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1.
Colin W. BINNS Dawn GILCHRIST Beth WOODS Michael GRACEY Jane SCOTT Hannah SMITH 《Nutrition & Dietetics》2006,63(1):8-14
Objective: To document the breastfeeding practices of Aboriginal mothers delivering in Perth. Design and methods: A cohort of mothers was followed from the time of delivery for six months to obtain details of infant feeding practices. Subjects: A total of 455 mothers delivered during the study period and were asked to participate. A total of 425 mothers completed the initial questionnaire. Setting: The study was undertaken in six public hospitals in Perth, Western Australia. Data analyses: The data were analysed using spss . Breastfeeding duration was calculated using Kaplan–Meier survival analysis. Main outcome measures: Breastfeeding initiation and duration. Results: The mean age of the Aboriginal mothers was 21.8 years (range 14–39 years, SD 5.32) and the average gestational age was 38.3 weeks. Almost 50% of the mothers in the study delivered by Caesarean section. At discharge from hospital 89.4% (CI 86.6–92.1) of mothers were breastfeeding, declining to 58.8% (CI 53.5–64.1) at six months. When compared with non‐Aboriginal mothers, the Aboriginal breastfeeding rates were higher than the non‐Aboriginal average breastfeeding rates, but lower than the highest socioeconomic group. Conclusions: The breastfeeding rates of Aboriginal mothers are higher than for other Australians. This is despite the low maternal age and level of education and the high rates of low‐birth‐weight infants and Caesarean section among this population. The World Health Organization recommendation for infant feeding is exclusive breastfeeding until six months, but less than one‐third of Aboriginal mothers achieved this recommendation. 相似文献
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We used molecular modeling to examine the binding of 1, 2-dioctanoyl-sn-glycero-3-phosphocholine (a lecithin), 1-octanoyl-sn-glycero-3-phosphocholine (a lysolecithin) and their tetrahedral intermediates in the catalytic site of phospholipase A2 (PLA2). We performed energy minimization on each complex, computed the binding energy, determined the relative binding energy among the complexes and calculated the difference in inter- and intramolecular energies of the components in the complexes. We found that the calculated orientation of the sn-1 ester bond of lysolecithin in the active site is similar to that of the sn-2 ester bond in lecithin, thus permitting PLA2 to hydrolyze lysolecithin using the same mechanism as it uses to hydrolyze lecithin. On the other hand, the binding of lecithin is energetically more favorable by 4.5 kcal/mol than the binding of lysolecithin to the enzyme, and the binding of the lecithin tetrahedral intermediate is also energetically more favorable by 19.7 kcal/mol than the binding of the lysolecithin tetrahedral intermediate to the enzyme, which explains why lecithin is a better substrate than lysolecithin in the catalytic site. These results indicate that the activation energy for the hydrolysis of lysolecithin is higher than that for lecithin, consistent with the observed slower rate for the hydrolysis of lysolecithin. 相似文献
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A national sample of 1500 mothers of 1-year-old children received a postal questionnaire concerned with the sleeping patterns of their children. The response rate was 69%. Seventeen per cent of mothers reported that their 1-year-old presented a moderate or severe sleep problem and 26% said their child woke at night on at least five nights a week. While these two measures correlated, 10% of those who reported their infant woke on at least five nights a week did not consider this to be a problem. Neither sex of infant, social class, method of infant feeding or numbers of house moves were associated with sleep problems. The pattern of results strongly suggest an association between night waking and other sleeping difficulties and stress for mothers. This was indicated by the association we found with complaints about housing, overcrowding, more negative attitudes toward motherhood, lower assessments of maternal well-being, lack of practical support from partners, the use of more negative adjectives to describe their baby and more frequent feelings of being dominated by their baby. While these associations may be explained by the stresses of living with a night-waking baby, it is also likely that a mother who is feeling somewhat depressed and negative toward her baby is more likely to see night waking as significant and as a problem. There were class differences in how parents coped with a shortage of space. Middle-class parents were more likely to put a baby in with a sibling while working class parents more often had the baby in their own room. Middle-class parents were more likely to leave a night-waking baby to cry. 相似文献
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THOMAS M. JUNG MD PhD RAJ P. TERKONDA MD STEPHEN J. HAINES MD SCOTT STROME MD LAWRENCE J. MARENTETTE MD From the 《Otolaryngology--head and neck surgery》1997,116(6):642-646
The classic approach to anterior skull base lesions uses bifrontal craniotomies together with lateral rhinotomies. This approach requires frontal lobe retraction and is associated with postoperative anosmia and the development of frontal lobe encephalomalacia. The transglabellar/subcranial approach permits removal of anterior skull base lesions without frontal lobe retraction and avoids facial scars. No studies to date, however, have directly compared the two approaches in terms of patient morbidity. The present retrospective study compares the two approaches when used for the removal of anterior skull base lesions in terms of estimated blood loss, number of transfusions, number of days in the hospital and intensive care unit, and postoperative complications. Twenty patients with anterior skull base lesions were examined. The classic approach was used on 10, and the transglabellar/subcranial route was used on 10. When compared with the classic approach, the transglabellar/subcranial approach resulted in a lower estimated blood loss and subsequent transfusion rate, fewer days in the hospital and intensive care unit, and lower numbers and less severe types of complications. Furthermore, visualization of the tumors before resection with the transglabellar/subcranial approach allowed preservation of olfaction in virtually all of these patients. Although this study represents a small sample population, the results are sufficiently impressive to favor the transglabellar/subcranial approach for the removal of a variety of anterior skull base lesions. (Otolaryngol Head Neck Surg 1997;116:642-6.) 相似文献
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