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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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Conclusions  Noninvasive imaging of neurohumoral upregulation in remodeled myocardium suggests that an imaging strategy can be developed for predicting the rate of remodeling and likelihood of HF development. This should allow a more judicious use of neurohumoral antagonists especially in subjects who do not have manifest HF.74 In others specific targeted imaging may allow timely selection of individualized treatment strategies and ensure optimization of therapeutic intervention. Similar to ACE and AII receptors, multiple other targets in the hormonal cascades can identify the likelihood of adverse and favorable remodeling.74  相似文献   
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The intestinal uptake of [14C]oxalate, [14C]glyoxylate, and [14C]glycolate are studied in brush border membrane vesicles (BBMV) isolated from vitamin A-deficient and pair-fed control rats. The data obtained indicate that oxalate and its precursors are transported across the BBMV by passive diffusion. The intestinal uptake of glyoxylate and glycolate remains unaltered in vitamin A deficiency, while uptake rate of oxalate was significantly increased (p less than 0.01) in vitamin A-deficient rats as compared to pair-fed controls. In conclusion, the results indicate that vitamin A deficiency leads to hyperabsorption of oxalate through the gut.  相似文献   
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Impact of pediatricians' attire on children and parents   总被引:1,自引:0,他引:1  
To evaluate perceptions of a pediatrician's attire, 50 children and parents in an outpatient facility were shown five photographs of a female or a male physician dressed differently (formal to informal). A list of positive and negative attributes was presented to the parents and children who were to match each picture to the attributes. Parents had a strong positive preference for the formally dressed female (short white coat and skirt), and the formally dressed male (short white coat and tie). More than 50% of the parents least preferred the most informal attire. Children had no clear preferences for males and preferred the female in the blouse and skirt. Children assigned negative attributes to informal attire but not to the same degree as did their parents. This study demonstrates that parents have stronger preferences than do their children. Although children had no strong positive preferences, they may feel negatively about informal attire.  相似文献   
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Background  Similar to other99mTc-based infarct-avid agents,99mTc-glucarate localizes in myocardial infarcts. Whether severely ischemic viable myocytes sequester99mTc-glucarate is uncertain. To assess the infarct specificity, in vitro and in vivo studies were performed. Methods and Results  H9C2 embryonic rat cardiocytes cultured under normoxia (N) or hypoxia (H) for 24 hours in 7.5 μCi99mTc-glucarate were compared with necrotic cardiocytes. Mean H/N ratio (3.0±0.004, mean±SD) was significantly less than that of the necrotic/N ratio (39.9±6.5,p<0.01). Reperfused myocardial infarction (MI) in 4 dogs confirmed by201Tl, (0.5 to 1.0 mCi) scintigraphy were imaged serially, with simultaneously injected mixture of99mTc-glucarate and111In-antimyosin Fab. Infarcts were detected scintigraphically within 4 to 10 minutes with99mTc-glucarate.111In-antimyosin required more than 1 hour. Myocardial distribution at 5 hours showed a direct correlation between99mTc-glucarate and111In-antimyosin uptake (r=0.99,p<0.0001). Both99mTc-glucarate (r=−0.777,p<0.0001) and111In-antimyosin (r=−0.775,p<0.0001) were inversely related to201Tl distribution. Conclusions  The near perfect correlation between99mTc-glucarate and111In-antimyosin uptake (r=0.99) in reperfused canine MI and the insignificant glucarate uptake by viable cardiocytes in vitro attest to the avidity of99mTc-glucarate for the necrotic myocardium and favor its use as a specific early marker of myocyte necrosis in acute MI. Supported in part by SBIR grant 1R43-HL54410-01 and Molecular Targeting Technology, Inc.  相似文献   
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