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Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed.  相似文献   
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Coronary artery bypass grafts: visualization with MR imaging   总被引:1,自引:0,他引:1  
Gomes  AS; Lois  JF; Drinkwater  DC  Jr; Corday  SR 《Radiology》1987,162(1):175
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We report the case of a 20-year-old man with an ipsilateral mid-third clavicle fracture with grade V acromioclavicular joint (ACJ) dislocation. The combination of these two injuries is rare. A literature search produced various treatment algorithms. In this case, the patient was successfully treated with a Bosworth screw.This work was carried out in the Department of Orthopaedics, William Harvey Hospital, Ashford, Kent, UK  相似文献   
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The immediate surgical goals in the treatment of thoraco-lumbar fractures are decompression of compromised neural structures and stabilization of the vertebral column. If more sophisticated instrumentation is available, e.g. A.O.-fixateur interne or instrument set according to Kluger, stable reposition and reformation of compressed vertebral bodies also becomes possible. The long-term goals are to prevent delayed onset of spinal deformity, pain, and further neurological deficit. Early operative stabilization also shortens hospitalization time and allows immediate ambulation, thus lessening pulmonary, vascular, urological, and psychological complications. The Department of Neurosurgery, Sher-I-Kashmir Institute of Medical Sciences, treated 75 cases of thoraco-lumbar fractures. Out of 75 cases 63 were operated upon: 32 cases by spinal fusion alone and 31 by a combined procedure of decompression and posterior spinal fusion with fibular graft. 52 showed evidence of recovery ranging from moderate to excellent in a follow-up of 2-3 years. Thus surgery resulted not only in giving a stable spine to patients but also good improvement of neurodeficits. Our experiences demonstrate that operative treatment of thoraco-lumbar fractures can give satisfactory results even in situations where sophisticated instrumentation is not available.  相似文献   
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PURPOSE: The aim of the study was to delineate differences in saccadic adaptation characteristics between a population of racquet sports athletes and nonathletes. METHODS: Eye movements were recorded at 120 Hz using a video-based eye tracker (ELMAR 2020) in a sample of 27 athletes (varsity badminton and squash players) and 14 nonathletes (<3 hours/week participation in recreational sports). Responses to negative positional error and positive positional error were studied in two sessions on separate days. Negative positional errors were induced by displacing the stimuli backwards by 3 degrees from the initial target step (12 degrees). Likewise, positive positional errors were induced by displacing the stimuli forward by 3 degrees . Amplitude gains were calculated for trials before, during, and after the adaptation phase. The magnitude and the rate of change of saccadic adaptation were determined from the amplitude gains. Differences between the groups were compared using regression analysis. RESULTS: No significant differences were found between the two groups in the magnitude of saccadic adaptation, both for negative (athletes -60%, nonathletes -57%) and positive (athletes +26%, and nonathletes +27%) positional error. Racquet sports athletes showed a significantly faster rate of adaptation for the positive positional error. A significant difference was not observed in the rate of adaptation for the negative positional error. CONCLUSIONS: Racquet sports athletes and nonathletes adapt to positional error signals by similar amounts. However, racquet sports athletes respond to positive positional errors at a faster rate, suggesting that a strategic component or environmental influences (such as practice) may play a role in saccadic adaptation.  相似文献   
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