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目的 了解上海市居民膳食营养状况及季节特征。方法 分别在2012-2014年间4个不同季节对上海市代表性样本人群进行追踪调查,采用连续3 d 24 h膳食回顾询问法辅以家庭调味品称重法收集食物摄入信息。依据中国食物成分表计算能量及产能营养素摄入。结果 2012-2014年上海市居民全年平均每标准人日粮谷类摄入量191.09 g、蔬菜250.69 g、水果107.23 g、动物性食物223.53 g、乳及乳制品96.39 g、大豆及其制品11.19 g、烹调油36.54 g、烹调盐7.57 g,不同季节食物消费差异有统计学意义(P<0.05)。平均每标准人日能量摄入量2 048.70 kcal、碳水化合物241.04 g、蛋白质82.35 g、脂肪85.99 g,脂肪提供能量百分比37.99%。季节、年龄、地区和收入是膳食结构的影响因素(P<0.05)。结论 上海市居民能量摄入满足需求,脂肪能量摄入比例较高,膳食结构欠合理。烹调油、盐摄入量低于国家大城市平均水平但仍高于推荐量,应继续开展针对性营养干预。膳食摄入存在季节特征,夏季膳食摄入更合理,相关研究需考虑季节因素影响。 相似文献
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《Sleep medicine》2014,15(7):798-807
ObjectiveDaylight is an important zeitgeber for entraining the circadian rhythm to a 24 h clock cycle, especially within the Polar circle, which has long Polar nights several months each year. Phase delays in sleep timing may occur, but the mean shift is normally small. However, the individual variation in phase shifts is large, implicating moderating factors. Here we examined the role of several self-regulatory variables (mood and fatigue, behavioral habits, and psychological self-regulation) as moderators of seasonality in sleep timing and chronotype.MethodsA sample of 162 young adults (76% females; mean age: females 23.4 years, males 24.3 years) participated in a prospective study across three seasons (September, December, March) in Tromsø/Norway at 69°39′N. Sleep diary and sleep/health-related questionnaire data were collected at each time-point.ResultsSleep timing and chronotype were delayed during the dark period (December) compared with brighter photoperiods (September and March). Comparable effects were observed for insomnia, fatigue, mood (depression and anxiety), subjective health complaints, physical activity, and school-related stress. Most importantly, depression and fatigue moderated the degree of seasonal shifting in sleep timing, whereas the other self-regulation indicators did not (ie eating habits, physical activity, and psychological self-regulation).ConclusionSeasonality in sleep timing and chronotype was confirmed, and it seems that depressive symptoms during the dark period exacerbate phase-shifting problems for people living in sub-Arctic regions. 相似文献
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Vaseekaran Sivarajasingam Nicholas Page Peter Morgan Kent Matthews Simon Moore Jonathan Shepherd 《Injury》2014
Purpose
Injury records from Emergency Departments (EDs) have been studied over the last decade as part of the work of the National Violence Surveillance Network (NVSN) and provide information about local, regional and national violence levels and trends in England and Wales. The purpose of the current study is to evaluate overall, gender, age-specific and regional trends in community violence in England and Wales from an ED perspective from January 2005 to December 2009.Methods
Violence-related injury data were collected prospectively in a stratified sample of 77 EDs (Types 1, 3 and 4) in the nine Government Office Regions in England and in Wales. All 77 EDs were recruited on the basis that they had implemented and continued to comply with the provisions of the 1998 Data Protection Act and Caldicott guidance. Attendance date, age and gender of patients who reported injury in violence were identified using assault-related attendance codes, specified at the local level. Time series statistical methods were used to detect both regional and national trends.Results
In total 221,673 (163,384 males: 74%) violence-related attendances were identified. Overall estimated annual injury rate was 6.5 per 1000 resident population (males 9.8 and females 3.4 per 1000). Violence affecting males and females decreased significantly in England and Wales over the 5-year period, with an overall estimated annual decrease of 3% (95% CI: 1.8–4.1%, p < 0.05). Attendances decreased significantly for both genders across four out of the five age groups studied. Attendances were found to be highest during the months of May and July and lowest in February. Substantial differences in violence-related ED attendances were identified at the regional level.Conclusions
From this ED perspective overall violence in England and Wales decreased over the period 2005–2009 but increased in East Midlands, London and South West regions. Since 2006, overall trends according to Crime Survey for England and Wales (CSEW), police and ED measures were similar, though CSEW and ED measures reflect far greater numbers of violent incidents than police data. Causes of decreases in violence in regions need to be identified and shared with regions where violence increased. 相似文献5.
This paper reviews current knowledge of photoperiod control of GnRH-1 secretion and proposes a model in which two processes act together to regulate GnRH1 secretion. Photo-induction controls GnRH1 secretion and is directly related to prevailing photoperiod. Photo-inhibition, a longer term process, acts through GnRH1 synthesis. It progresses each day during daylight hours, but reverses during darkness. Thus, photo-inhibition gradually increases when photoperiods exceed 12 h, and reverses under shorter photoperiods. GnRH1 secretion on any particular day is the net result of these two processes acting in tandem. The only difference between species is their sensitivity to photo-inhibition. This can potentially explain differences in timing and duration of breeding seasons between species, why some species become absolutely photorefractory and others relatively photorefractory, why breeding seasons end at the same time at different latitudes within species, and why experimental protocols sometimes produce results that appear counter to what happens naturally. 相似文献
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Antonio Preti Davide Sisti Marco B. Rocchi Monica Busca Marcello Vellante Maria Valeria Camboni 《Laterality》2013,18(6):737-752
Males were consistently found to be more likely than females to report left-hand preference in single-hand tasks, but the literature reports negative results too. Using data from a large sample in Sardinia, we aimed at testing the links of left-handedness with sex, age, residence, and seasonality of birth. A total of 4239 participants (males = 1589; females = 2650) were recruited in public places such as high schools, university classes, or gyms in one of the major islands of Italy. Hand preference was established with the question: Which hand do you normally use to write legibly? The monthly distribution of births was studied with the Rayleigh test. In the sample, 270 female participants reported left-hand preference in writing (10.2%) versus 161 male participants (10.1%). Left-hand preference in writing was negatively related to age, with increasing left-hand preference in the younger generations. Left-hand preference in writing was not more common in urban than in suburban or rural settings. The month of birth was found to have a seasonal effect on the left-handed (p=.031) but not on the right-handed (p=.80) participants, and this seasonal effect was more evident in males (p=.04) than in females (p =.26). In our sample males were not more likely to report left-hand preference in writing than females. On the other hand, left-hand preference does vary by age and, in all likelihood, this is an effect of the reduced cultural pressure to write with the right hand in the younger generations. 相似文献
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《Vaccine》2017,35(36):4738-4744
IntroductionWhile vaccination may be relatively straightforward for regions with a well-defined winter season, the situation is quite different for tropical regions. Influenza activity in tropical regions might be out of phase with the dynamics predicted for their hemispheric group thereby impacting the effectiveness of the immunization campaign.ObjectiveTo investigate how the climatic diversity of Mexico hinders its existing influenza immunization strategy and to suggest that the hemispheric vaccine recommendations be tailored to the regional level in order to optimize vaccine effectiveness.MethodsWe studied the seasonality of influenza throughout Mexico by modeling virological and mortality data. De-trended time series of each Mexican state were analyzed by Fourier decomposition to describe the amplitude and timing of annual influenza epidemic cycles and to compare with each the timing of the WHO's Northern and Southern Hemispheric vaccination schedule.FindingsThe timings of the primary (major) peaks of both virological and mortality data for most Mexican states are well aligned with the Northern Hemisphere winter (December–February) and vaccine schedule. However, influenza peaks in September in the three states of the Yucatan Peninsula. Influenza-related mortality also peaks in September in Quintana Roo and Yucatan whereas it peaks in May in Campeche. As the current timing of vaccination in Mexico is between October and November, more than half of the annual influenza cases have already occurred in the Yucatan Peninsula states by the time the Northern Hemispheric vaccine is delivered and administered.ConclusionThe current Northern Hemispheric influenza calendar adopted for Mexico is not optimal for the Yucatan Peninsula states thereby likely reducing the effectiveness of the immunization of the population. We recommend that Mexico tailor its immunization strategy to better reflect its climatologic and epidemiological diversity and adopt the WHO Southern Hemisphere influenza vaccine and schedule for the Yucatan Peninsula. 相似文献
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《Clinical cardiology》2017,40(11):1152-1155