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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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This is a case report of a very rare combination of congenital aganglionosis of the intestine (Hirschsprung’s disease) and congenital central hypoventilation syndrome-CCHS- (Ondine’s curse). The combination is also called Haddad syndrome. In about 50% of the cases of CCHS there is associated Hirschsprung’s disease. There are only about 48 cases reported worldwide. The disease has a very high mortality especially in the settings of a developing country.  相似文献   
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An Integrated Vector Management (IVM) strategy was implemented from 1981 to 1985 in one part of Pondicherry, South India, for the control of the bancroftian filariasis vector Culex quinquefasciatus (the IVM area). The rest of the town (the comparison area) received the conventional larvicidal input. After 1985 both the areas were managed conventionally. The switch to conventional strategy resulted in an increase of vector density in both areas. The microfilaraemia prevalence in humans showed a general decline (P less than 0.05) from 1986 to 1989 only in the IVM area whereas its intensity did not change significantly in either area. While the age-specific rate of gain of infection was generally unchanged in the IVM area, an increase in all age classes was observed after 1985 in the comparison area, where the Annual Transmission Index was high during the previous years. In both areas the rate of loss of infection increased during 1986-9 compared to 1981-6. The results suggest that 3 years is too short a period to relate the changes in entomological parameters to those in the microfilaraemia status of the population.  相似文献   
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An oral load of 20 mg/kg galactose produces significant changes in the 31P magnetic resonance spectrum of the liver of a galactosemic patient. The peak at 5.2 ppm (which includes inorganic phosphate and galactose-1-phosphate) increased on two occasions to about twice its original size 60 min after galactose administration. An oral load of 10 mg/kg galactose given to a second patient produced no discernible changes at 30 min. We have also used an animal model of galactose intolerance, in which galactose metabolism in rats was blocked by the acute administration of ethanol. Studies in vivo and in vitro showed that the increase in the peak at 5.2 ppm was largely due to galactose-1-phosphate. We have shown in this preliminary study that small amounts of galactose can produce significant elevation of hepatic galactose-1-phosphate, which can be detected by 31P magnetic resonance spectroscopy.  相似文献   
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