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93.
New nomenclatural combinations are validated for fifteen taxa belonging to the generaDanthonia, Stipa, Lolium, Phippsia, Elymus, Schoenoplectus andAllium. 相似文献
94.
Haemagglutination by influenza virus strains PR8 and Lee as well as treatment of red blood cells by periodate produced numerous and manifold changes in the lipids and the amino acid composition of the erythrocytes. The changes induced by the influenza strains differed from each other and from those induced by periodate. Alterations in the membrane lipids observed after haemagglutination by heat treated strain PR8 and by its native form were identical. 相似文献
95.
The dose-related effects of cysteamine treatment on hypothalamic and striatal neurotransmission were investigated. Cysteamine pretreatment with a dose of 150 mg/kg slightly increased the dopamine, and markedly decreased the noradrenaline, content of the hypothalamus in a dose-related manner. The serotonin levels of the hypothalamus and striatum were not affected. Cysteamine pretreatment with a higher dose (300 mg/kg sc) slightly increased the uptake of noradrenaline into hypothalamic slices. The drug did not influence dopamine and serotonin uptake into hypothalamus and striatal slices. These results suggest that cysteamine decreases rather selectively the noradrenaline content of the hypothalamus. 相似文献
96.
Reversed-phase high-performance liquid chromatography together with fluorescence detection is suitable for the determination of urinary porphyrin carboxylic acid isomers, and Copro I and III, as well as Uro I and III porphyrin isomers are separated simultaneously. 相似文献
97.
ALBERT PRIETO‐MÁRQUEZ 《Zoological Journal of the Linnean Society》2010,159(2):435-502
The late Cretaceous hadrosaurids were the most specialized and diverse clade of ornithopod dinosaurs. Parsimony and Bayesian methods were implemented to elucidate the phylogenetic relationships of all hadrosaurid species. Traditional and geometric morphometrics were applied to discover patterns of variation containing phylogenetic information. In total, 286 phylogenetically informative characters (196 cranial and 90 postcranial) were defined and documented: the most extensive character data set ever constructed for hadrosaurid dinosaurs. Of these, 136 characters were used for the first time in phylogenetic analysis of these ornithopods, and 93 were modified from those of other authors. Parsimony and the Bayesian analysis (using the Mk model without the gamma parameter) confirmed the split of hadrosaurids into Saurolophinae and Lambeosaurinae. Saurolophines included a major clade composed of the Prosaurolophus–Saurolophus and the Kritosaurus–Gryposaurus–Secernosaurus subclades. Edmontosaurus and Shantungosaurus were recovered outside the major clade of saurolophines. The Brachylophosaurus clade was recovered as the most basal clade of saurolophines in the parsimony analysis, whereas following the Bayesian analysis it was recovered as the sister clade to the Kritosaurus–Gryposaurus–Secernosaurus clade. These two analyses resulted in a Lambeosaurinae composed of a succession of Eurasian sister taxa to two major clades: the Parasaurolophus clade and the Hypacrosaurs altispinus–Corythosaurus clade. In contrast, the Bayesian analysis using the Mk model with the gamma parameter included, resulted in an unbalanced hadrosauroid tree, with a paraphyletic Saurolophinae, and with the Prosaurolophus clade, Edmontosaurus, and Shantungosaurus as successively closer sister taxa to Lambeosaurinae. Based on the strict reduced consensus tree derived from the parsimony analysis, Hadrosauridae was redefined as the clade stemming from the most recent common ancestor of Hadrosaurus foulkii and Parasaurolophus walkeri. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159 , 435–502. 相似文献
98.
Changes in peripheral clinico-chemical parameters packed cell volume (PCV), hemoglobin (HGB), serum glucose, carbamide-nitrogen (CN), and creatinine were investigated in mice during the development of acute morphine tolerance. Acute morphine treatment (in drug-naive organism) altered the PCV, HGB, serum glucose and CN levels in a naloxone-reversible manner. Acute tolerance developed in PCV, HGB and CN values. The data raise the possibility of a relationship between clinico-chemical and pharmacological tolerance. 相似文献
99.
Mari Cruz Díaz-Barradas María Zunzunegui Fatima Ain-Lhout Juan Jáuregui Said Boutaleb Leonor Álvarez-Cansino Mari Paz Esquivias 《Plant and Soil》2010,337(1-2):217-231
Argania spinosa (the argan tree) is a slow-growing tree endemic of Morocco, growing on semi-arid areas where no other tree species can live. With the aim of predicting temporal changes in A. spinosa woodlands under a probable increase in aridity, we set off to investigate these questions: how do A. spinosa physiological attributes respond to variations in climatic conditions and seasonality, and which is the set of attributes that most affects tree response to environmental conditions? In three study sites, Beni Snassen (North), High-Atlas (Mountain) and Admine Forest in Agadir (Coastal), gas exchange measurements, photochemical efficiency, leaf water potential and different leaf attributes were monitored in February, July and November of 2006. The Mountain site presents the most continental climate. Trees in this site were the most stressed in summer, having the lowest midday leaf water potential values, photochemical efficiency and assimilation rates. We found a Ψmd threshold around -4 MPa, below which stomatal conductance responds linearly to Ψmd. Plants from the North area never reached this threshold during the study period. Although leaf pigments presented a clear seasonal pattern, leaves from Coastal trees exhibit the highest content for each season. The three study sites were separated by two discriminate functions obtained by canonical discriminant analysis. In summer, the Mountain population is separated from the other sites mainly by assimilation rate and Fv/Fm, while in winter transpiration rates and chlorophyll content are the main discriminant variables. Our study shows that A. spinosa trees adjust their physiological status and leaf attributes to environmental conditions allowing plants to thrive under a dry climate. Under a scenario of global change, the distribution of the argan tree likely shifts to milder areas. 相似文献
100.
Ágnes Nyilas 《Nucleosides, nucleotides & nucleic acids》2013,32(9-11):1953-1967
Abstract 5′-O-MMTr-cytosine arabinoside was prepared on a large scale from 5′-O-MMTr-cytidine with diphenyl carbonate via 5′-protected cytidine-2′,3′-carbonate-aracytidine-2′,2-anhydro derivative at a 67 % yield. The synthesis of 1,2-L-dipalmitoyl-snglycerol, 1,2-L-distearoyl-sn-glycerol and 1,2-L-dioleoyl-sn-glycerol described here using 9-fluorenylmethoxycarbonyl (FMOC) group for protection of 3-position of glycerol which can be selectively removed by Et3N treatment on the overall 60–70 % yield based on 1.2,-isopropilidene-sn-glycerol. These glycerols were phosphorylated first with 2-chlorophenyl-phosphoro-bis-triazolide quantitatively1 in order to avoid acyl migration, then the glycerophosphate intermediates were condensed with 2′,3′,N4-trileulinyl-l-β-D-arabinofuranosylcytosine in the presence of 2-mesytilenesulphonyl chloride (MsCl) and 1 -methylimidazole (Melm)-which was used in the coupling of nucleotides2-? in an 85–95 % yield compared with the low yielding diester method of Ryu3. Deblocking was carried out in two steps with tetrabutylammonium fluoride (TBAF) and hydrazine hydrate, producing target compouns (14a, 14b, 14c) at a 50 % yield. 相似文献