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991.
Urinary 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) were determined in 44 young adult migraine patients (35 women, 9 men) between attacks and in 33 healthy controls (23 women, 10 men). HVA excretion was equivalent in all groups. 5-HIAA was unaltered in men but was significantly decreased in female migraine patients when compared with their sex-matched controls (-31%, p less than 0.01). No relationship was found between 5-HIAA excretion and the various characteristics of migraine, such as the time that had elapsed since the last attack and the presence or absence of oral contraception. The relatively marked decrease in 5-HIAA excretion in female migraine patients can hardly be accounted for by a reduction in either neuronal or platelet serotonin metabolism alone. A reduction in the intestinal contribution to urinary 5-HIAA might be the crucial factor.  相似文献   
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995.
The objective of the present study was to compare two configurations of the hepatocyte model namely suspensions (SH) and conventional primary cultures (CPC) for their ability to predict the hepatic clearance in vivo in the rat and, to investigate the impact of serum on the prediction accuracy. The metabolic competences of several cytochrome P450 isoenzymes were investigated both in CPC and SH in the presence or absence of serum. Under the same conditions, the in vitro intrinsic clearance of six test compounds metabolised by a variety of phase I and phase II enzymes (antipyrine, RO-X, mibefradil, midazolam, naloxone and oxazepam) were derived from Vmax/Km scaled up to the corresponding in vivo hepatic metabolic clearance. CYP activities were shown to be stable in both CPC and SH for up to 6 h of incubation, except for the CYP 3A1 activity that decreased in CPC even in the presence of serum. Moreover, the clearances predicted from SH in the presence of serum were closer to the in vivo values than those obtained from CPC. SH represent a convenient model to assess the hepatic metabolism of xenobiotics, the presence of serum in the incubation medium significantly improved in several instances the quality of the predictions.  相似文献   
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997.
BACKGROUND: To assess the efficacy of equimolar mixture of nitrous oxide/oxygen (EMNO) to prevent pain induced by venous access ports (VAPs) implantation in cancer patients. PATIENTS AND METHODS: In a randomized, double-blind study on an adult population not knowing the effects of EMNO, cancer patients were randomly assigned to breath via a facial mask, EMNO or a placebo mixture comprising 50% oxygen and 50% nitrogen. The primary end-point was the patients' assessment of the severity of pain evaluated using a visual analog scale (VAS, 0 to 100) and the proportion of patients suffering pain in each group. The secondary criteria were side effects, tolerability of EMNO, and the level of satisfaction of both the patients and the medical team. RESULTS: Eighty-three adults (42 in the EMNO group and 41 in the placebo group) were included. VAPs were implanted in the jugular vein in 95% of patients. In the placebo group, 78% of the patients declared that they found VAP implantation painful vs. 34% in the EMNO group (p=0.001). The severity of the pain was reduced by 50% in the EMNO group in comparison with placebo (p=0.0125). Although the median time to perform implantation was strictly identical in both groups (20 min), the estimated duration of surgery seemed longer to patients in the control group. Patient and investigator satisfaction indexes were >90% in both groups. CONCLUSION: EMNO provides an effective solution for the prevention of pain during placement of VAPs.  相似文献   
998.
Editorial     
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999.
While pathophysiology of elevated cytokines is well delineated, reference values for children are unknown, although they may vary physiologically with age and differ from those of adults. Between June and November 2001, interleukin (IL)-6, IL-10 and tumor necrosis factor-alpha (TNF-alpha) concentrations from blood samples of 79 healthy children in six different age groups (group I: 0-3 months; group II: 4-12 months; group III: 13-24 months; group IV: 25-36 months; group V: 37-48 months; group VI: 49-60 months) were measured with ELISA. TNF-alpha was within 2.2-3.5 pg/ml in all groups with a trend toward higher values in groups II and III (p = ns). IL-6 was significantly lower in group III than in groups IV (p = 0.0165) and VI (p = 0.0147). IL-10 was within 3.3-5.5 pg/ml in all groups (p = ns). In regression analysis no correlation between age and cytokine concentrations was found. Although not statistically significant, IL-6 was lower and TNF-alpha higher than the adult reference values provided by the kit manufacturer. Although reference cytokine levels seem not age-related during early infancy, IL-6 is significantly lower during the second year of life than later. In infants aged 5 years or younger, reference levels of IL-6 should be chosen lower, and those of TNF-alpha higher, than the adult reference values.  相似文献   
1000.
In two source memory tests, hallucinating patients with schizophrenia (N=30), compared to non-hallucinating (N=31), are impaired in recognizing internal self-generated items and misattribute them to an external event. They are not impaired in recognizing events from two internal sources. Results support a selective source-monitoring deficit in the occurrence of auditory hallucinations.  相似文献   
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