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921.
It has been reported that 83%–87% of full-term infants regularly sleep through the night (from midnight to 5 a.m.) by 6 months of age, but there is little information about the sleep patterns of premature infants. The purpose of the current study was to identify maternal perceptions of the sleep patterns of premature infants. Parents of 32 premature infants with birth weight below 1,750 gm and of 13 full-term infants completed a 24-hour sleep record in 30-minute epochs for 1 week at 7 months of chronological (term) or corrected age (premature). Mean birth weight of premature infants was 1,278 ± 340 gm, with a gestational age of 30.4 ± 2.7 weeks. The daily total sleep time, longest sleep segment, frequency of sleep-wake transitions, and percentage of night sleep (8 p.m.–8 a.m.), averaged from the 1-week sleep record and number of night wakenings per week, were used as indicators of sleep patterns. The longest reported sleep segments of premature infants were significantly shorter than those of full-term infants (8.2 ± 2 hours versus 9.6 ± 1 hour, p < 0.01) and the number of night wakenings per week was significantly greater (3.13 ± 3 versus 0.54 ± 7, p < 0.005). Total reported sleep time, percentage of night sleep, and sleep-wake transitions did not differ significantly between premature and full-term infants. However, analysis of feeding events revealed that premature infants received significantly more feedings between midnight and 5 a.m. (M = 0.31 + 3 versus M = 0.06 + 1, p < 0.001). We conclude that sleep pattern diaries kept by parents indicate that premature infants have developed a diurnal sleep rhythm by 7 months corrected age, but they still have shorter sleep segments and they awaken more during the night than term infants.  相似文献   
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Pitirim Sorokin is known as both a pioneer and outcast in the history of American sociology. A Russian emigré with a bruising and combative intellectual style, he was increasingly treated as a pariah by the sociological community. Yet in 1963 he won the presidency of the American Sociological Association by a landslide. Otis Dudley Duncan and the Committee of Eight implemented on his behalf the first successful write-in campaign in the history of the Association. This event put Sorokin in the presidency and significantly changed the electoral processes and politics of the Association. How this came to be so constitutes the focus of this paper.  相似文献   
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Adam [1976; Lehman and Adams, 1977] suggested that a resident rat makes an olfactory comparison of cage odor and other rat odor prior to attacking an unfamiliar conspecific intruder. The findings of the present study are consistent with the notion that rats discriminate between familiar and unfamiliar putative urinary odorants Adult male albino rats were tested for preferences between areas treated with familiar urine (11 hours pretest exposure), unfamiliar urine (no pretest exposure), and untreated areas. Subjects (N = 12) preferred areas treated with familiar urine over ones treated with unfamiliar urine (p < 0.05). Also, they (N = 12 per preference-test group) preferred areas treated with either urine over untreated ones (familiar versus clean, p < 0.01; unfamiliar versus clean, p < 0.05).  相似文献   
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Applied Research in Quality of Life - Cars represent a valuable real asset that most individuals use on a daily basis. Although cars are a form of material prosperity like income and other forms of...  相似文献   
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