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61.
Marie-Aleth Dubois Anne Zoll Kenneth R. Markham Marie Louise Bouillant Georgette Dellamonica Jean Chopin 《Phytochemistry》1984,23(3):706-707
The new C-glycosyiflavone, 6-C-β-d-glucopyranosyl-8-C-β-d-galactopyranosylapigenin, has been isolated from Cerastium arvense and identified on the basis of UV, MS and 13C NMR spectral data and comparison with the product obtained from 6-C-galactosylation of vitexin. 相似文献
62.
Interactions of Photobleaching and Inorganic Nutrients in Determining Bacterial Growth on Colored Dissolved Organic Carbon 总被引:8,自引:0,他引:8
Abstract Bacteria are key organisms in the processing of dissolved organic carbon (DOC) in aquatic ecosystems. Their growth depends on both organic substrates and inorganic nutrients. The importance of allochthonous DOC, usually highly colored, as bacterial substrate can be modified by photobleaching. In this study, we examined how colored DOC (CDOC) photobleaching, and phosphorus (P) and nitrogen (N) availability, affect bacterial growth. Five experiments were conducted, manipulating nutrients (P and N) and sunlight exposure. In almost every case, nutrient additions had a significant, positive effect on bacterial abundance, production, and growth efficiency. Sunlight exposure (CDOC photobleaching) had a significant, positive effect on bacterial abundance and growth efficiency. We also found a significant, positive interaction between these two factors. Thus, bacterial use of CDOC was accelerated under sunlight exposure and enhanced P and N concentrations. In addition, the accumulation of cells in sunlight treatments was dependent on nutrient availability. More photobleached substrate was converted into bacterial cells in P- and N-enriched treatments. These results suggest nutrient availability may affect the biologically-mediated fate (new biomass vs respiration) of CDOC. 相似文献
63.
D. Mercanti A. Angelini MT. Ciotti ML. Eboli C. Galli L. Battistini D. Merlo P. Calissano 《Cytotechnology》1993,11(Z1):S117-S119
The neurite outgrowth and adhesion complex (NOAC), isolated from rabbit sera has been dissociated in its major components by reverse-phase chromatography in HPLC by using a C18 column. SDS-PAGE analisys of the active fractions revealed the presence of three major bands of approximately 100, 70 and 50 kDa. Studies on the biological activity of NOAC were carried out on rat cerebellar granule cells. NOAC-cultured cells exhibit a marked resistance to excitotoxic stimuli carried by glutamate. 相似文献
64.
Four C-glucosylflavones were isolated from muskmelon leaves and shown to be 6-C-diglucosylapigenin (meloside A),6-C-diglucosyl-luteolin (meloside L) and the respective caffeyl esters of meloside A (meloside a) and meloside L (meloside I). 相似文献
65.
Kenneth R. Markham Lawrence J. Porter Ella O. Campbell Jean Chopin Marie-Louise Bouillant 《Phytochemistry》1976,15(10):1517-1521
Evidence based on flavonoid constituents is cited in support of the existence of two species in the genus Hymenophyton, H. flabellatum and H. leptopodum. A number of apigenin 6,8-di-C-pentosides and pentoside-hexosides are common to both species but the proposed additional species, H. leptopodum, is distinguished from H. flabellatum by the presence of kaempferol di- and triglycosides. This is the first detailed study of the flavonoid chemistry of any member of the order Metzgeriales and the significance of the findings is discussed. 相似文献
66.
67.
J. Chopin G. Dellamonica M.L. Bouillant A. Besset G. Popovici G. Weissenböck 《Phytochemistry》1977,16(12):2041-2043
Avena sativa leaves, stems and inflorescences contain a range of new C-glycosylflavone 2″-O-glycosides, including vitexin and isoswertisin 2″-rhamnosides, isovitexin and isoorientin 2″-arabinosides. The structure of ‘vitexin 4′-rhamnoside’ from Crataegus oxyacantha is revised in vitexin 2″-rhamnoside. 相似文献
68.
Distribution of the molossinus allele of Sry, the testis-determining gene, in wild mice 总被引:3,自引:0,他引:3
Nagamine CM; Shiroishi T; Miyashita N; Tsuchiya K; Ikeda H; Takao N; Wu XL; Jin ML; Wang FS; Kryukov AP 《Molecular biology and evolution》1994,11(6):864-874
When the Y chromosome of the laboratory inbred mouse strain C57BL/6 (B6) is
replaced by the Y of certain strains of Mus musculus domesticus, testis
determination fails and all XY fetuses develop either as hermaphrodites or
XY females (XY sex reversal). This suggests the presence of at least two
alleles of Sry, the male-determining gene on the Y:M. m. domesticus and B6.
The B6 Y chromosome is derived from the Japanese house mouse, M. m.
molossinus and therefore carries a molossinus Sry allele. As a first step
to determine how the molossinus Sry allele evolved, its distribution
pattern was determined in wild mice. The cumulative data of 96 M. musculus
samples obtained from 58 geographical locations in Europe, North Africa,
and Asia show the molossinus Sry allele is restricted to Japan and the
neighboring Asian mainland and confirm that Japanese M. m. molossinus mice
were derived in part from a race of M. m. musculus from Korea or Manchuria.
Sry polymorphisms, as illustrated by the molossinus Sry allele, can serve
as molecular markers for studies on the evolution of wild M. musculus
populations and can help determine the role sex determination plays in
speciation.
相似文献
69.
One of the cellular defenses against virus infection is the silencing of viral gene expression. There is evidence that at
least two gene-silencing mechanisms are used against the human immuno-deficiency virus (HIV). Paradoxically, this cellular
defense mechanism contributes to viral latency and persistence, and we review here the relationship of viral latency to gene-silencing
mechanisms. 相似文献
70.
Further evidence for the establishment of the pig fallopian tube (PFT) cell line as a continuous cell line was shown by an increase in the maximum population density as the number of subcultures increased. The optimal pH and temperature-growth ranges appeared to be 7.4-7.8 and 37-41 degrees C respectively, and the population doubling time was 20-25 h under optimal growth conditions. With progressive subculture, the serum requirements dropped from 20 to 2%. A plating efficiency of 2 to 4% was found in all serial subcultures. Colonies were observed in agar suspension culture at the 146th subculture and thereafter. Chromosomal alterations were found in the 100th subculture and thereafter. 相似文献