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31.
Attention mediates the acquisition and encoding of information about the world and is central to motor action. Heart rate deceleration and behavioral inhibition are sensitive indices of the attentional process, but it is unknown whether these indices are valid in the context of overt action. The current study investigated the relationship between visual attention, action, and heart rate during reaching in 7(1/2)-month-old infants. We found that infants showed prolonged looking and large heart rate decelerations on reaching and looking trials. We conclude that overt action itself does not prevent the autonomic and behavioral changes that are also seen in attention to simple visual displays and that attention is maintained throughout the act of reaching. 相似文献
32.
双歧杆菌对早产儿食道pH值的影响及临床意义 总被引:2,自引:0,他引:2
目的为探讨双歧杆菌对早产儿食道pH值的影响,及其对早产儿易发生的消化道疾病的防治意义。方法我们采用便携式24hpH值自动记录仪,对61例早产儿进行了食道pH值的动态监测。结果口服双歧杆菌活菌制剂组的30例早产儿,食道pH值明显高于未服药的对照组,t=2.4093,P<0.05。总pH值<4的时间占总观察时间的百分比显著小于对照组。并且治疗组发生消化道疾患的人数也较对照组少。结论早产儿口服双歧杆菌活菌制剂可以减少胃食道反流等消化道疾病的发生。 相似文献
33.
Background: The sudden infant death syndrome (SIDS) is still the main cause of postneonatal infant death. However, the causes and mechanisms of SIDS have never been completely elucidated. Catecholamines, via α2-adrenergic receptor (α2-AR) interactions, are known to influence brainstem autonomic and respiratory activity. Aims: To examine the catecholaminergic system abnormalities in SIDS victims, we investigated the alterations of α2-AR subtypes. Subjects and methods: We examined the developmental changes of α2-AR subtypes in the brainstem, especially in cardiorespiratory nuclei, in 21 SIDS victims and 17 age-matched controls by means of immunohistochemical methods. For statistical analysis, the χ2-test or Fisher’s exact probability test was performed. Results: There was a significant decrease in α2A-AR immunoreactivity in the solitary nucleus and ventrolateral medulla (VLM) in the medulla oblongata in SIDS victims compared with in control cases, but there were no significant differences of the α2B and α2C-AR immunoreactivity in the brainstem between SIDS victims and controls. Conclusion: α2A-AR immunoreactivity was selectively decreased in the solitary nucleus and VLM in the medulla oblongata in SIDS victims, so there was no possibility that it was secondary to chronic hypoxia or repeated ischemia. It may be related to some impairment of the cardiorespiratory neuronal system. Therefore, SIDS victims may be vulnerable to asphyxia, hypoxia, and/or hypercapnia, and fail to exhibit brainstem responses. 相似文献
34.
Three monkeys with travel vision and 5 controls were observed with their mothers during the first 6 months of age and then for another 3 months after they had been placed in social isolation. In the home cage, the experimental animals did not differ from controls except that two held a hand before their eyes in a stereotyped fashion not previously reported for animals. In an unfamiliar environment the blind animals did not look at an observer, threatened less than normal, and were awkward in moving around. Animals who held hands before eyes tended to approach a flickering visual stimulus. 相似文献
35.
36.
We developed a sensitive sandwich-type ELISA for measuring low levels of cow's milk (CM) β-lactoglobulin. Purified anti-β-lactoglobulin was used as coating antibody and also as second antibody conjugated with alkaline phosphatase. Polyethylene glycol 6000 was added to the incubation buffers to improve sensitivity. The detection limit of the assay was 0.002 μg/l, which is much better than sensitivities reported for other β-lactoglobulin assays. The sensitivity was not impaired by the presence of other CM proteins. The recovery from breast milk was 93% and from the diluting buffer 127%. The coefficient of variation within day was 5–15% and between days 10%. One hour after oral intake of milk, P-lactoglobulin could be detected in the breast milk of three mothers at concentrations of about 1–2 μg/l. Widely different concentrations of β-lactoglobulin were measured in two protein hydrolysates based on CM whey and casein proteins; the observed concentrations were 200 and 0.0056 μg P-lactoglobulinμ/g dry weight, respectively. 相似文献
37.
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
38.
The effects of separation and reunion on the behavior of mother and infant squirrel monkeys 总被引:1,自引:0,他引:1
J Kaplan 《Developmental psychobiology》1970,3(1):43-52
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
39.
Colon AJ Vredeveld JW Blaauw G Slooff AC Richards R 《Clinical anatomy (New York, N.Y.)》2003,16(1):25-29
In the pre-operative screening of infants with obstetric brachial palsy (OBP), the results of routine electromyography are often overly optimistic when compared to the peri-operative findings. This prompted us to include investigation of the sensory innervation of these infants using the N20 (the first cortical response to a peripheral stimulation) of the somatosensory evoked potentials (SSEP). Three to seven months after birth, SSEP were recorded at the skull after stimulation of the thumb and middle finger in infants with obstetric rupture of the upper trunk or avulsion of roots C5, C6, or C7, and in whom no clinical improvement of motor function was observed in the biceps brachii and deltoid muscles. In most infants, a normal N20 could be evoked, indicating the existence of peripheral sensory pathways. From the thumb, these sensory pathways would necessarily bypass the upper trunk and dorsal roots of spinal nerves C5 and C6, and from the middle finger bypass the middle trunk and dorsal root C7, before extending into the dorsal column and projecting toward the thalamus and cerebral cortex. These data suggest that in infancy the segmental sensory innervation of the hand is more diverse than is described in most textbooks. 相似文献
40.
Franka Neumer Orenci Urraca Joaquin Alonso Jesús Palencia Vicente Varea Stephan Theis Maria Rodriguez-Palmero Jos Antonio Moreno-Muoz Francisco Guarner Gigi Veereman Yvan Vandenplas Cristina Campoy 《Nutrients》2021,13(4)
The present study aims to evaluate the effects of an infant formula supplemented with a mixture of prebiotic short and long chain inulin-type oligosaccharides on health outcomes, safety and tolerance, as well as on fecal microbiota composition during the first year of life. In a prospective, multicenter, randomized, double-blind study, n = 160 healthy term infants under 4 months of age were randomized to receive either an infant formula enriched with 0.8 g/dL of Orafti®Synergy1 or an unsupplemented control formula until the age of 12 months. Growth, fever (>38 °C) and infections were regularly followed up by a pediatrician. Digestive symptoms, stool consistency as well as crying and sleeping patterns were recorded during one week each study month. Fecal microbiota and immunological biomarkers were determined from a subgroup of infants after 2, 6 and 12 months of life. The intention to treat (ITT) population consisted of n = 149 infants. Both formulae were well tolerated. Mean duration of infections was significantly lower in the prebiotic fed infants (p < 0.05). The prebiotic group showed higher Bifidobacterium counts at month 6 (p = 0.006), and higher proportions of Bifidobacterium in relation to total bacteria at month 2 and 6 (p = 0.042 and p = 0.013, respectively). Stools of infants receiving the prebiotic formula were softer (p < 0.05). Orafti®Synergy1 tended to beneficially impact total daily amount of crying (p = 0.0594). Supplementation with inulin-type prebiotic oligosaccharides during the first year of life beneficially modulates the infant gut microbiota towards higher Bifidobacterium levels at the first 6 months of life, and is associated with reduced duration of infections. 相似文献