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This case report confirms the utility of simultaneous liver transplantation in allowing successful kidney transplantation in the face of preformed, high levels of DSA, which would under normal circumstances be associated with hyperacute rejection and kidney graft failure. Antibody characterisation in terms of epitope specificity is more accurate and informative than antibodies described as “antigen-specific” and we suggest a method for identifying and tracking these antibodies; i.e. follow the epitope reaction not the antigen reactions. We consider that this will give a better insight into the behaviour and pathogenicity of HLA-specific sera. In the case presented here this approach has revealed some novel features of the post transplant antibody response in a sensitised recipient. These illustrate three phenomena which challenge current dogmas; an early resynthesis of DSA does not necessarily cause AMR, high levels of DSA can spontaneously modulate, and measurement of antibodies in terms of antigen specificity can give misleading results.  相似文献   
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The Department of Defense Familial Breast/Ovarian Cancer Research Project has offered genetic counseling and testing for BRCA1 and BRCA2 on a research basis to patients meeting specific diagnostic criteria, with risk for BRCA1 and BRCA2 mutations calculated based on the Couch model. In 2.5 years, 250 patients were evaluated and 101 patients met criteria requirements, including 33 who met criteria in more than one category. Ninety patients elected to undergo DNA testing. In this group of 90 patients, 14 mutations (15.5%) and 16 unclassified variants (17.7%) were identified. The most common inclusion criteria were onset of breast/ovarian cancer before age 45 years (n = 32) and onset of breast/ovarian cancer before age 45 years with strong family history (n = 21). However, when number of mutations and unclassified variants found were compared separately across all diagnostic criteria (including those of more than one capacity) using the chi 2 statistic, no significant differences were seen among the categories to suggest that one criterion was more predictive of mutations or variants than another. Couch risk values for patients with mutations showed a mean of 14% and ranged from 3.2 to 43.5% (range for all patients, 1.2-69.7%). These findings emphasize the importance of using multiple diagnostic criteria and suggest that a Couch risk value of > 3% may be useful in selecting patients for testing. The data also underscore the necessity of genetic counseling in the testing process, particularly given the large number of unclassified variants diagnosed and their uncertain status for disease predisposition.  相似文献   
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A novel method for estimating the susceptibility of an object by using the magnetic resonance (MR) imaging field distortions in an external-reference water bath next to the object is described. The field measurement was obtained with a phase reconstruction from a gradient-echo acquisition. A field model of an arbitrary object in a static magnetic field was discretely calculated from geometry determined from the magnitude reconstruction. Least-squares estimation yields the susceptibility of the object. Required (and proven) assumptions include validity of superposition, object homogeneity, negligible higher-order field terms, field-model accuracy, geometric-model accuracy, and correlation of gradient-echo phase to field distortion. MR susceptometry estimation of phantoms yielded susceptibility estimates that correlated well with known values (r >.9975). This MR susceptometry method is a first step toward quantitation of iron levels through MR imaging phase information in patients with iron overload.  相似文献   
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Ten patients with Wolff-Parkinson-White syndrome underwent cardiac electrophysiological study extended to include the induction of atrial fibrillation at maximum exercise in the upright position. This was performed using a new temporary bipolar lead with a helical active fixation tip for atrial pacing. The highest rate of atrioventricular conduction via the accessory pathway was greater during exercise than at rest in all 10 patients (mean increase 28%). In three cases the resulting ventricular rate exceeded 300 beats/min, but no patient had severe symptoms or ventricular arrhythmias. The exercise induced enhancement of accessory pathway conduction may significantly but unpredictably affect the risk from spontaneous atrial fibrillation especially in patients with coronary artery disease or in those taking antiarrhythmic drugs. The test procedure was sufficiently simple and well tolerated to be included in our routine electrophysiological investigation.  相似文献   
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This study aims to quantify the management and outcomes of patients treated for venous thoracic outlet syndrome (vTOS) over a seven-year period. A retrospective case-note review of all patients undergoing first rib resection at a regional vascular unit between January 1, 2002 and December 31, 2009 was performed. Treatment pathways and outcomes recorded as freedom from symptoms and venous patency were analyzed. Thirty-five patients were identified with vTOS. Ninety-one percent of patients had patent veins at discharge from clinical follow-up and were symptom-free at a median of 44 months. Patients treated within seven days of symptoms (94.7 versus 85.7, P = 0.060), with catheter-directed thrombolysis (94 versus 87.5% P = 0.702) and excision of first rib in less than 30 days (100 versus 85.7%, P = 0.002), had improved symptom-free rates. In conclusion, early referral, immediate catheter-directed thrombolysis, perioperative balloon venoplasty and early thoracic outlet decompression may provide a suitable model for improving outcomes in vTOS.  相似文献   
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Intramedullary nailing of distal metaphyseal tibial fractures   总被引:9,自引:0,他引:9  
BACKGROUND: The treatment of distal metaphyseal tibial fractures remains controversial. This study was performed to evaluate the results of intramedullary nailing of distal tibial fractures located within 5 cm of the ankle joint. METHODS: Over a sixteen-month period at two institutions, thirty-six tibial fractures that involved the distal 5 cm of the tibia were treated with reamed intramedullary nailing with use of either two or three distal interlocking screws. Ten fractures with articular extension were treated with supplementary screw fixation prior to the intramedullary nailing. Radiographs were reviewed to determine the immediate and final alignments and fracture-healing. The Short Form-36 (SF-36) and Musculoskeletal Function Assessment (MFA) questionnaires were used to evaluate functional outcome. RESULTS: Acceptable radiographic alignment, defined as <5 degrees of angulation in any plane, was obtained in thirty-three patients (92%). No patient had any change in alignment between the immediate postoperative and the final radiographic evaluation. Complications included one deep infection and one iatrogenic fracture at the time of the intramedullary nailing. Six patients could not be followed. The remaining thirty fractures united at an average of 23.5 weeks. Three patients with associated traumatic bone loss underwent a staged autograft procedure, and they had fracture-healing at an average of 44.3 weeks. The functional outcome was determined at a minimum of one year for nineteen patients and at a minimum of two years (average, 4.5 years) for fifteen patients. At one year, there were significant limitations in several domains despite fracture union and maintenance of alignment, but there was improvement in the MFA scores with time. CONCLUSIONS: Intramedullary nailing is an effective alternative for the treatment of distal metaphyseal tibial fractures. Simple articular extension of the fracture is not a contraindication to intramedullary fixation. Functional outcomes improve with time.  相似文献   
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