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We compared sedation levels in children following administration of intranasal dexmedetomidine. One hundred and sixteen children aged between 1 and 8 years were enrolled in this prospective, randomised trial. Children were assigned to receive either intranasal dexmedetomidine 1 μg.kg?1 (Group 1) or 2 μg.kg?1 (Group 2). Thirty‐one (53%) patients from Group 1 and 38 (66%) patients from Group 2 were satisfactorily sedated at the time of anaesthetic induction. Logistic regression showed a significant interaction effect (p = 0.049), with the odds ratio between Group 2 over Group 1 estimated as 1.1 (95% CI 0.5–2.7) for the 1–4 year age group, and 10.5 (95% CI 1.4–80.2) for the 5–8 year age group. Both doses produced a similar level of satisfactory sedation in children aged 1–4 years, whereas 2 μg.kg?1 resulted in a higher proportion of satisfactory sedation in children aged 5–8 years. There were no adverse haemodynamic effects. We conclude that intranasal dexmedetomidine in a premedication dose of 2 μg.kg?1 resulted in excellent sedation in children.  相似文献   
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BackgroundElimination of catheter-related bloodstream infections is a major focus in health care. According to the Centers for Disease Control and Prevention and the Infusion Nurses Society, the optimal time for needleless connector disinfection has not yet been empirically established.MethodsUsing experimental design and established lab procedure, a 0.5 MacFarland suspension was used to inoculate 172 needleless connectors with bacteria (Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa) and allowed to dry for 18 hours. Five groups of connectors (n = 27 per group) were disinfected using 70% isopropyl alcohol with friction for 5, 8, 10, 12, and 15 seconds, and flushed with 0.5 mL nonbacteriostatic sterile normal saline onto sheep-blood agar plates for incubation at 35°C for 48 hours. Bacterial growth (1 colony) was noted on 2 negative controls; therefore, a second sample (n = 172) was tested as above using additional precautions of masking, gloving, and gowning. A third group of connectors was tested using a 0.5 MacFarland suspension containing yeast (Candida albicans).ResultsGroup 1 showed significant (χ24 = 37.93; P = .00) and strong (Cramér's V = 0.53; P = .00) associations between scrub time and growth status. Although not statistically significant, Groups 2 and 3 demonstrated clinically significant associations between these factors.ConclusionsAlthough additional research is warranted, our study showed that disinfection times of 5 and 8 seconds were inadequate for reducing bacterial transfer. However, disinfection times of 10, 12, and 15 seconds resulted in comparable, decreased rates of bacterial migration.  相似文献   
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Glucagon-like peptide-1 (GLP-1) is a potent insulinotropic hormone proposed to play a role in both the pathophysiology and treatment of type 2 diabetes. This study has employed the GLP-1 receptor antagonist, exendin-4(9-39)amide (Ex(9-39)) to evaluate the role of endogenous GLP-1 in genetic obesity-related diabetes and related metabolic abnormalities using ob/ob and normal mice. Acute in vivo antagonistic potency of Ex(9-39) was confirmed in ob/ob mice by blockade of the insulin-releasing and anti-hyperglycaemic actions of intraperitoneal GLP-1. In longer term studies, ob/ob mice were given once daily injections of Ex(9-39) or vehicle for 11 days. Feeding activity, body weight, and both basal and glucose-stimulated insulin secretion were not significantly affected by chronic Ex(9-39) treatment. However, significantly elevated basal glucose concentrations and impaired glucose tolerance were evident at 11 days. These disturbances in glucose homeostasis were independent of changes of insulin sensitivity and reversed by discontinuation of the Ex(9-39) for 9 days. Similar treatment of normal mice did not affect any of the parameters measured. These findings illustrate the physiological extrapancreatic glucose-lowering actions of GLP-1 in ob/ob mice and suggest that the endogenous hormone plays a minor role in the metabolic abnormalities associated with obesity-related diabetes.  相似文献   
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OBJECTIVES: To estimate the frequency of HIV/sexually transmitted disease (STD) counseling among patients tested for HIV or STD infection at physician offices and hospital outpatient departments and to describe the factors associated with HIV/STD counseling in private settings in the USA. DESIGN: Cross-sectional study of patients served by physicians in private settings in the USA. METHODS: We analyzed 1997-1998 data from two representative national surveys of ambulatory care visits in private settings by persons aged 18-64 years. RESULTS: During 1997-1998, 12.7 million ambulatory care visits included HIV or STD testing. HIV/STD counseling was documented in 35% of all visits and in 28% of visits by pregnant women at the time HIV or STD tests were done. Counseling was less common when only HIV tests (21%) or STD tests (37%) alone were carried out than when both HIV and STD tests (50%) were performed. Counseling was more common (65%) if the patient's reason for visit was related to HIV, STD, or genitourinary complaints than if the visit was for other reasons. CONCLUSIONS: Private physicians often counseled about HIV/STD when testing patients with symptoms. The proportion of other visits in which counseling accompanied HIV or STD tests was variable. This suggests the need for a better understanding of the reasons why clinicians in private settings decide whether to counsel patients about HIV and STD when they order testing, barriers to offering counseling, and interventions to increase counseling when appropriate.  相似文献   
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