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1.
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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BACKGROUND: With the popularity of laser skin resurfacing for the correction of photoaging and the improvement of acne scarring, it is important to note complications that may result from this procedure. Infections must be recognized and treated early, as some can result in permanent local destruction and systemic spread to other body sites. OBJECTIVE: To increase the awareness of an unusual infection that may result from laser resurfacing. METHODS: We report the case of a 52-year-old woman who presented with two symmetrical nodules 1 month after full-face skin resurfacing with CO2 laser. These were found to be abscesses caused by Mycobacterium fortuitum infection. RESULTS: The diagnosis was established following surgical debridement and subsequent culture grown from the exudate. Oral antibiotic treatment guided by organism sensitivity resulted in complete clearance of the infection with no recurrence or sequelae after 3 years of follow-up. CONCLUSION: This case demonstrates that atypical mycobacterial infections may arise after laser resurfacing procedures, despite proper technique, sterile instrumentation, and appropriate perioperative medications and postoperative wound care. If diagnosed and treated early, this potentially disastrous complication can be cured with no permanent sequelae.  相似文献   
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BACKGROUND: Twenty subjects were treated with either polidocanol (POL) or sodium tetradecyl sulfate (STS) to compare the efficacy and adverse sequelae of each agent. OBJECTIVE: To determine the safety and efficacy of two widely used sclerosing agents. METHODS: After the exclusion of saphenofemoral junction incompetency, each subject's leg veins were categorized by size (< 1, 1-3, and 3-6 mm in diameter). Each leg was then randomized to be treated with 0.5%, 1%, or 1% foam of POL or 0.25%, 0.5%, or 0.5% foam of STS according to vein size. An independent panel of four physicians, blinded to treatment, performed randomized photographic evaluations obtained pretreatment and 12 weeks post-treatment. Subject satisfaction index and overall clinical improvement assessment were also obtained. RESULTS: An average 83% improvement was noted for all vein sizes in all subjects with both POL and STS after a single treatment. Subjects were satisfied with treatment, regardless of the sclerosing agent used or the vein size treated. There was no statistically significant difference in adverse effects between each group. CONCLUSION: Both POL and STS are safe and effective sclerosing agents in the treatment of varicose and telangiectatic leg veins. Both are very tolerable and demonstrate similar post-treatment sequelae.  相似文献   
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A new commercial test for the diagnosis of rotavirus gastroenteritis was assessed. With some modifications it compared favourably with electron microscopy and immunofluorescence.  相似文献   
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Competitive control of the self-renewing T cell repertoire   总被引:1,自引:0,他引:1  
We develop a mathematical model for the self-renewing part of the T cell repertoire. Assuming that self-renewing T cells have to be stimulated by immunogenic MHC-peptide complexes presented on the surfaces of antigen-presenting cells, we derive a model of T cell growth in which competition for MHC-peptide complexes limits T cell clone sizes and regulates the total number of self-renewing T cells in the animal. We show that for a sufficient diversity and/or degree of cross-reactivity, the total T cell number hardly depends upon the diversity of the T cell repertoire or the diversity of the set of presented peptides. Conversely, for repertoires of lower diversity and/or cross-reactivity, steady-state total T cell numbers may be limited by the diversity of the T cells. This provides a possible explanation for the limited repertoire expansion in some, but not all, mouse T cell re-constitution experiments. We suggest that the competitive interactions described by our model underlie the normal T cells numbers observed in transgenic mice, germ-free mice and various knockout mice.   相似文献   
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Allergen Poa p I isolated from the dialysed aqueous extract of Kentucky blue grass pollen by affinity chromatography with an anti-Lol p I murine monoclonal antibody (MAb) 290A-167 was previously shown to consist of a 35.8-kilodalton (kD) component with a pI of 6.4, designated as Poa p Ia, and a 33-kD component with a pI of 9.1, designated as Poa p Ib. The present study reports on the comparative antigenic analyses of these two components, using MAbs produced separately against Poa p I and Lol p I. Thus, anti-Poa p I MAbs 60 and 61 and anti-Lol p I MAb 290A-167 recognized Poa p Ia and Poa p Ib whereas anti-Poa p I MAbs 62, 63 and 64 and anti-Lol p I MAb 348A-6 recognized only Poa p Ia. The specificities of the MAbs were further resolved by comparing their respective abilities to inhibit the binding of 125I-Poa p I or 125I-Lol p I to the different MAbs prepared in the form of solid phase. These studies revealed that at least 4 distinct epitopes (designated as E1, E2, E3 and E4) were shared by both Poa p I and Lol p I. All 4 epitopes were present on Poa p Ia whereas only E1 and E3 were detected on Poa p Ib. E1 was recognized by MAbs 60 and 61, E2 by MAbs 62, 63 and 64, E3 by MAb 290A-167 and E4 by MAb 348A-6.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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