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991.
P.Mick Richardson 《Biochemical Systematics and Ecology》1982,10(2):197-199
Published results of the distribution of anthocyanins in the Sterculiaceae have been re-interpreted on the basis of the phylogenetic status of the compounds present. A flavonoid score system was less useful than a cladistic interpretation based on Hennigian arguments. 相似文献
992.
993.
A. C. Smith 《Journal of fish biology》1980,16(1):1-4
Evidence is presented of lethal blood clot formation in fishes. A variety of factors commonly encountered under aquacultural conditions may generate such clots. 相似文献
994.
Sequences related to the major subunit gene fedA of F107 fimbriae in porcine Escherichia coli strains that express adhesive fimbriae 总被引:1,自引:0,他引:1
Abstract Porcine Escherichia coli strains isolated from cases fo postweaning diarrhea or edema disease were analysed for the presence of fedA , the major subunit gene of F107 fimbriae. The E. coli isolates were known to contain colonisation factor '8813', or to express F107, 2134P or other fimbriae, different from F4, F5, F6, and F41. PCR with fedA -specific primers, restriction enzyme digestion of the PCR product, and nucleotide sequence analysis demonstrated that 2134P pili, colonisation factor '8813' and fimbriae identified on Australian strains of the O141 serotype belong to one family of F107 fimbrial antigens. 相似文献
995.
996.
997.
998.
Are all plant populations metapopulations? 总被引:2,自引:1,他引:1
999.
P Sinibaldi R Muraro M Centanni M G Giganti 《Bollettino della Società italiana di biologia sperimentale》1983,59(1):112-116
The behaviour of Na+/K+ ATPase during cell growth has been studied. Human cultured fibroblasts were used in the presence or absence of EGF. Sample and control cultures were stopped by gathering and washing the cells with tris buffer. Homogenates were tested for Na+/K+ ATPase activity by the method of incubating and for the -SH groups content (Ellman). Na+/K+ ATPase activity that slightly increases in the controls is strongly reduced by the addition of EGF. The behaviour shows evidence for a double mechanism of action: I) involvement of the cAMP system 2) decrease of the -SH group availability. 相似文献
1000.
P Gysen G Heynen P Franchimont 《Comptes rendus des séances de la Société de biologie et de ses filiales》1980,174(5):867-877
Proteoglycans (PG) have been purified by classical methods from human articular cartilage in order to set up a radioimmunoassay. Conditions of labelling, purification of labelled PG, and optimal conditions of buffer, temperature, duration of incubations and dilution of antiserum are described. Separation of free and bound PG is performed by immunoprecipitation. It is demonstrated that human articular PG can be assayed quantitatively by RIA procedure, with the sensitivity of +/- 2 femto-moles (+/- 5 ng) per tube. 相似文献