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31.
Roxatidine acetate, a new H2 receptor antagonist, was compared with ranitidine in the treatment of duodenal ulcers in a double-blind multicentre study. Eighty-four patients with endoscopically proven duodenal ulcer were randomized to receive 150 mg roxatidine acetate or 300 mg ranitidine at bedtime. Repeat endoscopy was performed after 4 weeks (25–33 days) and if the ulcer had not healed, another endoscopy was performed after a further 4 weeks of treatment. Using per protocol analysis 73.6% of ulcers treated with roxatidine healed at 4 weeks compared to 72.2% of ulcers treated with ranitidine (P=NS). The healing rates at 8 weeks were 92% with roxatidine and 83.3% with ranitidine (P=NS). Using equivalence tests, the healing rate of roxatidine was found to be equivalent to that of ranitidine within a 20% region. Roxatidine users took significantly less antacids than ranitidine users (P < 0.05). There were no significant adverse effects due to roxatidine or ranitidine. Roxatidine is a safe effective drug in the treatment of duodenal ulcers with a healing rate comparable to that of ranitidine.  相似文献   
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Based on pre-clinical studies suggesting that magnesium (Mg) reduces cocaine self-administration and potentiates the antinociceptive effects of morphine, we conducted a preliminary randomized clinical trial investigating Mg for the treatment of illicit cocaine and opiate use. Eighteen methadone-maintained patients who used illicit opiates and cocaine received either Mg (732 mg/day) or placebo for 12 weeks. Overall, findings showed that the percentage of urine screens testing positive for opiates in the Mg group (22.6%) was half that of the placebo group (46.4%), p = .04; the difference was even greater in the "medication compliant" sample (Mg: 16.3%, placebo: 47.9%), p = .02. Cocaine craving was lower in the Mg compared to the placebo group, but there was no difference between groups in cocaine use. These preliminary findings suggest that Mg may have a beneficial effect for reducing illicit opiate use. It is possible that a higher dose of Mg than was used in this study may be needed to decrease cocaine use.  相似文献   
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RATIONALE: Increasing concomitant abuse of cocaine and morphine-like opioids has prompted a number of studies aimed at understanding how these drugs interact. OBJECTIVE: The present study was designed to determine if variations in opioid pretreatment time would affect how mu opioid agonists interact with cocaine. METHODS: Rats were trained to discriminate 10 mg/kg cocaine from saline. One group of subjects (n=6) received morphine (5.6 mg/kg) 0.5 h, 1 h or 4 h prior to cumulative doses of cocaine (0.1-17.8 mg/kg). These pretreatment times were selected to overlap with states of acute opioid tolerance (approximately 1 h) or acute opioid dependence (approximately 4 h) as demonstrated by previous studies. A second group (n=6) was administered naloxone (0.3 mg/kg) 5 min prior to cumulative cocaine doses, with or without a 4-h morphine (5.6 mg/kg) or methadone (3.0 mg/kg) pretreatment. In a third procedure, the same subjects used in the second experiment were also tested for time-dependent changes in the analgesic effect of morphine using a hot-plate assay. RESULTS: Morphine pretreatment 1 h prior to assessment of the cocaine dose-response function significantly enhanced the discriminative stimulus effects of cocaine. However, neither 0.5-h or 4-h morphine pretreatment had any effect. In contrast, when naloxone was administered 4 h following either morphine or methadone and 5 min prior to assessment of the cocaine dose-response curve, the discriminative stimulus effects of cocaine were significantly attenuated. In assessing morphine-induced analgesia, paw-lick latency was significantly longer at 1 h and shorter at 4 h following morphine administration. CONCLUSIONS: The results illustrate the importance of temporal parameters for interactions between cocaine and mu opioid agonists.  相似文献   
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A group of 99 babies born in hospital and subsequently transferred to the special care unit were examined for the presence of candidas orally. The rate of isolation rose from 6% neonatally to 53% on day 14 of life. Among infants who did not harbour the organisms when discharged from hospital, colonization rapidly took place so that 79% did so at 4 weeks of age, after which the rate fell to 50% at one year of age. The low incidence of clinical candidosis suggests that in these babies as in other groups C. albicans is normally a harmless commensal.  相似文献   
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Rationale: Previous pre-clinical studies with an anti-cocaine monoclonal antibody left open several issues critical to assessing the effectiveness of a vaccine for altering cocaine self-administration behavior. Objectives: The objectives of this study were to determine, first, whether changes in self-administration behavior would be systematically related to antibody level and, second, how the antibody affected the self-administration of different doses of cocaine. Methods: Two experiments were conducted using a second-order schedule of drug delivery in rats. The first was a passive-administration study using the anti-cocaine monoclonal antibody MO240 to examine the relationship between antibody level and cocaine self-administration behavior, and the second was an active-immunization study to examine the efficacy of the cocaine vaccine IPC-1010 for blocking various doses of self-administered cocaine. Results: The passive-administration experiment with control and 4-mg or 12-mg MO240 treatments showed that antagonism of the 1 mg/kg cocaine training dose was dependent on antibody level. In animals whose serum antibody levels were sustained above 0.05 mg/ml, there was a sufficient amount of antibody to reduce drug-seeking behavior and drug intake. In the active-immunization experiment, the cocaine vaccine IPC-1010 induced average serum antibody levels of 0.08 mg/ml and reduced the reacquisition of behavior by 1 mg/kg cocaine. Antagonism of cocaine self-administration after immunization was evident across a range of doses of cocaine and was only apparent in animals whose serum antibody levels exceeded 0.05 mg/ml. Furthermore, there was no evidence that the antagonism was surmountable within the dose range examined (up to 5.6 mg/kg). Conclusions: Antagonism of cocaine self-administration across a range of doses is feasible after immunization with a cocaine vaccine as long as antibody levels are of a sufficient concentration. Received: 2 April 1999 / Final version: 25 September 1999  相似文献   
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Eight cases of dermatomyositis in children admitted to Scottish hospitals between 1962 and 1972 have been reviewed. 6 of the 8 were currently in complete remission. In the other 2 cases the disease remained active in 1 and 1 had died of cardiac failure 6 years after the onset of disease. 5 had developed extensive soft tissue calcification for which 2 were treated with ethanehydroxydiphosphonate, one showing definite improvement and the other no change. All had been treated with corticosteroids and two in addition had had cytotoxic agents (methotrexate or cyclophosphamide). The overal prognosis had probably been improved by the use of corticosteroids but not by the cytotoxic drugs. Only one of the patients was incapacitated by residual contractures or calcinosis.  相似文献   
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