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21.
Stephanie Moriceau Tania L. Roth Terri Okotoghaide Regina M. Sullivan 《International journal of developmental neuroscience》2004,22(5-6):415-422
In many altricial species, fear responses such as freezing do not emerge until sometime later in development. In infant rats, fear to natural predator odors emerges around postnatal day (PN) 10 when infant rats begin walking. The behavioral emergence of fear is correlated with two physiological events: functional emergence of the amygdala and increasing corticosterone (CORT) levels. Here, we hypothesize that increasing corticosterone levels influence amygdala activity to permit the emergence of fear expression. We assessed the relationship between fear expression (immobility similar to freezing), amygdala function (c-fos) and the level of corticosterone in pups in response to presentation of novel male odor (predator), littermate odor and no odor. CORT levels were increased in PN8 pups (no fear, normally low CORT) by exogenous CORT (3 mg/kg) and decreased in PN12 pups (express fear, CORT levels higher) through adrenalectomy and CORT replacement. Results showed that PN8 expression of fear to a predator odor and basolateral/lateral amygdala activity could be prematurely evoked with exogenous CORT, while adrenalectomy in PN12 pups prevented both fear expression and amygdala activation. These results suggest that low neonatal CORT level serves to protect pups from responding to fear inducing stimuli and attenuate amygdala activation. This suggests that alteration of the neonatal CORT system by environmental insults such as alcohol, stress and illegal drugs, may also alter the neonatal fear system and its underlying neural control. 相似文献
22.
Liana Beni-Adani Naresh Biani Liat Ben-Sirah Shlomi Constantini 《Child's nervous system》2006,22(12):1543-1563
Background and objective The classification of hydrocephalus in newborns and in infants is different from the classification in adulthood. This difference
exists due to disparity in the source pathologies that produce the hydrocephalus, and the practical distinctions in prognosis
and treatment choices. The objective of this paper is to present the spectrum of obstructive-communicating hydrocephalus,
which is more complex in the pediatric group, and to propose the relevance of this particular classification to treatment
options.
Materials and methods The authors categorized infants with active hydrocephalus at time of presentation into the following four groups along the
spectrum of communicating vs obstructive HCP. Group 1: patients with a purely absorptive (communicating) HCP. In these patients,
tetraventricular dilatation is usually observed with occasional extraaxial fluid accumulation. An extracranial CSF diversion
(shunt) is the treatment of choice. Group 2: patients with an obstructive component together with a persistent absorptive
component. In these patients, a technically successful endoscopic procedure will not prevent progression of clinical symptoms
of HCP. An extracranial CSF diversion (shunt) should be the treatment of choice even though some of these patients are currently
treated by endoscopy. Group 3: patients with an obstructive component together with a temporary absorptive component. In these
patients, a technically successful ETV should be followed by temporary CSF drainage [via LP, continuous spinal drainage (CLD),
or ventriculostomy] with or without supplemental medical treatment (i.e., Diamox) for several days. Such temporary drainage
may decrease failure rate in this subgroup. Group 4: patients with a purely obstructive HCP. In these patients, an endoscopic
procedure (ETV) is the treatment of choice. According to this spectrum classification, the authors classify different entities
with representative cases and discuss relevancy to treatment options and prognosis.
Results The data suggest that obstructive hydrocephalus in the very young population may be rather a combination of obstructive and
absorptive problem. The outcome of the patient depends mainly not only on the basic pathology causing the hydrocephalus but
also on the treatment that is chosen and its complications. While bleeding and infection represent the major causes for communicating
hydrocephalus, patients with complex pathologies of congenital type and intra- or interventricular obstructions may reflect
obstructive hydrocephalus. Treatment of these patients may be successful by shuntless procedures if the absorptive problem
is not the major component. In transient absorptive hydrocephalus, temporary measures were effective in many cases leading
to successful procedures of ETV and/or posterior-fossa decompression in selected cases.
Conclusions Shuntless procedures are the dream of a pediatric neurosurgeon provided it solves the problem and does not imply unacceptable
risk. However, the benefit has to be evaluated years after the procedure is performed, as only prospective multicenter studies
will truly show which procedure may have the best overall results in the developing child. Until such studies are available,
understanding the basic pathology or the combination of pathologies leading to hydrocephalus in a given child may open the
window of opportunities for other than shunt surgery in many hydrocephalic children with major obstructive component. 相似文献
23.
侧脑室注射东莨菪碱和酚妥拉明对幼兔分辨学习的影响 总被引:3,自引:1,他引:2
目的 探讨东莨菪碱和酚妥拉明对幼兔分辨学习的影响。方法 将30只比利时纯种幼兔从生后13日龄随机分为三组:东莨菪碱组、酚妥拉明组和生理盐水对照组,观察不同日龄各组幼兔的分辨学习能力。结果 幼兔分辨学习的正确反应一般始于生后15日龄。侧脑室注射东莨菪碱对16日龄以前幼兔分辨学习无明显影响,对17日龄以后幼兔分辨学习产生明显抑制作用。侧脑室注射酚妥拉明对13—23日龄幼兔分辨学习均有明显抑制作用。结论 幼兔生后发育过程中学习能力的发展具明显的阶段性,其原因可能与神经递质系统的发育成熟有关。 相似文献
24.
Many studies have shown that health conditions experienced in childhood play an important role on an individual's adult mortality. Recent research suggests that past reductions in early life exposure to infectious diseases have been a major contributor to the historical decline in old-age mortality. Drawing on French-Canadian data from cohorts born in the 17th and 18th centuries, we test whether a progressive deterioration in early life conditions (as revealed by an increasing infant mortality rate) translates into a decrease in survival prospects in late life. We use traditional demographic measures such as the age-specific probability of death, and a series of proportional hazard models to control for familial and environmental conditions. Results point toward little evidence of any early life effects. The trend of increasing infant mortality does not correlate with a general increase of mortality in older ages within the same cohorts. Period changes affecting survival at older ages (war, epidemics) as well as demographic and biological characteristics shared within families have a much larger role in old-age mortality than early life characteristics shared within the same cohorts. 相似文献
25.
阿奇霉素替代激素治疗婴幼儿喘息性支气管炎临床研究 总被引:6,自引:0,他引:6
目的评价阿奇霉素治疗婴幼儿喘息性支气管炎的疗效并探讨其作用机制。方法婴幼儿喘息性支气管炎60例,随机分为2组,各30例,A组用阿奇霉素治疗,B组用地塞米松治疗,分别观察3d后的临床疗效;2组均测定其外周血清IL-4,IFN-γ浓度变化,并与15例健康婴幼儿(对照组)血清IL-4,IFN-γ浓度对比。结果A组与B组临床总有效率差异无统计学意义;整个喘息性支气管炎组与正常对照组相比IFN-γ和IL-4值差异均有统计学意义,IFN-γ下降,IL-4升高;各组治疗前与治疗后相比差异均有统计学意义,A组治疗后血清IFN-γ浓度增高、IL-4浓度下降;B组治疗后血清IFN-γ浓度下降、IL-4浓度也下降,且2组IFN-γ/IL-4值均显著升高。结论阿奇霉素治疗婴幼儿喘息性支气管炎有较好的疗效,能与地塞米松有同样的调节TH1及TH2细胞因子使之趋于平衡,并且有更好的促进细胞免疫作用。 相似文献
26.
27.
Ming-Shian Tsai Wen-Hsi Lin Wen-Ming Hsu Hong-Shiee Lai Po-Huang Lee Wei-Jao Chen 《Journal of gastrointestinal surgery》2008,12(12):2191-2195
Background/aims Surgical resection of choledochal cysts (CC) has become standard treatment. However, surgery is not universally recommended
in early infancy and/or asymptomatic patients. In order to investigate the optimal timing of CC excision, we analyzed clinicopathological
data and surgical results from different age groups.
Material and methods This retrospective review included 107 patients (77 females, 30 males) who underwent CC resection at the National Taiwan University
Hospital between January 1988 and December 2005. Patient demographic, clinical, and surgical data were collected and analyzed.
Results The patients were divided into three groups according to age at the time of surgery: <1 year old (group I, n = 26), 1−16 years old (group II, n = 48), and >16 years old (group III, n = 33). About two thirds of the patients in group I had jaundice, while abdominal pain related to inflammation was the commonest
symptom in groups II and III. Group I suffered significantly fewer surgical complications and less severe liver fibrosis than
groups II or III.
Conclusion CC surgery in infancy and in asymptomatic patients is safe and may prevent the complications of this condition. The results
support a recommendation for early excision. 相似文献
28.
小儿腹腔镜下疝囊高位结扎术的麻醉处理 总被引:1,自引:1,他引:0
目的探讨小儿腹腔镜下疝囊高位结扎术的麻醉处理方法和安全性。方法本组80例腹腔镜下疝囊高位结扎术患儿,ASAⅠ~Ⅱ级,以气管全麻下行术式,入室后连续监测HR、MAP、SpO2、气道峰压(PIP)、PETCO2及体温,并分别记录术前、气腹后5min、气腹后10min、放气后10min的各项监测指标。结果所有患儿麻醉均满意,无一例出现麻醉意外、并发症,CO2气腹后10、20min HR、MAP、PETCO2、PIP显著升高(p<0.05,p<0.01),SpO2无显著变化,放气后10min各项指标与术前相比差异无显著意义。结论面对小儿特殊的解剖、生理和CO2气腹对生理产生的影响,做好术前准备,选择正确的麻醉方法和合适的麻醉药物,维持稳定的循环,小儿可安全实施腹腔镜疝囊高位结扎手术。 相似文献
29.
腹腔镜辅助胆道造影在幼婴延迟性黄疸诊断中的价值 总被引:1,自引:0,他引:1
目的探讨腹腔镜辅助胆道造影在幼婴延迟性黄疸诊断中的价值。方法首先脐部置镜观察胆囊及肝脏情况,如果胆囊大小正常或基本正常,通过右肋缘下trocar孔拖出胆囊底部,部分患儿需游离胆囊系膜。切开胆囊,插管行胆道造影。如果胆囊呈纤维闭锁状态,不能拖出腹腔外,中转开腹。切开胆囊插管失败,放弃造影。结果12例患儿直接从拖出胆囊行胆道造影显示婴儿肝炎综合征或胆汁淤积8例;2例显示为胆管发育不良;2例为肝内胆管闭锁。5例从肝脏游离胆囊系膜后拖出造影,2例显示为胆管发育不良,3例提示胆道闭锁。其余21例患儿胆囊呈条索状,不同程度肝硬化,放弃胆道造影,诊断为胆道闭锁。所有胆道闭锁患儿均行Kasai手术。结论腹腔镜探查、胆道造影是诊断胆道闭锁、鉴别幼婴延迟性黄疸简便、准确、安全的方法,能够显示整个胆树的解剖结构,避免过大或不必要的创伤。 相似文献
30.
Finn Ursin Knudsen 《Brain & development》1996,18(6):312-449
Assessment of treatment strategies in febrile seizures should be based on short- and long-term outcomes, with and without acute, intermittent, or chronic medical intervention, as well as short- and long-term side effects. Febrile seizures are a benign condition with a normal neurological, motor, intellectual, and cognitive long-term outcome and have a low risk of later epilepsy in most cases. Even many complex febrile seizures have a benign outcome. Prophylaxis may or may not reduce the recurrence rate, but does not appear to improve the long-term outcome as compared to acute treatment of seizures in progress. All agree that chronic prophylaxis with anti-epileptic agents is justified only in highly selected cases, if at all. Treatment with benzodiazepines during febrile episodes appears to effectively reduce the recurrence rate, provided adequate doses are given and compliance problems minimized. A selective approach to intermittent diazepam prophylaxis seems rational, as the recurrence risk and response to treatment are highly variable. An attractive alternative is acute treatment at seizure onset with rectal diazepam in solution given by the parents at home in order to prevent prolonged recurrent seizures. This regimen has the potential of moving the first line of anti-convulsant defence close to the child. It appears to be effective, inexpensive, feasible even for non-professionals, has few side effects and is well accepted by the parents. A reasonable policy would be to treat simple febrile seizures solely with acute rectal diazepam in solution and reserve intermittent diazepam prophylaxis for selected cases including those with multiple or prolonged recurrences, several risk factors for recurrent febrile seizures and other special situations. 相似文献