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941.
942.
J. Van Harten P. Van Bemmel M. R. Dobrinska R. K. Ferguson M. Raghoebar 《Biopharmaceutics & drug disposition》1991,12(8):571-576
The influence of concomitant food intake on plasma concentrations of the antidepressant drug fluvoxamine maleate was investigated in a two-way, crossover study design. Eight male and four female healthy, young volunteers received a single oral dose of fluvoxamine maleate (50 mg, tablet) on two occasions: after an overnight fast and immediately after a breakfast. Food did not affect maximum fluvoxamine plasma levels (Cmax), or the time to reach Cmax (tmax). The plasma AUC of fluvoxamine was on average 7 per cent lower in the fed than in the fasted state. It is concluded that the effect of food on the pharmacokinetics of fluvoxamine is negligible. 相似文献
943.
Tetrameric concanavalin A at neutral pH dissociated into the dimer when CuCl2 was added in a concentration range comparable to protomer concentration. This effect of CuCl2 was largely suppressed when NaCl concentration was increased. Neither the conformation of the protein nor its binding activity to 4-methylumbelliferyl α-D-man-nopyranoside was affected on addition of CuCl2. 相似文献
944.
GABA-receptor stimulation enhances norepinephrine-induced polyphosphoinositide metabolism in rat hippocampal slices 总被引:2,自引:0,他引:2
Renato Corradetti Marco Ruggiero Vincenzo P. Chiarugi Giancarlo Pepeu 《Brain research》1987,411(1):196-199
The effect of gamma-aminobutyric acid (GABA)receptor stimulation on norepinephrine (NE)-induced metabolism of polyphosphoinositides (PIPs) was studied in rat hippocampal slices. Inositol phosphates (IPs), PIPs, and phosphatidic acid were measured. NE induced formation of IPs and phosphatidic acid in a dose-dependent manner with an EC50 of 4.5 microM. GABA, 3-aminopropanesulphonic acid (3APS) and muscimol did not affect PIPs breakdown, but they strongly increased (greater than 100%) PIPs metabolism induced by 1 microM NE. Their action was antagonized by bicuculline (10 microM). We discuss the implications of these findings in hippocampal neurotransmission. 相似文献
945.
目的 研究复方罗红霉素氨溴索片中两药在体内是否存在药动学上相互作用。 方法 24 名健康男性志愿者,采用 4 × 4 交叉试验设计,每组 1 人,交叉服用复方罗红霉素氨溴索片、罗红霉素片加氨溴索片、罗红霉素片、氨溴索片,服药后不同时间点取肘静脉血 4~5 mL ,血药浓度采用 HPLC/MS 测定。计算药动学参数,并进行方差分析,以 90% 的可信区间进行药物发生相互作用是否具临床意义的判定。 结果 复方制剂、合用药物以及单用药物药动学参数均无显著性差异。无论是复方或是合用 2 种药物,均未产生有临床意义的药动学相互作用。 结论 罗红霉素氨溴索片中 2 种成分在体内不产生统计学上和临床意义的药动学相互作用。 相似文献
946.
本文从课件制作、体现知识结构性、版面显示、内容表现形式、动画效果、教案的播放顺序、学生接受情况、文件传播的容易等角度出发,对HTML和PowerPoint文件类型的课件进行功能分析和比较,建议把课件做成HTML类型文件. 相似文献
947.
E. C. Melhuish A. Mooney S. Martin E. Lloyd 《Journal of child psychology and psychiatry, and allied disciplines》1990,31(6):849-859
A longitudinal study has followed two-parent families and their first-born child. The families were chosen so that there were three groups of dual-earner families using relatives, childminders and nurseries for day care and one group of single-earner families. At 18 mths of age children in the study were observed in the four types of childcare setting. The data from the detailed observations were used to compare the children's interactional experience. The results indicate marked variation in the quality of children's experiences between different childcare settings. Possible reasons for such variation are discussed. 相似文献
948.
Nathalie Picard Franco Lepore Maurice Ptito Jean-Paul Guillemot 《Brain research》1990,536(1-2):97-104
There are indications in the literature that convergent ipsilateral and contralateral input to the second somatosensory area (SII) may interact. Single unit activity of SII bilateral cells was studied to evaluate the impact of simultaneous bilateral stimulation of the receptive fields (RF) on neural discharge. The cellular responses to unilateral ipsilateral and contralateral, as well as to bilateral stimulation were compared. 22% of bilateral cells showed interaction, usually facilitation. Bilaterally evoked responses were found to be as great as 250% of the strongest unilateral response. Only bilateral responses stronger or weaker than the dominant unilateral response by at least 50% were considered as interactive. The great majority of interactive cells had their RF on the forelimb and were responsive to deep stimulation. The corpus callosum appears to be responsible for part of the observed interaction since in callosotomized cats only 5% of bilateral cells were interactive. A non-callosal ipsilateral pathway must be postulated because both bilaterality and bilateral interaction persist to some degree after callosotomy. A putative role for bilateral interaction in sensory-motor integration is discussed. 相似文献
949.
Yan‐Lin Guo Wenshou Wang Joshua U. Otaigbe 《Journal of tissue engineering and regenerative medicine》2010,4(7):553-564
Incorporation of polyhedral oligomeric silsesquioxanes (POSS) into poly(ester urethanes) (PEU) as a building block results in a PEU/POSS hybrid polymer with increased mechanical strength and thermostability. An attractive feature of the new polymer is that it forms a porous matrix when cast in the form of a thin film, making it potentially useful in tissue engineering. In this study, we present detailed microscopic analysis of the PEU/POSS matrix and demonstrate its biocompatibility with cell culture. The PEU/POSS polymer forms a continuous porous matrix with open pores and interconnected grooves. From SEM image analysis, it is calculated that there are about 950 pores/mm2 of the matrix area with pore diameter size in the range 1–15 µm. The area occupied by the pores represents approximately 7.6% of the matrix area. Using mouse embryonic stem cells (ESCs), we demonstrate that the PEU/POSS matrix provides excellent support for cell proliferation and differentiation. Under the cell culture condition optimized to maintain self‐renewal, ESCs grown on a PEU/POSS matrix exhibit undifferentiated morphology, express pluripotency markers and have a similar growth rate to cells grown on gelatin. When induced for differentiation, ESCs underwent dramatic morphological change, characterized by the loss of clonogenecity and increased cell size, with well‐expanded cytoskeleton networks. Differentiated cells are able to form a continuous monolayer that is closely embedded in the matrix. The excellent compatibility between the PEU/POSS matrix and ESC proliferation/differentiation demonstrates the potential of using PEU/POSS polymers in future ESC‐based tissue engineering. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
950.
激光汽化活体生物组织的传热过程分析 总被引:3,自引:0,他引:3
目的:研究激光汽化生物活体组织的传热过程及其影响因素,方法:基于血液灌注率温度依赖型Pennes生物传热方程,建立激光与生物活体组织热相互作用的一般模型,研究组织表面发生汽化相变,中间组织出现热凝结,内层组织发生温升的过程,由此探讨组织中的激光传输特性,以及血液灌注率和边界冷却等因素的影响情况。结果:通过数值计算,得出活体组织表面汽化速度及内部温度分布,研究表明,活体组织对不同激光的吸收能力,血液灌注率与边界冷却放松择组织汽化速度,组织凝结过程及温度分布有显著影响。结论:该模型可用于预测激光汽化蚀除组织的过程,分析结果对激光临床应用具有理论指导意义。 相似文献