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排序方式: 共有236条查询结果,搜索用时 15 毫秒
51.
Xiaomei Cong Wanli Xu Rachael Romisher Samantha Poveda Shaina Forte Angela Starkweather Wendy A. Henderson 《The Yale journal of biology and medicine》2016,89(3):299-308
The development of the neonatal gut microbiome is influenced by multiple factors, such as delivery mode, feeding, medication use, hospital environment, early life stress, and genetics. The dysbiosis of gut microbiota persists during infancy, especially in high-risk preterm infants who experience lengthy stays in the Neonatal intensive care unit (NICU). Infant microbiome evolutionary trajectory is essentially parallel with the host (infant) neurodevelopmental process and growth. The role of the gut microbiome, the brain-gut signaling system, and its interaction with the host genetics have been shown to be related to both short and long term infant health and bio-behavioral development. The investigation of potential dysbiosis patterns in early childhood is still lacking and few studies have addressed this host-microbiome co-developmental process. Further research spanning a variety of fields of study is needed to focus on the mechanisms of brain-gut-microbiota signaling system and the dynamic host-microbial interaction in the regulation of health, stress and development in human newborns. 相似文献
52.
Mauvis A. Gore 《Primates; journal of primatology》1986,27(2):205-214
Theory suggests that it is in the interest of an infant to garner more care than its mother is selected to provide and that
a rival sibling would curtail care from the mother. Thus delayed conception in the mother would be of advantage to the infant.
One method of achieving this result would be to interfere with the mother's potential matings. To test this theory, the conflict
between mothers and their infants in relation to maximizing inclusive fitness has been studied inMacaca fascicularis and infant interference has been observed. Focal animal samples were taken on 8 mothers and their 13 infants. Interactions
analyzed were those between the mother and (1) an adult male, (2) her infant, (3) an adult female, (4) her infant and an adult
male, (5) her infant and an adult female. Only explicit behaviours were analyzed. The infant's interference was found to be
significantly related to its mother's mating, and this produced a deterring effect on the male. Infants did not interfere
with any female's matings other than those of their mother. The interference was related to the number of mother-male contacts.
In mothers that did subsequently conceive, infant interference at mating increased up to the mother's conception date and
decreased thereafter. By contrast to the infants direct method, mothers approached the conflict indirectly. There were significantly
more contacts and mounts with males in their infant's absence, they reacted negatively to their infant only when it had interfered,
they were more lenient in the presence of an adult female than with an adult male, and they avoided their infant's presence
at mother-male contacts. No significant sex bias in interference or the number of contacts with mother-male pairs has been
found. There are indications of a sibship pattern of interference. 相似文献
53.
The social relationships between the members of a family consisting of eight captive common marmosets (Callithrix jacchus) are here examined, as well as the participation of individual family members in infant carrying and defensive behaviour
against non-related intruders (adolescent males). Within the social relationships, a clear division of the family into three
subgroups (parents, adult offspring, non-adult offspring) could be determined, whereby the adult offspring, especially with
respect to the parents, occupy a peripheral position. In the types of cooperative behaviour examined here, substantial participation
in infant carrying could be observed in only four family members (parents, adult son, one subadult daughter), and in defence
against intruders in only two family members (adult son, one subadult daughter). Participation in infant carrying remained
stable throughout the study period. Conversely, individual changes in participation in defence against intruders could be
determined, dependent upon the presence of infants carried. The advantages and disadvantages of social substructuring observed
are discussed here, in particular the peripheral position of adult offspring, possible connections in individually varied
participation in cooperative behaviour, and possible regulative mechanisms. In view of past studies on cooperative behaviour
among marmosets, it is here presumed that pronounced individual differences result from a division of labour within the family
with respect to various aspects of cooperative behaviour. 相似文献
54.
S A Quandt 《American journal of physical anthropology》1987,73(4):515-523
Sources of variance in dietary intake data for infants in the fourth to sixth months of life were examined. Twenty-eight mothers of infants in the Special Supplemental Food Program for Women, Infants, and Children gave 24-hr recall information on their infants' diets on 4 random days over approximately 1 month. ANOVA found no day of the week or sequence effects on nutrient variation. Variance was partitioned into between- and within-subject (residual) components. Interindividual variation exceeded intraindividual variation for all nutrients except vitamin C. Variance ratios ranged from 0.3 to 1.3. Calculations of 95% confidence limits for group and individual mean intakes indicated that, whereas a single recall would estimate the group mean within 20% for most nutrients, five recalls would be necessary for the same accuracy in individual means. Magnitude and patterning of variance components differ substantially from those found in studies of adults, suggesting that infant data collection strategies should be tailored to the unique nature of the infant diet. 相似文献
55.
轮状病毒自上世纪70年代初发现至今,仍是婴幼儿病毒性腹泻最主要的病原体。每年约60万婴幼儿因轮状病毒感染导致严重脱水死亡。轮状病毒疫苗从上世纪90年代初开始研制,至今已有三种疫苗用于预防轮状病毒感染。这三种疫苗均为减毒活疫苗:其中包括单一血清型Rotarix、罗特威和重组5价疫苗RotaTeq。它们已在全球多国使用,有些国家已将其纳入免疫规划。疫苗的使用使人群轮状病毒感染下降,特别是死亡率明显减少。但也出现了一些问题,因此除了减毒活疫苗,也有一些实验室研究其他形式的疫苗,例如重组疫苗、灭活疫苗等。本文主要介绍轮状病毒疫苗的研究现状,为我国轮状病毒疫苗的研究、使用和推广提供一定理论依据。 相似文献
56.
目的:研究孕妇维生素D(25(OH)D)含量与新生儿湿疹的关系,为改善孕期维生素D缺乏,预防婴儿湿疹提供临床依据。方法:选取2013年9月-2013年11月在我院生产的孕妇及所生的新生儿,调查研究对象的基本情况。采集孕妇的静脉血进行25(OH)D含量测定,并诊断新生儿湿疹的发生情况。结果:孕妇25(OH)D含量的中位数是15.17 ng/m L,新生儿湿疹的发病率是26.1%。孕妇不同含量25(OH)D水平与孕中晚期补充复合维生素、服用奶制品、摄入鱼蛋类次数、每天晒太阳时间等有关(P0.05);孕妇25(OH)D含量20 ng/m L会增加子女6个月内患湿疹的风险(OR=3.19,95%;CI:1.54,4.21)。结论:孕妇25(OH)D含量缺乏会增加新生儿湿疹的发病率。 相似文献
57.
Irene Masci 《International Journal of Anthropology》2006,21(3-4):165-182
This article, part of a wider study on fertility dynamics in Kenya, attempts to synthetically reconstruct the evolution of
the Kenyan population structure over the past 60 years, following the development of population policies adopted by the Kenyan
government. It emphasizes the importance and the necessity of political participation in order to restrain the population
growth that, in a country such as Kenya, aggravates the existing deficiencies in the field of nutrition and hygiene. The article
also takes a brief look at the future prospects of Kenya. 相似文献
58.
Ariane Kemkes 《Human ecology: an interdisciplinary journal》2009,37(4):393-405
Based on the U.S. Federal Mortality Schedules from the years 1850–1880 infant deaths <1 year were investigated in order to
determine whether mortality attributed to “smothering” or “overlaying” followed known SIDS trajectories. By comparing a case
sample of 2,236 smothered/overlaid deaths with an age-, regionally and time-matched control sample of all-cause infant deaths
(N = 58,293), striking similarities with SIDS became apparent, which were not mimicked in the control sample. These epidemiological
traits included a disproportionate vulnerability during the second to fourth month of life (Poisson RR 12.94, p < 0.001), a remarkable birth and death seasonality, as well as pronounced racial disparities. The study could also corroborate
sex-specific discrepancies—such as differential impact of month of birth on age-at-death. Results of a Cox regression furthermore
indicate that age, sex, race and death season were significant predictors of mortality. This strongly supports the hypothesis
that these infant deaths represent empirical evidence of 19th century SIDS. 相似文献
59.
Yang Sun Dinghua Yi Yunya Wang Renhong Zheng Guocheng Sun Jing Wang Yang Liu Jun Ren Yuemin Wang Shumiao Zhang Chunhu Gu Jianming Pei 《Cytokine》2009,47(3):206-213
This study was designed to find the effects of age on circulating endothelial progenitor cells (EPCs) and their mobilization in infants and young children following surgical correction of congenital heart defects. In 60 consecutive infants and young children (1 month to 3 years old) undergoing repair of atrial/ventricular septal defect, the numbers of EPCs and plasma levels of IL-6, -8, -10, TNF-α, VEGF and G-CSF were determined preoperatively, at the end of cardiopulmonary bypass (CPB), as well as 6, 12, 24, 48, 72 and 96 h following surgery. Preoperative EPCs were reduced with increased age, similar to changes in plasma VEGF and G-CSF levels. Rapid mobilizations of EPCs and plasma VEGF, G-CSF were induced by cardiac surgery with CPB in all infants and young children, and the increased volumes of EPCs, VEGF and G-CSF decreased with age decreasing. The increased volumes of IL-6, -8, -10 and TNF-α were similar in different age groups. However, mobilization of EPCs, plasma VEGF and G-CSF were limited in infants <6 months old, which did not correlate with change in inflammatory IL activation. Preoperative EPCs and plasma levels of VEGF and G-CSF were reduced with increasing age in infants and young children. Although a significant increase in EPCs and release of cytochemokines were observed in infants undergoing CPB, the mobilization of EPCs of the infants <6 months old are limited. 相似文献
60.
注射Bestatin对幼年大鼠分辨学习的影响 总被引:3,自引:0,他引:3
以Spraque-Dawley大鼠为实验动物,从出生后第1天起,每日皮下分别注射氨基肽酶的抑制剂Bestatin(1mg/kg(b.w))以及钠络酮(2mg/kg(b.w)+Bestaing(1mg/kg(b.w)),对照组注射等量的生理盐水,连续注射14天,观察:16日龄幼鼠的吸乳迷津分辨学习(ADL),30日龄Y迷津明暗分辨学习(ADL),30日龄Y迷津明暗分辨学习(BDL)行为,45日龄幼鼠 相似文献