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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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3.
Soft tissue sarcomas of the head and neck in adults   总被引:1,自引:0,他引:1  
We reviewed the clinical records and pathologic material of 176 adults with primary soft tissue sarcomas treated at Memorial Sloan-Kettering Cancer Center between 1950 and 1985. Seventy-two patients (41%) had low-grade sarcomas and 104 (59%) had high-grade sarcomas. All but 18 patients underwent some form of excision as initial therapy. Adjuvant radiotherapy and chemotherapy combined with surgical excision showed no significant effect. A significantly increased risk of treatment failure was associated with large tumor size, positive surgical margins, bone involvement, local recurrence, metastatic spread, and high histologic grade. Except for recurrence, the p value by univariate analysis in the log-rank test for comparison of survival according to these clinical and pathologic characteristics was p less than 0.0001. Although the overall survival was 75% at 2 years, 55% at 5 years, and 46% at 10 years, only 20% of the patients with high-grade sarcomas were alive 10 years after treatment. Most patients with rhabdomyosarcoma, high-grade peripheral nerve tumor, and high-grade fibrous histiocytoma and all patients with high-grade angiosarcoma died of disease less than 5 years after diagnosis. New therapeutic strategies are needed to improve the survival of adult patients with high-grade soft tissue sarcomas of the head and neck.  相似文献   
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Melatonin was detected by radioimmunoassay in the gastrointestinal tract (GIT) of several species of fish (sturgeon, rainbow trout, carp), amphibians (axolotl, leopard frog, bullfrog), and one reptile (red-sided garter snake), which were sacrificed during the daytime. The highest levels of melatonin were detected in the snake [means = 1018 pg/g stomach, 328 pg/g proximal gut (PG), 511 distal gut (DG)] and carp (means = 102 pg/g stomach, 146 pg/g PG and 141 pg/g DG). Lowest levels were found in the axolotl (means = 44 pg/g stomach and PG, 92 pg/g DG) and the bullfrog (means = 73 pg/g esophagus, 78 pg/g stomach, 20 pg/g PG, and 152 pg/g DG). In most cases there were no statistically significant differences in the melatonin levels among various GIT tissues of the same species but there were differences in tissue levels between different species.  相似文献   
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We report on the development of features of the postpericardiotomy syndrome following coronary perforation during balloon angioplasty, in a patient that was managed conservatively. The case illustrates that while cardiac tamponade does not invariably follow coronary perforation, late consequences derived from this complication may occur. It also widens the spectrum of conditions where the postpericardiotomy syndrome has been observed.  相似文献   
9.
Summary A phase II study of high-dose ifosfamide in hepatocellular carcinoma was conducted among 17 Chinese patients. The dose of ifosfamide used was 2.5 g/m2 daily given as a continuous infusion for 5 days. In all, 15 patients were evaluable for tumour response. There was no complete or partial responder. The treatment was well tolerated. The most frequent toxicity was alopecia, which occurred in 11 patients, and 5 patients developed mild haematological toxicity. There was no evidence of liver or bladder toxicity. Overall, 14 patients were evaluable for survival. The median survival was 92 days (range, 30–568 days). We conclude that high-dose ifosfamide is well tolerated but ineffective in hepatocellular carcinoma in Chinese patients.  相似文献   
10.
Expression of beta-2-microglobulin by nasopharyngeal carcinoma.   总被引:1,自引:0,他引:1  
Serum beta-2-microglobulin (beta 2M) levels of 274 Chinese patients with different stages of nasopharyngeal carcinoma at presentation and that of 35 patients who developed distant metastases post-treatment were assayed. beta 2M level was found to increase with advancing stage of disease, with statistically significant differences among early-stage, advanced-stage, and metastatic disease. Elevated pre-treatment beta 2M levels were expressed more frequently by tumours with lower degree of histological differentiation. The sensitivity of serum beta 2M for diagnosis of nasopharyngeal carcinoma, however, is low.  相似文献   
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