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1.
Brief observations of mother-stimulated infant vocalizationwere perform ed during pediatric clinic visits on 4- to 6-month-oldinfants to determine whether mothers with positive attitudestoward the pregnancy and/or the in fant would have infants whovocalized more during clinic visits. Mothers with more positiveattitudes toward the pregnancy, assessed prenatally, had infantswho showed significantly more vocalization during clinic visitsat 5 months, 6 months, and the combination of 5 and 6 months.Mothers with more positive attitudes toward the infant had infantswho showed signcantly more vocalization at 4 months and thecombination of observations at 4 months and 6 months. Resultssuggest that brief observations of vocalization during clinicvisits may be useful as a rough index of the quality of themother-child interaction.  相似文献   
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Mother and infant squirrel monkeys that lived together in a socially restricted environment were separated for a period of seven days after the infants had become relatively independent, and were then reunited. Behavioral observations before, during, and after separation indicated that (1) female infants became independent of their mothers earlier than males, (2) neither mothers nor infants were severely affected by separation, and (3) an increase in attachment occurred following reunion only when the mother had a limited history of maternal experience. These results suggest that (1) certain characteristics in the maternal behavior of the squirrel monkey facilitate readjustment in mothers and infants following maternal separation, (2) maternal experience can influence the mother-infant relationship following a period of separation, and (3) the independence of infants from their mothers may be a function of both sex and species.  相似文献   
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Abstract The effects of preterm birth and the perinatal infant health condition on mother-infant interactions were analysed in 278 mother-infant pairs, divided into four groups according to infants' gestational age at birth: group 1. 23–31 weeks; group 2,32–36 weeks; group 3, 37–42 weeks; and group 4, a control group of healthy full-term infants. The methodological approach was based on observation of the pairs at 2,4 and 6 months of infants" corrected age (± 1 week) during undressing of the infant and face-to-face interaction. It was found that mother-infant pairs with preterm infants (groups 1 and 2) did not differ in interactional variables from those of the control group. On the other hand, the birth of a full-term infant in need of neonatal intensive care (group 3) affected maternal and infant interactive behaviour. Additionally, infants from group 3 did not show stability in their interactive behaviour between any ages of measurement. This result suggests that interactive behaviour of full-term infants in need of neonatal intensive care are rather unpredictable during their first 6 months of life, which might have contributed to the less optimal interactive pattern observed for their mothers compared with mothers of the control group.  相似文献   
4.
目的:探讨HBV携带产妇血清、乳汁HBV-DNA载量的不同状况与实施母乳喂养安全性的关系.方法:检测产妇血清、乳汁及婴儿血标本HBV-DNA载量.对母乳和人工两种喂养方式婴儿做追踪观察.结果:HBsAg、HBeAg双阳性产妇的血清、乳汁HBV-DNA阳性率分别为100%、49.45%(P<0.01).两种喂养方式婴儿的HBV感染率为15.63%和13.56%,无显著性差异;婴儿抗-HBs检测,母乳组抗体几何平均滴度(GMT)明显高于人工喂养组;结论:HBV携带产妇乳汁HBV-DNA阳性率和病毒载量明显低于血清.母乳喂养不影响母婴传播阻断效果,且有助于提高婴儿抗-HBs的GMT水平.  相似文献   
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目的探讨分阶段联合吸奶法对母婴分离产妇泌乳的影响。方法将72例母婴分离产妇随机分为对照组和干预组各36例,对照组实施常规护理,干预组在常规护理的基础上由护理人员指导产妇在不同泌乳阶段联合吸奶器、手挤奶及乳房挤压、按摩以维持乳汁分泌。结果干预组产后泌乳始动时间分布显著优于对照组(P0.01),产后第1、2、3、4、5天泌乳量显著多于对照组(均P0.01)。结论分阶段联合吸奶法使母婴分离产妇泌乳始动时间提前,乳汁产量增加,其对改善后续母乳喂养的作用尚需进一步验证。  相似文献   
10.
《Vaccine》2018,36(50):7700-7707
To date, inducing the production of broadly neutralizing antibodies (bnAbs) against HIV-1 in humans has been unsuccessful. Several studies have explored the coevolution of HIV-1 and neutralizing antibodies (nAbs), but little is known about what affects the lack of bnAbs after long-term infection. A better understanding of the coevolution of the virus and nAbs in cases involving no bnAb production will help in the design of an effective HIV-1 vaccine. An individual with acute CRF01_AE HIV-1 infection who lacked bnAbs at just over 2 years post-infection (p.i.) was identified from a cohort of HIV negative men who have sex with men. The coevolution of the viral envelope gene and nAbs was studied over 741 days p.i. Strain-specific antibodies (ss-Abs) to the transmitted/founder (T/F) virus developed within 54 days p.i., but plasma collected at subsequent time points could not neutralize synchronous viruses until 557 days p.i., when the plasma acquired low-level synchronous but not heterologous neutralizing activity. The V4 region of envelope gene mutated firstly and continually evolve up to 2 years p.i. Multiple variations in the V4 region, including substitutions, deletions and glycosylation mutations, were driven by ss-Abs and mediated immune escape partially by impacting the binding of nAbs to the virus. The remarkable variations in the V4 region mediated immune escape from ss-Abs and contributed to the affinity maturation of ss-Abs against the T/F virus but may not promote the development of bnAbs. Thus, the V4 region might not be a good target for an HIV-1 vaccine.  相似文献   
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