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51.
Administration of theophylline to asthmatic children is frequently associated with an adverse influence on their behavior. The efficacy and behavioral effects of the administration of high-dose theophylline (T) and ketotifen (K) in various combinations were evaluated prospectively in a double-blind, placebo controlled study in 55 children with moderately severe perennial asthma. During a baseline period of 2 weeks, theophylline (serum level of 10-20 μg/ml) was administered to all the children. After this period the patients were randomly allocated into four comparable groups. The children were treated during a 12-week period with: T + K-Placebo (T group); T + K (T + K group); half-dose T + K (T/ 2 + K group); or placebo of both T and K (P group). During the 12-week treatment period, as compared to the baseline period, only the three groups of children who received active therapy (T + P, T + K, T/2 + K) showed a similar reduction in the number of days with asthmatic symptomatology, improvement of the total asthmatic symptoms score, and increased PEFR. The behavioral activity of the children (assessed by the Conner's rating scale) improved significantly only in the groups receiving placebo or T/2 + K. The results of this study suggest that a combination therapy of half the recommended therapeutic dose of theophylline with ketotifen can be clinically as effective as therapy with a full dose of theophylline, but with significantly less adverse behavioral effects.  相似文献   
52.
Dimethyl sulfoxide(DMSO) is frequently used as a solvent for antifungal drugs in various studies to determine their MICs. Reports on comparative evaluation of methods for the susceptibility testing of antifungal drugs have shown there is poor agreement among methods. Besides other factors which could cause variability in the results, one important factor might be the effect of DMSO on the growth of fungi. The effect of DMSO on the growth of some species of Candida has been reported in the literature. The present study aimed at determination of the effect of different concentrations of DMSO (0.125 to 10%) on the growth of dermatophytes by agar diffusion method. There was no growth of fungi in 10% DMSO, between 1.25 and 5% there was a rather linear dose-related inhibitory effect on the growth, significantly different from the controls, and below 1% there was a variable effect among the species. DMSO down to 0.25% significantly inhibited the growth of most strains of M. canis. The lower concentrations of DMSO, which apparently do not affect the growth of fungi, may potentiate the effect of antifungal drugs.  相似文献   
53.
54.
The effect of the novel 1,4-dihydronaphthyridine Ca2+ channel inhibitor Goe 5438 (CI-951) on voluntary ethanol consumption was examined in selectively bred alcohol-preferring (P) rats in a free choice two bottle preference test versus water. Intraperitoneally injected Goe 5438 dose-dependently (5, 10 or 20 µmol/kg, twice daily) inhibited ethanol and increased water intake over the 24 h period (injection day). The drug decreased ethanol preference, originally above 90%, by 6%, 19% and 45% at respective doses, on the injection day. That inhibitory effect of the highest dose of Goe 5438 on ethanol preference remained significant also on days 2 and 3 after injections (–51% and –18%, respectively). Goe 5438, in the highest dose, also tended to decrease granulated chow consumption during the injection day only. To further test whether the inhibition of ethanol preference is secondary to decrease in reinforcing properties of ethanol and not due to interference with satiety mechanisms, we compared the effect of two higher doses (10 and 20 µmol/kg, intraperitoneally, twice daily) of Goe 5438 on spontaneous preference for a non-caloric 0.04% saccharin solution in Sprague-Dawley rats. We observed a dose-dependent suppression of preference (by 44% and 58%, respectively) during the injection day, but not the subsequent 24 h period. However, Goe 5438 also significantly alleviated food pellet intake on the injection day. In conclusion, Goe 5438 produces potent and long-lasting inhibition of voluntary ethanol consumption, which may be secondary to attenuation of reinforcing properties of ethanol. Additionally, this particular Ca2+ channel inhibitor appears to have mild anorectic properties which may be conducive to acute suppression of alcohol intake.  相似文献   
55.
Administration of antiserum to thyrotropin-releasing hormone (TRH) into the lateral cerebral ventricle of mice significantly attenuated recovery from hyperglycemia induced by treatment with 2-deoxyglucose but had no effect on the plasma glucose of saline-treated mice. TRH, injected centrally together with the anti-TRH antibody, reversed the effect of the antiserum and blocked the development of hyperglycemia. These findings suggest that activation of TRH neurons in the central nervous system may be a physiological event influencing recovery from hyperglycemia.  相似文献   
56.
Gangliosides of cultured astroglia   总被引:3,自引:0,他引:3  
Cultured astrocytes prepared from newborn rat brain and 13-day-old chick embryonic brain were analyzed qualitatively and quantitatively for ganglioside content. All preparations contained approximately the same total level: 2.4-3.4 micrograms N-acetylneuraminic acid (NeuAc)/mg protein. In contrast, the value for primary cultures of neurons from chick embryonic brain was 5.9. The non-hexosamine-containing species, GM3 and GD3, comprised 75-85% of the total in astroglial cultures, the remainder consisting mainly of structural types other than the gangliotetraose series; choleragenoid assay revealed the latter to be virtually absent or to comprise at most a few percent. Deficiency of gangliotetraose synthesizing ability was indicated by the very low level of UDP-GalNac:GM3 N-acetylgalactosaminyltransferase detected in the cells. Treatment of cultured astrocytes with astroglial growth factor 2 or dibutyryl cyclic AMP caused little if any change in quantity or pattern of gangliosides. The large majority of cells stained in a manner characteristic of astrocytes: positive for glial fibrillary acidic protein, negative for galactosyl ceramides. Staining with cholera toxin and anti-GM1 antibody was essentially negative, as was that with tetanus toxin, A2B5 monoclonal antibody, and antibody to GD3. All evidence thus points to cultured astrocytes of rat and chick brain containing appreciable gangliosides, most of which are GM3 and GD3 with the majority of the remainder comprising structures other than the gangliotetraose type.  相似文献   
57.
PURPOSE: To report the first successful endovascular repair of a non-aneurysmal aortic rupture due to periaortic tumour regression. CASE REPORT: A 58-year-old man developed spontaneous infrarenal aortic rupture following chemotherapy which led to regression of a periaortic mesothelioma that had been diagnosed during explorative laparotomy 11 months earlier. Stent-graft placement was performed with intentional conversion of a bifurcated (Zenith, COOK) into an aorto-uni-iliac system. No complications were encountered during a 40 months follow-up. CONCLUSION: Endovascular repair should be considered as a treatment option in non-aneurysmal aortic rupture.  相似文献   
58.
BACKGROUND: Unsupervised fuzzy clustering (UFC) analysis is a mathematical technique that groups together objects in the multidimensional feature space according to a specified similarity measurement, thereby yielding clusters of similar data points that can be represented by a set of prototypes or centroids. METHODS: Since clinical studies of mental disorders distinguish between affected and unaffected individuals, we designed an inclusion/exclusion criteria (cutoff behavioral criteria [CBC]) approach for animal behavioral studies. The effect of classifying the study population into clearly affected versus clearly unaffected individuals according to behaviors on two behavioral paradigms was statistically significant. RESULTS: Here the raw data from previous studies were subjected to UFC algorithms as a means of objectively testing the validity of the concept of the CBC for our experimental model. The first UFC algorithm yielded two clearly discrete clusters, found to consist almost exclusively of the exposed animals in the one and unexposed animals in the other. The second algorithm yielded three clusters corresponding to animals designated as clearly affected, partially affected, and clearly unaffected. The algorithm for physiological data in addition to behavioral data failed to elicit discrete clusters. CONCLUSIONS: The UFC analysis yielded data that support the conceptual contention of the CBC and lends additional validity to our previous behavioral studies.  相似文献   
59.
Data are limited on seizure recurrence after antiepileptic drug (AED) discontinuation in operated seizure-free patients. We reviewed seizure outcome in patients who came off AEDs after being seizure-free for 2 years following temporal lobe surgery in our center. Thirty-nine (68%) of 57 patients who discontinued AED therapy remained seizure-free. They had a younger age at surgery than the group with seizure recurrence (p=0.01). Earlier surgery may be a favorable predictor for seizure freedom after AED discontinuation.  相似文献   
60.
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