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Alcohol use, which typically begins during adolescence and differs between males and females, is influenced by both the rewarding and aversive properties of the drug. One way adolescent alcohol use may modulate later consumption is by reducing alcohol's aversive properties. Here, we used a conditioned taste aversion (CTA) paradigm to determine if pre-exposure to alcohol (ethanol) during adolescence would attenuate ethanol-induced CTA assessed in adulthood in a sex-dependent manner. Male and female Long-Evans rats were given intraperitoneal (i.p.) injections of saline or 3.0 g/kg ethanol in a binge-like pattern during postnatal days (PD) 35-45. In adulthood (>PD 100), rats were given access to 0.1% saccharin, followed by saline or ethanol (1.0 or 1.5 g/kg, i.p.), over four conditioning sessions. We found sex differences in ethanol-induced CTA, with males developing a more robust aversion earlier in conditioning. Sex differences in the effects of pre-exposure were also evident: males, but not females, showed an attenuated CTA in adulthood following ethanol pre-exposure, which occurred approximately nine weeks earlier. Taken together, these findings indicate that males are more sensitive to the aversive properties of ethanol than females. In addition, the ability of pre-exposure to the ethanol US to attenuate CTA is enhanced in males compared to females.  相似文献   
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The justification for a neuroblastoma screening program has been discussed controversially. The analysis of 701 patients of the German neuroblastoma trials NB 79, 82, and 85 provides additional information on this subject. The basis of our investigation was the good prognosis of stage I and II patients (92% survival 5-10 years after diagnosis) compared with 66% in stage III and 11% in metastatic disease. The correlation of age and stage (p less than 0.0001), a median progression time of 14.6 months (range 3.4-33.5 mo) from localized to metastatic disease as observed in 18 patients, the high incidence of asymptomatic diseases in stages I (49%) and II (30%) patients and the cost-benefit estimation arguments in favor of a screening program. The key problem for the lab part is the lower incidence of abnormal catecholamine metabolite excretion in stage I and II patients. The origin of 89% of metastatic disease from intraabdominal sites suggests that ultrasonography may be of additional value.  相似文献   
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The effect of different diets on the percentage content of long-chain polyunsaturated fatty acids (LCP; metabolites of linoleic and alpha-linolenic acids) in plasma lipids was studied in 29 premature infants on days 4 and 21 of life. Eleven infants were fed human milk which supplies LCP (1.7% of the fatty acids), 10 a commercially available milk formula without LCP, and 8 a new formula enriched with LCP of the omega-6 and the omega-3 series (0.5% LCP). LCP values in plasma lipids remained stable during the observation period in infants fed human milk. In contrast, LCP decreased markedly in plasma lipids of infants fed the conventional formula. Since the precursor fatty acids linoleic and alpha-linolenic acids were high in their diet and plasma, this finding indicates that premature infants have a limited capacity for LCP biosynthesis and may require their dietary supplementation. Infants fed the LCP enriched formula had significantly higher LCP proportions in plasma lipids than infants given the conventional formula, but less than infants fed human milk. Our results demonstrate that small concentrations of dietary LCP have marked effects on plasma lipid composition, particularly on phospholipids, suggesting that dietary LCP are preferentially channelled into structural lipids. We conclude that the essential fatty acid status of formula-fed premature infants can be improved by a supplementation of omega-6- and omega-3-LCP.Abbreviation LCP long-chain polyunsaturated fatty acids  相似文献   
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In a double-blind, placebo-controlled, crossover trial, we investigated the effects of the prokinetic drug cisapride in patients with cystic fibrosis and chronic recurrent distal intestinal obstruction syndrome (DIOS). After a baseline period, 17 patients (12.9 to 34.9 years; 12 boys) received, in random order, cisapride (7.5 to 10 mg) and placebo three times daily by mouth, each for 6 months. Gastrointestinal symptoms (flatulence, abdominal pain, fullness, abdominal distension, nausea, anorexia, heartburn, diarrhea, vomiting and regurgitation) were scored three times monthly and physical examinations assessed. At baseline and at each 6-month period, assessment included food intake for 7 days, 3-day stool collection, pulmonary function tests, and abdominal radiographs. During cisapride therapy compared with placebo, there were significant reductions in flatulence (p less than 0.005), fullness, and nausea (p less than 0.05). Patients with the worst symptom scores benefited most from cisapride. With cisapride, 12 patients felt better and three worse (p less than 0.05); physicians judged 11 patients improved and two worse (p less than 0.05). No side effects were noted. There were no significant differences between cisapride and placebo periods in nutritional status, x-ray scores, pulmonary function, food intake (fat, protein, calories), stool size and consistency, and fecal losses of fat, bile acids, chymotrypsin, and calories. For acute episodes of DIOS, intestinal lavage was needed 6 times in 4 patients during treatment with cisapride, and 11 times in 6 patients receiving placebo. In comparison with unselected patients with cystic fibrosis and pancreatic insufficiency who were receiving enzyme supplements and who had no distal intestinal obstruction, fecal fat losses (percentage of intake) were almost twice as high in the study group with DIOS (31.2 +/- 20.6% vs 16.2 +/- 17.6%; p less than 0.01). We conclude that in the dosage used, long-term treatment with cisapride appears to improve chronic abdominal symptoms in patients with cystic fibrosis and DIOS, but fails to abolish the need for intestinal lavage. Cisapride treatment had no effect on digestion and nutritional status of cystic fibrosis patients with pancreatic insufficiency.  相似文献   
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In patients with severe genetic hypercholesterolemia, therapeutic reduction of elevated serum total cholesterol and LDL cholesterol should begin in early childhood to lower the risks of cardiovascular disease later in life. We evaluated the effects of outpatient therapy with diet alone and with combined diet and drug therapy in children and adolescents with hypercholesterolemia of apparent dominant inheritance. Serum lipid values before and during dietary treatment were available in 35 patients (mean age at start of treatment 7.9 years, range 2.0-17.6 years) followed for an average duration of 17.5 months (range 4-70 months). A comparison between untreated state and combined therapy with diet and cholestyramine was possible in 14 patients (mean age 8.6 years, range 2.4-17.0 years) followed for 27.9 months (range 4-97 months). Dietary modification achieved by repeated counseling and training lowered serum total cholesterol by mean (+/- SE) 11.7 +/- 1.9% (p < 0.0001) and LDL cholesterol by 17.3 +/- 3.5% (p < 0.0001). However, five of 35 patients did not show an appreciable effect of therapy (cholesterol reduction < 5%), possibly because of non-compliance. Diet combined with cholestyramine in an average dose of 0.36 g/kg body weight/day reduced total cholesterol by 33.0 +/- 2.4% (p < 0.0001) and LDL cholesterol by 37.5 +/- 4.3% (p < 0.0001) and was effective in all patients. Both forms of treatment had no effect on serum triglycerides and HLD cholesterol. No serious side effects were noted, and percentile values for weight and height remained unchanged in all but three obese children.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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