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41.
α-Tocopherol wss reacted with an alkylperoxyl radical at 37°C in ethanol. 2,2′-Azobis(2,4-dimethylvaleronitrile) was used to generate the alkylperoxyl radicals. The reaction products of α-tocopherol were isolated by reverse-phase and normal-phase high performance liquid chromatography, and their structures were characterized by infrared, ultraviolet,1H and13C nuclear magnetic resonances and mass spectrometry. They were 8aS-hydroperoxy-α-tocopherone, 8aR-hydroperoxy-α-tocopherone, a mixure of 7,8-epoxy-8aS-ethoxy-α-tocopherone, and 7,8-epoxy-8aR-ethoxy-α-tocopherone, 8aS-(1R-cyano-1,3-dimethyl)butylperoxy-α-tocopherone, 8aS-(1S-cyano-1,3-dimethyl)butylperoxy-α-tocopherone, a mixture of 8aR-(1S-cyano-1,3-dimethyl)butylperoxy-α-tocopherone and 8aR-(1S-cyano-1,3-dimethyl)butylperoxy-α-tocopherone, 4aR,5S-epoxy-8aS-ethoxy-α-tocopherone, 4aS,5R-epoxy-8aS-ethoxy-α-tocopherone and 4aR,5S-epoxy-8aR-ethoxy-α-tocopherone.  相似文献   
42.
A cell immobilization technique to prevent cell leakage from the matrix in a very common system, alginate-Saccharomyces cerevisiae, was investigated. A double coating of immobilized cell beads prevented leakage very well in flask fermentation even when shaking was applied. The suitable concentrations of sodium alginate were 5, 5 and 3 wt% for the core, internal coating and external coating, respectively. The suitable concentration of calcium chloride was 1 wt% for all cases. Fermentation using a fixed bed reactor containing the immobilized cells was carried out successfully for 25 d.  相似文献   
43.
A new extractant biuret(C8) is synthesized and tested for solvent extraction of hard acid metals, for example, actinides, and soft acid metals. This compound has a central frame similar to that of malonamide but with an additional amino functional group introduced into the central framework; in this case, both the amidic oxygen atoms and the amino nitrogen atom may bond with metals. We found that both hard and soft acid metals can be extracted from nitric or perchloric acids to n-dodecane using biuret(C8). It is clear that D(Pd, Pu, U) values of approximately 100 can be obtained using 0.1 M biuret(C8)/n-dodecane.  相似文献   
44.
A simple method for intraliposomal entrapment of platinum complexes is presented, where hydrophilic platinum oligonuclear complexes, 1-methyluracil green (MeUG), uridine green (UdG) and uridine blue (UdB), are included inside liposomes and allowed to react with bilayer lipids. The liposomes prepared in this method exhibit higher entrapment efficiency and higher distribution to organs (liver, kidney, spleen, lung) and blood (but not B16 cancer cells) than those prepared from mononuclear Pt complexes [cis-diamminedichloroplatinum, cis-diammine-1,1′-dicarboxylatocyclobutaneplatinum, and cis-dichloro-cis-dihydroxy-trans-bis(isopropylamine)platinum)].  相似文献   
45.
A simple method for intraliposomal entrapment of platinum complexes is presented, where hydrophilic platinum oligonuclear complexes, 1-methyluracil green (MeUG), uridine green (UdG) and uridine blue (UdB), are included inside liposomes and allowed to react with bilayer lipids. The liposomes prepared in this method exhibit higher entrapment efficiency and higher distribution to organs (liver, kidney, spleen, lung) and blood (but not B16 cancer cells) than those prepared from mononuclear Pt complexes [cis-diamminedichloroplatinum, cis-diammine-1,1′-dicarboxylatocyclobutaneplatinum, and cis-dichloro-cis-dihydroxy-trans-bis(isopropylamine)platinum)].  相似文献   
46.
Enterococcus faecium NKR-5-3 produces four antimicrobial peptides referred here as enterocins NKR-5-3A, B, C and D. A two-step electrospray ionization-liquid chromatography and mass spectrometry (ESI-LC/MS)-based quantification system was developed to monitor its multiple bacteriocin production profiles, which is essential in understanding the complex production regulation mechanism of strain NKR-5-3. The developed ESI-LC/MS-based quantification system can easily monitor the multiple bacteriocin production of this strain. Using the developed system, the production of enterocin NKR-5-3B was found to be not as variable as those of the other enterocins in different cultivation media. Production of enterocin NKR-5-3B was also found to have a wider optimum incubation temperature (20-30°C) than enterocins NKR-5-3A, C and D (25°C). Furthermore, at least 2?nM of the bacteriocin-like inducing peptide, enterocin NKR-5-3D, regulated the production of NKR-5-3 enterocins except enterocin NKR-5-3B. These findings taken together suggest that enterocin NKR-5-3B has an independent production regulation mechanism from the other NKR-5-3 enterocins. The developed system could effectively pin-point the production profiles of the multiple bacteriocins of E.?faecium NKR-5-3 under different fermentation conditions.  相似文献   
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We retrospectively reviewed the CT scans of 25 primary lung cancers with disseminated pleural nodules or minimal malignant pleural effusions that were not recognized preoperatively. Special attention was devoted to abutting interlobar fissures, thick major fissures, and disseminated nodules on the chest wall, the diaphragm, and in the interlobar fissures. Among 10 primary tumors abutting interlobar fissures, nine (90%) had at least one of these findings. Among 15 primary lung tumors which did not abut interlobar fissures, four (27%) had at least one of these findings. We conclude that CT is a useful modality for detecting the pleural dissemination of primary lung cancers when primary lung cancers abut interlobar fissures even if no pleural effusion is detectable on CT.  相似文献   
50.
The effect of alloying elements on neutron irradiated FeCu alloys has been investigated in order to obtain the fundamental information on the irradiation-enhanced copper embrittlement for power reactor vessel steels. The mechanism of copper-induced irradiation embrittlement in the copper-containing iron alloys was proved to be due to both the interaction of copper atoms with irradiation-produced complex defects within grains, and the preferred grain boundary segregation of copper atoms existing near grain boundaries. The former effect causes the increase of yield strength, and the latter results in the ductility loss and grain boundary crackings. The addition of titanium up to 0.4 wt% to the Fe-0.1 wt% Cu alloy was found to be extremely effective in the improvement of both the irradiation-induced ductility loss and strength. Aluminum and silicon were not as effective as titanium.  相似文献   
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