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981.
982.
Penstemon pinorum, from the Pine Valley Mountains of southwestern Utah, is described and illustrated. It is compared morphologically and ecologically to other members of sectionCristati. 相似文献
983.
Diego A. Golombek Esteban Escolar Leila J. Burin Marí a G. De Brito S nchez Diego Fern ndez Duque Daniel P. Cardinali 《Chronobiology international》1992,9(2):124-131
We endeavored to determine whether three behavioral effects of melatonin in rodents, i.e., depression of locomotor activity in hamsters, analgesia in mice, and impairment of 3-mercaptopropionic acid (3-MP) convulsions, exhibited the time dependency known to occur for several neuroendocrine effects of the hormone. Activity was monitored and registered by means of an optical acto-meter, and analgesia was assessed by the hot-plate procedure. Locomotor activity, analgesia, and seizure susceptibility were maximal at the beginning of the scoto-phase and minimal at noon. The effects of melatonin on the three parameters peaked at early night. The administration of the benzodiazepine antagonist fluma-zenil, although unable by itself to modify locomotor activity, pain, or seizure threshold, blunted the activity of melatonin. These results suggest that the time-dependent effects of melatonin on specific rodent behaviors may be mediated by central synapses employing 7-aminobutyric acid (GABA) as an inhibitory transmitter. 相似文献
984.
Leila M. Lopes-Alves Lucia Mendonça-Previato Bernard Fournet Pierre Degand José O. Previato 《Glycoconjugate journal》1992,9(2):75-81
-Elimination of peptidorhamnomannans purified from yeast-like and mycelial phases ofSporothrix schenckii released neutral and acidic reduced oligosaccharides that were O linked to serine and/or threonine. Man-(1–2)Man-ol, Rha(1–3)Man(1–2)Man-ol, Rha(1–4)GlcA(1–2)Man(1–2)Man-ol, and Rha(1–4)[Rha(1–2)] GlcA(1–2)Man(1–2)Man-ol were characterized based on methylation analysis, proton magnetic resonance and fast atom bombardment mass spectrometry.Abbreviations FAB
fast atom bombardment
- GLC
gas liquid chromatography
- GlcA
d-glucopyranosyluronic acid
- Man
d-mannopyranose
- Man-ol
d-mannitol
- MS
mass spectrometry
- NMR
nuclear magnetic resonance
- Rha
l-rhamnopyranose 相似文献
985.
Leila V. Alegrio Raimundo Braz Fo. Otto R. Gottlieb J.Guilherme S. Maia 《Phytochemistry》1981,20(8):1963-1965
A re-examination of the trunk wood of Licaria armeniaca led to the isolation of 6,7-dimethoxycoumarin, 1,2,3-trimethoxy-7-oxoaporphine (tri-O-methylmoschatoline, 2e-(3,4,5-trimethoxyphenyl)-6e-(3,4-dimethoxyphenyl)-3,7-dioxabicyclo [3.3.0]octan (magnolin) and a novel neolignan (7S,8R,1′S,2′S,3′S)-2′-acetoxy-1′-allyl-3′,5′-dimethoxy-8-methyl-7-piperonyl-bicyclo [3.2.1]-oct-5′- en-4′-one. 相似文献
986.
Leila Risteli Juha Risteli Annegret Ihme Thomas Krieg Peter K. Müller 《Biochemical and biophysical research communications》1980,96(4):1778-1784
Normal and Ehlers-Danlos syndrome type VI human skin and cornea fibroblasts were assayed for lysyl hydroxylase activity using two different collagen types as substrates. The enzyme from normal fibroblasts hydroxylated type I collagen more readily than type IV collagen. In the diseased cells the enzyme activity was significantly reduced, and the residual activity was preferentially directed towards type IV collagen. This suggests the existence of isoenzymes of lysyl hydroxylase or an alteration in the Ehlers-Danlos syndrome type VI that affects the binding of type I collagen more than that of type IV collagen. 相似文献
987.
A new species,Sphaeromeria ruthiae, from Zion National Park, and three new combinations,S. martirensis,S. compacta, andS. potentilloides var.nitrophila, are presented. Morphological and anatomical evidence is used to support the recognition ofSphaeromeria as distinct fromTanacetum. 相似文献
988.
989.
Hadia Elhadi Slama Amor Romdhane Leila Cheikh M’Hamed Hatem Fahej Mohamed Ali Saed Radhouane Leila 《Journal of Plant Growth Regulation》2023,42(1):304-318
Journal of Plant Growth Regulation - Salt stress is a main factor limiting the production and productivity of wheat in arid and semi-arid zones. The objectives of this study were to compare the... 相似文献
990.
Shaida Mahmoudi Mohamad Javad Chaichi Mojtaba Shamsipur Ome Leila Nazari Abdolraouf Samadi-Maybodi 《Luminescence》2023,38(10):1711-1719
Atropine (AT) is an anticholinergic drug. AT is abundantly in Datura plant seeds. Fe3O4@Zn/Mg MOF (Fe3O4@MOF) composite was synthesized. The compound had a high peroxidase-like activity in a chemiluminescence (CL) reaction. Addition of AT quenched CL. The linear range and limit of detection were 5–600 μg L−1 and 2 × 10−2 μg L−1. This method is fast, reversible, and selective, without biodegradability effects, high accuracy, and precision for measuring AT in the Datura plant. 相似文献