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51.
Four monolignol glucosides have been isolated and identified from the needles of Pinus contorta. Chavicol 4-O-α-L-arabinofuranosyl-(1 → 相似文献
52.
From fresh Pinus contorta Doug (Coastal) needles four flavonol acylated glucosides and 6-methyl-kaempferol 3-β-D-glucoside were isolated. The three monoacylated glucosides were kaempferol-3-β-D(6-O-p- coumaryl)glucoside, isorhamnetin-3-β-D-(6-O-acetyl)glucoside, quercetin-3-β-D-(p-coumaryl)glucoside and the diacyl compound was kaempferol-3-β-D-(di-p-coumaryl)glucoside. 相似文献
53.
Jiří Ponert 《Folia Geobotanica》1977,12(1):9-22
Studies of the Adjarian flora resulted in a detailed classification of the ergasiophygophytes, based mainly on the degree of their naturalization: (1) The ephemeroergasiophygophytes display unstable naturalization both in artificial and natural habitats, and disappear after only a few growing seasons. (2) The deuteroergasiophygophtes show stable naturalization in anthropogenic habitats. (3) The protoergasiophygophytes are distinguished by uncertain stability of naturalization in natural habitats, and, if firmly naturalized on a certain spot, they lack any tendency to further spreading. (4) The autergasiophygophytes tend to spread in natural habitats. (5) The aggressive ergasiophygophytes transform natural vegetation in new plant communities, and can become dominant species in these communities. New terms, viz. emphemeroxenophytes, protoneophytes, non-aggressive neophytes, slightly aggressive neophytes, and postneophytes with vegetative reproduction have also been introduced to express diverse features of the xenophytes. 相似文献
54.
The variety of life-history patterns exhibited by the five species of wrasse common in Northern Europe are reviewed. The two larger wrasse species, the ballan, Labrus bergylta Ascanius, and cuckoo, Labrus mixtus (L.), are exploited through sport angling. The three smaller species, the corkwing, Symphodus (Crenilabrus) melops (L.), rock cook, Centrolabrus exoletus (L.) and goldsinny, Ctenolabrus rupestris (L.), are being exploited by a new fishery for use as parasite cleaners of farmed salmon.
The nature of salmon farming limits the wrasse fishery to a minimum size, restricted areas and the warmer months of the year. The fishery may be expected to alter population structure through selective removal of larger fish. Removal of dominant territorial males may affect social structures and removal of nest-guarding males would reduce egg survival. Quantitative models incorporating stock size and fishery requirements are now required. 相似文献
The nature of salmon farming limits the wrasse fishery to a minimum size, restricted areas and the warmer months of the year. The fishery may be expected to alter population structure through selective removal of larger fish. Removal of dominant territorial males may affect social structures and removal of nest-guarding males would reduce egg survival. Quantitative models incorporating stock size and fishery requirements are now required. 相似文献
55.
A new method is proposed for the microtitration of CBPP vaccines by performing eight parallel endpoint two-fold dilutions. When performed on a 96-well plate, it gives a titre with a precision of +/- 0.2 log10. By comparison, the established method, performed in tubes, gives a precision of only +/- 0.6 log10. The adaptation to microtitre plates allows much more economical culture of larger numbers of samples. Statistical analysis permits determination of vial-to-vial homogeneity of a batch and calculation of a titre with a precision of +/- 0.09 log10. The new method may be applied for the titration of mycoplasmas. 相似文献
56.
Jiří Váňa 《Folia Geobotanica》1982,17(1):63-87
The present study deals with five genera of hepatics in Africa, Isotachis Mitt., Anastrophyllum (Spruce) Steph., Tritomaria Schiffn. ex Loeske, Gymnocoleopsis (Schust.) Schust. and Lophozia (Dum.) Dum. All African populations of the genus Isotachis Mitt. are considered to be one species, I. aubertii (Schwaegr.) Mitt. Four species of Anastrophyllum (Spruce) Steph. (s.l.), A. auritum (Lehm.) Steph., A. piligerum (Nees) Spruce, A. subcomplicatum (Lehm. et Lindenb.) Steph. and A. minutum (Schreb.) Schust., and two species of Tritomaria Schiffn. et Loeske, T. camerunensis S. Arnell and T. exsecta (Schrad.) Schiffn. ex Loeske occur in Africa. Gymmocoleopsis multiflora (Steph.) Schust. represents a genus and species hitherto unreported for the African flora. Finally, five Lophozia (Dum.) Dum. species, L. argentina (Steph.) Schust., L. capensis S. Arnell, L. decolorans (Limpr.) Steph., L. hedbergii S. Arnell and L. tristaniana (S. Arnell) Váňa, are reported from central and southern Africa; two of these (L. argentina (Steph.) Schust. and L. decolorans (Limpr.) Steph.) represent the first reports from Africa. 相似文献
57.
Dagmar Jičínská Eduard Brabec Marcel Rejmánek Jan Jeník Joří Haager Josef Holub Věroslav Samek Hana Rambousková Josef Holub Marie Naděžda Končalová Robert Neuhäusl Josev Kyncl František Krahuleo Jaroslav Dobrý Blanka Úlehlová Jiří Úlehla Eliška Rybníčková Kamil Rybníček 《Folia Geobotanica》1982,17(4):431-448
58.
59.
Mechanism of activation of cyclic GMP-dependent protein kinase from rat liver by multiple modulators
Charles W. Mackenzie III Thomas E. Donnelly Jr. 《Biochimica et Biophysica Acta (BBA)/General Subjects》1980,633(3):444-456
A number of polyanionic compounds, including DNA, RNA and polyglutamate, were shown to exhibit protein kinase stimulatory modulator activity as they were required for cyclic GMP to stimulate the phosphorylation of various cationic substrates by rat liver cyclic GMP-dependent protien kinase. Anionic proteins (casein, phosvitin) were phosphorylated poorly by the enzyme and their phosphorylation was not stimulated by the stimulatory modulators. Studies of the mechanism of action suggest that the modulators interact directly with the substrates to form a complex which is a better substrate than free histone. The observed effect of modulator is complex as it depends on the ratio of modulator to histone and the resultant state of the complex formed (better or poorer substrate than free histone). The observed effect is also dependent on the properties of the histone substrate as Michaelis-Menten kinetics are not observed in the phosphorylation of arginine-rich histone in the absence or presence of cyclic GMP. 相似文献
60.
Jiří Dostálek 《Folia Geobotanica》1980,15(1):59-73
Pyrus spinosa Forsk. (=P. amygdaliformis Will.) kreuzt sich in beträchtlichem Masse mitP. pyraster Burgsd. und mitP. communis L. Es wurden drei Hybriden beschrieben, die zwar weniger, aber gut keimende Samen haben. Potentiell sind in der bulgarischen Population vonP. spinosa Merkmale aller infraspezifischen Taxa vertreten, doch nur zwei von ihnen kommen in grösserem Masse vor, das Vorkommen der weiteren drei ist nur gering. Merkmale des übrigen infraspezifischen Taxon kommen nur in Kombination mit Merkmalen anderer Taxa bei Übergangsformen vor. Vorläufig ist auch die Verbreitung vonP. spinosa und ihrer Hybriden in Bulgarien angegeben. 相似文献