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排序方式: 共有843条查询结果,搜索用时 15 毫秒
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   
2.
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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A hepatoprotector of phospholipid nature eplir extracted from silt mud was shown to prevent like essentiale in CCl4-hepatitis in rats the development of the liver parenchyma necroses, to promote the maintenance of the normal activity of enzymes in hepatocytes, to stabilize lysosomes, to stimulate the antitoxic and excretory functions of the liver, to reduce hyperfermentemia. The mechanism of action of eplir is determined by the antioxidant properties, a decrease of lysophosphatide formation and the inclusion of phosphatidylcholine in membranes.  相似文献   
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Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 23, No. 8, pp. 925–929, August, 1989.  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   
10.
A single injection (200 mg/kg, intraperitoneally) or a course of injections (100 mg/kg subcutaneously, daily for 10 days) of lithium chloride given to rats had no significant effect on the content of catecholamines and dihydroxyphenylalanine in the brain stem 1, and 4 h after the injections. In experiments on rabbits the compound (100 mg/kg, intravenously) increased the noradrenalin concentration in the thalamus, hypothalamus, reticular formation, and caudate nucleus. An increase in the dopamine content in the caudate nucleus was accompanied by a simultaneous decrease in its concentration in the thalamus, hypothalamus, reticular formation, amygdala, and hippocampus.  相似文献   
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