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Entertainment-education is an effective health communication strategy that combines or embeds educational messages into entertainment programs to bring about social and behavior change. For years, scholars have considered how entertainment-education works. Some contemporary theories posit that entertainment-education does not engender behavior change directly but does so through mediating variables. This study adds to the literature on this topic by exploring the direct relationship between exposure and social norms instead of their relationship through behavior as a mediator. Novel to this study is the use of encoded exposure, a continuous and recognition-based measure of exposure that includes ever watching, recall, involvement, and dose in its operationalization. Using cross-sectional data from Kyunki … Jeena Issi Ka Naam Hai, an entertainment-education program in India, this exploratory analysis indicates a positive and significant relationship between encoded exposure and social norms. How can this finding be applied to future programs? Questions remain, and replication is needed, but if it is not essential to go through behavior in order to change social norms, then implications emerge for the theory and practice of entertainment-education.  相似文献   
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Small-molecule antimicrobial peptidomimetic amphiphiles represent a promising class of novel antimicrobials with the potential for widespread therapeutic application. To investigate the role of spatial positioning for key hydrophobic and hydrophilic groups on the antimicrobial efficacy and selectivity, positional isomers of the lead biphenyl antimicrobial peptidomimetic compound 1 were synthesized and subjected to microbial growth inhibition and mammalian toxicity assays. Positional isomer 4 exhibited 4–8× increased efficacy against the pathogenic Gram-negative bacteria Pseudomonas aeruginosa and Escherichia coli (MIC = 2 μg/mL), while isomers 2, 3, and 7 exhibited a 4× increase in activity against Acinetobacter baumannii (MIC = 4 μg/mL). Changes in molecular shape had a significant impact on Gram-negative antibacterial efficacy and the resultant spectrum of activity, whereas all structural isomers exhibited significant efficacy (MIC = 0.25–8 μg/mL) against Gram-positive bacterial pathogens (e.g., methicillin-resistant Staphylococcus aureus, Streptococcus pneumoniae, and Enterococcus faecalis).  相似文献   
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OBJECTIVES: Studies of the relative frequency of transient lower esophageal sphincter relaxations (TLESRs) in patients with gastroesophageal reflux disease and asymptomatic controls have revealed conflicting data. We have therefore studied the frequency of TLESRs and the frequency and mechanisms of acid reflux episodes in patients with gastroesophageal reflux disease and age- and sex-matched asymptomatic controls using standardized criteria. METHODS: Ten patients with symptomatic gastroesophageal reflux disease (four male, aged 50 [30-59] yr) and 10 asymptomatic matched volunteers (four male, aged 50 [32-59] yr) were studied. Esophageal, lower esophageal sphincter, and gastric manometric and esophageal pH readings were recorded for 1 h before and 1 h after a 200-kcal, 150 ml long-chain triglyceride meal. RESULTS: TLESR frequency increased after the meal in both volunteers (median 0 [range = 0-3] to 3 [0-8] per hour,p < 0.01) and patients (1 [0-6] to 2.5 [0-9] per hour, p = 0.08). There was no significant difference in the frequency of TLESRs between volunteers and patients. TLESRs were more likely to be associated with acid reflux in patients (65% vs 37%, p = 0.03), whereas volunteers were more likely to reflux gas or liquid without acid (30% vs 3.0%, p = 0.01). CONCLUSIONS: TLESRs are no more frequent in patients with gastroesophageal reflux disease than age- and sex-matched asymptomatic volunteers. However, when TLESRs occur in patients, they are twice as likely to be associated with acid reflux.  相似文献   
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Genetic influences in gastro-oesophageal reflux disease: a twin study   总被引:11,自引:0,他引:11       下载免费PDF全文
Mohammed I  Cherkas LF  Riley SA  Spector TD  Trudgill NJ 《Gut》2003,52(8):1085-1089
BACKGROUND: A number of families have been described which include multiple members with symptomatic, endoscopic, or complicated gastro-oesophageal reflux disease (GORD). First degree relatives of patients with GORD are more likely to suffer with GORD symptoms. These observations raise the possibility of a genetic contribution to the aetiology of GORD. AIMS: To determine the relative contribution of genetic factors to GORD by evaluating GORD symptoms in monozygotic (MZ) and dizygotic (DZ) twins. METHODS: A total of 4480 unselected twin pairs, identified from a national volunteer twin register, were asked to complete a validated symptom questionnaire. GORD was defined as symptoms of heartburn or acid regurgitation at least weekly during the past year. RESULTS: Replies were obtained from 5032 subjects (56% response rate). A total of 1960 twin pairs were evaluable: 928 MZ pairs (86 male pairs, mean (SD) age 52 (13) (range 19-81) years) and 1032 DZ pairs (71 male pairs, mean age 52 (13) (20-82) years). The prevalence of GORD among both groups of twins was 18%. Casewise concordance rates were significantly higher for MZ than DZ twins (42% v 26%; p<0.001). Multifactorial liability threshold modelling suggests that additive genetic effects combined with unique environmental factors provide the best model for GORD. Heritability estimates suggest that 43% (95% confidence interval 32-55%) of the variance in liability to GORD is due to additive genetic factors. CONCLUSIONS: There is a substantial genetic contribution to the aetiology of GORD.  相似文献   
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BACKGROUND: Alcohol exposure during development can produce severe and long-lasting central nervous system damage and consequent behavioral alterations. Recent evidence suggests that NMDA receptor-mediated excitotoxicity during periods of withdrawal may contribute to this damage. We have demonstrated that blocking the NMDA receptor with MK-801 during alcohol withdrawal can attenuate ethanol's adverse effects on behavioral development in the rat. This study examined the dose dependency of MK-801's ability to mitigate ethanol's teratogenic effects. METHODS: Neonatal rat pups were exposed to 6.0 g/kg of ethanol in a binge-like manner on postnatal day (PD) 6, a period of brain development equivalent to a portion of the human third trimester. Alcohol administration was accomplished with an artificial rearing procedure. Twenty-one hours after ethanol treatment, pups were injected intraperitoneally with one of four doses of MK-801 (0.05, 0.1, 0.5, or 1.0 mg/kg) or saline vehicle. An artificially reared control and a normally reared control group were included. On PD 18-19, activity level was monitored, and on PD 40-42, serial spatial discrimination reversal learning was assessed. RESULTS: Alcohol exposure on PD 6 produced significant increases in activity level and deficits in reversal learning. These alcohol-induced behavioral alterations were significantly attenuated in subjects treated with one of the three lower doses (0.05-0.5 mg/kg) of MK-801 during withdrawal. The performance of ethanol-exposed subjects treated with the high dose of MK-801 (1.0 mg/kg) did not differ from that of the Ethanol Only group. CONCLUSIONS: These data suggest that alterations in NMDA receptor activation during alcohol withdrawal contribute to the neuropathology and consequent behavioral alterations associated with developmental alcohol exposure. These data have important implications for pregnant women and newborns undergoing ethanol withdrawal.  相似文献   
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