compared to other extracts could also suppress significantly the 2,2′-azobis(4-methoxy-2,4-dimethylvaleronitrile) (MeO-AMVN)-induced LDL oxidation. When the content of total polyphenolic compounds in different loquat parts (peel, flesh and seed) was examined, a significantly higher level of total polyphenols was found in the seed than the peels and flesh. Using reverse-phase HPLC-ESI EM analysis, significant levels of polyphenolic compounds such as chlorogenic acid, cyanidine glucoside, epicatechin, epigalocatechin gallate and procyanidin B2 in the ethanol extract of different loquat parts were identified and quantified. The latter two compounds were found mainly in the ethanol extract of loquat seeds, but not in peels and flesh. Therefore, it is suggested that the high ability to scavenge free radicals and suppress the LDL oxidation exerted by the ethanol extract of loquat seeds was at least in part due to the high content of polyphenolic compounds in the seeds. 相似文献
382.
An ionizable thin film with gradient network size in direction of thickness was prepared using 10-undecenoic acid(UA) by plasma polymerization. Gradient structure in the network size was estimated by values of relative diffusion coefficient of ferocian ions through the film. The obtained film was found to show chemomechanical behavior. The film bent in alkaline solution due to anisotropic swelling in direction of thickness and recovered to the original shape in acid solution. 相似文献
383.
A zero‐bias‐current self‐sensing active magnetic bearing is proposed. One degree‐of‐freedom (DOF) of the rotor is controlled by a pair of electromagnets which are alternatively energized by the proposed circuit. The rotor position of the one DOF is measured by using both electromagnets: the nonenergized electromagnet also contributes to the position sensing. The proposed method gives good linearity in the position estimation. The controller of the magnetic levitation consists of a digital signal processor, DSP, which compensates the nonlinearity of the magnetic force and achieves good damping. In the experiment, the rotor can run at 45,000 min‐1. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(2): 69–76, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20616 相似文献
384.
Y Kasamatsu M Osada K Ashida K Azukari K Yoshioka A Ohsawa 《Canadian Metallurgical Quarterly》1998,37(2):169-173
OBJECTIVE: To investigate the role of human parvovirus B19 (Parvo B19), cytomegalovirus (CMV) and human papilloma virus (HPV) viruses in the aetiopathogenesis of spontaneous abortions. STUDY DESIGN: Abortion material from 102 cases of women with spontaneous abortions were analysed for the presence of Parvo B19, CMV and HPV DNA using the polymerase chain reaction (PCR) technique. Serological assays were used for the detection of specific IgM and IgG antibodies against Parvo B19 virus and CMV in the maternal sera. RESULTS: Parvo B19 virus genome was detected in two cases of spontaneous abortion, by PCR amplification, while CMV and HPV genomes were not observed. Serological markers were indicative for Parvo B19 virus and CMV infection in ten and four cases, respectively. CONCLUSIONS: PCR is a useful method for investigating the viral contribution to the aetiopathogenesis of spontaneous abortions and for detecting the viral genome in the abortion material. This study of 102 cases of spontaneous abortion does not implicate CMV and HPV in the aetiopathogenesis of spontaneous abortion, although it indicates a possible abortional role for Parvo B19 virus. 相似文献
385.
Oishi K Nakao N Kosako K Yamakawa H Nakashima H Kawai M Yashima H Sanami T Numajiri M Shibata T Hirayama H Nakamura T 《Radiation protection dosimetry》2005,115(1-4):623-629
Precise estimation of induced activities in concrete shields for high-energy accelerator facilities is one of the most important issues that need to be solved, not only for the reduction of exposure for workers, but also for the reduction of radioactive wastes. Irradiation experiments have been performed by using the 500 MeV Neutron Spallation Source Facility in KEK. The large concrete assembly was placed in the direction of 0 degrees to the beamline. Two kinds of samples were placed at several positions in the assembly. The irradiation period was about 1 week and induced activities in the samples were measured until approximately 1.5 y after irradiation. From the comparison between the experiment and the available Monte Carlo calculation code system, good agreement was obtained for 24Na, 47Sc, 47Ca and 54Mn within a factor 2; however, large discrepancies were observed for some other nuclides. 相似文献
386.
Lee HS Ban S Sanami T Takahashi K Sato T Shin K Chung C 《Radiation protection dosimetry》2005,116(1-4 PT 2):653-657
A study of differential photo-neutron yields by irradiation with 2 GeV electrons has been carried out. In this extension of a previous study in which measurements were made at an angle of 90 degrees relative to incident electrons, the differential photo-neutron yield was obtained at two other angles, 48 degrees and 140 degrees, to study its angular characteristics. Photo-neutron spectra were measured using a pulsed beam time-of-flight method and a BC418 plastic scintillator. The reliable range of neutron energy measurement was 8-250 MeV. The neutron spectra were measured for 10 Xo-thick Cu, Sn, W and Pb targets. The angular distribution characteristics, together with the previous results for 90 degrees, are presented in the study. The experimental results are compared with Monte Carlo calculation results. The yields predicted by MCNPX 2.5 tend to underestimate the measured ones. The same trend holds for the comparison results using the EGS4 and PICA3 codes. 相似文献
387.
Matsui R Hasegawa M Ishida M Ebata T Namiki N Sugibayashi K 《Drug development and industrial pharmacy》2005,31(8):729-738
In vitro permeation of lidocaine (lidocaine base, LID) through excised rat skin was investigated using several LID-suspended oily formulations. The first skin permeation of LID from an LID-suspended oily solution such as liquid paraffin (LP), isopropyl myristate (IPM), polyoxyethylene (2) oleylether (BO-2), and diethyl sebacate (DES) was evaluated and compared with that from polyethylene glycol 400 (PEG400) solution, a hydrophilic base. The obtained permeation rate of LID, Japp, from PEG400, LP, IPM, BO-2, and DES was in the order of DES>BO-2=IPM>LP>PEG400, and increased with LID solubility in the oily solvents, although LID crystals were dispersed in all solvents. Subsequently, oily formulations that consisted of different ratios of the first oily solvent (IPM, BO-2, or DES) (each 0-20%), the second oily solvent (LP) and an oily mixture of microcrystalline wax/white petrolatum/paraffin (1/5/4) were evaluated. BO-2 groups at a concentration of 5% and 10% had the highest Japp among the oily formulations, although a higher BO-2 resulted in lower skin permeation. In addition, pretreatment with BO-2 increased the skin permeation of LID. These results suggest that the penetration enhancing effect by the system may be related to the skin penetration of BO-2 itself. Finally, mathematical analysis was done to evaluate the effect of BO-2, and it was shown that BO-2 improved the LID solubility in stratum corneum lipids to efficiently enhance the LID permeation through skin. 相似文献
388.
Sasaki K Tatsuno T Nakamura M Anazawa A Imazawa T Utsunomiya O Terasawa S Osada H Kaneko M Toyoda M 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2001,42(4):269-272
Method-performance studies were conducted for the notified revised analytical method of inabenfide in unpolished rice. Six laboratories analyzed unpolished rice spiked with 0.05 microgram/g of inabenfide in replicate. Mean recovery from rice was 85.0%. Repeatability relative standard deviation value was 4.2% and reproducibility relative standard deviation value was 8.1%. The detection limits were 0.002-0.01 microgram/g. 相似文献
389.
A treatment policy must be established for primary mediastinal seminoma. We have treated five patients with this entity during 18 years. All our patients presented with a bulky mass as is usual for this disease. Our first patient was treated surgically and then with radiation, but developed recurrences and died 11 years after the initial diagnosis. Three subsequent patients, one with multiple lymph node metastases, were treated with radiation followed by cisplatin. Our most recent patient received two courses of adriamycin-reinforced PVB, and then radiation for consolidation, followed by another course of chemotherapy. For these five patients, the 5- and 10-year survival rates were both 100%. A review of the literature emphasized the fact that either radiation or surgery has recently been replaced by chemotherapy as the front-line treatment of this rare tumor in light of a better response to the latter form of treatment. We fully agree with this policy. Based on the favorable long-term results of our patients we conclude that chemo-radiotherapy can cure primary mediastinal seminoma, even in its extended form, without surgery. An initial three courses of cisplatin-based chemotherapy like adriamycin-reinforced PVB or BEP should be followed by radiation of up to 4,000 cGy for consolidation. Surgery may play a limited role for tumors that are small at presentation, or for any possible viable residue seen on roentgenograms following chemo-radiotherapy. 相似文献
390.