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81.
The dentate gyrus is one of only two regions of the mammalian brain where substantial neurogenesis occurs postnatally. However, detailed quantitative information about the postnatal structural maturation of the primate dentate gyrus is meager. We performed design‐based, stereological studies of neuron number and size, and volume of the dentate gyrus layers in rhesus macaque monkeys (Macaca mulatta) of different postnatal ages. We found that about 40% of the total number of granule cells observed in mature 5–10‐year‐old macaque monkeys are added to the granule cell layer postnatally; 25% of these neurons are added within the first three postnatal months. Accordingly, cell proliferation and neurogenesis within the dentate gyrus peak within the first 3 months after birth and remain at an intermediate level between 3 months and at least 1 year of age. Although granule cell bodies undergo their largest increase in size during the first year of life, cell size and the volume of the three layers of the dentate gyrus (i.e. the molecular, granule cell and polymorphic layers) continue to increase beyond 1 year of age. Moreover, the different layers of the dentate gyrus exhibit distinct volumetric changes during postnatal development. Finally, we observe significant levels of cell proliferation, neurogenesis and cell death in the context of an overall stable number of granule cells in mature 5–10‐year‐old monkeys. These data identify an extended developmental period during which neurogenesis might be modulated to significantly impact the structure and function of the dentate gyrus in adulthood.  相似文献   
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益智调神方药提高多动症患儿学习记忆功能的实验研究   总被引:2,自引:0,他引:2  
学习困难是儿童多动症的主要症状之一,用益智调神方药治疗能使患儿学习成绩提高。动物实验证明该药能提高正常小鼠的学习记忆功能;对记忆障碍模型小鼠的学习记忆功能也有不同程度改善。  相似文献   
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Colostrum protects the newborn from intestinal infection by its content of secretory immunoglobulin A and other immediately acting factors. It may also induce maturation of the child's gastrointestinal immune defences, thus contributing to the protection against diarrhoeal disease later in infancy. To test this hypothesis, a case–control study on breast feeding and diarrhoea was carried out in a periurban community in Guinea–Bissau. The child's age at the start of breast feeding was ascertained soon after birth ( n = 279). Subsequent cases of acute diarrhoea ( n = 66) were identified at 3–monthly examinations, and four concurrent controls were randomly selected among attendants. Three separate estimates of association showed that the cases tended to have started breast feeding later after birth than the diarrhoea–free controls, but no single test was statistically significant. Early breast feeding might have consequences for diarrhoeal morbidity after the neonatal period.  相似文献   
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ABSTRACT. Serum levels of 8 steroids and urinary Cortisol excretion were determined in 10 infants before and during corticotropin therapy for infantile spasms. High serum dehydroepiandrosterone-androstenedione concentration ratio distinguished the 6 infants with good therapeutic response from the 4 with poor response ( p =0.001). No such distinction was obtained directly by any of the serum steroid levels, 24-hour urinary Cortisol, or serum pregnenolone-proges-terone concentration ratio. This suggests that the therapeutic effect of corticotropin may be mediated by steroid factors other than Cortisol. Inhibition of the 3 β-hydroxysteroid dehydrogenase system in zona reticularis might be beneficial during the corticotropin therapy.  相似文献   
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PURPOSE: To investigate ictal muscular phenomena characterizing symptomatic infantile spasms (ISs) and their relation to ictal EEG. METHODS: Four children with severe encephalopathy, neurologic impairment, and refractory ISs related to different dysplastic lesions, underwent videopolygraphic recordings collecting surface electromyogram (EMG) activity from several cranial and limb muscles to evaluate the pattern of muscular recruitment, duration, and side-to-side asymmetry of ISs. Acquired data were stored for off-line analysis by a computerized polygraphic system. RESULTS: Spasms were characterized by a complex pattern of muscular activation. A constant or rostrocaudal propagation pattern was lacking in all patients. Intervals between the onset of EMG activity in different muscles in each spasm were very long: 相似文献   
88.
Possible associations between autism and specific medical disorders have been suggested, and this could be of relevance in the clinical examination and treatment of patients and may help to identify factors involved in the etiology or pathophysiology of autism. Two population-based Danish registers were used to investigate the occurrence of medical disorders in patients with autism according to ICD-8 and in a matched control sample. A total of 29 of the 244 patients (11.9%) diagnosed with autism had one or more medical disorders. In contrast to previous studies, we did not find an increased occurrence of almost any medical disorders. A highly significant increased frequency of congenital malformations was found, which may indicate abnormalities in embryogenesis in the etiology of autism.  相似文献   
89.
Prenatal factors have been implicated in childhood eczema, but the relationship between maternal cytokine production during pregnancy and infant eczema is unknown. Non-selected women in their third trimester were enrolled in the Tucson Infant Immune Study. Data from three sources were used to define MD-eczema: parent-completed illness questionnaires at age 2, 3, 4, 6 and 9 months regarding physician-seen eczema, parent-completed questionnaires at 12 months regarding physician-diagnosed eczema, and medical record reviews. Blood samples were taken from mothers during their third trimester and from the umbilical cord at birth. Maternal peripheral blood mononuclear cells and cord blood mononuclear cells were stimulated with ConA/PMA, and supernatants were assayed for IFN-gamma and IL-4, -5, -10, and -13. Of 364 children, 28% were seen by a physician for eczema by 1 yr of age. After adjustment for potential confounders using logistic regression, the odds for development of eczema in infancy were significantly higher when mothers had active eczema in pregnancy (OR, 2.46, CI 1.0-5.8, p <0.042) and when mothers were in the highest tertile of serum IgE production (OR 2.28, CI 1.2-4.4, p <0.013). Colds in the third trimester were associated with lower odds of eczema (OR 0.32, CI 0.16-0.63, p <0.001). Our findings from this cohort study suggest that in utero factors, including maternal IgE, colds, and eczema, may influence the risk of infant eczema.  相似文献   
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穴位注射氟哌啶预防输卵管结扎术中牵拉反应200例   总被引:1,自引:0,他引:1       下载免费PDF全文
穴位注射氟哌啶预防输卵管结扎术中牵拉反应200例王海波,李萍我们在局部麻醉的基础上,结合内关穴注射氟哌陡,以预防输卵管结扎术中牵拉反应及术中术后患者的恶心、呕吐症状,取得了满意效果。现报告如下。临床资料1995年2月~1995年12月,对在我科门诊准...  相似文献   
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