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A 78-year-old woman was admitted to our hospital because of tarry stools. A gastric stromal tumor with liver metastasis was diagnosed. Treatment with imatinib mesilate was begun in a dose of 400 mg daily. After 1 month, the primary tumor showed a partial response; the response of the liver metastasis was stable disease. However, grade 2 edema, leukocytopenia, and anemia developed, and the dose of imatinib mesilate was reduced to 200 mg daily. The adverse reactions resolved promptly, and a partial response of both the primary tumor and liver metastasis to imatinib mesilate has been maintained for 28 months. Strategies for lowering the dose of imatinib mesilate are reviewed.  相似文献   
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CT in evaluation of the circle of Willis   总被引:1,自引:0,他引:1  
Summary The method of visualizing the circle of Willis intentionally on contrast-enhanced CT scan was studied. The incidence of circle of Willis in our series was 86%. Only mild side effects were observed, in 7.5% of cases. CT of 60 proven cerebral aneurysms were reviewed and aneurysm was detected in 57%. This method has the potential to be a noninvasive screening procedure for evaluation of suspected cerebral aneurysm, as well as evaluation of marked arteriosclerosis, occlusion of major arteries, and mass effect of parasellar tumors.  相似文献   
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A silver colloid staining technique for identifying nucleolar organizer region-associated proteins (Ag-NORs) was applied to 17 primary gliomas and 16 meningiomas. These comprised 8 glioblastomas, one pleomorphic xanthoastrocytoma, 8 benign astrocytoma, 10 nonrecurrent meningiomas and 6 recurrent meningiomas, in which the mean number of Ag-NORs' per nuclei, were 3.37, 2.34, 2.57, 2.16 and 2.80 respectively, identifying significant differences among these groups. Ag-NORs of four giant cell glioblastomas showed low numbers of Ag-NORs, suggesting better prognosis. In spite of the time consuming and complicated counting method Ag-NORs is reproductive and useful as a tool for estimating the proliferating potential of various brain tumors, and appears to widely applicable in clinical laboratories.  相似文献   
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Ras‐family GTPases regulate a wide variety of cellular functions including cell growth and differentiation. Di‐Ras, which belongs to a distinct subfamily of Ras‐family GTPases, is expressed predominantly in brain, but the role of Di‐Ras in nervous systems remains totally unknown. Here, we report that the Caenorhabditis elegans Di‐Ras homologue drn‐1 is expressed specifically in neuronal cells and involved in synaptic function at neuromuscular junctions. Loss of function of drn‐1 conferred resistance to the acetylcholinesterase inhibitor aldicarb and partially suppressed the aldicarb‐hypersensitive phenotypes of heterotrimeric G‐protein mutants, in which acetylcholine release is up‐regulated. drn‐1 mutants displayed no apparent defects in the axonal distribution of the membrane‐bound second messenger diacylglycerol (DAG), which is a key stimulator of acetylcholine release. Finally, we have identified EPAC‐1, a C. elegans Epac homologue, as a binding partner for DRN‐1. Deletion mutants of epac‐1 displayed an aldicarb‐resistant phenotype as drn‐1 mutants. Genetic analysis of drn‐1 and epac‐1 showed that they acted in the same pathway to control acetylcholine release. Furthermore, DRN‐1 and EPAC‐1 were co‐immunoprecipitated. These findings suggest that DRN‐1 may function cooperatively with EPAC‐1 to modulate synaptic activity in C. elegans.  相似文献   
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Background

Resected specimens of superficial squamous cell carcinoma of the esophagus (SSCCE) underwent D2-40 immunostaining to accurately assess lymphatic tumor emboli (LY) and to analyze correlations between LY and lymph node metastasis (N). This present study was designed to determine the accuracy of LY grade for predicting the risk of N.

Materials and methods

We studied 75 patients with SSCCE who underwent surgical resection of their tumors. Resected specimens were sliced into continuous sections at 5?mm intervals. Intramucosal cancers are classified into three groups (m1, m2, m3), and submucosal cancers are also divided into three groups (sm1, sm2, sm3). The numbers of LY present in lymphatic ducts on D2-40 immunostaining, venous tumor emboli (V) on CD34 immunostaining, and lymphatic tumor emboli (ly) and V on hematoxylin-eosin staining (HE) and elastica van Gieson staining (EVG) were counted for each case. The presence of lymphatic tumor emboli was graded according to the total number of LY per case as follows: 0, LY0; 1 to 2, LY1; 3 to 9, LY2; and 10 or more, LY3.

Results

All m1 and m2 cases were LY? and N? Lymphatic tumor emboli were present in 54% of m3 cases, 70% of sm1 cases, 54% of sm2 cases, and 75% of sm3 cases. Determination of N was positive in 18% of m3 cases, 47% of sm1 cases, 36% of sm2 cases, and 62% of sm3 cases. The frequency of LY significantly correlated with the number of N (p?Conclusions Evaluation of lymphatic invasion on the basis of LY is more accurate for the prediction of N than conventional techniques, and LY grade strongly correlates with N. In patients with SSCCE, mucosal cancers (m1, m2, and m3) and submucosal cancers with a depth of invasion of ??200???m from the lower margin of the muscularis mucosae on endoscopic mucosal resection have a low risk of N if the number of LY is 0. Endoscopic mucosal resection alone can provide good treatment outcomes in such patients.  相似文献   
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