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The principles of infusion manometry in the measurement of lower esophageal sphincter (LES) pressure were laid down in the mid-1960s by L.D. Harris and his coworkers. Dodds and his colleagues were largely responsible for the improvements and advent of the low-compliance manometry. Using side-hole manometry, it is possible to detect accurate LES pressure that correlates with the strength of the antireflux barrier. The LES pressure as measured by the side-hole manometry, shows respiration-induced pressure oscillations. These pressure oscillations were initially thought to be due to the influence of abdominal and thoracic pressures on the LES. However, it was later pointed out that these pressure oscillations were due to the relative motion of the point pressure sensor (side hole of the manometric catheter) and the LES during respiration. Recent studies suggest that active contraction of the crural diaphragm during inspiration is responsible for the pressure oscillations observed in the cat LES pressure tracings. The use of the sleeve device in the measurement of LES pressure during contraction of the diaphragm has been described recently. Using the principles of manometry and sleeve device, it is now possible to identify two lower esophageal sphincters: the smooth muscle LES, traditionally known as the LES, and crural diaphragm, which we have referred to as the external lower esophageal sphincter. The purpose of the following paper is to summarize the general principles of the infusion manometry in the measurement of intraluminal pressure, specifically the LES pressure. The recently developed technique of detection of the sphincteric function of the crural diaphragm by the sleeve device will be discussed. In the last paragraph the limitations of manometry in detection of the muscular contractile activity are described.  相似文献   
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Duodenogastric reflux (DGR) has been implicated in several disease processes. The present study was carried out to document the incidence and evaluate the clinical significance of DGR after choledochoduodenostomy (CDD). A total of 13 patients who had undergone cholecystectomy with a standard side-to-side CDD for choledocholithiasis or chronic pancreatitis were studied by symptom evaluation, scintigraphy, endoscopy, and gastric mucosal histology at least 6 months after surgery. The scintigraphic findings were then compared with those of 10 patients who had undergone cholecystectomy alone. Only two patients (15%) had mild dyspeptic symptoms. The incidence of DGR after CDD was 69% compared to 20% in the cholecystectomy alone group (P < 0.05). In the majority of patients the DGR was only mild to moderate and the severity correlated well with the degree of endoscopic gastritis, but not with the clinical symptoms or histological findings. These results indicate that while CDD is associated with a high incidence of DGR, its occurrence does not produce significant clinical symptoms.  相似文献   
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Diagnostic and therapeutic upper gastrointestinal endoscopy was carried out among 200 children. The procedure proved useful in detecting causes of various upper gastrointestinal problems especially hematemesis and dysphagia. It was also helpful in early detection of esophageal varices in children with suspected portal hypertension. Duodenal biopsies could be obtained in all children being investigated for chronic diarrhea and proved helpful in diagnosing three cases of celiac disease. Fiberoptic endoscopy has a large role to play in pediatric practice and is largely a safe procedure.  相似文献   
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Classical and anaplastic seminoma: difference in survival   总被引:1,自引:0,他引:1  
Bobba  VS; Mittal  BB; Hoover  SV; Kepka  A 《Radiology》1988,167(3):849-852
Classical and anaplastic seminoma are traditionally treated with radiation therapy and are said to have the same prognosis. A retrospective study was undertaken of 90 seminoma patients treated with radiation therapy between 1961 and 1985. The classical group consisted of 71 patients of whom 50 had stage I and 21 had stage II disease. The anaplastic group consisted of 19 patients of whom ten had stage I and nine had stage II disease. The median follow-up time was 64 months for the entire group. The 10-year relapse-free survival rate for the classical group was 94% and for the anaplastic group was 70% (P less than .05). For patients with classical stage I disease, the relapse-free actuarial survival rate was 98%; for patients with anaplastic stage I disease, it was 64% (P less than .02). For the classical stage II disease group, the relapse-free actuarial survival rate was 84% and for the anaplastic stage II disease group, 75% (P less than .70). Four patients in the classical group (6%) had relapses; of these, one patient had local recurrence of tumor, and three had distant metastases. In the anaplastic group, four patients (21%) had relapses; two patients had local recurrence of tumor, and two had distant metastases. Therefore the data suggest a difference in survival and relapse rates between classical and anaplastic seminoma.  相似文献   
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BACKGROUND: Septic shock is an important cause of death in pediatric intensive care units. Initial evaluations have shown that vasopressin may have a role in catecholamine refractory shock in adults. It is important to determine whether children with septic shock have deficiency of vasopressin. This will help in defining the role of vasopressin in septic shock. DESIGN: Prospective cohort study. SETTING: Pediatric intensive care unit of a tertiary care hospital in north India. PATIENTS: Patients were children with septic shock, and controls were children with sepsis but no shock. STUDY DESIGN: Vasopressin levels in plasma were determined by enzyme-linked immunosorbent assay for children with septic shock at diagnosis (baseline) and thereafter at 24, 48, and 96 hrs to determine the time trends. The baseline vasopressin values for children with septic shock were compared with those for children without shock. RESULTS: The median (95% confidence interval) vasopressin level at baseline in children with septic shock was 116 (63.3-130.7) pg/mL, and in children with sepsis but no shock it was 106 (61.7-131.77) pg/mL. The median value for survivors was 76 (44.6-130.9) pg/mL, and for nonsurvivors, 118 (81.7-259) pg/mL (p = .16). The serial values also did not show any significant changes; the values at 24 hrs (n = 17), 48 hrs (n = 16), and 96 hrs (n = 15) were 105 (76.1-125.9), 105 (41.4-155.5), and 109.5 (54.9-154.8) pg/mL, respectively. CONCLUSIONS: The results of our study suggest that vasopressin levels are elevated in children with septic shock and that serial values up to 96 hrs do not show any decline.  相似文献   
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