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A review of 174 consecutive patients admitted with a diagnosis of perforated peptic ulcer to eight Hunter Region hospitals during 1979–86 is presented. Among the female admissions, the proportion of patients > 70 years of age was twice that in males. One-third of all perforations were in females who accounted for two-thirds of all perforated gastric ulcers. Multivariate analysis revealed that perforations located in the stomach and older age were both significant independent variables adversely affecting outcome following surgery. In contrast, shock at presentation and delay in operating were not statistically significant independent risk factors.  相似文献   
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The effect of oral premedication was investigated in a double-blind, randomised trial in 85 children undergoing tonsillectomy and/or adenoidectomy. Orally administered midazolam 0.5 mg.kg−1 given 30 min pre-operatively was compared with trimeprazine 2 mg.kg−1 given 90 min pre-operatively and a placebo preparation. Compliance, sedation and ease of induction were assessed as were the duration and quality of recovery. Following premedication with midazolam none of the patients was anxious, crying or distressed on leaving the ward, compared with 2/28 in the trimeprazine group and 5/28 in the placebo group (p =0.0007). More patients were calm and quiet on arrival in the anaesthetic room following midazolam than following trimeprazine, with both premedicant agents comparing favourably with placebo. There was no significant difference between the three groups in the time to recovery or the sedation score on discharge to the ward. Midazolam is a safe and effective oral premedicant for children.  相似文献   
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We surveyed 655 health professionals affiliated with tertiary level neonatal intensive care units in Canada and the United States to define an expanded role for nurses in neonatology and to determine the educational requirements for the role. The role, comprising advanced clinical practice, educational, research, and administrative responsibilities, is a blend of nurse practitioner and clinical nurse specialist activities. Based on survey findings, a neonatal stream within the existing Master of Health Sciences program at McMaster University was developed. To date, 15 clinical nurse specialists/neonatal practitioners (CNS/NPs) are employed in five neonatal intensive care units in Ontario and other related institutions. A randomized trial to evaluate these individuals is in progress.  相似文献   
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BACKGROUND: Acute administration of different classes of antidepressants can enhance or reduce spontaneous locomotor activity in a novel environment, but the effects of chronic antidepressant treatment on spontaneous locomotor activity in novel and familiar environments are less well characterized. Because norepinephrine is an important regulator of spontaneous locomotor activity, we speculated that norepinephrine transporter blockade contributes to the effects of some antidepressants on spontaneous locomotor activity. METHODS: Antidepressant drugs (reboxetine, desipramine, imipramine, venlafaxine, bupropion) were administered acutely (intraperitoneal) or chronically (via osmotic minipump) to control and norepinephrine transporter knockout mice, and spontaneous locomotor activity in novel or familiar environments was recorded. RESULTS: Acute treatment with most norepinephrine transporter-blocking antidepressants decreased spontaneous locomotor activity in a novel environment, whereas chronic treatment decreased spontaneous locomotor activity in both novel and familiar environments. The exception was bupropion, a dual norepinephrine transporter/dopamine transporter blocker, which tended to increase spontaneous locomotor activity. Coadministration of reboxetine and the dopamine transporter blocker GBR 12909 also increased spontaneous locomotor activity. Norepinephrine transporter knockout mice had low basal spontaneous locomotor activity, which was increased by bupropion, whereas reboxetine had no effect in norepinephrine transporter knockout mice. CONCLUSIONS: Acute or chronic inactivation of the norepinephrine transporter decreases spontaneous locomotor activity in novel and familiar environments unless coupled with dopamine transporter blockade.  相似文献   
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The effects of GABA receptor agonists on prolactin secretion in vitro was examined using a rapid superfusion system. GABA and muscimol caused a biphasic effect on prolactin secretion, both components of which were antagonised by bicuculline methiodide, while baclofen had no effect on basal or stimulated secretion, demonstrating the GABAA receptor specificity of both components. Homocarnosine caused only inhibition of secretion, and a range of partly rigid GABA analogues were relatively poor at causing stimulation of secretion. Both effects of muscimol were antagonised by low-chloride medium and the anion channel blocker DIDS, but strychnine and picrotoxinin were both potent and selective antagonists of the stimulatory effect. These results demonstrate a novel biphasic effect of GABAA agonists or prolactin secretion, the two components of which appear to be independent and mediated by different types or states of GABAA receptor/chloride channel complex.  相似文献   
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We have investigated the molecular basis of the marked elevation in erythrocyte adenosine deaminase (ADA) activity in a kindred with hereditary hemolytic anemia. Red cell ADA-specific activity was verified to be 70- to 100-fold normal levels. Western blots demonstrated a corresponding increase in erythrocyte ADA-specific immunoreactive protein. Analysis of genomic DNA revealed no evidence for amplification or major structural changes in the ADA gene. ADA-specific messenger RNA (mRNA) from proband reticulocytes was comparable in size and amount to mRNA from control reticulocytes. Translation of proband poly A+ reticulocyte mRNA in a rabbit reticulocyte lysate system and immunoprecipitation of 35S-labeled protein products with anti-ADA antibody yielded a band of approximately 42,000 apparent mol wt that was absent in translation products from control reticulocyte mRNAs. These data suggest that the increased ADA activity in red cells in this disorder results from the increased translation of an aberrant ADA mRNA.  相似文献   
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