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101.
HIV transmission from mother-to-child remains a major cause of infant morbidity and mortality in resource-poor settings. There is consensus that women who need antiretroviral treatment should receive this during pregnancy and beyond, and that an appropriate antiretroviral prophylactic regimen should be given to those who do not yet need ongoing therapy. Infant feeding remains a major source of infection and new antiretroviral strategies, for mothers or children, are emerging with the potential to control this. Access to HIV testing and antiretroviral treatment or prophylaxis remain very limited in low resource settings and needs to be expanded.  相似文献   
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Background: Health care workers (HCWs) in Armed Forces are immunised against Hepatitis B virus (HBV), however they are not subjected to anti-HBs (antibody to Hepatitis B surface antigen) assessment after primary vaccination. The present study was undertaken to determine the protection offered by HBV vaccine in HCW.  相似文献   
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1 Introduction Concussion is both the most common and most puz- zling type of mild traumatic brain injury (MTBI), with its nature still under drastic debate now[1]. Though the cogni- tive and memory functions were impaired in humans[2], thekey research focus is on the “miserable minority”[3] who suffer from acute concussion that is often presented with a variety of persistent physical, emotional, and cognitive symptoms. It is uncertain if these post concussional syn- dromes (PCS) are gene…  相似文献   
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Sham  RL; Phatak  PD; Ihne  TP; Abboud  CN; Packman  CH 《Blood》1993,82(8):2546-2551
Interleukin-8 (IL-8), a recently described peptide cytokine, is a neutrophil chemoattractant and activator that exerts effects similar to fMLP, yet their receptors and their roles in pathophysiology differ. The effect of IL-8 on the neutrophil cytoskeleton has not been well studied; therefore, we compared and contrasted the effects of IL-8 and fMLP on neutrophil actin conformation and on the signal pathway regulation of actin responses. IL-8 caused a rapid, dose-dependent increase in neutrophil F-actin content within 30 seconds. The maximum increase was twofold. These changes were accompanied by the development of F-actin-rich pseudopods, as noted with fluorescence microscopy and scanning electron microscopy. Selected biochemical inhibitors were used to study the regulation of the IL-8-induced actin changes. Incubation of neutrophils with 2 micrograms/mL pertussis toxin resulted in a 67% inhibition of the IL-8-induced F-actin increase. The protein kinase C (PKC) inhibitors, staurosporine and H7, did not inhibit the increase in F-actin caused by IL-8. IL-8 caused a rapid increase in neutrophil intracellular calcium that could be completely inhibited by the chelating agent 1,2-bis(o-aminophenoxy)ethane-N,N-N',N'-tetraacetic acid (BAPTA). However, BAPTA-treated neutrophils retained the ability to increase F-actin in response to IL-8. Similar results were seen with fMLP, indicating that, similar to fMLP, the IL-8-induced actin response is mediated through pertussis-toxin-sensitive G-proteins but is neither dependent on PKC nor increases in cytosolic calcium. Thus, although IL- 8 and fMLP exert their effects on neutrophils through different receptors, the signal transduction pathways used and the effects on actin conformation and pseudopod formation are similar.  相似文献   
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Aims: To compare, using a decision model, performance, treatment pathways and effects of different newborn screening strategies for developmental hip dysplasia with no screening. Methods: Detection rate, radiological absence of subluxation at skeletal maturity and avascular necrosis of the femoral head, as favourable and unfavourable treatment outcomes respectively, were compared for the following strategies: clinical screening alone using the Ortolani and Barlow tests; the addition of static and dynamic ultrasound examination of the hips of all infants (universal ultrasound) or restricted to infants with defined risk factors (selective ultrasound); "no screening" (that is, clinical diagnosis only). Results: Universal or selective ultrasound detects more more affected children (76% and 60% respectively) than clinical screening alone (35%), results in a higher proportion of affected children with favourable treatment outcomes (92% and 88% respectively) than clinical screening alone (78%) or no screening (75%), and the highest proportion of these achieved without recourse to surgery (64% and 79% respectively) compared with clinical screening alone (18%). However, ultrasound based strategies are also associated with the highest number of unfavourable treatment outcomes arising in unaffected children treated following a false positive screening result. The detection rate of clinical screening alone becomes similar to that reported for universal ultrasound when based on studies using experienced examiners (80%) rather than junior medical staff (35%). Conclusion: From the largely observational data available, ultrasound based screening strategies appear to be most sensitive and effective but are associated with the greatest risk of potential adverse iatrogenic effects arising in unaffected children.  相似文献   
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EPP:一个与表情特征加工相关的ERPs晚期正成分   总被引:2,自引:0,他引:2  
目的 研究与表情特征加工相关的事件相关脑电位(event-related potentials,ERPs)成分。方法 被试者为12名(7男5女)右利手健康大学生。刺激包括3种卡通面孔(中性、微笑、愤怒)和3种非面孔。要求被试者进行面孔识别(face recognition,FR)和面孔表情分类(facial expression classification,FEC)2种作业。记录32导脑电。结果 1)与FR任务相比,FEC任务产生明显的P580成分;2)FEC的ERP与FR的ERP的差异波形,表现出一个非常明显的中央一顶区分布的正差异(450~850ms),命名为表性加工正成分(expression processing positivity,EPP);3)EPP的峰值潜伏期表现出明显的表情特征主效应,以愤怒面孔EPP的潜伏期最短,微笑面孔EPP的潜伏期最长。结论 EPP可能反映了表情特征的晚期加工。  相似文献   
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