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51.
Tuberous sclerosis is an inherited neurocutaneous disorder characterized by seizures, mental retardation, cutaneous lesions and visceral hamartomas. We describe a 17-year-old boy in whom polycystic kidneys of the adult type were fortuitously detected on routine check-up. The patient enjoyed good health and had no evidence of renal dysfunction. Closer scrutiny of his past history and his physical and laboratory findings disclosed that he had tuberous sclerosis. Our case adds to the scant reported experience with the association of tuberous sclerosis and adult-type polycystic kidneys, and suggests that a search of additional manifestations of tuberous sclerosis is warranted in children in whom adult-type polycystic renal disease is detected. 相似文献
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In a previous study of the radiologic evaluation of children with urinary tract infection it was recommended that IVP be performed in all patients with either abnormal ultrasonographic or voiding cystourethrographic findings. However, the benefit from IVP was believed to be questionable in children with normal ultrasonography findings and vesicoureteral reflux of only a low grade (I or II of V). To gain a better understanding of the need for IVP in the radiologic evaluation of such children, the database was expanded and the findings concerning ultrasonography and IVP were analyzed in 52 children with urinary tract infection and vesicoureteral reflux seen during the last 3 years. Of a total of 72 instances of reflux, 44 (61.1%) were of low grade (I or II), 14 of medium grade (III), and 14 of high grade (IV or V). Of the 44 urinary systems with low-grade reflux, results were as follows: renal ultrasonography appeared normal in 38 and in 34 of these, the IVP also appeared normal; in the other four, only minor and negligible changes were seen with IVP. Surgical intervention was not necessary in any of these 38 urinary systems. In six systems with low-grade vesicoureteral reflux but with abnormal ultrasonography findings, IVP results were also abnormal, and surgery was necessary in two instances. Of the 14 urinary systems with medium-grade reflux, ultrasonography appeared normal in ten but in six of these the IVP appeared abnormal.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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One of the major challenges in the field of neurally driven evolved autonomous agents is deciphering the neural mechanisms underlying their behavior. Aiming at this goal, we have developed the multi-perturbation Shapley value analysis (MSA)--the first axiomatic and rigorous method for deducing causal function localization from multiple-perturbation data, substantially improving on earlier approaches. Based on fundamental concepts from game theory, the MSA provides a formal way of defining and quantifying the contributions of network elements, as well as the functional interactions between them. The previously presented versions of the MSA require full knowledge (or at least an approximation) of the network's performance under all possible multiple perturbations, limiting their applicability to systems with a small number of elements. This article focuses on presenting new scalable MSA variants, allowing for the analysis of large complex networks in an efficient manner, including large-scale neurocontrollers. The successful operation of the MSA along with the new variants is demonstrated in the analysis of several neurocontrollers solving a food foraging task, consisting of up to 100 neural elements. 相似文献
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This article investigates the evolution of autonomous agents that perform a memory-dependent counting task. Two types of neurocontrollers are evolved: networks of McCulloch-Pitts neurons, and spiking integrate-and-fire networks. The results demonstrate the superiority of the spiky model in evolutionary success and network simplicity. The combination of spiking dynamics with incremental evolution leads to the successful evolution of agents counting over very long periods. Analysis of the evolved networks unravels the counting mechanism and demonstrates how the spiking dynamics are utilized. Using new measures of spikiness we find that even in agents with spiking dynamics, these are usually truly utilized only when they are really needed, that is, in the evolved subnetwork responsible for counting. 相似文献
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Casap N Kreiner B Wexler A Kohavi D 《The International journal of oral & maxillofacial implants》2006,21(2):314-319
This article presents a technique for the removal of the screws used to fix a bone graft and for the placement of dental implants in a flapless approach that utilizes the tracking technology of a computerized navigation system. A 24-year-old female patient injured in a terrorist bombing suffered from tooth loss and a bone defect in the maxilla. The area was grafted with bone from the chin in preparation for the placement of dental implants. Four months following the grafting procedure, the fixing screws were removed and the dental implants were placed in a flapless approach by the application of a specialized computerized navigation system. This technique emphasizes the potential of computerized navigation approaches in the facilitation of minimally invasive oral surgery. 相似文献
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Alon T Bagchi D Preuss HG 《Research communications in molecular pathology and pharmacology》2002,111(1-4):139-151
Beta-hydroxy-beta-methylbutyrate, more commonly referred to as HMB, is derived from the amino acid, leucine, and its keto acid, alpha-ketoisocaproate. In several studies combining HMB supplementation and resistance exercise, researchers have concluded that HMB may play an important role in reducing protein degradation and/or increasing recovery of damaged muscle cells. These actions could be advantageous to all individuals participating in exercise programs and improve the lives of many by overcoming weakness or frailty. 相似文献