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Infants who ingest high amounts of fluoride can be at risk of dental fluorosis. The authors analyzed the fluoride concentration of 238 commercially available infant foods. Fluoride concentrations ranged from 0.01 to 8.38 micrograms of fluoride per gram, with the highest fluoride concentrations found in infant foods containing chicken. Infant foods, especially those containing chicken, should be considered when determining total fluoride intake. 相似文献
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Ten groups of 14 immunosuppressed NMRI-mice (nu/nu) were raised and kept under germ-reduced conditions. The control animals were fed a germ-reduced diet, nine other groups received the same diet with selegiline (CAS 14611-51-9, Deprenyl) or lipoic acid (thioctic acid, CAS 62-46-4) admixed at various amounts. The 50% survival rate, the total life span of each group and the areas under the curves were determined to evaluate life expectancy as compared to the controls. The racemate of lipoic acid at high dosage (350 mg/kg body weight) reduced the life span significantly. The S(-)-enantiomer of lipoic acid (75 mg/kg body weight) increased the 50% survival rate, whereas the physiologic R(+)-enantiomer (9 mg/kg body weight) expanded the total life span of its group. Alteration of only one out of three parameters was not considered significant. All other groups except for one did not differ from controls: only animals which obtained 75 micrograms selegiline per kg of body weight and per day exerted increased life expectancies by all three parameters. This group exhibited also in statistical evaluation a significantly (p < 0.05) prolongated survival time up to about 200% as compared to the control animals. 相似文献
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To evaluate the efficacy and safety of low dose (10 mg) pravastatin in hypercholesterolemic, hypertensive elderly subjects undergoing antihypertensive treatment, a randomized, double-blind, placebo-controlled 6-month trial was conducted. The subjects had a total plasma cholesterol of at least 250 mg/dL and had been, for at least 3 months, consuming a standard lipid-lowering diet (American Heart Association Step 1 Diet). Sixty elderly hypertensive patients randomly received placebo (n = 30) or pravastatin (n = 30) treatment. The dosage consisted of 10 mg of pravastatin daily during the 6-month trial. Over that period, in the pravastatin group, plasma levels of total cholesterol and LDL-cholesterol significantly (P < .01) dropped (-20% and -25%, respectively) compared to the placebo group. The plasma level of HDL-cholesterol increased (+5%) while triglycerides slightly decreased (-8%) (P < .05). No serious side effects occurred, and pravastatin was generally tolerated. Fasting hyperinsulinemia (11.0 +/- 0.8 v 9.3 +/- 0.7 microU/mL; P = .06) also improved, although not significantly, after 6 months of pravastatin therapy. Results from this study confirmed that a low dose (10 mg) of pravastatin daily is a safe and effective method of reducing plasma total and LDL-cholesterol in hypercholesterolemic, hypertensive elderly patients who are on concurrent antihypertensive drug therapy. 相似文献
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TS Frank RE Bartos HK Haefner JA Roberts MD Wilson GP Hubbell 《Canadian Metallurgical Quarterly》1994,7(1):3-8
Eight anticonvulsant drugs-including clonazepam, diazepam and phenobarbital-were tested for their effects on GABA-stimulated chloride uptake in rat cerebral cortical microsacs (unfiltered synaptoneurosomes). "Mid" and "high" therapeutic concentrations were screened, and, if significant enhancement was found, full concentration-response tests were done. In the initial screens, enhancement of GABA-stimulated uptake was found only with phenobarbital, clonazepam and diazepam. In subsequent concentration-response tests, the effects of phenobarbital were found to occur throughout the range of normal, anticonvulsant concentrations, whereas the effects of clonazepam and diazepam were observed only above the concentrations normally used for the chronic control of seizures or anxiety. These data suggest that phenobarbital's anticonvulsant effects are mediated via the GABAA receptor complex, but that the low-dose effects of the benzodiazepines may be mediated via some other mechanism. 相似文献
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Excitatory amino acid overstimulation of neurons can lead to a marked rise in cytoplasmic Ca2+ concentration ([Ca2+])i) and be followed by neuron death from hours to days later. If the rise in [Ca2+]i is prevented, either by removing Ca2+ from the extracellular environment or by placing Ca2+ chelators in the cytosol of the stimulated cells, the neurotoxicity associated with excitotoxins can be ameliorated. We have recently shown that neurons infected with a herpes simplex virus amplicon vector expressing cDNA for calbindin D28k responded to hypoglycemia with decreased [Ca2+]i and increased survival relative to controls. We now report that vector-infected neurons respond to glutamatergic insults with lower [Ca2+]i than controls and with increased survival. Infected neurons exposed to sodium cyanide did not respond with lower [Ca2+]i than controls, nor did they demonstrate increased survival postinsult. We examine these results in light of our earlier report and in the context of the potential of vectors like this for neuronal gene therapy. 相似文献