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991.
BACKGROUND: The pathophysiology of persistent gastroesophageal reflux disease (GERD) symptoms after antireflux surgery is unclear. We assessed esophageal sensorimotor function in patients with GERD before and after Nissen fundoplication (NF). METHODS: Sensory and biomechanical properties were evaluated before surgery using impedance planimetry in 17 GERD patients and 16 healthy volunteers. All patients underwent standard laparoscopic NF. Eight GERD patients with persistent symptoms after surgery underwent repeat evaluations at least 12 months after surgery. RESULTS: At baseline, GERD patients had lower thresholds for first perception (P < .001), discomfort (P < .001), and pain (P < .001) compared with controls. The esophagus was more reactive (P = .001) and less distensible (P = .04) in patients than controls. After NF, in patients with persistent symptoms, the sensory thresholds were unchanged (P > .05) but esophageal wall reactivity decreased (P = .001), and distensibility improved (P = .025). CONCLUSIONS: NF improves esophageal biomechanical dysfunction but not the underlying hypersensitivity. Visceral hypersensitivity of the esophagus may explain persistent symptoms after NF.  相似文献   
992.
AIMS: To determine whether a delay of greater than 6h from injury to initial surgical debridement and the timing of antibiotic administration affect infection rates in open long-bone fractures. METHODS: We studied 248 consecutive open long-bone fractures in 237 patients over a 9-year period. The patients were followed until clinical or radiological union occurred or until a secondary procedure for non-union or infection was performed. RESULTS: Surgical debridement was performed within 6h of injury in 62% of cases and after 6h in 38% of cases. Infection rates were 7.8% and 9.6%, respectively, and the difference was not statistically significant (p=0.6438). The timing of antibiotic administration was not significantly related to the infection rate. CONCLUSION: Whilst open long-bone fractures should be treated expeditiously, we suggest that adherence to a 6h window has not been shown to affect infection rates nor has the timing of antibiotic administration during the acute phase.  相似文献   
993.
PurposeComprehensive tobacco control programs have included school-based prevention programs as a key strategy to reach adolescents. Unfortunately, these programs have undergone extensive budget reductions in recent years. In 2003, funding for the Oregon Tobacco Prevention and Education Program was reduced by about 70%, and the school component was entirely defunded. To assess the effects of program funding and subsequent defunding on smoking prevalence within targeted Oregon schools, we compared the change in 30-day smoking prevalence between grades 8 and 11 in school districts in two periods: namely, during funding and after funding was eliminated.MethodsWe used annual school-based survey data for grades 8 and 11 to describe district-level changes in smoking prevalence in five age cohorts: two during the funding period and three after defunding. Each cohort was comprised of districts whose 8th-graders completed the survey and participated again 3 years later. Using mixed models, we compared the change in 30-day adjusted smoking prevalence among cohorts in funded districts, defunded districts, and districts that never received funding.ResultsSmoking prevalence growth was significantly higher among cohorts from the defunded period than for cohorts from the funded period (p = .04) and was not significantly different from schools that were never-funded (p = .79).ConclusionsIn Oregon, funding a school component of a comprehensive tobacco control strategy was associated with depressed uptake of smoking. Gains were quickly lost upon program defunding. School programs are an important strategy if they are long term, comprehensive, and reinforced in the larger environment.  相似文献   
994.
BackgroundEvidence of harms associated with temazepam gel capsule injecting among injecting drug users in Australia led to its withdrawal from manufacture in Australia. Subsequently, diphenhydramine gel capsule injecting was identified among a subset of ethnic Vietnamese injecting drug users.MethodsObservational fieldwork around an active street-based illicit drug marketplace together with targeted purposive sampling enabled 66 ethnic Vietnamese injecting drug users to be recruited for in-depth interview.ResultsData revealed that the injection of gel capsules increases exposure to non-viral infections. Analysis of participant interviews show how participants have established their own ways of reducing these harms including thinning the drug solution by jacking regularly during injection. Controversially, femoral vein administration of diphenhydramine–heroin cocktails was also seen as a harm reduction strategy by participants.DiscussionHealth education campaigns to address the potentially negative consequences of gel capsule groin injection will not be successful unless health workers and policy makers work with drug users and incorporate local understandings and meanings of risk in health promotion activities.  相似文献   
995.
We have previously reported that AMPA-receptor blockade within the rostral ventrolateral medulla (RVLM) attenuates cardiovascular responses and extracellular concentrations of glutamate during mechanical, but not during thermal stimulation [Gray, T., Lewis III, E., Maher, T.J., Ally, A., 2001. AMPA-receptor blockade within the RVLM modulates cardiovascular responses via glutamate during peripheral stimuli. Pharmacol. Res. 43, 47-54]. In this study, we examined the role of NMDA-receptor blockade within the RVLM on cardiovascular responses and release of biogenic monoamines (serotonin [5HT], dopamine [DA], and norepinephrine [NE]) during both mechanical and thermal nociception using anesthetized Sprague-Dawley rats. Both mechanical and thermal stimulation have been shown to activate peripheral Adelta and C-fiber polymodal nociceptors. Noxious mechanical stimuli were induced by applying a pinch to alternate hindpaw for 5s while the noxious thermal stimuli involved immersion of the metatarsus of alternate hindpaw in a water bath at a temperature of 52 degrees C for 5 s. Mechanical stimulation increased mean arterial pressure (MAP), heart rate (HR), extracellular fluid 5HT, and DA concentrations (n=10). However, extracellular levels of NE were decreased within the RVLM. Furthermore, NMDA-receptor blockade with a competitive antagonist, AP-7 (200 nM), within the RVLM attenuated the cardiovascular responses and changes in 5HT and DA, but had no effect on NE levels. The thermal stimulation elicited similar increases in MAP and HR, however, extracellular levels of 5HT or DA did not change. Concentrations of NE were decreased during a thermal stimulation similar to the levels observed following mechanical stimuli. In contrast to mechanical stimuli, bilateral administration of AP-7 (200-1 mM) into the RVLM had no effect on cardiovascular responses, 5HT, DA or NE concentrations during a thermal stimulation. These results show that NMDA receptors within the RVLM most likely play a role in modulating cardiovascular responses by altering 5HT and DA concentrations within the RVLM during mechanical but not thermal nociception. Overall, the present study delineates the NMDA-receptor mediated central integrative mechanisms within the RVLM that coordinate processing of sensory impulses arising from peripheral noxious stimulation.  相似文献   
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