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701.
Aim To determine the usefulness of endoscopically-delivered small intestinal submucosa (SIS) as a scaffold in enhancing the lower oesophageal sphincter (LOS) pressures. Methods Six dogs were endoscopically injected - four with the SIS and two with its glycerin carrier. Manometry was performed prior to injection and every four weeks post-op. Results Adequate and site correct injections were made in four dogs. In one dog, significant augmentation of pressures were obtained at four weeks. None had significant changes in pressure at eight weeks, differences in length at either four or eight weeks or significant differences in the thickness of the examined layers. Four of the six had capillary cushions on pathological examination. The dog injected with the carrier had a loose and disorganised collection, while the others were well organised. Conclusion SIS is a biologically compatible material. Lack of an animal model for gastro-oesophageal reflux disease (GORD) makes determining the ability of injections of SIS to combat reflux problematic.  相似文献   
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Whole-body echo-planar MR imaging at 0.5 T   总被引:2,自引:0,他引:2  
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705.
Low-dose flying spot digital radiography of the chest: sensitivity studies   总被引:1,自引:0,他引:1  
Standard film examinations of the chest were compared with low-dose flying spot digital radiographic examinations obtained with a prototype unit in 174 patients. Analysis of pooled data from a double-blind study of 120 patients showed that film was more sensitive than digital images in the detection of pulmonary parenchymal abnormalities, that is, abnormal opacities, atelectasis, scar, and interstitial lung disease (P less than .05). Analysis of pooled data from a side-by-side study of 54 patients showed that the digital images were more sensitive than film in the detection of normal mediastinal and pleural soft-tissue contours, including the azygoesophageal recess, paraspinal line, and vertebral disk spaces (P less than .05). However, film was more sensitive than digital images in the detection of abnormalities of the lung, including scar, interstitial lung disease, septal lines, and the presence of vascular catheters (P less than .05). These findings suggest that low-dose flying spot digital radiography of the chest, as performed with this specific prototype unit, is not adequate to replace film in the detection of abnormalities of the lung parenchyma.  相似文献   
706.
Benson  M; Bree  RL; Schwab  RE; Ouimette  M 《Radiology》1985,155(2):443-444
Abdominal CT scans were reviewed in a series of 53 patients who had abdominal pain without objective physical, radiographic, or laboratory abnormalities. Forty patients presented with abdominal pain alone, while the remaining patients had abdominal pain associated with nausea, vomiting, or mild weight loss. Abdominal CT scans in all patients were interpreted as normal. In all but one patient, the final diagnosis was an insignificant benign condition. One patient had a pancreatic carcinoma discovered at surgery one month after the CT scan was obtained. The patients were followed up for 6 to 12 months to confirm absence of significant disease. Our analysis suggests a very low yield from abdominal CT in patients with abdominal pain and no other objective findings.  相似文献   
707.
Bloom  SM; Philipps  E; Paul  RE  Jr 《Radiology》1986,161(2):549-550
The posteriorly directed duodenal bulb can be difficult to demonstrate because of the overlapping gastric antrum. A technique is described for displacing the antrum from the bulb while simultaneously distending the barium-coated duodenal bulb with air.  相似文献   
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