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21.
Results of a recent study have demonstrated that exposure to multiple ethanol concentrations and repeated ethanol deprivation periods in Indiana ethanol-preferring (P) rats resulted in the development of an alcohol deprivation effect (ADE; the temporary increase in voluntary ethanol intake after a period of deprivation from ethanol) characterized by consumption of intoxicating amounts of ethanol. The current study was designed to possibly extend these results to Sardinian alcohol-preferring (sP) rats, generated with the same selective program previously used for P rats. To this aim, ethanol-naive sP rats were exposed initially to the home cage four-bottle choice [10%, 20%, and 30% (vol./vol.) ethanol solutions and water] for eight consecutive weeks. Subsequently, rats were divided into two groups: The first group had continuous access to the four-bottle regimen (nondeprived rats), and the second group was exposed to five cycles of 14-day periods of deprivation from ethanol and 14-day periods of reexposure to the four-bottle regimen. An ADE developed after each deprivation period. However, the extra intake of ethanol was limited to the first hour of each reaccess period. Magnitude of ADE did not change with repeated periods of deprivation. However, a shift in preference toward the two highest concentrations of ethanol solutions was evident from the first reexposure to ethanol and was maintained throughout the study. These results provide further evidence on the heterogeneity of ethanol-drinking behavior among rat lines selectively bred for high ethanol preference and consumption.  相似文献   
22.

Background  

Long-term morphofunctional outcome may vary widely in surgical anterior left ventricular wall restoration, suggesting variability in post-surgical remodeling similar to that observed following acute myocardial infarction. The aim of this pilot study was to demonstrate that surgical restoration obtained with a particular shape of endoventricular patch leads to steady morphofunctional ventricular improvement when geometry, volume and residual akinesia can be restored as normal as possible.  相似文献   
23.
OBJECTIVE: The present study tested the hypothesis that cortical electroencephalographic (EEG) rhythms. change across normal elderly (Nold), mild cognitive impairment (MCI), and Alzheimer's disease (AD) subjects as a function of the global cognitive level. METHODS: Resting eyes-closed EEG data were recorded in 155 MCI, 193 mild AD, and 126 age-matched Nold subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. RESULTS: Occipital delta and alpha 1 sources in parietal, occipital, temporal, and 'limbic' areas had an intermediate magnitude in MCI subjects compared to mild AD and Nold subjects. These five EEG sources presented both linear and nonlinear (linear, exponential, logarithmic, and power) correlations with the global cognitive level (as revealed by mini mental state examination score) across all subjects. CONCLUSIONS: Cortical EEG rhythms change in pathological aging as a function of the global cognitive level. SIGNIFICANCE: The present functional data on large populations support the 'transitional hypothesis' of a shadow zone across normality, pre-clinical stage of dementia (MCI), and AD.  相似文献   
24.
A comparison was made of different culture media and procedures for detection of Serratia marcescens from faecal, pharyngeal and ocular swabs collected from 213 neonates. MacConkey agar and MacConkey agar with sorbitol (1%) and/or colistin (200 i.u./ml) were used both for primary isolation and after enrichment using Mossel Enterobacteriaceae broth with colistin (200 i.u./ml). The use of MacConkey agar supplemented with colistin for primary isolation improved considerably the isolation rate of S. marcescens from faecal swabs but not from pharyngeal swabs; the number of ocular isolations were insufficient to demonstrate differences between procedures. Moreover the enrichment procedures consistently increased the number of S. marcescens isolates especially from pharyngeal and ocular swabs. Use of sorbitol made detection of S. marcescens from clinical specimens easier and time- and cost-efficient.  相似文献   
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26.
High doses of BHA cause hyperplasia and subsequent neoplasia in the rodent forestomach and can inhibit gastric prostaglandin (PG) synthesis in vitro. This paper examines the hypothesis that BHA induced forestomach hyperplasia occurs in response to a reduction of gastric mucus, with consequent irritation of the forestomach. This could result from inhibition of the formation of the PG's which mediate the synthesis and release of protective mucus. Groups of 10 rats received 0 or 2% BHA in the diet for 1 or 3 weeks and a positive control group was fed a diet containing indomethacin (3.5 mg/kg), a potent inhibitor of PG synthesis. After 1 week BHA caused focal erosion and ulceration of the forestomach consistent with an irritant effect, but 2 weeks later the epithelium was healed, thickened and markedly hyperplastic. Histochemical staining for mucus showed that the development of forestomach hyperplasia was associated with increased amounts of gastric and duodenal mucus and increased numbers of serotonergic-cells in the gastric and duodenal epithelium. In contrast, indomethacin caused a marked reduction in both gastric and Brunner's gland mucus. Neither BHA nor indomethacin exerted an effect on one specific type of mucus (viz: neutral, acidic or mixed) in the stomach. These results do not support the hypothesis that forestomach hyperplasia arises from an inhibition of either the synthesis or release of gastric mucus. It is possible that the increased numbers of serotonergic-cells are related to the initial ulcerative, or subsequent hyperplastic response.  相似文献   
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28.
Constituents of Fagaceae (Cupuliferae), XIX: Triterpene Saponins and Acylated Flavonoids from Quercus robur L. var. stenocarpa Beck. In addition to four known glycosides from leaves of Quercus robur L. var. stenocarpa Beck. a new triterpene saponin has been isolted and identified as 28-β-d-glucopyranosyl ester of the 2α,3β,19α-trihydroxy-olean-12-ene-24,28-dioic acid ( I ).  相似文献   
29.
To determine whether prenatal thiamine deficiency, a frequent concomitant of alcoholism, reduces the response to ethanol during adulthood in the rat as does ethanol exposure in utero (Abel et al. 1981), pregnant Sprague-Dawley rats received either control or thiamine deficient diets together with daily injections of the thiamine antagonist pyrithiamine. At 7 months of age, male offspring were exposed to precisely regulated ethanol vapor concentrations in an inhalation chamber for 24 h and blood ethanol concentrations (BECs) and ethanol-induced intoxication were determined. Prenatally thiamine deficient rats and controls were indistinguishable in terms of appearance, body and liver weights, and the ratios of liver to body weight and brain to liver weight. However, total body water was significantly greater, and BECs and behavioral impairment were decreased, in the experimental rats. These findings indicate that prenatal thiamine deprivation is associated with reduced pharmacologic effect of ethanol as a result of increases in its volume of distribution and rate of metabolism.  相似文献   
30.
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