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Do weekly and fast-rotating shiftwork schedules differentially affect duration and quality of sleep?
F. M. Fischer Antonio Castro Bruni Adelaide Berwerth Claudia Roberta Castro Moreno Rosaneli Lima Fernandez Claudia Riviello 《International archives of occupational and environmental health》1997,69(5):354-360
Characteristics of shiftwork schedules can have distinct impacts on workers’ sleep. This report presents comparisons of the
effects of two different shiftwork schedules on duration and quality of the main sleep episodes in comparable worker populations
at two different petrochemical plants. No significant differences were found for sleep duration in comparing the two plants.
However, within each plant’s shift cycles, morning and night shifts showed shorter sleep durations than all other workdays
and days off. Quality of sleep was perceived as lowest for night shifts of both plant schedules, and of lesser quality for
weekly than for fast-rotating shifts. These results support recommendations for reducing the number of consecutive nights
of shiftwork. However, before recommending any optimal shift schedule, interactions of sleep duration and quality with shift
schedules need much further evaluation.
Received: 18 December 1995/Accepted: 18 July 1996 相似文献
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M C van Dam-Mieras A D Muller V W van Hinsbergh W J Mullers P H Bomans C A Bruggeman 《Thrombosis and haemostasis》1992,68(3):364-370
The report describes the effect of an in vitro infection of human umbilical vein endothelial cells with human Cytomegalovirus (CMV). The parameters studied are cellular procoagulant activity, secretion of plasminogen activator inhibitor (PAI-1) and urokinase-type plasminogen activator (u-PA), activation and internalization of factor X and Merocyanine 540 staining. The infection does not result in an increase in PAI-1 and u-PA secretion, but it brings about a procoagulant response, which is relatively rapid compared to the tissue factor mediated response induced by inflammatory mediators. The time course and the coagulation factor dependency suggest a facilitated interaction of coagulation factors on the surface of infected cells. Chromogenic activity measurements after the addition of purified factor X and electron microscopic examination of the cells after addition of colloidal gold-factor X conjugates both point to an internalization of factor X and/or Xa after interaction with the endothelial cell surface. Merocyanine 540 staining suggests that CMV infection leads to membrane perturbations. 相似文献
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M J Busby M F Bellantoni J D Tobin D C Muller S D Kafonek M R Blackman R Andres 《Journal of the American Geriatrics Society》1992,40(5):497-502
OBJECTIVE: To determine the separate and interactive effects of age, phase of the menstrual cycle, menopausal hormone status, body fat mass, and regional fat distribution on glucose tolerance in healthy women. DESIGN: Retrospective study. SETTING: The Baltimore Longitudinal Study of Aging. PATIENTS: Two hundred sixty healthy women aged 22-89 years. MEASUREMENTS: Plasma levels of estradiol and progesterone, body mass index (BMI), waist-to-hip ratio (WHR), and plasma glucose values in the fasting state (FPG) as well as 120 minutes after 40 gm/m2 of oral glucose (G120) were measured for each participant. RESULTS: We found a progressive decline in oral glucose tolerance of 0.4 mM (6.7 mg/dL)/decade at G120) in women from early to late adult years, with no relationship to phase of the menstrual cycle and no abrupt change associated with the menopause. Multiple regression analysis revealed significant, independent effects of BMI and WHR on FPG and G120. The influence of age (P less than 0.01) on G120 was stronger than that of the BMI or WHR (P less than 0.05). There was no significant relationship between the levels of endogenous sex hormones and glucose tolerance after adjustments for age, BMI, and WHR. However, women taking oral contraceptives, but not those receiving postmenopausal replacement therapy, did exhibit mildly elevated G120 values. CONCLUSIONS: Age per se, and to a lesser extent BMI and WHR, but not levels of endogenous sex steroids, contribute to the physiological decline in glucose tolerance in older women. 相似文献
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