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51.
Edelman RR; Hahn PF; Buxton R; Wittenberg J; Ferrucci JT; Saini S; Brady TJ 《Radiology》1986,161(1):125-131
The authors demonstrate that it is possible to obtain highly T1-weighted images of the abdomen using a suspended respiration partial saturation (SRPS) method in a breath-holding interval. T2*-weighted images, which reflect tissue T2 as well as variations in the static magnetic field, can also be rapidly obtained. The authors studied five healthy subjects and 19 patients with a variety of liver abnormalities, including benign and malignant hepatic neoplasms, fatty liver infiltration, ascites, and hematoma. On T1-weighted multisection acquisitions, the entire liver can be screened for mass lesions in a single 20-second breath-holding interval. Phase-contrast SRPS images are sensitive to fatty infiltration of the liver. SRPS images are more sensitive to variations in magnetic susceptibility than spin-echo images are, which has been proved to be of value in the detection of hemorrhage. With continued pulse sequence development and clinical study, this method has the potential to become the method of choice for evaluation of the upper abdomen. 相似文献
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BACKGROUND: The effect of prestorage filtration on the quality of apheresis platelet concentrates stored for transfusion is undetermined. STUDY DESIGN AND METHODS: Investigation of 11 plateletpheresis components used a concurrent paired-study design. On the day of collection, each component was equally divided into two suspensions; one half was filtered, and the other half was not. Each suspension was stored for 5 days. In vitro testing was performed on the day of collection (Day 0) for cell counts and on Day 5 for measurements of lactate, glucose, blood gases, pH, platelet ATP, hypotonic stress ratio, extent of shape change in response to ADP, tissue necrosis factor alpha, interleukin 8, interleukin 1 alpha, interleukin 1 beta, interleukin 6, and platelet surface glycoproteins by flow cytometry. At the end of the 5-day period, a sample was taken from each of the two suspensions, radiolabeled with either 51Cr or 111In, and transfused concurrently. Posttransfusion samples were drawn for measurements of recovery and platelet survival and for functional assessment of the ex vivo ability of the circulating radiolabeled platelets to aggregate in response to ADP. RESULTS: The apheresis component had a mean platelet yield of 3.2 +/? 0.4 × 10(11) and a white cell yield ranging from 1 × 10(5) to 1 × 10(8), with a median of 2 × 10(7). Filtration resulted in a platelet loss of approximately 10 percent and a variable 2 to 3 log10 reduction in white cell content. No significant differences between filtered and unfiltered suspensions in paired t tests that would likely have an impact on platelet quality were observed in the in vitro tests. The in vivo recovery and survival were highly similar and not statistically different in filtered and unfiltered paired suspensions: the mean difference was 1.2 +/? 4.0 percent for recovery and 7.0 +/? 15 hours for survival. The functional assessment by aggregation to ADP showed no difference between filtered and unfiltered suspensions. A small decrease in tumor necrosis factor alpha and interleukin 8 was evident in the filtered suspension as compared to levels in the unfiltered suspensions. CONCLUSION: Prestorage white cell reduction in apheresis components resulted in WBC reduction by several log10 with no evident adverse effect on platelet viability or function. 相似文献
53.
Henry DA; Corcoran HL; Lewis TD; Barnhart GR; Szentpetery S; Lower RR 《Radiology》1989,170(2):343-350
As cardiac transplantation has become widely available, computed tomography (CT) of the chest has played a useful role in the examination of patients after heart transplantation. To determine anatomic features related to the procedure, the authors evaluated 59 scans in 46 patients who had undergone orthotopic cardiac transplantation. Aortic anastomosis (seen in 98% of scans) and altered spacing between the great vessels (83%) proved to be the most common and most reliable findings. Other features including atrial anastomosis, high main pulmonary artery segment, remnant superior vena cava, and cardiac reorientation were also seen. Accurate interpretation of adenopathy, mediastinal abscess, and pericardial effusion will be enhanced in these patients through a better understanding of the cardiovascular-pericardial complex, which is afforded by CT. 相似文献
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Percutaneous gastrostomy for enteral feeding 总被引:1,自引:0,他引:1
Over a period of 18 months, percutaneous nonendoscopic gastrostomy using the Seldinger technique was successfully performed in 32 adults for enteral feeding. There were no deaths or major morbidity related to the procedure. Three patients died of existing disease within 30 days; one had peritoneal irritation following dislodgement of the catheter two days after the procedure but responded to conservative treatment with antibiotics alone. The authors conclude that this procedure is simple and safe and represents the preferred method of gastrostomy for enteral feeding. 相似文献
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