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91.
92.
To evaluate the effects of erythromycin on antroduodenal motility in children with chronic functional gastrointestinal symptoms, we studied 35 consecutive subjects referred for diagnostic motility studies. We recorded fasting motility for >4 hr, then infused in random order either 1 or 3 mg/kg erythromycin intravenously over 1 hr and continued the study for another hour. Erythromycin induced phase III in 18 of 20 children who had phase III during fasting compared to only one of 15 who did not (P<0.001). The antral motility index increased after erythromycin (1596±323 vs 436±242 mm Hg/30 min before erythromycin,P<0.005) but the duodenal motility index did not change. The antral motility index was greater in children receiving 3 mg/kg than in those receiving 1 mg/kg (1968±391 vs 1226±285 mm Hg/30 min,P<0.01), but duodenal motility indices did not differ. Only one child receiving the lower dose erythromycin complained of abdominal pain, nausea, or vomiting vs 9 of 19 the children receiving the higher dose (P<0.02). In summary, in children with chronic functional gastrointestinal disorders, erythromycin rarely induced phase III in patients who did not have it during fasting. When different doses erythromycin are compared, 1 and 3 mg/kg are equally efficacious in inducing phase III episodes; the lower dose is associated with fewer side effects and the higher dose produces a higher antral motility index.  相似文献   
93.
94.
We experienced two cases of adenocarcinoma coexisting with a hyperplastic polyp arising from Helicobacter pylori-negative normal gastric mucosa. The first case was of a 59-year-old man. Esophagogastroduodenoscopy revealed a protruding lesion measuring 4 mm in diameter on the greater curvature of the middle gastric body. The second case was of a 47-year-old man. Esophagogastroduodenoscopy showed a protruding lesion measuring 5 mm located at the greater curvature of the upper gastric body. The absence of atrophic changes in the entire gastric mucosa was confirmed endoscopically in both cases. Multiple H. pylori tests were all negative. Endoscopically, these protruding lesions appeared as reddish, semipedunculated polyps. Hyperplastic polyps were suspected based on white light endoscopic findings. Magnified endoscopy with narrow band imaging could not predict the coexistence of cancer. However, histopathological examination of the resected specimen revealed focal cancer at the surface of the gastric hyperplastic polyps. Considering the possibility that cancer may be coexisting in polyps, when reddish polyps are detected in H. pylori-negative normal gastric mucosa, it is important to perform a biopsy, or a careful follow-up endoscopy.  相似文献   
95.
We investigated the possible involvement of the upper alimentary tract in vincristine (VCR)- induced dysmotility. Gastric contractions were recorded by a strain-gauge force transducer in conscious rats. Rats were injected with various doses of VCR followed by continuous recording for 12 hr. Additionally, 3-hr recordings to study the later effects were performed one and three days after injection. Gastric motility was dose-dependently increased by VCR. Post- versus preinjection motility index (MI; area under contraction waves) ratios were 0.78 ± 0.12 for saline and 1.95 ± 0.21 for VCR at 0.75 mg/kg. This increase in MI was completely inhibited by atropine and hexamethonium. MI one day after injection of VCR (0.75 mg/kg) was significantly less than in control (0.32 ± 0.10 vs 0.92 ± 0.24, respectively). The decrease was reversed by acetylcholine. In conclusion, VCR first increased gastric motility, and this was followed by a gradual decrease in conscious rats. These alterations may involve a presynaptic cholinergic pathway.  相似文献   
96.

Objective  

We analyzed the database of the Japanese nationwide inflammatory bowel disease (IBD) registry, which was started in 1975, to characterize basic epidemiological and clinical features of childhood IBD, comparing them to those in adults.  相似文献   
97.
98.
Molecular cloning and characterization of porcine Mx2 gene   总被引:1,自引:0,他引:1  
Mx, an interferon-inducible protein, is found in various vertebrates and confers resistance to several RNA viruses. At least two Mx proteins occur in vertebrates, and these proteins are key components of innate defense against viral infection. In mice and humans, the two Mx genes have different antiviral activities. Both Mx1 and Mx2 have also been detected in pigs, although only a partial sequence of porcine Mx2 has been reported, and there is no information on its antiviral activity. Here, we report the structure of the intact porcine Mx2 gene having an open reading frame of 2136 bp. We also determined the sequence of the genomic region containing the entire porcine Mx2 gene in addition to Mx1 gene. A weak constitutive expression of porcine Mx2 mRNA and endogenous Mx2 protein was observed in interferon-untreated cells. Porcine endogenous Mx2 protein showed nuclear localization. Furthermore, assays using NIH3T3 cells transfected with Mx genes showed that porcine Mx2 possessed antiviral activity against influenza, although this activity was lower than that of human MxA. This report is the first to describe the intact porcine Mx2 gene, which is a functional gene that may play a key role in the clearance of viruses in pigs.  相似文献   
99.
A 2 month old boy with Kawasaki disease developed the rare complication of abdominal aortic aneurysm (AAA). He was followed up over 7 years by ultrasonography (2D-ECHO) with and without Doppler flow evaluation, angiography and computed tomography. Calcification was noted 33 months after the onset of the disease but the aneurysm did not decrease in size. 2D-ECHO was adequate for evaluating the size of an aneurysm, but did not show thrombus formation or calcification. Doppler flow studies did not show abnormally high blood flow velocities either at the inflow or outlet of aneurysms, which are indicative of stenosis. On the other hand an abdominal aortogram provided information regarding the luminal shape and abnormalities in flow pattern suggestive of thrombus formation. Fluoroscopy cannot demonstrate calcification in the early stages. Computed tomography (CT) was the imaging method of choice for the evaluation of obstructive or calcific changes; an organizing thrombus was clearly demonstrated and early detection of calcification was possible.  相似文献   
100.
Measuring antral crosssectional area by ultrasonography can be an ideal way to evaluate intragastric milk volume in infants. Technical details, however, remain to be established before its clinical application. We investigated the effects of posture and ultrasonographic plane on the correlation between milk volume and antral cross-sectional area. After gastric aspiration through a nasogastric tube, healthy newborns were fed 0, 10, 20, and 40 ml of milk cumulatively, and antral cross-sectional area was measured in either upright, sitting, or right lateral position. To determine the best sonographic plane, subjects were put in the right lateral position and antral cross-sectional area was measured in the plane of the aorta and either the superior mesenteric artery, the superior mesenteric vein, the midline of the abdominal surface, 1 cm right of midline, or 2 cm right of midline. The results showed that antral cross-sectional area reflects intragastric milk volume most accurately, with minimal gas interference when measured in the right lateral position. The area correlates well with milk volume in the plane of the aorta and either the superior mesenteric artery, the superior mesenteric vein, or the midline. Next, we studied the effect of intragastric gas on the antral cross-sectional area in subjects who were given 40 ml of milk followed by an injection of air. More than 20 ml of intragastric gas increases antral cross-sectional area significantly. Ultrasonographic evaluation of intragastric volume requires attention to the above factors.  相似文献   
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