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51.
52.
Jrn Piel Jens Donath Katja Bandemer Wilhelm Boland 《Angewandte Chemie (International ed. in English)》1998,37(18):2478-2481
Terpenoids from flower and leaf volatiles are predominantly synthesized along the mevalonate-independent pathway, as shown by administration of [D2]deoxy-D -xylulose and [D5]mevalolactone. The parallel use of two pathways for the biosynthesis of the sesquiterpenoid-derived 4,8-dimethylnona-1,3,7-triene (DMNT, see picture) may be important to ensure the synthesis of the volatile alarm codes of plants. 相似文献
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An immunoglobulin-rich fraction has been prepared from ovine blood in our laboratory. We have investigated its antibacterial
activity and binding activity to pathogenic whole cell antigens, lipopolysaccharide (LPS) and staphylococcal enterotoxin B.
Ovine immunoglobulin concentrate (OIC) comprised about 73 ± 2% of IgG and 11 ± 1% of IgM on a protein basis. It inhibited
the growth of all 13 strains of pathogens tested, but the inhibitory activity varied according to bacterial strain. The inhibitory
activity of OIC was attributed to the high contents of undenatured immunoglobulin present because its inhibitory activity
was destroyed by pepsin digestion and heat treatment (65°C for 30 min). OIC bound to all the Gram-positive and Gram-negative
pathogens, regardless of cell wall structure. The highest magnitude of crossreactivity to whole cell antigens was against
Staphylococcus epidermidis and Shigella soneii strains (p < 0.001). The binding activity of OIC to LPS obtained from Escherichia coli O111:B4 and Salmonella enterica serotype typhimurium was assessed by enzyme-linked immunosorbent assay and lymphoblast K-562 proliferation assay. OIC bound to LPS with a binding
activity that was dependent on OIC concentration and saturable, showing typical hyperbolic curves. For toxin-binding activity,
an OIC concentration-dependent trend like that for LPS-binding activity was also observed. This preliminary evidence suggests
that the OIC used in this study could be a promising supplement for protecting against pathogenic bacteria. 相似文献
55.
Saini R Boland S Kataeva O Schmidt AW Kurzchalia TV Knölker HJ 《Organic & biomolecular chemistry》2012,10(21):4159-4163
A stereoselective synthesis of (25S)-Δ(1)-, (25S)-Δ(1,4)-, (25S)-Δ(1,7)-, (25S)-Δ(8(14))-, (25S)-Δ(4,6,8(14))-dafachronic acid, methyl (25S)-Δ(1,4)-dafachronate and (25S)-5α-hydroxy-3,6-dioxocholest-7-en-26-oic acid is described. (25S)-Δ(1,4)-Dafachronic acid and its methyl ester are natural products isolated from corals and have been obtained by synthesis for the first time. (25S)-5α-Hydroxy-3,6-dioxocholest-7-en-26-oic acid represents a promising synthetic precursor for cytotoxic marine steroids. 相似文献
56.
Accelerated label setting algorithms for the elementary resource constrained shortest path problem 总被引:1,自引:0,他引:1
A label setting algorithm for solving the Elementary Resource Constrained Shortest Path Problem, using node resources to forbid repetition of nodes on the path, is implemented. A state-space augmenting approach for accelerating run times is considered. Several augmentation strategies are suggested and compared numerically. 相似文献
57.
In higher plants, the two homoterpenes 4,8-dimethyinona-1,3,7-triene ( 1 ) and 4,8,12-trimethyltrideca-1,3,7,11-tetraene ( 2 ) are synthesized from the regular terpene alcohols nerolidol and geranyllinalool by fragmentation into the homoterpene and butenone. The biosynthetic pathway is evidenced by conversion of (2H)nerolidol in Hoya purpureo-fusca, Magnolia liliiflora nigra, Robinia pseudoacacia, and Philadelphus coronarius. 相似文献
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Swartz M Abrams GS Adolphsen CE Averill D Ballam J Barish BC Barklow T Barnett BA Bartelt J Bethke S Blockus D Bonvicini G Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan DE Dorfan JM Drewer DC Elia R Feldman GJ Fernandes D Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gatto C Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Grindhammer G Grosse-Wiesmann P Hanson G Harr R Harral B 《Physical review letters》1990,64(24):2877-2880