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Background: Existing studies of the association between age at first drink (AFD) and the risk of alcohol use disorders (AUD) suffer from inconsistent levels of control and designs that may inflate associations by failure to control for duration of exposure to risk. Methods: This study examined associations between AFD (ages <15 and 15–17 vs. 18+ years) and first incidence of DSM‐IV alcohol dependence, abuse, and specific AUD criteria over a 3‐year follow‐up in a longitudinal study of U.S. drinkers 18 years of age and older at baseline (n = 22,316), controlling for duration of exposure, family history, and a wide range of baseline and childhood risk factors. Results: After adjusting for all risk factors, the incidence of dependence was increased for AFD < 15 years (OR = 1.38) and for women only with AFD at ages 15 to 17 (OR = 1.54). The incidence of abuse was increased at AFD <15 and 15 to 17 years (OR = 1.52 and 1.30, respectively). Most dependence criteria showed significant associations with AFD, but hazardous drinking and continued drinking despite interpersonal problems were the only abuse criteria to do so. All associations were nonsignificant after controlling for volume of consumption, except that AFD at all ages <18 combined was associated with a reduced likelihood of impaired control, and AFD at ages 15 to 17 was associated with lower odds of drinking more/longer than intended among heavy‐volume drinkers. In a population of low‐risk drinkers that excluded those with positive family histories, personality disorders, and childhood risk factors, there were strong associations between early AFD (<18) and the incidence of dependence (OR = 3.79) and continued drinking despite physical/psychological problems (OR = 2.71), but no association with incidence of abuse. Conclusions: There is a robust association between AFD and the risk of AUD that appears to reflect willful rather than uncontrolled heavy drinking, consistent with misuse governed by poor decision‐making and/or reward‐processing skills associated with impaired executive cognitive function (ECF). Additional research is needed to determine causality in the role of impaired ECF, including longitudinal studies with samples of low‐risk adolescents.  相似文献   
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ObjectiveTo evaluate responses by people with knee osteoarthritis to a brief educational video about their condition that aimed to empower and motivate effective self-management. The video content addressed psychosocial contributors to pain and barriers to behaviour change.MethodsA mixed methods design, including a survey and semi-structured interviews, was used to collect data from 118 people (46–83 years, 78% female) with knee osteoarthritis.ResultsQuantitative data analysis showed the video was rated positively on 0–6 scales for enjoyability (mean 5.0), helpfulness (4.9), relevance (5.0) and believability (5.4). The majority would recommend the video (89%), learned new information (78%) and/or reported intentions to change behaviour (78%). A minority disliked aspects of the video (23%). The thematic analyses identified three main themes: Reactions to the video, including emotions; Learning from the video, including new knowledge and empowerment, but also unmet information needs or disagreement; and Intentions, including behaviour changes, cognitive changes and help seeking.ConclusionEducation about knee osteoarthritis with a focus on empowerment is well received by people with the condition, although some discordant views emerged.Practice implicationsThe educational video about knee osteoarthritis can be recommended to promote effective self-management and counteract potential drawbacks associated with biomedical-based education.  相似文献   
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BackgroundMilk is one of the most common food allergies in US children, yet little is known about its distribution and diagnosis.ObjectiveTo better understand current pediatric milk allergy distribution and diagnosis trends in the United States.MethodsA randomized, cross-sectional survey was administered to parents belonging to a representative sample of US households with children from June 2009 to February 2010. Data from 38,480 parents regarding demographic characteristics, allergic symptoms associated with food ingestion, and methods used to diagnose food allergy were collected and analyzed as weighted proportions. Adjusted models were estimated to examine association of these aspects with odds of milk allergy.ResultsOf the 3,218 children identified with food allergy, 657 (19.9%) were reported to have milk allergy. Asian (odds ratio [OR], 0.5) and black (OR, 0.4) children were half as likely as white children to develop milk allergy. The highest percentage of milk-allergic children (23.8%) were aged 6 to 10 years, and the lowest percentage of milk-allergic children (15.0%) were aged 11 to 15 years. Nearly one-third (31.4%) of children with milk allergy had a history of severe reactions. Compared with children with other food allergies, children with milk allergy had a higher odds of having physician-diagnosed allergy (OR, 1.7) and were twice as likely (OR, 2.1) to outgrow their milk allergy.ConclusionChildhood milk allergy, which accounts for one-fifth of US food allergies, is less prevalent among Asian and black children than white children. Although less than half of children with milk allergy received confirmatory testing, it is the most commonly diagnosed food allergy.  相似文献   
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MRSI permits the non‐invasive mapping of brain temperature in vivo, but information regarding its reliability is lacking. We obtained MRSI data from 31 healthy male volunteers [age range, 22–40 years; mean ± standard deviation (SD), 30.5 ± 5.0 years]. Eleven subjects (age range, 23–40 years; mean ± SD, 30.5 ± 5.2 years) were invited to receive four point‐resolved spectroscopy MRSI scans on each of 3 days in both 1.5‐T (TR/TE = 1000/144 ms) and 3‐T (TR/TE = 1700/144 ms) clinical scanners; a further 20 subjects (age range, 22–40 years; mean ± SD, 30.5 ± 4.9 years) were scanned on a single occasion at 3 T. Data were fitted in the time domain to determine the water–N‐acetylaspartate chemical shift difference, from which the temperature was estimated. Temperature data were analysed using a linear mixed effects model to determine variance components and systematic temperature changes during the scanning sessions. To characterise the effects of instrumental drift on apparent MRSI brain temperature, a temperature‐controlled phantom was constructed and scanned on multiple occasions. Components of apparent in vivo temperature variability at 1.5 T/3 T caused by inter‐subject (0.18/0.17 °C), inter‐session (0.18/0.15 °C) and within‐session (0.36/0.14 °C) effects, as well as voxel‐to‐voxel variation (0.59/0.54 °C), were determined. There was a brain cooling effect during in vivo MRSI of 0.10 °C [95% confidence interval (CI): –0.110, –0.094 °C; p < 0.001] and 0.051 °C (95% CI: –0.054, –0.048 °C; p < 0.001) per scan at 1.5 T and 3 T, respectively, whereas phantom measurements revealed minimal drift in apparent MRSI temperature relative to fibre‐optic temperature measurements. The mean brain temperature at 3 T was weakly associated with aural (R = 0.55, p = 0.002) and oral (R = 0.62, p < 0.001) measurements of head temperature. In conclusion, the variability associated with MRSI brain temperature mapping was quantified. Repeatability was somewhat higher at 3 T than at 1.5 T, although subtle spatial and temporal variations in apparent temperature were demonstrated at both field strengths. Such data should assist in the efficient design of future clinical studies. © 2013 The Authors. NMR in Biomedicine published by John Wiley & Sons, Ltd.  相似文献   
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We recently reported a deletion of exon 2 of the trimethyllysine hydroxylase epsilon (TMLHE) gene in a proband with autism. TMLHE maps to the X chromosome and encodes the first enzyme in carnitine biosynthesis, 6-N-trimethyllysine dioxygenase. Deletion of exon 2 of TMLHE causes enzyme deficiency, resulting in increased substrate concentration (6-N-trimethyllysine) and decreased product levels (3-hydroxy-6-N-trimethyllysine and γ-butyrobetaine) in plasma and urine. TMLHE deficiency is common in control males (24 in 8,787 or 1 in 366) and was not significantly increased in frequency in probands from simplex autism families (9 in 2,904 or 1 in 323). However, it was 2.82-fold more frequent in probands from male-male multiplex autism families compared with controls (7 in 909 or 1 in 130; P = 0.023). Additionally, six of seven autistic male siblings of probands in male-male multiplex families had the deletion, suggesting that TMLHE deficiency is a risk factor for autism (metaanalysis Z-score = 2.90 and P = 0.0037), although with low penetrance (2-4%). These data suggest that dysregulation of carnitine metabolism may be important in nondysmorphic autism; that abnormalities of carnitine intake, loss, transport, or synthesis may be important in a larger fraction of nondysmorphic autism cases; and that the carnitine pathway may provide a novel target for therapy or prevention of autism.  相似文献   
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