| visual and brain function measurements in studies of n-3 fatty acid requirements of infants. | dietary n-6 or n-3 fatty acid deficiencies result in changes in brain and retinal phospholipid composition that can affect cell membrane and organ function. an n-3 fatty acid deficiency has been associated with altered electroretinograms and reduced visual acuity in animals. other promising methods for assessing the effects of fatty acid deficiencies on brain and retinal maturation include visual-evoked potential acuity, sleep-wake cycle, auditory brain stem-evoked response, somatosensory-evoked ... | 1992 | 1560326 |
| nocturnal elevation of plasma melatonin and urinary 5-hydroxyindoleacetic acid in young men: attempts at modification by brief changes in environmental lighting and sleep and by autonomic drugs. | in order to determine whether the human pattern of circulating melatonin resembles that previously described in lower animals, men 19-32 years old were exposed to a light-dark cycle with 14 hours of light per day (l:d 14:10). in whites and blacks, nocturnal (dark phase, sleeping) melatonin levels were almost always elevated to 0.05-0.1 ng/ml plasma compared with lower or undetectable levels during the day, measured by the tadpole bioassay. thin-layer migration of bioactive material was identical ... | 1976 | 1262447 |
| post-natal development of sleep organization in man: speculations on the emergence of the 's process'. | we outline the development during the first year of life of both sleep-wake patterns and internal sleep organization (sleep states, quiet sleep-paradoxical sleep cycles, and slow-wave sleep), and raise the issue of the emergence of the 's process'. the consolidation of sleep in episodes of longer duration takes place during the night; the ability to maintain sleep after sleep onset decreases during the day in infants older than 6 months. the main contribution to the increase of longest nocturnal ... | 1992 | 1630412 |
| a combined behavioral/pharmacological treatment of sleep-wake schedule disorder in angelman syndrome. | angelman syndrome (as) is a genetic disorder associated with a deletion on chromosome 15. behavior problems among children with as include sleep difficulties. data are presented on the successful treatment of a sleep-wake schedule disorder (swsd) in a 9-year-old boy with as. the treatment program included behavioral and pharmacological components. during baseline, the child slept a mean of 1.9 hours per night and 1.3 hours during the day; night sleep was increased to a mean of 8.3 hours and day ... | 1992 | 1506469 |
| sleep propensity free-runs with the temperature, melatonin and cortisol rhythms in a totally blind person. | in previous studies, we found that many totally blind people have free-running melatonin rhythms, but that free-running melatonin rhythms were not necessarily associated with periodic insomnia and daytime sleepiness. thus, it was not clear if the circadian sleep propensity rhythm was free-running with the other circadian rhythms. in the present study, we report that the sleep propensity rhythm (as defined by an ultrashort sleep-wake schedule) free-ran with the melatonin, temperature and cortisol ... | 1992 | 1519008 |
| sleep-wake disorganization in cats exposed to ozone. | the effects of the exposure to ozone in the central nervous system are unknown, as it is doubtful if ozone enters beyond the respiratory tract. however, ozone exposure impairs human performance and induces subjective complaints such as fatigue, lethargy and headache. we studied electrographic aspects of sleep-wake organization in cats, and found that paradoxical sleep was promptly reduced during ozone exposure, followed by a dose-related increase of slow-wave sleep. these findings suggest that h ... | 1992 | 1501789 |
| the human hypothalamus: comparative morphometry and photoperiodic influences. | the concept of the hypothalamus as a distinct neurological entity concerned with a variety of regulatory processes dates back to the end of the 19th century. before 1900 there were only vague intimations of the function of the brain surrounding the third ventricle and these were based primarily on various pathological and assorted clinical observations. since then a large body of evidence has been derived implicating that the hypothalamus contains the control systems which are critically involve ... | 1992 | 1480746 |
| [pathomorphology of experimental candida mycosis]. | an account is given in this paper of evaluated results obtained from over 30 years of research on the pathogenesis and morphology of experimental candidiasis. no success has so far been recorded from efforts to set up a fully valid animal experimental model of all forms of candidiasis in man. models so far can be successfully constructed only for certain links in the process of infection. particular importance, in this context, should be attributed to effects on the organism which would cause im ... | 1992 | 1420105 |
| an animal model for delirium. | this study describes an animal model for delirium comparing rats treated with either saline or atropine. the model was defined by recordings of cortical eegs, maze performance, and behavioral observations. eeg slowing and increased amplitude, difficulty with attention and memory, sleep-wake cycle reversal, and changes in behavior (lack of focused direction, irritability, fluctuating levels of activity, excessive random sniffing) appeared consistent with signs and symptoms seen in human delirium. ... | 1992 | 1461966 |
| association of sleep-wake habits in older people with changes in output of circadian pacemaker. | many elderly people complain of disturbed sleep patterns but there is not evidence that the need to sleep decreases with age; it seems rather that the timing and consolidation of sleep change. we tried to find out whether there is a concurrent change in the output of the circadian pacemaker with age. the phase and amplitude of the pacemaker's output were assessed by continuous measurement of the core body temperature during 40 h of sustained wakefulness under constant behavioural and environment ... | 1992 | 1357348 |
| seasonal variation in the human circadian rhythm: dissociation between sleep and temperature rhythm. | the circadian rhythms of sleep-wakefulness, rectal temperature, and plasma melatonin were measured in 10 healthy male subjects for five consecutive seasons. to minimize direct effects of seasonally changing environmental factors, the subjects stayed in a living facility for 4 days in each season, where ambient temperature, humidity, and social contacts were controlled, while the light intensity of the living room was substantially influenced by natural daylight. seasonal variations were found in ... | 1992 | 1590482 |
| sleep laboratory studies on the single-dose effects of serotonin reuptake inhibitors paroxetine and fluoxetine on human sleep and awakening qualities. | paroxetine is a novel antidepressant drug with selective serotonin (5-ht) reuptake inhibitory properties. in a double-blind placebo-controlled crossover sleep laboratory study the single-dose effects on objective and subjective sleep and awakening qualities were investigated after paroxetine 20, 30 and 40 mg morning doses (px 20, 30, 40), paroxetine 30 mg evening dose, fluoxetine 40 mg morning dose (fx 40) and placebo in 18 healthy young volunteers. the drugs were orally administered in 2-wk int ... | 1991 | 1836894 |
| neuro-endocrine pattern of secretion during the sleep-wake cycle of man. | | 1975 | 1239048 |
| individual differences in human circadian rhythms. | research into individual differences in circadian rhythms is reviewed, particularly morningness-eveningness. it was hypothesised that extraverts would be inclined towards eveningness and introverts towards morningness. forty-eight subjects took regularly their oral temperature. peak times were identified from smoothed temperature curves. results showed that extraverts had a peak time insignificantly later than introverts. re-grouping of the data into the morningness-eveningness dimension, based ... | 1977 | 922076 |
| blind man living in normal society has circadian rhythms of 24.9 hours. | a psychologically normal blind man, living and working in normal society, suffered from a severe cyclic sleep-wake disorder. investigations showed that he had circadian rhythms of body temperature, alertness, performance, cortisol secretion, and urinary electrolyte excretion which were desynchronized from the 24-hour societal schedule. these rhythms all had periods which were longer than 24 hours and indistinguishable from the period of the lunar day. | 1977 | 910139 |
| influence of human presence on sleep-wake patterns in nervous pointer dogs. | | 1978 | 565521 |
| physical changes of the environment and health effects with special reference to water pollution and sanitation in malaysia. | development of a human community are not without changes in its environment. such changes result in either beneficial or adverse effects on human health. in malaysia, in the wake of the new economic policy aimed at the redressing of the poor population and income distribution, development of the nation has brought about various changes in the environment. some of these changes have elevated basic public health problems, while others, particularly new agricultural practices and industrialisation ... | 1979 | 538513 |
| free-running circadian plasma cortisol rhythm in a blind human subject. | the plasma cortisol rhythm in man has been presumed to be an endogenous circadian rhythm, synchronized by some external stimulus to an exact 24-h period. sleep/wake and 'social activity' cycles have been considered as candidates for this synchronizer. previous studies have suggested that the dark/light phase shifts associated with the sleep-wake cycle may be the external synchronizer, rather than the sleep/wake cycle itself. a totally blind, but otherwise normal subject was studied for a period ... | 1979 | 476985 |
| physiological effects of rotational work shifting: a review. | the high cost of capital equipment, demands of the world markets, and continuity requirements of many technological processes have forced industry to operate three-shift, 24-hour days. workers on fixed schedules experience no particular problems from shift work, but those who are shifted periodically can undergo physiological and emotional disturbances. these disturbances occur because most human systems function according to circadian rhythms that can be easily disoriented. the primary cause is ... | 1978 | 627940 |
| circadian dysregulation in abused individuals: a proposed theoretical model for practice and research. | trauma in the form of physical and sexual abuse remains a major issue confronting health professionals and society today. despite the identification of large numbers of children at risk, no studies exist on the association between childhood abuse and the development of acute and long-term disruption of sleep/wake patterns. furthermore, identification of the most effective nursing interventions to restore healthy sleep rhythms is sorely lacking. as a basic human process, sleep follows a circadian ... | 1992 | 1476462 |
| the use of time lapse video recording of sleep-wake behavior in human infants. | | 1976 | 176676 |
| the prevention of viral hepatitis. | studies with heat-inactivated ms-2 serum have indicated that active immunization against hepatitis b infection can be achieved even though the virus has not been cultivated in tissue culture. the development of new biophysical, biochemical and immunological techniques has increased knowledge of the hepatitis b virus and its associated antigens. in the wake of these recent developments the accumulating evidence indicates that active immunization could be achieved by the use of purified hepatitis ... | 1976 | 63266 |
| [circadian rhythms in the endocrine system (author's transl)]. | in four sections, the contribution reviews data on 24-hour variations of cortisol, growth hormone, prolactine, testosterone, lh and fsh in the human plasma. 1) experiments on isolated subjects show that the 24-h variation of cortisol is based on an endogenous circadian rhythm which can be independent from the rhythm of sleep and wakefulness. 2) the various pattern each of which has been described in good correspondence by several groups of authors, suggest a series of hormones with a strong circ ... | 1978 | 651285 |
| effect of growth hormone on human sleep energy. | we wished, by means of power spectrum eeg analysis, to examine rem and delta sleep energy in adults with high and normal plasma growth hormone (gh) concentration. | 1992 | 1563077 |
| visual stimulation and wake-sleep behavior in human neonates. | sixteen male and 16 female infants were exposed to 1 of 4 visual stimulus conditions during pre- and postprandial wakefulness. whereas a nonpatterned gray stimulus minimized the amount of alert inactivity and maximized the amount of subsequent rapid eye movement (rem) sleep, black-and-white checkerboard patterned stimuli produced greater amounts of alert inactivity and correspondingly lesser amounts of subsequent rem sleep. amounts of alert inactivity and of subsequent rem sleep produced by the ... | 1977 | 193748 |
| studies of the 24 hour rhythm of melatonin in man. | in a series of four separate studies of the 24-hour pattern of melatonin secretory function in man, the following results were obtained. sequential measurement of the concentration of melatonin in plasma and urine demonstrated a 24-hour rhythm in which more melatonin is secreted during the sleep-lights off as compared to the waking-lights on period. however, during "free-running" and after an acute phase shift of the sleep-wake cycle, a melatonin rhythm can be dissociated from the sleep-lights o ... | 1978 | 288856 |
| [circadian analysis of sleep, rectal temperature and immunological and endocrinological variables in sleeping sickness: preliminary study]. | a multidisciplinary study was conducted in 8 patients with neurological human african trypanosomiasis. the sleep-wake cycle followed an ultradian pattern which was more pronounced in patients with more severe symptoms. the eeg trace was consistently interrupted by numerous cyclic activation patterns with k complexes, rapid low amplitude elements and slow high voltage elements. circadian rhythmicity was also disturbed in other physiological (rectal temperature), immunological (interleukins) or ho ... | 1990 | 2208457 |
| sleep in human narcolepsy revisited with special reference to prior wakefulness duration. | sleep of 11 narcoleptic subjects was recorded on baseline and after 16 and 24 hours of prior wakefulness (16 and 24 hours sleep deprivation). eleven sex- and age-matched control subjects were recorded for comparisons. all recordings in narcoleptic subjects were characterized by frequent sleep onset rapid eye movement (rem) episodes, increased amounts of wake time after sleep onset and low sleep efficiencies. mean total sleep time (tst) was significantly decreased in narcoleptic subjects after sl ... | 1992 | 1519010 |
| travel at low energetic cost by swimming and wave-riding bottlenose dolphins. | over the past 50 years there has been much speculation about the energetic cost of swimming and wave-riding by dolphins. when aligned properly in front of the bow of moving ships in the stern wake of small boats, on wind waves, and even in the wake of larger cetaceans, the animals appear to move effortlessly through the water without the benefit of propulsive strokes by the flukes. theoretically, body streamlining as well as other anatomical and behavioural adaptations contribute to low transpor ... | 1992 | 1538760 |
| melatonin: a major regulator of the circadian rhythm of core temperature in humans. | the circadian rhythm of core body temperature (btc), with maxima during the day and minima at night, is normally coupled with the sleep-wake cycle. pineal melatonin secretion occurs contemporaneously during the nighttime hours and is mediated by the activation of beta-adrenergic receptors during darkness. the hypothesis that nocturnal melatonin secretion may be involved in the regulation of the human circadian btc rhythm was examined. the temporal relationship between melatonin and the circadian ... | 1992 | 1639946 |
| battered bottom lines: the impact of eroding pharmaceutical discounts on health-care institutions. | for several years, the american society of hospital pharmacists (ashp) has voiced concern about the impact of federally mandated changes on the pharmaceutical products marketplace. since this marketplace is relatively inelastic, manipulating one segment in the interest of cost efficiencies is likely to result in price increases in other segments. that manipulation could come through such decisions as a "one-price" policy for pharmaceuticals, mandatory rebates for certain segments of the marketpl ... | 1992 | 1595750 |
| arm pain in the workplace. a small area analysis. | in the mid-1980s, use-related arm pain was recognized as a major issue for worker health and workplace safety. national policy targeted these "cumulative trauma disorders," "overuse syndromes," and "motion illnesses" for a "special emphasis program" by the occupational safety and health administration, a federal regulatory agency. the program begins with case recognition to identify the responsible ergonomic hazards with the goal of mandating ergonomic remedies. this report is a small area analy ... | 1992 | 1597765 |
| seroepidemiology of arboviruses among seabirds and island residents of the great barrier reef and coral sea. | duplicate neutralization tests were done on 401 avian and 101 human sera from island residents collected in the coral sea and on australia's great barrier reef against 19 known arboviruses. antibodies to a potentially harmful flavivirus, gadget's gully virus, were equally present (4%) in both avian and human sera. antibodies to another flavivirus, murray valley encephalitis, and an ungrouped isolate, csiro 1499, were also present in both populations with non-significantly different incidences. a ... | 1991 | 1657626 |
| granuloma annulare and disseminated herpes zoster. | a 71-year-old man was admitted to the wake forest university/baptist hospital medical center on february 1, 1989, with pharyngitis and a cutaneous eruption that began that day. the past history was significant for a diagnosis of chronic lymphocytic leukemia (cll) made in 1984, and for longstanding hypertension, severe coronary artery disease, and prostatic hypertrophy. the patient had required no therapy for his cll until august, 1988, when he developed hemolytic anemia and was treated with oral ... | 1992 | 1737692 |
| cerebral glucose utilization during stage 2 sleep in man. | using [18f]fluorodeoxyglucose method and positron emission tomography, we performed paired determinations of the cerebral glucose utilization at one week intervals during sleep and wakefulness, in 12 young normal subjects. during 6 of 28 sleep runs, a stable stage 2 sws was observed that fulfilled the steady-state conditions of the model. the cerebral glucose utilization during stage 2 sws was lower than during wakefulness, but the variation did not significantly differ from zero (mean variation ... | 1992 | 1611488 |
| circadian rate variation in rate-adaptive pacing systems. | by mimicking the natural rate slowdown during sleep, a pacing system can enhance patient comfort while improving device longevity. a new family of rate-adaptive pacemakers accomplishes this circadian rate variation by modeling the patient's sleep-wake cycle using a time-of-day clock inside the device. furthermore, to account for minor variations in the patient's sleep-wake cycle, sensor data can be used to automatically adapt the starting and stopping points of this change in rate. using the mod ... | 1990 | 1704544 |
| influence of melatonin treatment on human circadian rhythmicity before and after a simulated 9-hr time shift. | the hormone melatonin is currently proposed by some investigators to be an efficient means for decreasing the impairing effects of jet lag. eight healthy male subjects, aged 20 to 32, underwent a 9-hr advance shift in the isolation facility of our institute during two periods each of 15 days' duration. in a double-blind, crossover design, subjects took either melatonin or placebo at 1800 hr local time for 3 days before the time shift and at 1400 hr for 4 days afterwards. the time shift was simul ... | 1991 | 1773094 |
| development of circadian sleep-wake rhythms in preterm and full-term infants. | we have compared the roles of neurologic maturity and environmental time cues in the development of the entrained circadian sleep-wake rhythm in the preterm and term human infant. the preterm infants (n = 19) spent some time after birth in a hospital nursery with no environmental time cues, whereas the term infants (n = 22) were exposed from birth to a cyclical light and dark environment with one major caregiver. the circadian sleep-wake rhythm in the preterm infants entrained after a similar ti ... | 1991 | 1852533 |
| [circadian variation in alertness, readiness for work and work efficiency]. | among various rhythmic processes with different frequencies (periods), which are present in the human organism, for normal functioning the most important are the rhythms with a cycle length of about 24 hours (termed circadian rhythms). circadian rhythms have been confirmed at all levels of physiological functions: from subcellular and cellular mechanisms, to the organic systems and organism on the whole. in normal everyday circumstances the rhythmic processes in the human organism are synchronis ... | 1991 | 1854261 |
| automated staging of sleep in cats using neural networks. | manual staging of sleep based on visual eeg criteria is a laborious and time-consuming task. in an effort to automate sleep staging, we have developed a neural network that 'learns' to stage sleep on the basis of wave band count data alone, in the cat. wave band count data are collected on a microcomputer, using period-amplitude analysis. delta waves, spindle bursts, ponto-geniculo-occipital (pgo) waves, electro-oculogram (eog), basal electromyogram (emg) amplitude, and movement artifact amplitu ... | 1991 | 1713552 |
| research on sleep, circadian rhythms and aging: applications to manned spaceflight. | disorders of sleep and circadian rhythmicity are characteristic of both advancing age and manned spaceflight. sleep fragmentation, reduced nocturnal sleep tendency and sleep efficiency, reduced daytime alertness, and increased daytime napping are common to both of these conditions. recent research on the pathophysiology and treatment of disrupted sleep in older people has led to a better understanding of how the human circadian pacemaker regulates the timing of the daily sleep-wake cycle and how ... | 1991 | 1915692 |
| solidarity and aids: introduction. | perhaps more than any other disease in recent history, aids has taught a cruel and crucial lesson: the constraints on our response to this epidemic are as deep as our denial, as entrenched as the inequities that permeate our society, as circumscribed as our knowledge, and as unlimited as our compassion and our commitment to human rights. elaborating on these themes, the final three articles in this special section on aids consider three widely divergent yet intimately connected topics: aids in c ... | 1991 | 1917210 |
| serotonin and behavior: emphasis on motor control. | electrophysiologic studies of brain serotonergic neurons in behaving animals indicate that their activity is closely related to the sleep-wake-arousal cycle and to certain specific types of repetitive motor activity. a variety of other environmental and physiologic manipulations are ineffective in altering the activity of this neurochemical system. an attempt is made to relate these results to well-known involvement of brain serotonin in human affective disorders. | 1991 | 1752856 |
| patterns of daily allocation of sleep periods: a case study in an amazonian riverine community. | few works already carried out have examined the relative role of genetic and external factors on the determination of the rhythmicity of the human sleep/wake cycle. in order to make a preliminary approach in this field, we investigated the diversity of patterns of allocation of sleep periods among 29 families living at the combu island, a socioculturally very homogeneous human group of the brazilian amazon. the individuals were interviewed through a questionnaire designed by horne and ostberg (1 ... | 1991 | 1935416 |
| absence epilepsy and the level of vigilance in rats of the wag/rij strain. | in man, a relationship exists between sleep-wake states and absence epilepsy. during wakefulness, spike-wave discharges predominantly occur when the level of vigilance is not high, while during sleep they have a preference to occur during slow-wave sleep. during this latter type of sleep, spike-wave discharges prevail in periods where slow-wave sleep is light. in a series of experiments, the wag/rij rat model for absence epilepsy was characterized with respect to the relationships between the le ... | 1991 | 1906586 |
| conceiving a child to save a child: reproductive and filial ethics. | i conclude that mary and abe's decision to conceive a child to save a child does not impose harm on persons or on relationships in the family. nor does it evince a lack of respect for the child they have conceived. the ethical guidelines that support this conclusion can now be summarized. first, actions should not depersonalize or otherwise endanger personal relationships. second, although ideally personal relationships are initiated and continued for their own sake, after a personal relationshi ... | 1990 | 2131079 |
| atrial natriuretic peptide, renin activity, aldosterone, urine volume and electrolytes during a 24-h sleep-wake cycle in man. | to investigate the diurnal variation in the plasma atrial natriuretic peptide (anp) concentrations and its relation to renin activity, aldosterone, urine volume and electrolytes, blood samples from six healthy male subjects were collected and blood pressure and heart rate recorded every 4 h during a 24-h sleep-wake period. systolic blood pressure and heart rate were at the lowest during sleep. plasma anp, extracted on sep-pak cartridges and measured by radioimmunoassay, had the highest concentra ... | 1990 | 2141447 |
| effects of moclobemide on sleep in healthy human subjects. | ten healthy, normal subjects (5 male and 5 female) aged 20-28 years participated in this experimental study of the effect of moclobemide on sleep. the design consisted of 2 sessions of 5 nights each, comprising 1 adaptation night, 2 nights on placebo and 2 inputs of moclobemide 4 mg/kg (session b). the 2 sessions were separated by at least 15 days and their order was balanced and randomized. during the last 4 nights of each session, sleep parameters were recorded throughout the night according t ... | 1990 | 2248081 |
| human daily rhythms measured for one year. | four human subjects recorded their wake-up and to-sleep times for one year each. the data were plotted to display individual circadian rhythms and the data were analyzed statistically. first, individuals had characteristic patterns in which visible changes in the patterns were observed mainly when time zones were changed because of travel. second, the months with the latest wake-up and latest to-sleep times concentrated around the winter solstice; the months with the earliest wake-up and earlies ... | 1990 | 2255734 |
| relationship between duration of spinal cord ischemia and postoperative neurologic deficits in animals. | stagnara wake-up tests, blood flow measures, somatosensory evoked potentials (seps), and neurogenic-motor evoked potentials (nmeps) were elicited from 20 hogs before and after spinal cord overdistraction at l3-l4. overdistraction was maintained from 5 to 30 minutes after loss of nmeps. results suggest that the longer the duration of overdistraction the greater the likelihood of paraplegia. blood flow measures indicated that reduced perfusion was greatest at the distraction site but extended prox ... | 1990 | 2259969 |
| entrainment of circadian rhythms with 26-h bright light and sleep-wake schedules. | subjects followed a 26-h sleep-wake schedule and were exposed to various light patterns while living at home exposed to the conflicting 24-h zeitgebers. in one protocol, a 26-h light pattern containing evening bright light was compared with a natural-light-only pattern. in another protocol, the evening-light pattern was compared with a morning-light pattern. rectal temperature was continuously measured. sleep times were estimated from daily sleep logs. the sleep times of most subjects conformed ... | 1990 | 2260729 |
| short latency ocular-following responses in man. | the ocular-following responses elicited by brief unexpected movements of the visual scene were studied in human subjects. response latencies varied with the type of stimulus and decreased systematically with increasing stimulus speed but, unlike those of monkeys, were not solely determined by the temporal frequency generated by sine-wave stimuli. minimum latencies (70-75 ms) were considerably shorter than those reported for other visually driven eye movements. the magnitude of the responses to s ... | 1990 | 2278939 |
| human circadian rhythms and exercise. | many biological functions change cyclically over a 24-h period, such cycles being referred to as circadian rhythms. the major rhythms of relevance to examine performance are those of body temperature and the sleep-wake cycle. many components of exercise performance are closely related to the body temperature curve which peaks in the early evening. exercise with predominantly neuromotor and cognitive components depend also on the underlying sleep-wake cycle. some performance measures are subject ... | 1990 | 2286092 |
| vitamin b12 treatment for sleep-wake rhythm disorders. | vitamin b12 (vb12) was administered to two patients suffering for many years from different sleep-wake rhythm disorders. one patient was a 15-year-old blind girl suffering from a free-running sleep-wake rhythm (hypernychthemeral syndrome) with a period of about 25 h. in spite of repeated trials to entrain her sleep-wake cycle to the environmental 24-h rhythm, her free-running rhythm persisted for about 13 years. when she was 14 years old, administration of vb12 per os was started at the daily do ... | 1990 | 2305167 |
| the unknown human infant. | what is physiological? it is often difficult to answer this kind of question in the field of human reproduction. that is why we propose to take, as a reference, a population of one hundred infants whose lifestyle is, in many respects, different from the standard western norm. they were born at home without any drugs, share the mother's bed, were breastfed for more than a year, and so on. this study raises questions such as: --is the neonatal loss of weight physiological? --what are the physiolog ... | 1990 | 2310482 |
| exposure to bright light and darkness to treat physiologic maladaptation to night work. | working at night results in a misalignment between the sleep-wake cycle and the output of the hypothalamic pacemaker that regulates the circadian rhythms of certain physiologic and behavioral variables. we evaluated whether such physiologic maladaptation to nighttime work could be prevented effectively by a treatment regimen of exposure to bright light during the night and darkness during the day. we assessed the functioning of the circadian pacemaker in five control and five treatment studies i ... | 1990 | 2325721 |
| convective heat transfer measured directly with a heat flux sensor. | a heat flux disk has been developed that directly measures the convective heat transfer in w/m2. when the sensor is calibrated on an aluminum cylinder, the calibration constant obtained is greatest in still air. as air movement increases, the calibration constant is reduced with increasing convective heat transfer coefficient, 0.5%.w-1.m2.k. the influence of wind on the calibration value is greatly reduced when the sensor is attached to a surface with lower thermal conductivity. the local convec ... | 1990 | 2341350 |
| cerebral glucose utilization during sleep-wake cycle in man determined by positron emission tomography and [18f]2-fluoro-2-deoxy-d-glucose method. | using the [18f]fluorodeoxyglucose method and positron emission tomography, we studied cerebral glucose utilization during sleep and wakefulness in 11 young normal subjects. each of them was studied at least thrice: during wakefulness, slow wave sleep (sws) and rapid eye movement sleep (rems), at 1 week intervals. four stage 3-4 sws and 4 rems fulfilled the steady state conditions of the model. the control population consisted of 9 normal age-matched subjects studied twice during wakefulness at, ... | 1990 | 2350676 |
| an automated technique for measuring the recovery cycle of human nerves. | action potentials conducted along a nerve fiber leave in their wake consistent alterations in excitability, including the absolute and relative refractory periods, a supernormal period (snp) and a late phase of subnormality. we describe an automated technique for reliably determining the recovery cycle of human sensory nerve fibers by delivering series of paired stimuli and precisely measuring the latencies (to within 0.5 microseconds) of the compound action potentials. the recovery cycle can be ... | 1990 | 2385261 |
| ultradian rhythmic models of blood pressure variation in normal human daily life. | to examine levels and variance structure of systolic blood pressure (sbp), diastolic blood pressure (dbp) and heart rate (hr), we measured those 3 variables every 7.5 min for 24 h (approximately 192 samples each subject) by ambulatory monitoring in 2 nominated groups of normal volunteers: younger (y; 8 men, 5 women, 24-44 years) and older (o; 13 men, 12 women, 50-95 years). y and o did not differ in either sleep or wake means for hr and dbp. mean sbp in o was 17 mm hg higher than in y during wak ... | 1990 | 2394198 |
| differential effects of prior wakefulness and circadian phase on nap sleep. | studies of experimentally altered human sleep-wake cycles have shown that rapid eye movement (rem) sleep propensity exhibits a circadian periodicity, while slow wave sleep (sws) is primarily responsive to the duration of prior wakefulness. what is not known is the extent to which rem sleep continues to show a circadian pattern under intense sleep pressure, and the extent to which sws remains responsive to prior wakefulness at opposite phases of the circadian cycle. these questions were addressed ... | 1986 | 2427317 |
| comparison of body temperature rhythms between healthy elderly and healthy young adults. | the fact that the elderly are usually aware of early sleep onset and early morning awakening shows that the phase of sleep-wake rhythms in the elderly is more advanced than that in young adults. since it has been suggested that human sleep onset, morning awakening, sleep period and depth of sleep are highly influenced by body temperature rhythms, rectal temperature rhythms were analyzed in 7 healthy elderly and 7 healthy young adults under the condition with time cue. although a significant 24-h ... | 1991 | 1753488 |
| evidence for excessive sleepiness in canine narcoleptics. | six genetically narcoleptic dogs, as well as 6 age- and breed-matched control dogs, were recorded continuously for 24 h to compare sleep/wake patterns and to determine whether narcoleptic dogs exhibit evidence of excessive sleepiness. compared with controls, the affected animals showed a substantial reduction in wakefulness and a significant increase in time spent in the drowsy state. total nrem sleep and total sleep time (nrem and rem sleep) in the 2 groups, however, were very similar. results ... | 1986 | 2428595 |
| potassium affects actigraph-identified sleep. | the present study examines the effects of potassium supplementation on sleep quality and phase, as indirectly inferred from wrist actigraphy and sleep logs, in normal young males on a low-potassium diet. a randomized, double-blind, placebo-controlled, counterbalanced crossover design compared 1 wk of oral potassium chloride supplements (96 meq/day) to 1 wk of identical placebo capsules. outcome measures were taken from sleep logs and wrist actigraphy. sleep was indirectly inferred from wrist-act ... | 1991 | 1947601 |
| diurnal and ultradian rhythms in human endocrine function: a minireview. | rapidly accumulating evidence indicates that every hypothalamo-pituitary axis is influenced by both sleep (irrespective of the time of day when it occurs) and circadian rhythmicity (irrespective of the sleep or wake condition). circadian effects seem to be exerted by a modulation of the amplitude of secretory pulses. sleep may affect pulse frequency. recent studies indicate that this complex temporal organization is not limited to pituitary and pituitary-dependent hormones but also underlies glu ... | 1990 | 1965834 |
| disruption of human circadian and cognitive regulation following a discrete hypothalamic lesion: a case study. | we report a patient with rostral hypothalamic damage that significantly disrupted temporal patterning of the sleep-wake cycle, body temperature, and cognitive and behavioral functioning. the findings suggest that the suprachiasmatic region of the hypothalamus is important for the circadian control of human behavior, and that circadian organization may be essential for normal cognitive functioning. | 1991 | 2027490 |
| plague and glasnost. first information about human cases in the ussr in 1989 and 1990. | in october 1989 the first case of plague death in the ussr was reported to who. this occurrence in man did not surprise plague experts. the country has extensive enzootic areas and the persistence of natural foci, which can be silent for many years, has been well studied. it is known that the plague bacillus can survive and multiply in the soil of rodent burrows and restart local or more extensive transmissions in carrier animals. isolated cases in man can remain accidental or they may signal a ... | 1990 | 2076913 |
| synchronisation of a disturbed sleep-wake cycle in a blind man by melatonin treatment. | | 1988 | 2895305 |
| effects of sex, thyro-parathyroidectomy, and light regime on levels and circadian rhythms of wheel-running in rats. | intact and thyro-parathyroidectomized (tpx) sprague-dawley rats of both sexes were observed for 24 days under a 12:12 light:dark cycle (entrainment), followed by 20 days in constant dim red light (free-run). circadian periods and levels of wheel-running activity were examined. intact females and tpx males were significantly more active and had significantly shorter free-running circadian periods than intact males, and the effects of tpx in females were different from those in males. circadian pe ... | 1989 | 2623053 |
| weekly phase shifts of rhythms self-reported by almost feral human students in the usa and spain. | eleven students in the usa and fifteen students in spain wrote their wake-up and to-sleep times on forms for a month. the subjects reported large day-to-day phase shifts of magnitude comparable to those of travelers and shiftworkers. all individuals exhibited some large phase shifts of their day-to-day wake-up and to-sleep times (largest shift average, 4.54 hours; range, -12.7 to +13.9 hours). the students had daily cycles and weekly cycles in their wake-up and to-sleep times. synchrony (entrain ... | 1989 | 2623064 |
| entrainment of a free-running human with bright light? | the case of a 40-year-old sighted woman with free-running sleep-wake and melatonin rhythms is presented. the subject was studied for 102 days. during the pre-treatment period, both the sleep-wake and melatonin rhythms had a period of 25.1 hr, similar to the average period of humans living in temporal isolation. treatment consisted of bright artificial light exposure (2500 lx vita-lite) for 2 hr each day upon awakening. clock time of light exposure was held constant for 6 days and then slowly adv ... | 1989 | 2627721 |
| [effect of shift interval for the clinical nurse with respect to circadian rhythm]. | circadian rhythm is entrained in the 24-hour time interval by periodic factors in the environment, known as zeitgeber. but most rotating work schedules are outside the range of the entrainment of the pacemaker timing the human circadian sleep-wake cycle. it has been postulated that physiological and emotional disturbances occur in most human functions when the circadian rhythm is disturbed. so application of circadian principles to the design of shift schedules can aid in maintaining the tempora ... | 1991 | 1921097 |
| high-level expression of human dihydropteridine reductase (ec 1.6.99.7), without n-terminal amino acid protection, in escherichia coli. | the cdna coding for human dihydropteridine reductase [dahl, hutchinson, mcadam, wake, morgan & cotton (1987) nucleic acids res. 15, 1921-1936] was inserted downstream of tandem bacteriophage lambda pr and pl promoters in escherichia coli vector pce30. since pce30 also expresses the lambda c1857ts gene, transcription may be controlled by variation of temperature. the recombinant plasmid in an e. coli k12 strain grown at 30 degrees c, then at 45 degrees c, directed the synthesis of dihydropteridin ... | 1989 | 2673215 |
| current status of occupational safety and health administration infection control regulations. | in the wake of widespread hepatitis b, human immunodeficiency virus, and other bloodborne infections, organizations of health care employees have asked the occupational safety and health administration (osha) to address the reduction of infection risks encountered in the delivery of private and institutional health care. the task is much the same as reducing job related risks in industry. this article explains and reviews interim osha infection control regulations that apply to dentistry now, an ... | 1991 | 2032577 |
| [the sleep-wake rhythm of the fetus]. | our work refers to a body of studies carried out by sonargram observation, which allowed us to study fetal movements in real time. these fetuses were studied not only as parameters of correct neurobiological maturity but also from the psychological interest which looks for the beginning of thinking based on the question: when and how does the thought process begin in biological matter? the study comparing the movement of fetuses and new-born babies to psychoanalytical research (which have been d ... | 1988 | 3045847 |
| use of benzodiazepines to manipulate the circadian clock regulating behavioral and endocrine rhythms. | extensive studies have now been carried out demonstrating that the systemic administration of the short-acting benzodiazepine, triazolam, can have pronounced effects on both behavioral and endocrine circadian rhythms. for example, three daily injections of triazolam can phase-advance the circadian rhythm of pituitary luteinizing hormone release and locomotor activity by about 2-3 h in female hamsters maintained in constant light. triazolam has also been found to facilitate the rate of reentrainm ... | 1989 | 2656469 |
| changes in vasopressin neurons and fibers in aging and alzheimer's disease: reversibility in the rat. | the neuropeptide vasopressin (vp) is released from the neurohypophysis into the circulation where it acts as antidiuretic hormone on the kidney. in addition, vp is present in nerve cells and fibers in several areas in the rodent and primate brain where it acts as a neurotransmitter or neuromodulator. in the human brain a marked decrease in total cell number and vp cell number was observed in senescence in the suprachiasmatic nucleus, the hypothalamic nucleus regulating circadian rhythms. this de ... | 1989 | 2690091 |
| effects of daytime noise load on the sleep-wake cycle and endocrine patterns in man. iii. 24 hours secretion of free and sulfate conjugated catecholamines. | this study was designed to re-examine the circadian profiles of dopamine, noradrenaline and adrenaline in the plasma and to investigate the influence of daytime noise stress on these profiles. twelve subjects participated in two experimental series of 60 h; during one they were exposed to 85 db(a) industrial noise from 9:00 to 21:00 h. blood samples were taken for a period of 24 h at 20 min intervals and the plasma levels of the free and the sulfoconjugated catecholaminergic compounds were simul ... | 1988 | 3215733 |
| electron microscopy and antigenic studies of uncharacterized viruses. i. evidence suggesting the placement of viruses in families arenaviridae, paramyxoviridae, or poxviridae. | during approximately 35 years, investigators in various laboratories studying arbovirus ecology and epidemiology accumulated many virus isolates, more than 60 of which were not characterized or placed in taxa. by a combination of electron microscopic and antigenic studies we collected information sufficient to provisionally classify 60 isolates. electron microscopic observations suggest that 20 are members of the virus family bunyaviridae, 20 rhabdoviridae, 14 reoviridae, one togaviridae, one pa ... | 1989 | 2690775 |
| persistence of asymmetry in nonaxisymmetric entry flow in a circular cylindrical tube and its relevance to arterial pulse wave diagnosis. | in an experiment motivated by the study of arterial blood flow along the lines suggested by the traditional chinese medicine, the flow in a pipe whose lumen was blocked by a semi-circular plug two tube-diameters long was visualized by suspended particles, recorded by cinematography, and analyzed digitally. the reynolds number was in the range of 100 to 450 based on the pipe diameter, similar to that of blood flow in the radial artery in the arms of man. the blockage was found to have a profound ... | 1989 | 2747231 |
| sleep on the night shift: 24-hour eeg monitoring of spontaneous sleep/wake behavior. | the present study sought to objectively describe the spontaneous sleep/wakefulness pattern of shift workers during a 24-hour period. portable medilog tape-recorders were used for ambulatory eeg monitoring of 25 male papermill workers (25-55 years) during days with night and afternoon work. the results showed that sleep after night work was two hours shorter than after afternoon work. the sleep reduction affected mainly stage 2 and rem sleep while slow wave sleep was unchanged. in connection with ... | 1989 | 2756085 |
| bright white light does not improve narcoleptic symptoms. | bright white light (500lx) for 4 h/day was applied to seven narcoleptic patients (age 47-65 years, mean 55 years). the effects of the light on the disturbed sleep-wake cycle in narcoleptics were investigated by the measurement of the following parameters: (1) excessive daytime sleepiness and sustained attention (multiple sleep latency test); (2) rest-activity cycles; (3) self-ratings (mood, anxiety, tiredness); (4) urinary cycles of 6-oh melatonin sulphate and cortisol; (5) sleep eeg. treatment ... | 1989 | 2759154 |
| effects of sleep deprivation on human immune functions. | the effect of 40 h of wakefulness on a variety of immunological parameters in the peripheral blood from 10 normal male subjects was studied. sleep deprivation led to enhanced nocturnal plasma interleukin 1-like and interleukin 2-like activities. the rise in nocturnal response of lymphocytes to pokeweed mitogen stimulation during a normal 24 h sleep-wake cycle was delayed by sleep deprivation, but the response to the phytohemagglutinin mitogen was unaffected. with resumed nocturnal sleep, there w ... | 1989 | 2785942 |
| the pathologist's view of lyme disease. | lyme disease is a multisystem disease caused by the spirochete borrelia burgdorferi and is transmitted to humans primarily through ixodid ticks. the clinical spectrum of the disease is continuing to expand while in its wake the pathology and histopathologic manifestations are being uncovered. we review the pathology of lyme disease in man beginning with the tick bite. we present the pathologic changes of the rash, erythema migrans, as well as the neurologic, cardiac, and arthritic changes of the ... | 1989 | 2690468 |
| regression models for the estimation of circadian rhythms in the presence of effects due to masking. | the estimation of human circadian rhythms from experimental data is complicated by the presence of "masking" effects associated with the sleep-wake cycle. the observed rhythm may include a component due to masking, as well as the endogenous component linked to a circadian pacemaker. in situations where the relationship between the sleep-wake cycle and the circadian rhythm is not constant, it may be possible to obtain individual estimates of these two components, but methods commonly used for the ... | 1989 | 2706704 |
| masking of the circadian rhythms of heart rate and core temperature by the rest-activity cycle in man. | heart rate and core temperature are elevated by physical activity and reduced during rest and/or sleep. these masking effects may confound interpretation of rhythm waveforms, particularly in situations where the rest-activity rhythm has a different period from that of the core temperature rhythm. such desynchronization often occurs temporarily as an individual adjusts to a new work shift or to a new time zone following rapid transmeridian travel, making it difficult to assess the impact of such ... | 1986 | 2979578 |
| effects upon circadian rhythmicity of an alteration to the sleep-wake cycle: problems of assessment resulting from measurement in the presence of sleep and analysis in terms of a single shifted component. | experiments were performed upon groups of three or four human subjects in an isolation chamber (total n = 14). subjects lived initially on a conventional lifestyle and then delayed their hours of sleep by 8 hr (so mimicking some aspects of nightwork) for 2 or 5 days. they also performed two constant routines--protocols designed to minimize any effects due to the environment, mealtimes, and activity. regular samples of urine were taken when subjects were awake, and were analyzed for sodium, potas ... | 1988 | 2979629 |
| jet-lag and human performance. | the desynchronisation of an athlete's physiological and psychological cycles has adverse effects on his/her performance. the primary cause of dysrhythmia in an athlete is jet-lag, which is a rapid displacement across the earth's time zones and is often experienced while competing in international events and in continental leagues. general symptoms which arise from dysynchronization include malaise, appetite loss, tiredness during the day and disturbed sleep. the specific symptoms resulting from ... | 1989 | 2692117 |
| a single human gene encoding multiple tyrosine hydroxylases with different predicted functional characteristics. | catecholaminergic systems in discrete regions of the brain are thought to be important in affective psychoses, learning and memory, reinforcement and sleep-wake cycle regulation. tyrosine hydroxylase (th) is the first enzyme in the pathway of catecholamine synthesis. its importance is reflected in the diversity of the mechanisms that have been described which control its activity; th levels vary both during development and as a function of the activity of the nervous system. recently, we deduced ... | 1987 | 2882428 |
| marked blood pressure fluctuations during narcoleptic attacks alternating with abnormal wakefulness: effects of treatment with clonidine. | a middle-aged man was admitted to our department because of sleep-wake cycle disorders (alternating hypersomnia and sleeplessness), bipolar behavioural disturbances and marked fluctuations in blood pressure and heart rate. neither evident precipitating stimuli nor an obvious cause for his illness were found. when tests that normally activate intrinsic autonomic responses were performed, two distinct circulatory patterns were recognized. during hypersomnia (phase a), cardiovascular reflex activit ... | 1989 | 2539291 |
| mechanisms of seizure suppression during rapid-eye-movement (rem) sleep in cats. | rem sleep is the most antiepileptic state in the sleep-wake cycle for human generalized epilepsy, yet the neural mechanism is unknown. this study verified the antiepileptic properties of rem sleep in feline generalized epilepsy and also isolated the responsible factors. conclusions are based on 20 cats evaluated for generalized eeg and motor seizure susceptibility before and after dissociation of specific rem sleep components. bilateral electrolytic lesions of the medial-lateral pontine tegmentu ... | 1989 | 2598045 |
| chronic clorgyline treatment of syrian hamsters: an analysis of effects on the circadian pacemaker. | clorgyline, a type a monoamine oxidase inhibitor with antidepressant properties when administered to depressed patients, is often associated with disturbances of the human sleep-wake cycle. in order to assess its effects on the mammalian circadian system, this drug was administered chronically to syrian hamsters. it was found to affect the hamster circadian system in four specific ways. clorgyline increased the intrinsic period of wheel-running activity, altered the phase response curve to brief ... | 1988 | 2979641 |
| the mathematical structure of the human sleep-wake cycle. | | 1987 | 2979668 |
| brain temperature changes coupled to sleep states persist during interleukin 1-enhanced sleep. | the effects of human interleukin 1 (il 1) on the architecture of rabbit sleep-wake cycles and brain temperature (tbr) changes coupled to states of vigilance were examined. cerebral intraventricular infusion of il 1 induced increased slow-wave sleep (sws), increased electroencephalographic slow-wave (0.5-4 hz) amplitudes, and fever. heat-inactivated il 1 failed to elicit these responses. il 1 also significantly inhibited rapid-eye-movement (rem) sleep; however, inactivated il 1 also reduced rem s ... | 1986 | 3484616 |
| short-term sleep laboratory studies with cinolazepam in situational insomnia induced by traffic noise. | in a double-blind, placebo-controlled sleep-laboratory study the short-term effects of cinolazepam--a recently introduced 1,4 benzodiazepine with a half-life of 9 h--on the all-night sleep, morning awakening and early morning behaviour were investigated in 20 young normal subjects, whose sleep was experimentally disturbed by nocturnal traffic noise. the latter was prerecorded on tape and reproduced by loud speakers throughout the night with a sound pressure level of 68-90 db(a) (energy equivalen ... | 1987 | 2889679 |
| human sleep and circadian rhythms: a simple model based on two coupled oscillators. | we propose a model of the human circadian system. the sleep-wake and body temperature rhythms are assumed to be driven by a pair of coupled nonlinear oscillators described by phase variables alone. the novel aspect of the model is that its equations may be solved analytically. computer simulations are used to test the model against sleep-wake data pooled from 15 studies of subjects living for weeks in unscheduled, time-free environments. on these tests the model performs about as well as the exi ... | 1987 | 3625054 |
| differential effects of flunitrazepam on human sleep in combination with flumazenil. | the experiments reported here were designed to characterize in detail the spectrum of activity of flunitrazepam in human sleep. the direct and residual effects of flunitrazepam, as well as the antagonism by flumazenil, an antagonist of benzodiazepine receptors, were studied in 28 normal subjects recorded in the sleep laboratory. the five categories of variables--sleep-wake balance, sleep organization, orthodox sleep, phasic events in sleep, and sleep waveforms--were all modified by flunitrazepam ... | 1989 | 2496452 |
| [isolation of islands of langerhans from the human adult pancreas]. | nine of 38 islet isolation experiments, using the duct collagenase technique, were selected for quality checks on isolated islet tissue. pancreas was harvested, following aortic multi-organ perfusion. the total number of islets isolated amounted to 112,461 +/- 11,828 in 13.7 ml of suspension on average. in vitro secretion of beta cells was increased by a factor of 3.8 in response to glucose stimulation. isolated islets in morphologically intact condition were detected by histological investigati ... | 1988 | 3148248 |
| bacterial peptidoglycans as modulators of sleep. ii. effects of muramyl peptides on the structure of rabbit sleep. | sleep-promoting substances derived from human urine and rabbit brain were identified as muramyl peptides (mps). we report in the accompanying paper that in the molecular structure of mps, the 1,6-anhydro muramic acid moiety of mps is important for enhancement of slow-wave sleep (sws) in rabbits. here, we document more extensively the effects of one mp: 1,6-anhydro-muramyl-alanyl-glutamyl-diaminopimelyl-alanine (amtp for anhydro-muramyl tetrapeptide) on sleep structure of rabbits. amtp significan ... | 1987 | 3103866 |
| ciliary defects: cell biology and clinical perspectives. | considerable progress has been made in achieving a perspective of the pathophysiology of ciliary defects in human disease in the interval between siewert's and kartagener's early descriptions of ks. not only have we achieved a better understanding of some of the mechanisms involved in the pathogenesis of congenital ciliary syndromes, but also we have come to appreciate a new spectrum of ciliary defects, those of acquired etiology. the advent of modern electron microscopy has been a significant e ... | 1988 | 3055856 |