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41.
婴幼儿从出生开始正常呼吸道微生物就无时不刻地进行着演替,最终呼吸系统微生物形成动态平衡。婴幼儿时期是呼吸道微生物群演替的重要时期,也是免疫发育的关键时期,容易受外界因素的影响,这些影响因素包括分娩方式、喂养方式、抗生素、季节、疫苗接种等。研究表明婴幼儿时期的呼吸道微生物的组成和发育会影响微生物群的稳定性,从而影响呼吸道感染和过敏性疾病的发生。现对婴幼儿呼吸道微生物群演替及其影响因素,如分娩方式、喂养方式、抗生素使用、季节、疫苗接种等进行综述。  相似文献   
42.
This study analyses the relationship between consanguinity, fertility and child mortality in a rural population of two moroccan High-Atlas valleys. Among this very endogamous population, we have reconstituted, by inquiries, for each family, the totality of its reproductive life as well as the genealogic relationships that exist between the spouses on several generations. The analysis carried out on the group of families with women who are over 40 years old (438 families) has shown that the population was very strong related (28% of marriages are consanguineaous). A positive association between levels of fertility, infant mortality and consanguinity was observed.  相似文献   
43.
The social behaviour of a group of eight moustached tamarins,Saguinus mystax, (five males, three females) was studied on Padre Isla in northeastern Peru. About 60% of all allogrooming was done by the two adult males in the group, and about 11% by a young adult female. All other group members groomed very little. The adult breeding female received more grooming than any other group member. After the death of the adult female (preyed upon by an anaconda) the amount of active allogrooming remained constant for all group members except for the young adult female, who increased her contribution to about 30%. Her preferred grooming partner was the subadult female, which generally screamed when being groomed by the young adult female and terminated grooming by going away. This kind of grooming relation is termed “forced grooming” and is interpreted as a possible social control mechanism. The young adult female groomed the adult males more often after the death of the adult female than before. This might have had the function of strengthening the social bond with the adult males and in obtaining the breeding position in the group. After the death of the adult female, the vulva of the young adult female grew to full adult size. Agonistic behaviour was less frequent than allogrooming. Most aggressive interactions (50%) originated from the subadult male of the group. The young adult female was the target of most of these aggressions. Extremely little aggression occurred between the three females. The young adult female was the only individual who tried to emigrate from the group during the study period. Her attempt to join a neighbour group failed due to rejection by all four members of this group. All group members participated in carrying an infant, but the adult males and the young adult female carried most frequently. Contribution to infant carrying varied with the infant's age.  相似文献   
44.
目的:研究更昔洛韦联合大剂量丙种球蛋白治疗婴儿巨细胞病毒性(CMV)肝炎的临床疗效,为婴儿CMV肝炎的抗菌治疗提供理论依据。方法:选取我院自2009年7月至2016年1月收治的103例CMV肝炎婴儿,根据随机数字表法分为治疗组58例,对照组45例。两组患儿均常规给予退黄、保肝药物治疗,对照组在此基础上给予更昔洛韦治疗,治疗组给予大剂量丙种球蛋白联合更昔洛韦治疗。对比观察两组患儿治疗后黄疸消退情况、肝功能变化、血CMV-IgM和尿CMV-DNA转阴情况、肝和脾B超变化、治疗效果及不良反应情况。结果:治疗组患儿黄疸消退时间、血CMV-IgM和尿CMV-DNA转阴时间均短于对照组(P0.05);治疗组肝功能指标包括总胆红素(TBIL)、直接胆红素(DBIL)、丙氨酸氨基转移酶(ALT)、γ-谷氨酰转肽酶(GGT)水平均较对照组和治疗前降低(P0.05);治疗后两组肝、脾明显减小,且治疗组减小更显著,差异有统计学意义(P0.05);治疗组中血CMV-IgM转阴率、尿CMV-DNA转阴率、治疗总有效率均高于对照组(P0.05);治疗组不良反应发生率低于对照组(P0.05)。结论:更昔洛韦联合大剂量丙种球蛋白治疗婴儿CMV肝炎临床效果良好,可以有效缓解黄疸症状,恢复肝脏功能,肝、脾回缩明显,不良反应少,值得推广。  相似文献   
45.
Imitation of facial gestures by an infant chimpanzee   总被引:2,自引:0,他引:2  
A nursery-reared infant chimpanzee (Pan troglodytes) was tested for the ability to imitate human facial gestures, following the procedure ofMeltzoff andMoore (1977). The subject was observed between 5 to 15 weeks of ages. The results showed that the subject could imitate tongue protrusion in the age of 5–10 weeks and mouth opening between the ages of 5–11 weeks. However, from 12 to 15 weeks, the infant did not imitate the facial gestures. The present study clearly demonstrated that the infant chimpanzee could imitate human facial gestures in a particular period.  相似文献   
46.
少数民族新生儿及婴幼儿中人轮状病毒分子流行病学研究   总被引:1,自引:0,他引:1  
用聚丙烯酰胺凝胶电泳技术,对内蒙古自治区三个不同地理位置的少数民族自治旗及一个城市汉族对照区秋冬季采集的新生儿胎便及婴幼儿急性腹泻便进行轮状病毒RNA基因组特点分析。共检测胎便标本146份,腹泻便标中116份。结果表明:几个少数民族地区流行的轮状病毒均以A组第Ⅱ业组为士,并在一个地区有多种差异电泳型存在。新生儿胎便中可检出轮状病毒并显示了特征性A组轮状病毒RNA基因型。胎便小轮状病毒检出率高的地区,腹泻便检出率也相应高,轮状病毒的检出率与民族、地理位置尤明显关系,而与当地的卫生条件及地形有关。阳性标本使用A组单克隆抗体酶标免疫试剂进一步证实。  相似文献   
47.
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   
48.
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   
49.
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   
50.
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   
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