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81.
This review tries to summarize the efforts over the past 20 years to construct a tissue-engineered trachea. After illustrating the main technical bottlenecks faced nowadays, we discuss what might be the solutions to these bottlenecks. You may find out why the focus in this research field shifts dramatically from the construction of a tubular cartilage tissue to reepithelialization and revascularization of the prosthesis. In the end we propose a novel concept of 'in vivo bioreactor', defined as the design of a perfusion system inside the scaffold, and explain its potential application in the construction of a tissue-engineered trachea.  相似文献   
82.
Overview Excess spasticity leads to disability that is marked by impaired locomotion, handicapping deformities and, if not controlled, discomfort and pain. Selective peripheral neurotomy in the child is indicated for severe focal spasticity, when botulinum toxin injections cannot delay surgery any longer. Materials and methods Preoperative motor blocks mimicking the outcome of the surgical procedure are essential to establish the objectives of neurotomy. In the lower limb, obturator neurotomy is indicated for spasticity in the adductor muscles, hamstring neurotomy for the knee flexion and tibial neurotomy for the spastic foot. Anterior tibial neurotomy is indicated for the extensor hallucis spasticity and femoral neurotomy for spasticity in the quadriceps. In the upper limb, neurotomy of the pectoralis major and teres major nerves is indicated for spasticity of the internal rotators of the shoulder. Neurotomy of the musculocutaneous nerve is indicated for spasticity of the flexors of the elbow, and neurotomy of median and ulnar nerves are indicated for spasticity of the pronators and flexors of the wrist and fingers. Conclusion Selective peripheral neurotomy is a valuable neurosurgical procedure in well-trained surgical hands for severe focalised spasticity.  相似文献   
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This article focuses on possible psychopharmacological interventions in the immediate post disaster setting. As there is little evidence for the efficacy or effectiveness of such interventions-given the difficulty in performing randomized, double-blind, placebo controlled studies with these populations-the article will delineate the neurobiological basis for pathological sequelae and theoretical drug interventions targeting putative disease mechanisms.  相似文献   
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We examined 53 fetuses between 15 and 40 weeks of gestation with transverse and coronal sections of the head in order to evaluate the accuracy and reproducibility of the coronal cerebellar diameter. Intraobserver coefficient of variation was less than or equal to 2.2% and the mean interobserver difference was 2.2% (range, 0 to 6%). A positive linear correlation exists between transverse and coronal measurements (coronal diameter = 1.02 x transverse diameter - 0.48; R2 = 0.99; P less than 0.0001). We conclude that the coronal cerebellar diameter is reproducible and accurate and when indicated clinically can be used instead of the transverse cerebellar diameter when the latter is not obtainable because of fetal position.  相似文献   
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Topographic order in the rat retinocollicular projection emerges from an initially diffuse projection during an early postnatal remodeling period that is coincident with the period of naturally occurring ganglion cell death. Here, we examine the relationship between a retinal axon's position along the medial-lateral axis as it enters the superior colliculus (SC) and its ability to form an appropriately positioned arbor and survive the remodeling period. At E18-E19, prior to map remodeling, axons labeled with focal DiI injections in the periphery of temporal, nasal, superior or inferior retina are widespread along the medial-lateral SC axis. At P12, after remodeling, the distributions of axons remain widespread over the medial-lateral SC axis relative to the positioning of their terminal arborizations, and resemble the distributions labeled at E18-E19, with the exception that the small proportion of axons most widely mispositioned along the medial-lateral SC axis are less frequent. These data indicate that the most widely mispositioned retinal axons are preferentially eliminated, but that a high proportion of retinal axons mispositioned along the medial-lateral axis as they enter the SC can correct their position, form topographically appropriate arbors, and survive the remodeling period.  相似文献   
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