Abstract:
:Ninety-five nonresident girls of a private school volunteered for the study with the teachers' help as well as parental consent. Ages were approximately 8, 9, and 10 years. They were synchronized with diurnal activity from 0730 to 2100 h and nocturnal rest. Fatigue, drowsiness, and attention were self-rated using visual analogue scales; oral temperature was self-measured and a letter cancellation test was performed. Each of these variables was measured at school at 0900, 1100, 1400, and 1600 h on Mondays, Thursdays, Fridays, and Saturdays for two consecutive weeks in 1987 (March 30-April 11) and again in 1989 (March 13-25) when the youngest group had become 10 years old. According to conventional teacher evaluation of learning (learning performance) within each group, three subgroups were formed: top third, middle third, and bottom third. Time series (more than 50,000 data) were analyzed according to several statistical methods, but mainly chronograms with ANOVA. Similar diurnal changes in oral temperature were validated for each group and subgroups. The occurrence of a diurnal change in self-rated variables (fatigue and drowsiness) and score in letter cancellation was age related: no detection in the 8-year-old group (and subgroups) and validation (p less than 0.002) in 9- and 10-year-old groups (and respective subgroups). A good learning performance was associated with a reduced drowsiness in school girls of 9 and 10 years. Age-related, time-of-day differences in drowsiness (when detected) as well as learning performance effect were not associated with observed duration of sleep. Validated changes in self-rated fatigue were close to that of drowsiness. At 0900 h, girls of 9 and 10 years were more tired when belonging to the bottom third than top third subgroup. Whatever the time of day, self-rated attention was greater in the top than in the bottom third for these girls. Differences related to learning performance were validated in each grade. However, best scores were recorded for the bottom third in the 8-year-old group, while best scores were provided by top third subgroups in 10-year-old girls. It seems that in girls around 8 years of age, critical changes can be detected with regard to the (ontogenic?) occurrence of time-of-day differences in a set of psychophysiologic variables as well as influential effects of learning performance on the same variables. Reported finding are compatible with the hypothesis of circadian oscillators working at the level of the cortex of the human brain.
journal_name
Chronobiol Intjournal_title
Chronobiology internationalauthors
Guérin N,Boulenguiez S,Reinberg A,Di Costanzo G,Guran P,Touitou Ydoi
10.3109/07420529109059164subject
Has Abstractpub_date
1991-01-01 00:00:00pages
131-48issue
2eissn
0742-0528issn
1525-6073journal_volume
8pub_type
杂志文章abstract::Dysregulation of the system of nitric oxide (NO)-cyclic 3',5'-guanosine monophosphate (cGMP) might be involved in the development of hypertension in transgenic hypertensive TGR(mREN2)27 (TGR) rats. The present study was performed to determine possible differences in the day-night pattern and the urinary excretion rate...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420529909116860
更新日期:1999-05-01 00:00:00
abstract::The objective of the present study was to evaluate seasonal periodicity in the prevalence of Helicobacter pylori. A prospective study was performed on 1076 consecutive patients who were investigated in our hospital over a 3-year span because of epigastric complaints. Our findings indicate a significant accumulation of...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420529909016947
更新日期:1999-11-01 00:00:00
abstract::Using both previously published findings and entirely new data, we present evidence in support of the argument that the circadian dysfunction of advancing age in the healthy human is primarily one of failing to transduce the circadian signal from the circadian timing system (CTS) to rhythms "downstream" from the pacem...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.1081/cbi-100101051
更新日期:2000-05-01 00:00:00
abstract::Morningness-eveningness (chronotype) indicates the preferred time of intellectual and physical activity. This cross-sectional study had two main aims. The first aim was to explore associations among chronotype, quality of life, and relationship quality. The second aim of this study was to examine whether the similarit...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.1080/07420528.2020.1802289
更新日期:2020-12-01 00:00:00
abstract::The intrinsic circadian clock requires photoentrainment to synchronize the 24-hour solar day. Therefore, light stimulation is an important component of chronobiological research. Currently, the chronobiological research field overwhelmingly uses photopic illuminance that is based on the luminous efficiency function, V...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420528.2014.966269
更新日期:2015-03-01 00:00:00
abstract::Two different medications, one assumed to be a tranquilizer and the other an antifatigue agent, were tested. Both were found to be ineffective and thus were viewed as placebos and named P1 and P2. The effect of P1 and P2 on the circadian rhythms of a set of variables (e.g., sleep/wake, oral temperature and grip streng...
journal_title:Chronobiology international
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.3109/07420529409057230
更新日期:1994-02-01 00:00:00
abstract::Sleep-related problems, such as symptoms of insomnia, daytime sleepiness, shorter sleep duration, or a delayed sleep-wake schedule, are known to be risk factors for depression. In general, depression is more prevalent in women than in men, but sleep-related problems do not necessarily show similar gender predominance....
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420528.2015.1055756
更新日期:2015-01-01 00:00:00
abstract::Fabry disease is a progressive disease characterized by an enzymatic deficiency of acid alpha-galactosidase and glycosphingolipids storage within the lysosomes. The disease has two phenotypes: classic and nonclassic. Excessive daytime sleepiness is a common sign reported by patients and can be caused by a circadian rh...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.1080/07420528.2018.1560308
更新日期:2019-04-01 00:00:00
abstract::The pineal hormone melatonin is potentially useful in the treatment of disorders, especially sleep disorders, associated with circadian rhythm disturbance. We have examined its effects on sleep, mood, and behaviour in a double-blind, placebo-controlled study of a small group of police officers working spans of seven s...
journal_title:Chronobiology international
pub_type: 临床试验,杂志文章
doi:10.3109/07420529309064485
更新日期:1993-10-01 00:00:00
abstract::Most research papers published in Chronobiology International report the findings of investigations conducted on laboratory animals and human beings. The Journal, its editors and the publication committee endorse the compliance of investigators to the principles of the Declaration of Helsinki of the World Medical Asso...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.1081/cbi-120030045
更新日期:2004-01-01 00:00:00
abstract::The increased prevalence of circadian disruptions due to abnormal coupling between internal and external time makes the detection of circadian phase in humans by ambulatory recordings a compelling need. Here, we propose an accurate practical procedure to estimate circadian phase with the least possible burden for the ...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420528.2013.820740
更新日期:2014-02-01 00:00:00
abstract::Eight diurnally active (06:00-23:00 h) subjects were adapted for 2 days to the room conditions where the experiments were performed. Blood sampling for adenosine metabolites and metabolizing enzymes was done hourly during the activity span and every 30 min during sleep. The results showed that adenosine and its catabo...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420529609012650
更新日期:1996-08-01 00:00:00
abstract::Intense artificial light can phase-shift circadian rhythms and improve performance, sleep, and well-being during shiftwork simulations. In real shiftworkers, however, exposure to sunlight and other time cues may decrease the efficacy of light treatment, and occupational and family responsibilities may make it impracti...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420529509064509
更新日期:1995-04-01 00:00:00
abstract::The circadian clock regulates the daily rhythms of several physiological and behavioral processes. Disruptions in clock genes have been associated with obesity and related comorbidities. This study aimed to analyze the association of DNA methylation signatures at circadian rhythm pathway genes with body mass index (BM...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.1080/07420528.2018.1446021
更新日期:2018-07-01 00:00:00
abstract::The aim of this study was to examine the sleep strategies used in breaks between consecutive shifts. For two weeks, 253 shiftworkers collected data regarding the timing of all shifts and sleeps. The final dataset included 395 between-shift breaks that had a standard duration (i.e. ~16 h). If a break included an entire...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420528.2016.1167716
更新日期:2016-01-01 00:00:00
abstract::Corticosterone levels were determined in the 7-week-old male rat maintained under different feeding and lighting schedules. At 4 weeks of age, the animals were kept either under a natural photoperiod (LD) or were subjected to continuous illumination (LL). Access to food was either ad libitum or restricted to an 8 hr s...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420528409063909
更新日期:1984-01-01 00:00:00
abstract::Social anxiety has recently been linked to morningness-eveningness; however, the psychological mechanisms underlying this relationship are not well known. As such, the purpose of the current study is to propose a model by which morningness-eveningness is related to social anxiety symptoms through punishment sensitivit...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.1080/07420528.2018.1529679
更新日期:2019-02-01 00:00:00
abstract::The regulation of genetic expression is tightly controlled and well balanced in the organism by different epigenetic mechanisms such as DNA methylation and histone modifications. DNA methylation occurring after embryogenesis is seen mainly as an irreversible event. Even small changes in genomic DNA methylation might b...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.1080/07420520701290565
更新日期:2007-01-01 00:00:00
abstract::Changes in rectal temperature during mild exercise in the middle of the rising (11:00 h) and falling (23:00 h) phases of the circadian rhythm of resting core temperature have been compared. Seven healthy males were studied at rest, while exercising on a cycle ergometer (60 min at 80 W), and during the first 30 min of ...
journal_title:Chronobiology international
pub_type: 临床试验,杂志文章
doi:10.1080/07420520601142551
更新日期:2007-01-01 00:00:00
abstract::In previous experiments, we found that rats raised in constant light (LL) manifested a more robust circadian rhythm of motor activity in LL and showed longer phase shifts after a light pulse in constant darkness (DD) than chose raised under constant darkness. In addition, we observed that the effects produced by const...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.1081/cbi-100106081
更新日期:2001-07-01 00:00:00
abstract::The suprachiasmatic nucleus (SCN) of the hypothalamus is considered the master circadian oscillator in mammals. However, extra-SCN structures in the brain also display daily rhythms. Recently, we have demonstrated that the choroid plexus (CP) expresses core clock genes that are subjected to circadian regulation in a s...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.1080/07420528.2017.1400978
更新日期:2018-02-01 00:00:00
abstract::The objective of this study was to test the hypothesis that there is seasonal variation in the incidence of Stanford type A aortic dissection (SA-AoD) among patients admitted to our cardiovascular surgical service. A sinusoidal logistic regression model was used to analyze event data for 6081 calendar days. A cyclic p...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420528.2014.933842
更新日期:2014-11-01 00:00:00
abstract::We analyzed the association between change in work schedule and modifications in nutritional status. We performed a panel study with nursing professionals based on two surveys seven year apart (n = 372). Groups with no change in work schedule, change from daytime to night shift, and change from night to daytime shift ...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420528.2016.1167719
更新日期:2016-01-01 00:00:00
abstract::Light is an important environmental stimulus for the entrainment of the circadian clock and for increasing alertness. The intrinsically photosensitive ganglion cells in the retina play an important role in transferring this light information to the circadian system and they are elicited in particular by short-waveleng...
journal_title:Chronobiology international
pub_type: 杂志文章,随机对照试验
doi:10.3109/07420528.2014.893242
更新日期:2014-06-01 00:00:00
abstract::Specific binding of [3H]-imipramine in the rat suprachiasmatic nuclei, occipital cortex and caudate putamen underwent significant and replicable changes throughout 24 hr under a light-dark cycle or under constant conditions. Daily variations were also found in the medial and dorsal raphe nuclei and the lateral hypotha...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420528609066357
更新日期:1986-01-01 00:00:00
abstract::Populations working night shift are high risk for diet-related chronic illness which may result from circadian misalignment. Studies documenting nutritional habits among night shift workers have relied on inaccurate approximations of dietary intake. The primary purpose of this pilot study was to gather feasibility inf...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.1080/07420528.2020.1822857
更新日期:2020-09-28 00:00:00
abstract::Circadian rhythms in mammals are driven by a central clock in the suprachiasmatic nucleus (SCN). In vitro, temperature cycles within the physiological range can act as potent entraining cues for biological clocks. We altered the body temperature (Tc) rhythm in rats by manipulating energy intake (EI) to determine wheth...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420528.2015.1112395
更新日期:2016-01-01 00:00:00
abstract::The pharmacokinetics of naproxen was studied in 12 healthy male volunteers after a single oral dose of 500 mg at 10:00 and 22:00 h. Ingestion of drug at 22:00 h delayed the occurrence of peak serum levels (p < 0.0212). None of the other pharmacokinetic parameters exhibited any significant diurnal variations. ...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.3109/07420529309059703
更新日期:1993-04-01 00:00:00
abstract::Recent studies suggest melatonin, due to its antioxidant and free-radical-scavenging actions, may play a role in the neuroprotection against amyloid, which is implicated in the pathogenesis of Alzheimer's disease (AD). In this study, we determined urinary 6-sulfatoxymelatonin (aMT6s) excretion together with actigraphi...
journal_title:Chronobiology international
pub_type: 杂志文章
doi:10.1081/cbi-100103973
更新日期:2001-05-01 00:00:00
abstract::In 24h studies of bone marrow (BM), circadian stage-dependent variations were demonstrated in the proliferative activity of BM cells from subsets of 35 healthy diurnally active men. On an average, the percentage of total BM cells in deoxyribonucleic acid (DNA) synthesis phase was 188% greater at midday than at midnigh...
journal_title:Chronobiology international
pub_type: 杂志文章,评审
doi:10.1081/cbi-120002594
更新日期:2002-01-01 00:00:00