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1.
The kinetics of a single i. v. dose of theophylline given either alone or with flumequine was studied in eight healthy volunteers. No statistically significant differences were observed in the pharmacokinetic parameters of theophylline (volume of distribution, elimination half-life, AUC, plasma clearance) following the two treatments.Pretreatment for 5 days with oral flumequine (400 mg, three times daily) had no significant effect on the disposition of a single i. v. dose of theophylline in healthy volunteers.  相似文献   
2.
Apomorphine-induced blinking and yawning in healthy volunteers.   总被引:2,自引:0,他引:2       下载免费PDF全文
Yawning and spontaneous blink rate (SBR) are two physiological reflexes which have been incompletely examined but one neurobiological step of these two behaviours seems, at least in part, dopamine-dependent. The reference dopaminergic agonist, apomorphine hydrochloride (0.5, 1, and 2 micrograms kg-1 s.c.), was compared with a placebo in a double-blind latin-square design, and was shown to induce yawning and increase SBR in a population of eight healthy volunteers. These two behavioral effects were not dose-related. The individual SBR differences were correlated with the individual number of yawns for all the four treatments at the 10-30 min interval. Thus, parallel yawning and SBR behaviour suggests a similar pharmacological mechanism. Apomorphine-induced yawning and blinking may be therefore of use in the evaluation of central dopaminergic pathways in man.  相似文献   
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We report gait abnormalities with exaggerated support against gravity in a 76 year-old woman. This exaggeration, and its demonstration by ankle dorsiflexion in supine position, was first described by Rademaker and Garcin (1933) as probably resulting from cerebellar and brainstem lesions. In the present case, quantitative analysis of locomotion showed a strong reduction in both stride duration and stride length. There was an increased variability between two consecutive locomotor cycles and a large increase in both stance duration and relative double-support duration. Electromyography clearly showed leg hypertension following ankle dorsiflexion, contrasting with normal leg mobility in the supine patient. This suggested that reflexive antigravity support abnormalities could explain this pattern of locomotor disabilities, differentiating them from other kinds of "marche à petits pas". The present case was associated with bilateral pallidal calcifications, suggesting an involvement of the basal ganglia in support reaction against gravity and in control of adequate postural muscle tone necessary for locomotion.  相似文献   
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Three small peptides with a typical cysteine-rich domain (TFF or P-domain) display a specific folding structure (trefoil); they are abundantly expressed on mucosal surfaces of normal and neoplastic gastrointestinal tissues. This epithelial location coincides with mucin secretion and, although not proven beyond doubt, this association is suggestive of their function in maintenance of surface integrity. Using normal colon epithelium, premalignant lesions and tumor samples and specific antibodies we studied expression of these peptides in colorectal carcinomas. RT PCR was performed to extend the sensitivity of the assays. While coexpression of pS2, hITF, MUC1 and MUC2 was demonstrated, MUC5 was absent and no simultaneous activity of pS2 and SML1 (as in gastric mucosa and carcinoma) was noted in rectal tumors. Actively transcribed and expressed cytokeratin 20 and GAPDH were used as experimental controls for immunostaining and RT-PCR, respectively.  相似文献   
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Enoximone (a type III-selective phosphodiesterase inhibitor) and dobutamine (a beta-receptor agonist) are positive inotropic drugs frequently used in the postoperative management of coronary bypass surgery. The purpose of this study was to characterize their relaxant effects on the human internal mammary artery (IMA) and the gastroepiploic artery (GEA) and to test the hypothesis that their combination may have greater than additive relaxant effects. In organ baths, the relaxant effects of enoximone and dobutamine were tested on rings of IMA (n = 86) precontracted with U46619 (a thromboxane A2 mimetic), norepinephrine (NE), or KCl. The relaxant effects of dobutamine and enoximone also were tested on rings of GEA (n = 42) precontracted with U46619 and NE. The effect of the combination of enoximone and dobutamine were tested on rings of IMA (n = 24) precontracted with U46619 or NE. With respect to maximal relaxations induced by papaverine (10(-4) M), enoximone (< or =10(-3) M) caused full relaxations of IMA precontracted with NE, U46619, or KCI. Dobutamine (< or =10(-3) M) caused full relaxations of IMA precontracted with NE or KCI but only 46% (95% CI, 27-65) relaxation in the rings precontracted with U46619. Similar patterns of relaxation were observed in GEA rings, with dobutamine inducing partial relaxation in GEA precontracted with U46619. The pD2 values of enoximone and dobutamine were both significantly lower in segments precontracted with U46619. The in vitro threshold relaxant concentrations were in the upper limits or over the range of therapeutic plasma concentrations. The relaxant effect of the combination was significantly more important than the theoretic additive effect in IMA contracted with U46619 or NE. Enoximone and dobutamine are potent in vitro vasodilators but exert weak relaxant effects in IMA and GEA at concentrations in the therapeutic range. There is, however, a greater than additive vasorelaxant effect of the combination, suggesting that the vasorelaxant effect of the combination, in addition to the additive inotropic effect, may be beneficial to patients undergoing coronary bypass grafting.  相似文献   
10.
Specific chromosomal losses have been reported for various human tumors. We have now investigated ten cases of urothelial carcinoma and observed genomic alterations by a new method allowing detection of chromosomal losses directly in the tissue section. In 6 out of 8 male carcinomas, the Y-chromosome was lost either in single cells and isolated areas or in extended regions of the tumor sample. Presence of chromosome 1 served as an internal control. This new in situ method allows studies of chromosomal alterations in relation to their tumor topology and the observations constitute the first report on such localised tumor-specific genomic changes.  相似文献   
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