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721.
A method has been developed for the determination of flutroline in plasma using capillary gas chromatography and selected ion monitoring detection of the TMS derivative. The method is linear over the concentration range of 3-60 ng ml-1 and was used to define the drug pharmacokinetics and bioavailability in animals and man. A novel method for direct derivatization on the tip of a moving needle injector is described. 相似文献
722.
723.
724.
Keith P. Hertzog Frank Falkner Stanley M. Garn 《American journal of physical anthropology》1969,30(1):141-143
Serial hand-wrist x-rays of 81 pairs of twins were examined to investigate the genetics of ossification sequence polymorphism. Discordance in ossification sequence was 3.5 times more common between like-sex dizygotic twins than between monozygotic twins, with the difference being significant at the 0.01 level of confidence. These findings support the contention that the major part of variation in ossification sequence is genetically determined. 相似文献
725.
726.
The morphologically conspicuous bivalve Oxytoma (Palmoxytoma) cygnipes (Young & Bird, 1822), known for its palaeogeographically bipolar distribution, from a limestone bed in the boundary “Belemniten–Schichten”/Amaltheenton
formation, Lower Jurassic, in N Germany is described. The occurrence of this palaeoceanographically significant bivalve points
to an influx of cool seawater from the Arctic to the North-German Basin at the base of the Upper Pliensbachian, just before
the deposition of the Amaltheenton formation. A review of previously reported occurrences on the NW European Shelf indicates
two distinct stratigraphic intervals of occurrence of this taxon: the Rhaetian–Hettangian boundary and the Upper Pliensbachian.
Whereas the former interval of occurrence may be related to short-term cooling in the course of the end-Triassic extinction
event, the latter is interpreted as reflecting the influx of a cool water current to the eastern part of the NW European Shelf,
which continued southwards parallel to the coast of the Bohemian–Vindelician High. 相似文献
727.
Fluvival tufa formation in a hard-water creek (Deinschwanger Bach, Franconian Alb, Germany) 总被引:2,自引:0,他引:2
Summary Cyanobacteria-dominated biofilms involved in tufa deposition in the hardwater creek Deinschwanger Bach, Bavaria, were investigated
with regard to their effect on the carbonate equilibrium and fabric formation. Current tufa deposition is evident by up to
1.5 mm thick crusts that have formed on substrate plates placed in the creek for 10 months. Hydrochemistry data indicate that
carbonate precipitation along the creek is physicochemically driven by CO2 degassing, whereas photosynthetic carbon assimilation is without detectable effect on the macroscale carbonate equilibrium.
However, stable isotope data indicate a minor photosynthetic effect, but only for the lower creek section where the pCO2 already drops to the two-fold of the atmospheric level. Though the initial process of external nucleation on cyanobacterial
sheaths in the lower creck section might be promoted of by a photosynthetically-induced microscale pH gradient, the effect
is not strong enough to cause a CaCO3 impregnation of the sheaths. The fabric of the laminated tufa crusts in the creek reflects the temporal alternation of porous
microspariticPhormidium incrustatum-Phormidium foveolarum-diatom biofilms in spring, micrite-impregnatedPhormidium incrustatum-Phormidium foveolarum-diatom biofilms in summerautumn, and detritus-rich non-calcified diatom-biofilms in winter. By contrast, exopolymer-poor
surfaces of cascade tufa mosses show large, euhedral spar crystals. Non-phototrophic bacteria, which occur in large numbers
inPhormidium incrustatum-Phormidium foveolarums-diatom-communities, thrive on extracellular polymeric substances (EPS) and dead cells of the cyanobacteria and are unlikely
to promote CaCO3 precipitation. 相似文献
728.
By adding leaf peroxisomes to purified intact chloroplasts, glycine synthesis was reconstituted. On adding leaf mitochondria, serine synthesis was also reconstituted. However, aromatic amino acid synthesis which was effected by purified chloroplasts was not enhanced on adding peroxisomes or mitochondria although the rate in whole leaves was considerably higher. 相似文献
729.
F C Falkner 《Prostaglandins》1979,18(5):779-786
After intratracheal administration to rats, the bronchodilator N-acetyl PGE2 carboxamide was converted rapidly to PGE2 and 13,14-dihydro-15-keto-PGE2, the major plasma metabolite. Oxidation of the N-acetyl carboxamide by prostaglandin dehydrogenase and hydrolysis of the imide bond were demonstrated in vitro. 相似文献
730.