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There is a pressing need for a simple non-invasive test of exocrine pancreatic function for use in children. The pancreolauryl test has been modified by the addition of a second marker (mannitol) to achieve a single day test without the need for two timed urine collections. Six healthy subjects and nine patients with cystic fibrosis were studied. Fluorescein, fluorescein dilaurate, and mannitol were taken by mouth, alone or in combinations, followed by 10 hour urine collections in two hourly aliquots to study the comparative pharmacokinetics of these markers. Urinary fluorescein was determined spectrophotometrically and urinary mannitol enzymatically. When fluorescein dilaurate and mannitol were taken together and the results expressed as ratios of percentage fluorescein to percentage mannitol recovery (F:M ratio) (mean (SD)) there was clear discrimination between healthy subjects and those with cystic fibrosis regardless of enzyme replacement treatment (57.3 (18.2) v 3.4 (1.4) v 3.2 (1.6) respectively). The differences in F:M ratios reached statistical significance in urinary aliquots collected between two and eight hours after marker ingestion. This single day tubeless test will greatly simplify the investigation of the child with suspected exocrine pancreatic dysfunction. 相似文献
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Twenty-five patients with known or suspected evidence of venous disease based on results of computed tomography, angiography, or ultrasound were imaged with magnetic resonance (MR) to determine the MR characterization of venous abnormalities. MR findings were proved by laparotomy or autopsy in 18 of 25 cases. In seven of 25 patients in whom only biopsy was performed, the MR findings were correlated with findings from other radiologic tests. On MR, the inferior vena cava (IVC), portal vein, and their major tributaries were seen in all but two cases. In those two, identification of collaterals led to the correct diagnosis of splenic vein thrombosis in one case and left renal vein thrombosis in another. MR imaging helped identify intraluminal thrombi in the IVC (12 of 12 cases), portal vein (two of two cases), renal veins (seven of seven cases), superior mesenteric vein (one case), and iliac veins (seven of seven cases). Intraluminal signal intensity secondary to slow blood flow seen in five patients was always differentiated from the thrombus. MR imaging helped identify correctly the nature of the thrombus in 11 of 16 patients. In five patients, the differentiation between tumor thrombus and blood clot thrombus was not possible. Involvement of the IVC wall by tumor was seen in four cases. MR imaging also accurately depicted slow flow in obstructed or constricted veins; encasement, compression, or displacement of veins without intraluminal occlusions; and the presence of venous collaterals. The MR imaging evaluation of venous abnormalities is accurate, easily performed, and will probably become an important application. 相似文献
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Agent Orange exposure and its long-term health consequences on Vietnam veterans have been widely discussed in the past few years. Myriad physical and mental disabilities have been studied with regard to exposure to various herbicides. The number of persons potentially exposed is large, since 2.4-2.8 million U.S. military personnel served in Vietnam. A case-control study was undertaken to determine if persons who served in the U.S. military in Vietnam have either cardiovascular or pulmonary effects that can be demonstrated on long-term follow-up chest radiographs. Information regarding military service in Vietnam was obtained from interviews and, in some cases, review of military records. Vietnam veterans did not have an increased prevalence of abnormalities on follow-up chest radiographs. A subset of Vietnam veterans who had greater estimated opportunities for Agent Orange exposure also did not appear to be at greater risk than the control population. 相似文献