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排序方式: 共有240条查询结果,搜索用时 125 毫秒
1.
Vichuta Lauruengtana Arisa Yanagita Tze Loon Neoh Takeshi Furuta Muneyoshi Kanai Haruyuki Iefuji Hidefumi Yoshii 《Biotechnology journal》2010,5(5):470-476
S-Adenosyl-L -methionine (SAM) is an essential metabolite in all living organisms. In clinical research, SAM has also been suggested as a chemotherapeutic agent in various diseases. The main problem of SAM is its instability at high temperatures, at neutral and alkaline pH, and in the presence of humidity. SAM retention in spray-dried powder was determined under various conditions of spray-drying. The highest SAM retention was obtained when maltodextrin (dextrose equivalent, DE, of 25) was used as the carrier solid with the SAM feed liquid at pH 4.0. The water content in the powder had a significant effect on the stability of SAM. SAM powder with lower water content exhibited higher stability. 相似文献
2.
Toshihiko Umemoto Isamu Namikawa Zensaku Yoshii Hisanori Konishi 《Microbiology and immunology》1982,26(3):191-198
The osmium-dimethyl sulfoxide-osmium method for clear visualization of intracellular structure was used to observe the detailed inner structure of the spherical bodies produced in vitro by a human oral treponeme. Scanning electron microscopy of the cracked spherical body revealed no morphological differences between the outer and inner surfaces of the spherical body membrane, and that multiple folded or somewhat linear main bodies adhere closely to the inner surface. In addition, axial flagella partially free from the main bodies spread widely within the body to make a network, and a number of blebs ranging from approximately 1 μm to 0.2 μm in diameter were located near the terminal or subterminal areas of the main bodies. The origin of the blebs and the mechanism of spherical body formation are discussed. 相似文献
3.
Shigeki Takeura Hiizu Aoki Tatsuya Tsurumi Yukihiro Nishiyama Hisashi Fujioka Saiji Yoshii Koichiro Maeno 《Microbiology and immunology》1984,28(4):427-437
Host-dependent restriction of influenza B virus replication in L cells was analysed in comparison with productive infection in MDCK or 1–5C-4 cells. The synthesis and intracellular distribution of virus-specific proteins and the production of cytoplasmic ribonucleoproteins in nonpermissive L cells were similar to those in permissive MDCK cells. However, an electron microscopic study of infected L cells showed neither extracellular virions nor budding virus particles on the cell surface, in contrast to MDCK cells which produced numerous virus particles. PAGE analysis of the plasma membrane isolated from the cells demonstrated no significant difference in the composition of viral polypeptides between permissive 1-5C-4 and nonpermissive L cells. It was noted that the abortiveness of influenza B virus infection in L cells may be due to a defect in host cell function involved in the initiation of virus budding. 相似文献
4.
To reveal the difference of molecular property between structurallysimilar odorless and odoriferous musk compounds, 10 pairs ofbenzenoids (monocyclic-, dicyclic- and tricyclic-) were examined.Molecular structures of all compounds were optimized by MNDO(modified neglect of diatomic differential overlap) consideringconformation. Parameters effective in discriminating two groups,group A of 10 odorless compounds and group B of 10 musk odorcompounds, were searched from 34 candidate parameters by adaptiveleast squares. The best three parameters found were log P value(octanol/water partition coefficient), the longest side lengthof hexahedron circumscribing a molecule, and the parameter whichexpresses structural hindrance to the functional group whena molecule approaches the receptor site. The two groups of compoundswere completely discriminated using these three parameters. 相似文献
5.
Spiral conformation of Vibrio cholerae as determined by scanning electron microscopy of elongated cells induced by cephalexin treatment. 总被引:1,自引:0,他引:1 下载免费PDF全文
The elongated cells of Vibrio spp. induced by cephalexin treatment were examined by scanning electron microscopy. The results showed that Vibrio cholerae has a twisted cell body and a right-handed spiral conformation and that the cell bodies of V. parahaemolyticus and V. alginolyticus are straight rather than curved. 相似文献
6.
Genome type analysis of adenovirus type 4 isolates, recently obtained from clinically different syndromes in some areas in Japan 总被引:1,自引:0,他引:1
C S Ren N Nakazono S Ishida S Fujii T Yoshii S Yamazaki K Ishii K Fujinaga 《Japanese journal of medical science & biology》1985,38(4):195-199
DNA cleavage analyses with EcoRI, HindIII and BamHI were carried out to investigate genome types of recent Ad 4 isolates obtained from acute respiratory disease (8 strains), and ocular disease (11 strains) in Japan. DNA cleavage patterns of all 19 isolates studied were identical regardless of whether they were recovered from respiratory tract or conjunctiva, but were distinct from that of the prototype strain. 相似文献
7.
M Kuwabara G Yoshii T Itoh 《International journal of radiation biology and related studies in physics, chemistry, and medicine》1983,44(2):219-224
Free radicals produced by the reactions of hydrated electrons with pyrimidine nucleosides halogenated at the sugar moiety (2'-chloro-2'-deoxyuridine and 2'-chlorothymidine) were studied by e.s.r. and spin-trapping. 2-Methyl-2-nitrosopropane was used as the spin-trap. The usual spin-trapping technique was extended to frozen and deoxygenated systems to avoid contamination of the trapped radicals with side-products by spin-trapping 2-methyl-2-nitrosopropane itself. When this method was applied to 2'-chloro-2'-deoxyuridine, a free radical at the C-2' position of the sugar moiety was spin-trapped together with a free radical at the C-5 position of the base moiety. This indicates that hydrated electrons both add to the base moiety and eliminate halogen anions from the halogenated sugar moiety. In the case of 2'-chlorothymidine, however, only a free radical attributed to H-addition at the C-6 position of the thymine base was observed. No radicals produced by the reaction of hydrated electrons with the halogenated sugar could be spin-trapped. 相似文献
8.
Yoshio Kawahara Yasuhiko Yoshihara Shigeho Ikeda Hiroe Yoshii Yoshio Hirose 《Applied microbiology and biotechnology》1990,34(1):87-90
Summary The growth rate, sugar consumption rate, and production rate of an l-lysine producing Brevibacterium lactofermentum mutant were stimulated by addition of exogenous glycine betaine. Glycine betaine stimulated the growth rate especially in media of inhibitory osmotic stress, and the stimulation was independent of any specific solute. Therefore growth stimulation by glycine betaine was considered to be an osmoprotective effect. A strong enhancement of the sugar consumption rate and the l-lysine production rate was observed even with resting cells under osmotic stress as well as in a fermentation with growing cells. These data indicated that the osmoprotective effects of glycine betaine on l-lysine production can be independent of protein synthesis.
Offprint requests to: Yoshio Kawahara 相似文献
9.
10.
In order to confirm the occurrence of 3 alpha, 6 alpha, 7 alpha, 12 alpha-tetrahydroxy-5 beta-cholestanoic acid in Zellweger's syndrome, the nature of tetrahydroxycholestanoic acids present in a patient with this disease was studied. Urinary bile acids were extracted with a Sep-pak C18 cartridge and methylated after alkaline hydrolysis. The methyl esters were purified by silica gel column chromatography, and the methyl tetrahydroxycholestanoate fraction was analyzed by gas liquid chromatography-mass spectrometry. Along with already known side chain hydroxylated derivatives of 3 alpha, 7 alpha, 12 alpha-trihydroxy-5 beta-cholestanoic acid, 3 alpha, 7 alpha, 12 alpha, 24- and 3 alpha, 7 alpha, 12 alpha, 26-tetrahydroxy-5 beta-cholestanoic acids, three nuclear hydroxylated derivatives of 3 alpha, 7 alpha, 12 alpha-trihydroxy-5 beta-cholestanoic acid were found. One of them was identified as 3 alpha, 6 alpha, 7 alpha, 12 alpha-tetrahydroxy-5 beta-cholestanoic acid by direct comparison with the authentic standard which was chemically synthesized from 3 alpha, 6 alpha, 7 alpha, 12 alpha-tetrahydroxy-5 beta-cholanoic acid by side chain elongation. 相似文献