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81.
Effects of the dopamine antagonist veralipride on hot flushes and luteinizing hormone secretion in postmenopausal women 总被引:1,自引:0,他引:1
G B Melis M Gambacciani A Cagnacci A M Paoletti V Mais P Fioretti 《Obstetrics and gynecology》1988,72(5):688-692
The effects on hot flushes of the dopamine antagonist Veralipride versus placebo were investigated in a randomized double-blind study of postmenopausal healthy women (N = 20 in each group). Cutaneous temperature recording and plasma LH pulsatility were studied in eight patients from each group. Veralipride administration (100 mg/day for 30 days) induced a significant (P less than .01) reduction in vasomotor symptoms and was more effective (P less than .05) than placebo. Treatment was followed by the expected increase (P less than .001) in plasma prolactin levels and by a significant decrease (P less than .05) in mean plasma LH. A significant reduction (P less than .01) was observed in objectively recorded hot flushes after Veralipride treatment, whereas there was no significant change in the characteristics of LH pulsatility. Infusion of the opioid antagonist naloxone (N = 5) induced a significant (P less than .01) increase in LH secretion after Veralipride administration. These results suggest that the endogenous opioid system may mediate the endocrine and clinical effects of long-term Veralipride treatment. 相似文献
82.
83.
1014 subjects on the island of Sardinia (Italy) were interviewed regarding the habit of clenching and grinding their teeth. They had to specify if this activity occurred during the day, during the night, or both. Other information recorded was their age, gender, marital status, and occupation. Overall prevalence of bruxism was 27.2% (276 subjects). No association was found between bruxism and age, gender and job. Even differentiating diurnal, nocturnal, diurnal and nocturnal bruxism, associations were non-significant. Marital status seems to make some difference: divorced people reported higher parafunctional activity compared to widows and widowers who reported the least. Although awareness of bruxism is not a precise measure of parafunction, based on the results we cannot support the role of stress on bruxism etiology. 相似文献
84.
85.
The effect of muscimol, a GABAA receptor agonist, injected into the paraventricular nucleus (PVN) of the hypothalamus on drug-induced (apomorphine, oxytocin and NMDA) yawning and penile erection, and on the increase in the concentration of NO2- and NO3- occurring in the paraventricular dialysate in these experimental conditions, was studied in male rats. Muscimol (50, 100 and 200 ng) reduced, in a dose-dependent manner, penile erection and yawning induced by apomorphine (50 ng), oxytocin (30 ng) and NMDA (50 ng) delivered into the PVN. The reduction of penile erection and yawning was parallel to a reduction of the concomitant NO2- and NO3- increase that occurs in the paraventricular dialysate in this experimental condition. In contrast, baclofen (200 ng), a GABAB receptor agonist, was ineffective. The muscimol effects on drug-induced penile erection, yawning and NO2- increase were prevented by the prior administration of bicuculline (250 ng into the paraventricular nucleus). Muscimol (200 ng) but not baclofen (200 ng), injected into the PVN, reduced both noncontact erections in male rats placed in the presence of an inaccessible receptive female, and also the NO2- increase that occurs in the paraventricular dialysate in this experimental condition. As found with drug-induced penile erection, the muscimol reduction of noncontact erections and of NO2- increase was prevented by bicuculline. The present results show that the activation of GABAA receptors in the PVN reduces yawning and penile erection induced by drugs or physiological stimuli by reducing the increase in NO activity that occurs in this hypothalamic nucleus in these experimental conditions. 相似文献
86.
Differential effects of three interferon betas on neutralising antibodies in patients with multiple sclerosis: a follow up study in an independent laboratory
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Bertolotto A Malucchi S Sala A Orefice G Carrieri PB Capobianco M Milano E Melis F Giordana MT 《Journal of neurology, neurosurgery, and psychiatry》2002,73(2):148-153
OBJECTIVE: To evaluate the incidence and the prevalence of neutralising antibodies (NABs) to three interferon beta (IFNbeta) products in patients with multiple sclerosis (MS). METHODS: Sera were tested from 125 patients with relapsing-remitting MS. Patients were treated with IFNbeta-1b (Betaferon, n = 29) 8 MIU subcutaneously every other day, IFNbeta-1a (Avonex, n = 44) 30 microg intramuscularly once weekly, or IFNbeta-1a (Rebif, n = 36) 22 microg subcutaneously three times weekly for 6 to 18 months. An additional 16 patients were treated with Rebif 22 microg intramuscularly once or twice weekly. NABs were assessed using the cytopathic effect assay before treatment and every three months during treatment. Patients with two or more consecutive positive samples were considered to be persistent NAB positive (NAB+). RESULTS: At baseline, no patients were NAB+. NABs developed during the first three months of treatment and continued to develop until month 18. Over 18 months of treatment, the risk of being persistent NAB+ was 31% for Betaferon, 15% for Rebif, and 2% for Avonex (Betaferon versus Avonex, p = 0.001; Betaferon versus Rebif, p = 0.19; Rebif versus Avonex, p = 0.04). In all patients with one or more NAB+ samples, the risk of becoming NAB+ was 38% for Betaferon, 18% for Rebif, and 7% for Avonex (Betaferon versus Avonex, p = 0.0007; Betaferon versus Rebif, p = 0.10; Rebif versus Avonex, p = 0.07). At month 18, the prevalence of persistent NAB+ patients was 31.6% for Betaferon, 18.7% for Rebif, and 4% for Avonex. Numbers of NAB+ patients observed were similar with intramuscular Rebif and with subcutaneous Rebif. CONCLUSION: The three IFNbeta preparations have different degrees of immunogenicity, with Betaferon producing the highest incidence of NABs and Avonex the lowest. These differences should be considered by neurologists when selecting treatment for their patients with MS because NABs can reduce both bioavailability and clinical efficacy of IFNbeta. 相似文献
87.
Melis M Gessa GL Diana M 《Progress in neuro-psychopharmacology & biological psychiatry》2000,24(6):993-1006
1. The mechanism underlying morphine and cannabinoid-induced excitation of meso-accumbens and nigro-striatal dopaminergic neurons was investigated by extracellular single unit recording techniques coupled with antidromic activation from the nucleus accumbens and striatum respectively, in unanesthetized rats. 2. The intravenous administration of cumulative doses (1-4 mg/kg) of morphine, dose-dependently increased the firing rate of dopaminergic neurons projecting to the nucleus accumbens and neostriatum, while the same doses inhibited the activity of pars reticulata neurons of the substantia nigra. Both effects were antagonized by naloxone (0.1 mg/kg i.v.) but not by the selective CB1 receptor antagonist SR 141716A (1 mg/kg i.v.). 3. The intravenous administration of cumulative doses (0.125-0.5 mg/kg) of delta9-tetrahydrocannabinol (delta9-THC) also increased the firing rate of meso-accumbens and nigro-striatal dopaminergic neurons; this effect was antagonized by SR 141716A (1 mg/kg i.v.), but not by naloxone. 4. Furthermore, nor delta9-THC up to a dose of 1 mg/kg, maximally effective in stimulating dopamine neurons, neither SR 141716A (1 mg/kg i.v.) at a dose able to reverse the stimulatory effect of delta9, THC on dopamine cells, did alter the activity of SNr neurons. 5. The results indicate that morphine and delta9-THC activate dopaminergic neurons through distinct receptor-mediated mechanisms; morphine may act by removing the inhibitory input from substantia nigra pars reticulata neurons (an effect mediated by mu-opioid receptors). Alternatively, the delta9-THC-induced excitation of dopaminergic neurons seems to be mediated by CB1 cannabinoid receptors, while neither mu-opioid receptors nor substantia nigra pars reticulata neurons are involved. 相似文献
88.
Stefano Guerriero Silvia Ajossa Valerio Mais Anna Maria Paoletti Gian Benedetto Melis 《Journal of assisted reproduction and genetics》1996,13(5):407-412
Purpose: Our goal was to assess, with a prospective study, the role of hysterosalpingo-contrast sonography (HyCoSy) with an echocontrast agent and transvaginal ultrasonography alone in the evaluation of tubal status.
Methods: Thirty patients were included in the study. These patients underwent an initial plain transvaginal ultrasound examination the day before the HyCoSy. The findings obtained from both examinations were compared with laparoscopic diagnosis, performed in the same menstrual cycle.
Results: The kappa values were 0.48 for patency evaluation and 0.67 for the diagnosis of the presence of at least one patent tube, suggesting a good agreement in both cases between HyCoSy and surgery. HyCoSy had a significantly lower sensitivity (50%), but not a significantly higher specificity (75%), than transvaginal ultrasonography alone in the diagnosis of tubal infertility-related abnormalities such as peritubal adhesions.
Conclusions: The study demonstrates that the HyCoSy is a useful test when scheduling the most suitable treatment for infertile couples. 相似文献
89.
Guerriero Stefano Mais Valerio Ajossa Silvia Paoletti Anna Maria Risalvato Andrea Melis Gian Benedetto 《Journal of assisted reproduction and genetics》1994,11(7):346-352
Purpose
Our purpose was to assess, with a prospective study with random assignment of the day of the first evaluation, whether a single transvaginal ultrasonographic evaluation together with the determination of plasma hCG levels could be used to screen embryonic viability in early asymptomatic pregnancy.Methods
In 260 pregnant women observed from January 1991 to November 1993 with spontaneous pregnancies where the exact date of ovulation was known, a single transvaginal ultrasonographic measurement of gestational sac with determination of plasma hCG levels, transformed to their natural logarithm (lnhCG), was performed. An abnormal result was defined as a value of lnhCG per mean gestational sac below the 95% lower confidence limit of the viable pregnancy group.Results
The sensitivity was 31%, with a specificity of 97%.Conclusion
The study demonstrates that this method has a poor predictive capacity to distinguish viable pregnancy from nonviable pregnancy with a kappa value less than 0.4. 相似文献
90.
Effects of gemcitabine on cell proliferation and apoptosis in non-small-cell lung cancer (NSCLC) cell lines 总被引:4,自引:0,他引:4
Pace E Melis M Siena L Bucchieri F Vignola AM Profita M Gjomarkaj M Bonsignore G 《Cancer chemotherapy and pharmacology》2000,46(6):467-476
We evaluated the antiproliferative and the proapoptotic ability of gemcitabine in three non-small-cell lung cancer (NSCLC)
cell lines. NCI-H292 (mucoepidermoid carcinoma), NCI-CorL23 (large-cell carcinoma) and NCI-Colo699 (adenocarcinoma) cells
were cultured with and without 0.5, 0.05 and 0.005 μM gemcitabine for 24, 48 and 72 h, respectively. Gemcitabine exerted a stronger and earlier antiproliferative and proapoptotic
effect on H292 cells than on CorL23 or Colo699 cells. Fas receptor expression was increased in all three cell lines and was
higher in Colo699 than in CorL23 cells. The incubation of NSCLC with anti-Fas agonistic monoclonal antibody (CH11) induced
cell apoptosis in H292 cells, demonstrating that the Fas receptor was functionally active. Finally, gemcitabine and CH-11
exerted a synergistic effect on cell apoptosis in H292 cells. This study demonstrates that gemcitabine induces apoptosis in
NSCLC and that this effect might be exerted by modulating functionally active Fas expression, and these effects of gemcitabine
were stronger in H292 cells than in either CorL23 or Colo699 cells.
Received: 24 March 1999 / Accepted: 25 July 2000 相似文献