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OBJECTIVE: To evaluate two nursing approaches to promoting smoking cessation during initial antenatal visits. DESIGN: Experimental, with assignment to interventions using a random, alternate-day strategy and blind assessment of smoking at baseline, 1 month postintervention, 36 weeks' gestation, and 6 weeks postpartum. SETTING/PARTICIPANTS: 224 daily smokers, fewer than 31 weeks gestation, during first prenatal visit, at a teaching hospital antenatal clinic. INTERVENTIONS: An evening class providing guidance on a self-help program for 2 hours on a group basis or 20 minutes on an individual basis during the prenatal appointment. MAIN OUTCOME MEASURE: Smoking cessation, confirmed by urinary cotinine levels. RESULTS: All women assigned to the referral intervention received a referral, but none attended the classes. In contrast, 93% assigned to the immediate intervention received the intervention. The group receiving immediate intervention had two to three times higher rates of cessation at all follow-up periods, with significant differences at the 1-month follow-up. There were certain similarities between the groups. CONCLUSION: Cessation interventions should be administered during the first prenatal visit.  相似文献   
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Six analogs of the highly delta opioid receptor selective, conformationally restricted, cyclic peptide [d -Pen2,d -Pen5]enkephalin, Tyr-d -Pen-Gly-Phe-d -PenOH (DPDPE), were synthesized and evaluated for opioid activity in rat brain receptor binding and mouse vas deferens (MVD) smooth muscle assays. All analogs were single amino acid modifications of DPDPE and employed amino acid substitutions of known effects in linear enkephalin analogs. The effect on binding affinity and MVD potency of each modification within the DPDPE structural framework was consistent with the previous reports on similarly substituted linear analogs. Conformational features of four of the modified DPDPE analogs were examined by 1H NMR spectroscopy and compared with DPDPE. From these studies it was concluded that the observed pharmacological differences with DPDPE displayed by diallyltyrosine1-DPDPE ([DAT1]DPDPE) and phenylglycine4-DPDPE ([Pgl4]DPDPE) are due to structural and/or conformational differences localized near the substituted amino acid. The observed enhanced μ receptor binding affinity of the carboxamide terminal DPDPE-NH2 appears to be founded solely upon electronic differences, the NMR data suggesting indistinguishable conformations. The observation that the α-aminoisobutyric acid substituted analog [Aib3]DPDPE displays similar in vitro opioid behavior as DPDPE while apparently assuming a significantly different solution conformation suggests that further detailed conformational analysis of this analog will aid the elucidation of the key structural and conformational features required for action at the δ opioid receptor.  相似文献   
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The facility-based assessment (FBA) method is a co-ordinatedset of data collection activities, designed to determine theextent to which children are properly diagnosed and effectivelytreated at health facilities. Eleven African countries haveconducted facility-based assessments since 1986, with supportfrom the African Child Survival Initiative-Combatting ChildhoodCommunicable Diseases project. Components of the FBA includeobservations of health worker performance; exit interviews withcaretakers; interviews with health service personnel; reviewsof clinic records; and inventories of available equipment andsupplies. Data resulting from applications of the method canbe used to identify training needs among health personnel, andlogistic problems that limit the quality of service delivery.Repeated surveys can be used to assess the impact of trainingand other interventions designed to improve service quality.  相似文献   
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A pseudopeptide analog of the active core of the leucokinin insect neuropeptide family was synthesized and found to retain myotropic activity. No reports of active pseudopeptide analogs of an insect or other invertebrate neuropeptide have previously appeared in the literature. The pseudopeptide (Pheψ[CH2-NH] Phe-Ser-Trp-Gly-NH2) contains a reduced-amide linkage between the two N-terminal Phe residues. Unlike its amide-bond containing counterpart, the activity of the pseudopeptide was not destroyed upon exposure to aminopeptidase M.  相似文献   
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Endogenous opioid peptides are involved in feeding regulation, and alterations in opioidergic regulation have been implicated in the pathophysiology of eating disorders. To investigate further this hypothesis, we conducted a placebo-controlled study of the effect of the opiate alkaloid morphine on cortisol and prolactin secretion in six patients with anorexia nervosa and six age-matched healthy volunteers, and compared the results with those obtained in nine depressed patients. Basal cortisol but not basal prolactin levels were elevated in patients with anorexia nervosa and patients with depression. Following the administration of morphine plasma concentrations of cortisol levels declined progressively and at a similar rate in all three groups. The prolactin response to morphine was attenuated significantly in patients with depression. Neither the cortisol and prolactin response to morphine in the anorectic patients nor the cortisol response in the depressed patients we observed in this study suggests altered opiate receptor sensitivity. However, the decreased prolactin response to morphine in depressed patients remains compatible with this hypothesis.  相似文献   
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Two peptide segments designated LLP1 (residues 828-855) and LLP2 (residues 768-788) of the HIV-1 transmembrane (TM) envelope protein display structural and functional properties of calmodulin (CaM) binding. These LLP segments may contribute to cytopathogenesis by binding cellular CaM and inhibiting normal CaM-regulated signal transduction pathways. To determine whether these peptides could interrupt signal transduction in vivo, a cellular assay which uses a reporter gene linked to the nuclear factor of activated T cells (NF-AT) was used. Signal transduction perturbation was tested by exogenous addition of LLPs, W-7 or ionomycin; the LLPs inhibited NF-AT-mediated signal transduction as measured by reduced reporter activity. The LLP inhibition profile of NF-AT-driven luciferase activity was similar to the CaM inhibitor W-7. This was in direct contrast to ionomycin, a mobile calcium ion carrier which caused a significant increase in luciferase activity. These findings are consistent with the hypothesis that the CaM-binding properties of TM may contribute to defects in signal transduction leading to the T-cell anergy observed in patients infected with HIV-1.  相似文献   
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