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991.
We describe two children diagnosed with effusive–constrictive epicarditis that developed more than 5 years after ventricular septal defect (VSD) closure. Constrictive epicarditis is extremely rare in children and there are few reports of infants with effusive–constrictive epicarditis associated with congenital heart disease surgery. This is the first pediatric case report of effusive–constrictive epicarditis occurring after VSD closure that was relieved by epicardiectomy.  相似文献   
992.
In the treatment of Hirschsprung’s disease, transanal endorectal pull-through (TEPT) is being performed without laparoscopic assistance or laparotomy for short-segment aganglionosis. Preoperative ascertainment of the extent of aganglionosis is required, as this affects the planning for TEPT. The present study investigated the usefulness of preoperative endoscopic marking as an intraoperative marker of the location of pull-through. Since 1998, we have performed TEPT using a prolapsing technique for the treatment of Hirschsprung’s disease. Subjects comprised 17 patients with short-segment aganglionosis and 2 patients with long-segment aganglionosis in whom endoscopic marking was performed preoperatively. Median age at time of surgery was 2.7 months. The relationship between pathologic findings at the marked area and location of actual pull-through was investigated. For endoscopic marking, each patient was sedated using intravenous ketamine hydrochloride. The junction between normal bowel with peristalsis and aganglionic bowel without peristalsis (“shorebreak” finding) was marked by either tattooing or clipping. Normal ganglion cells were seen in the marked area of 14 patients, and pull-through was performed at the marked area in each of these patients. In three patients, ganglion cells existed in the marked area, but the number of ganglion cells was considered insufficient. Additional frozen sections were thus prepared to ascertain the area with normal ganglion cells, showing that normal ganglion cells were seen 1, 3 or 5 cm proximal to the marked area. In one patient, no ganglion cells were seen in the marked area, but were present 5 cm proximal to the marked area. In the remaining one patient, normal ganglion cells were seen 7 cm distal to the marked area. Pathologic findings revealed ganglion cells at the shorebreak finding in 17 of the 19 patients (89.5%), suggesting that this junction basically matches the distribution of ganglion cells. Endoscopic marking of the junction is very useful for determining the tip of pull-through.  相似文献   
993.
994.
Several lines of evidence suggest that D-serine, an endogenous agonist of the glycine site on the NMDA receptors, might play a role in the pathophysiology of schizophrenia. The purpose of this study was to determine whether levels of D- and L-serine or D-serine ratio (D-serine/total serine) in cerebrospinal fluid (CSF) were altered in first episode and drug-naive schizophrenic patients. The CSF levels of D- and L-serine in 25 male first episode and drug-naive schizophrenic patients and 17 age-matched male healthy subjects were measured using a column-switching high performance liquid chromatography system. The percentage of D-serine in the total serine of patients was significantly (z = -2.01, p = 0.044) lower than that of controls. This study suggests that synthetic or metabolic pathways of D-serine may be abnormal in the brain of drug-naive schizophrenic patients, supporting the NMDA receptor dysfunction hypothesis of schizophrenia.  相似文献   
995.
The 1p36 deletion syndrome is a newly delineated multiple congenital anomalies/mental retardation syndrome characterized by mental retardation, growth delay, epilepsy, congenital heart defects, characteristic facial appearance, and precocious puberty. We analyzed 11 patients by fluorescence in situ hybridization (FISH) using commercially available bacterial artificial chromosome and P1-derived artificial chromosome genomic clones to define the chromosomal deletion responsible for the 1p36 deletion syndrome. Cytogenetic investigation revealed two cases with a terminal deletion of 1p36. Nine patients had an apparently normal karyotype with standard G-bands by trypsin using Giemsa (GTG), but FISH screening with the highly polymorphic genetic marker D1Z2, which is mapped to 1p36.3 and contains an unusual reiterated 40-bp variable number tandem repeat, revealed a submicroscopic deletion. All patients had severe to profound mental retardation. Based on the University of California Santa Cruz Genome Browser, we constructed a deletion map and analyzed the relationship between neurological findings and chromosomal deletions for the 11 cases. Six cases had intractable epilepsy and three had no seizures. The common deletion interval was about 1 million base pairs (Mbp) located between RP11-82D16 and RP4-785P20 (Rho guanine exchange factor (GEF) 16). The severity of clinical symptoms correlates with the size of the deletion. This is demonstrated by the 3 patients with at least 8Mbp deletions that display profound mental retardation and congenital heart defects. Although haploinsufficiency of the potassium channel beta-subunit (KCNAB2) is thought to be responsible for intractable seizures in the 1p36 deletion syndrome, this was not the case for 3 of the 11 patients in this study. Further investigation of the 1p36 region is necessary to allow identification of genes responsible for the 1p36 deletion syndrome.  相似文献   
996.
Among patients with familial amyloid polyneuropathy (FAP), those with transthyretin Val30Met mainly show distally predominant weakness and atrophy, whereas some FAP patients, including those with transthyretin Ser50Ile and Tyr114Cys, show muscle weakness and atrophy that is dominant proximally, simulating myopathy. To clarify the cause of proximally dominant muscular atrophy in patients with FAP transthyretin Ser50Ile and Tyr114Cys, we investigated the distinctive features of muscle specimens of patients with FAP, 3 of who had Val30Met, 2 Ser50Ile, and 2 Tyr114Cys transthyretin. All specimens showed transthyretin amyloid around blood vessels and perimysium, and neurogenic denervation patterns. The amount of amyloid around the vessels was much greater in patients with FAP Ser50Ile and Tyr114Cys than in Val30Met patients. Muscular amyloid angiopathy may contribute to motor nerve injury that, in turn, may lead to amyotropic changes in patients with FAP Ser50Ile and Tyr114Cys.  相似文献   
997.
AIM: To investigate the usefulness of high-resolution MR imaging in the evaluation of the extracranial facial nerve, compared with surgical findings. MATERIALS AND METHODS: Thirteen patients with benign parotid tumours were studied on a 1.5-T MR system with a 3 in circular surface coil. High-resolution T1-weighted spin-echo, T2-weighted fast spin-echo, and three-dimensional gradient-recalled acquisition in the steady state (GRASS) images were obtained in the axial planes. Oblique reformatted images were generated. Tumours, parotid ducts and facial nerves were identified on these images. The relationship of the tumours to the facial nerves was confirmed at surgery. RESULTS: Facial nerves appeared as linear structures of low intensity on all pulse sequences. The main trunks and cervicofacial and temporofacial divisions of the facial nerves were identified in 100%, 84.1% and 53.8% of GRASS images, respectively. Parotid ducts appeared as structures of low intensity on T1-weighted (66.6%) and GRASS images (81.8%), and as structures of very high intensity on T2-weighted images (91.7%). The relationships of the tumours to the facial nerves were correctly diagnosed in 11 (91.7%) of 12 cases. CONCLUSION: High-resolution MR imaging depicts the extracranial facial nerve and the parotid duct, and is useful for preoperative evaluation of parotid gland tumours.  相似文献   
998.
We describe a case of carbon monoxide poisoning that led to pallidoreticular damage and delayed leukoencephalopathy. Serial diffusion-weighted MR imaging was performed. A restricted water diffusion pattern was demonstrated in the globus pallidus and substantia nigra in the early stage. Diffusion-weighted imaging is useful for early identification of the effects of acute carbon monoxide poisoning.  相似文献   
999.
BACKGROUND: The contact pressure and contact area at the tendon-bone interface after the most commonly used rotator cuff repair methods have not been investigated. HYPOTHESIS: There are no significant differences among the transosseous, the single-row suture anchor, and the double-row suture anchor techniques in terms of contact pressure, contact area, and pressure patterns at the tendon-bone interface. STUDY DESIGN: Controlled laboratory study. METHODS: After creating a full-thickness supraspinatus tendon tear in 10 cadaveric shoulder specimens, we inserted pressure-sensitive film between the tendon stump and the bone, and we repaired the tear by (1) transosseous, (2) single-row suture anchor, and (3) double-row suture anchor techniques. RESULTS: The contact area of the double-row technique was 42% greater than that of the transosseous technique (P < .0001) and 60% greater than that of the single-row technique. The contact area of the transosseous technique was 31% greater than that of the single-row technique (P = .0015). The average pressures of the single-row and double-row techniques were 18% (P = .014) and 16% (P = .03) greater, respectively, than that of the transosseous technique, but there was no significant difference between the single-row and double-row techniques (P = .915). CONCLUSIONS: The double-row technique produced the greatest contact area and the second-highest contact pressure, whereas the single-row technique created the highest contact pressure and the least contact area. The transosseous technique produced the second-greatest contact area and the least contact pressure. CLINICAL RELEVANCE: The double-row suture anchor technique and the transosseous technique may provide a better environment for tendon healing.  相似文献   
1000.
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