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The usual method for popliteal artery aneurysm exclusion is distal and proximal ligation followed by bypass grafting via a medial approach. This technique preserves collaterals to the aneurysm, which might cause back-bleeding and symptomatic enlargement. We report the eighth case in the literature of a ruptured popliteal artery aneurysm after previous ligation and bypass grafting. The ruptured aneurysm was successfully excluded via a posterior approach. The advantage of this approach over the medial approach is the possibility of opening the aneurysm sac to oversew patent side branches, thereby excluding back-bleeding. We review the advantages and disadvantages of both the medial and the dorsal technique to treat popliteal aneurysms.  相似文献   
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OBJECT: In nearly all patients with glioblastoma multiforme (GBM) a local recurrence develops within a short period of time. In this paper the authors describe two patients in whom a second GBM developed after a relatively long time interval at a site remote from the primary tumor. The genetic profiles of the tumors were compared to discriminate between distant recurrence and a second primary tumor. METHODS: Both patients harboring a supratentorial GBM were treated with surgery and local high-dose radiotherapy. Local control of the disease at the primary tumor site was achieved. Within 2 years, a second GBM developed in both patients, not only outside the previously irradiated target areas but infratentorially in one patient and in the opposite hemisphere in the other. The tumors were examined for the presence of several genetic alterations that are frequently found in GBMs--a loss of heterozygosity at chromosome regions 1p36, 10pl5, 19q13, and 22q13, and at the CDKN2A, PTEN, DMBT1, and TP53 gene regions; a TP53 mutation; and EGFR amplification. In the first patient, genetic profiling revealed that the primary tumor had an allelic imbalance for markers in several chromosome regions for which the second tumor displayed a complete loss. In the second patient, genetic profiling demonstrated the presence of genetic changes in the second tumor that were identical with and additional to those found in the primary tumor. CONCLUSIONS: Based on the similarities between the genetic profiles of the primary and the second tumors in these patients, the authors decided that in each case the second distant GBM was a distant recurrence rather than a second independent primary tumor.  相似文献   
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The neural cell adhesion molecule L1 is a transmembrane glycoprotein belonging to the immunoglobulin superfamily of cell adhesion molecules (CAMs). Its expression is essential during embryonic development of the nervous system and it is involved in cognitive function and memory. Mutations in the L1CAM gene are responsible for four related L1 disorders; X-linked hydrocephalus/HSAS (Hydrocephalus as a result of Stenosis of the Aqueduct of Sylvius), MASA (Mental retardation, Aphasia, Shuffling gait, and Adducted thumbs) syndrome, X-linked complicated spastic paraplegia type I (SPG1) and X-linked Agenesis of the Corpus Callosum (ACC). These four disorders represent a clinical spectrum that varies both between and within families. The main clinical features of this spectrum are Corpus callosum hypoplasia, mental Retardation, Adducted thumbs, Spastic paraplegia and Hydrocephalus (CRASH syndrome). Since there is no biochemically assayed disease marker, molecular analysis of the L1CAM gene is the only means of confirming a clinical diagnosis. Most L1CAM mutations reported to date are point mutations (missense, nonsense, splice site) and only a few patients with larger rearrangements have been documented. We have characterised a rare intragenic deletion of the L1CAM gene in a sample of DNA extracted from a chorionic villus biopsy (CVB) performed at 12 weeks' gestation. =  相似文献   
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Two experiments were carried out to investigate whether cigarette smoking could produce state-dependent learning (SDL) in humans. The first experiment was concerned with the methodological issue of choosing an appropriate control cigarette for use in an SDL design. A low nicotine content (0.2 mg) cigarette was chosen as it did not appear to affect the physiological arousal of the subjects. In Experiment 2, it was shown that cigarette smoking can produce state-dependent memory effects. The most likely basis for the results is the arousal produced by the nicotine content of the cigarette.  相似文献   
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