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61.
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Gunnel Alfredsson Göran Sedvall Frits-Axel Wiesel 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1979,164(2):187-193
A high-performance liquid chromatographic method for the analysis of sulpiride, N-ethyl-2-(2-methoxy-5-sulphonamido-benzamido-methyl)-pyrrolidine, in body fluids is described. A structurally related compound, N-ethyl-2-(2,4-dimethoxy-benzamido-methyl)-pyrrolidine, was used as internal standard.A fluorescence detector with excitation maximum at 299 nm and emission maximum at 342 nm was used for the quantitation. The detection limit was about 10 ng/ml in serum and cerebrospinal fluid and about 200 ng/ml in urine. The experimental error was 5–10% in the concentration range 25–100 ng/ml. Some preliminary data from a pharmacokinetic study in healthy volunteers are presented. The half-life for sulpiride in serum was about 8 h. Sulpiride was also measured in cerebrospinal fluid from five drug-treated psychotic patients. 相似文献
63.
A simulation method to interpret electron spin resonance (ESR) of spin labelled amphiphilic molecules in oriented phosphatidylcholine multibilayers in terms of a restricted motional model is presented. Order and motion of the cholestane spin label (3-spiro-doxyl-5α-cholestane) incorporated into egg yolk phosphatidylcholine, dipalmitoylphosphatidylcholine and dimyristoylphosphatidylcholine, pure and in mixture with cholesterol, were studied at various termperatures. With egg yolk phosphatidylcholine identical sets of motional parameters were obtained from simulations of ESR spectra obtained at three microwave frequencies (X-, K- and Q-band). With dipalmitoylphosphatidylcholine and dimyristoylphosphatidylcholine analyses of the spectra show that phase transitions occur in samples containing up to 30 mol % cholesterol. The activation energy for the motion of the spin label is about three times larger above than below the phase transition, indicating a more collective motion in the liquid crystalline state than in the gel state. In the liquid crystalline state the activation energy is larger in the pure phosphatidylcholines than with cholesterol added. Additions of cholesterol to egg phosphatidylcholine induces a higher molecular order but does not appreciably affect correlation times. This is in contrast to dipalmitoylphosphatidylcholine where both order and correlation times are affected by the presence of cholesterol. The activation energies follow the same order as the transition temperatures: dipalmitoylphosphatidylcholine > dimyristoylphosphatidylcholine > egg yolk phosphatidylcholine, suggesting a similar order of the cooperativity of the motion of the lipid molecules. Magnetic field-induced effects on egg phosphatidylcholine multibilayers. 相似文献
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Cerebral arterio-venous differences of homovanillic acid (HVA) and cerebral blood flow were measured in 24 patients, 6 adults and 18 children, anaesthetized by different techniques. A statistically significant release of HVA from the brain (p < 0.001) was demonstrated in five children anaesthetized by barbiturate, nitrous oxide and droperidol/fentanyl. The release rate was 509 pmoles HVA/100 g brain tissue/minute - corresponding to approximately 1.3 mg HVA/24 hours from the whole brain. 相似文献
66.
3-Indole carboxylic acid (ICA) has been characterized as an endogenous constituent of Pinus sylvestris needles. Quantitative estimates of 3-indole acetic acid (IAA) and ICA, corrected for both sample losses and the conversion of IAA to ICA occurring during purification, indicate that Pinus needles contain 24.5 ± 6.5 ng IAA/g and 2.3 ± 0.4 ng ICA/g. 相似文献
67.
Functional redundancy of multiple forest taxa along an elevational gradient: predicting the consequences of non‐random species loss
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Akira S. Mori Takayuki Shiono Takashi F. Haraguchi Aino T. Ota Dai Koide Takayuki Ohgue Ryo Kitagawa Ryo Maeshiro Toe Toe Aung Taizo Nakamori Yusuke Hagiwara Shunsuke Matsuoka Anzu Ikeda Takuo Hishi Satoru Hobara Eri Mizumachi Andreas Frisch Göran Thor Saori Fujii Takashi Osono Lena Gustafsson 《Journal of Biogeography》2015,42(8):1383-1396
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Göran Stenlid 《Phytochemistry》1976,15(6):911-912
The flavonoids quercetagetin, gossypetin and scutellarein 7-glucoside which have o-dihydroxyl groups in the A ring inhibit indole-3-acetic acid oxidase. Since scutellarein 7-glucoside has no such grouping in the B-ring it is clear that it is the hydroxyls in the A-ring that cause the inhibition. The presence of o-dihydroxyls in the A-ring also decreases the inhibitory effect upon ATP formation in mitochondria. 相似文献