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41.
Administration of an elemental diet to rats given methotrexate (MTX), 20 mg/kg intraperitoneally (ip), results in 100% mortality from severe enterocolitis. Previous studies indicate that glutamine (GLN), which is not present in elemental diets, is the preferred oxidative substrate for the gut and may facilitate intestinal recovery after injury. This study investigated the effects of a glutamine-supplemented elemental diet (GLN-ED) on nutritional status, intestinal morphometry, bacterial translocation and survival in this lethal model of intestinal injury. Three experiments were performed. In the first experiment, rats received an intragastric elemental diet supplemented with either 2% GLN or an equivalent amount of glycine (Control). After 4 days animals received either MTX, 20 mg/kg ip, or saline ip and were killed 3 days later. The GLN-ED resulted in significantly decreased weight loss, improved nitrogen retention, and increased mucosal weight, protein, and DNA content of the jejunum and colon. In the second experiment rats were assigned to diet as in the first experiment, but all animals received MTX. Control diet animals died within 120 hrs of MTX administration. The GLN-ED group had significantly longer survival time and decreased mortality. In the third experiment animals were assigned to diet and MTX as in the first experiment. Ninety-six hrs later aortic blood cultures revealed enteric bacteremia in animals administered MTX. GLN-ED resulted in a significant reduction in the incidence of bacteremia. These experiments showed that a GLN-ED significantly improved nutritional status, decreased intestinal injury, decreased bacterial translocation, and resulted in improved survival in a lethal model of enterocolitis.  相似文献   
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Objectives: To investigate the effect of the type instrumentation used and the age and gender characteristics of patients on postoperative haemorrhage rates following tonsil and adenoid surgery. Design: A retrospective analysis of 13 593 procedures was performed from The Patient Episode Database for Wales between 1 January 1999 and 31 March 2004. Setting: National health policy changes created four periods of different instrument usage (reusable, single‐use with diathermy, single‐use alone, specified single‐use with diathermy). These and the age and gender distribution of the patients were examined against four categories of postoperative haemorrhage. Main outcome measures: Postoperative haemorrhage rates were expressed as the number of complications per operations performed. Primary postoperative haemorrhage that occurred during the initial admission either required a return to theatre [R1] or was managed conservatively [N1]; secondary postoperative haemorrhage that required a return to hospital either returned to theatre [R2] or was managed conservatively [N2], were compared. Results: Primary haemorrhage with return to theatre doubled, from the baseline rate with reusable instruments, from 0.6% (CI 0.5–0.8) to 1.2% (CI 0.7–1.9) when single‐use instruments were introduced and remained high at 1.4% (CI 0.9–2.1) after the withdrawal of single‐use diathermy. This haemorrhage rate returned to the baseline rate (0.6% CI 0.3–1.0) when specified single‐use instruments were introduced. None of the other haemorrhage rates changed significantly throughout the four observation periods. Adenotonsillectomy and tonsillectomy patients have different age and gender patterns. In a univariate analysis, males over the age of 12 years were twice as likely to have haemorrhage with return to theatre than girls of the same age, 3.8% (CI 3.0–4.7) versus 1.7% (CI 1.4–2.1). Conclusions: A significant rise in serious postoperative primary haemorrhage but not secondary haemorrhage was seen following the initial introduction of single‐use instruments that reverted to baseline with the introduction of specified single‐use instruments. Diathermy does not appear to have affected the haemorrhage rates. There is a distinct age and gender pattern for tonsil and adenoid surgery and risk of postoperative haemorrhage. The use of arbitrary divisions of age may be misleading in studies that examine post‐tonsillectomy haemorrhage.  相似文献   
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In this European study, the phenotype in 68 patients, homozygous or compound heterozygous for the G85E mutation, was investigated. Each index case was compared with two cystic fibrosis (CF) patients from the same clinic, matched for age and sex: one with pancreatic sufficiency (PS) and one with pancreatic insufficiency (PI). When comparing 31 G85E/F508del and F508del/F508del patients, there were no differences in median age at diagnosis, mean sweat chloride value, most recent weight for height, most recent forced expiratory volume in one second % predicted, prevalence of chronic Pseudomonas aeruginosa colonisation and typical CF complications. However, PI was less frequent in the G85E/F508del group. Comparison of 55 G85E patients (with second mutation known and not classified as mild) with PS controls (n=44) showed that the G85E patients had a significantly higher sweat chloride, more often failure to thrive at diagnosis, higher prevalence of PI, worse current weight for height, higher prevalence of chronic P. aeruginosa colonisation and liver cirrhosis. Pulse-chase experiments revealed that G85E cystic fibrosis transmembrane conductance regulator failed to mature on a M470 as well as on a V470 background. Therefore, G85E is a class II mutation. Although there is variability in its clinical presentation, G85E mutation results in a severe phenotype.  相似文献   
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The history of prealbumin dates back to the early forties and may be divided into three parts, based on a chronological and functional approach. The first part--the discovery and the identification of prealbumin--was essentially based on classical protein chemistry methods. The second--the demonstration of prealbumin as a thyroid hormone-binding protein (thyroxine-binding prealbumin)--has greatly benefited from isotopic techniques. The third one--establishing prealbumin as a nutritional marker--was a result of field studies on nutrition. The discovery of the role of prealbumin in retinol binding led to a change in its name, prealbumin becoming transthyretin. Finally, structural studies and mutation analysis of transthyretin in patients with amyloid neuropathy have opened a new area of research.  相似文献   
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The effects of 2,4-Dichlorophenoxyacetic acid on the growth rate, chemical composition, 14C-2,4-dichlorophenoxyacetic acid and 45Ca2+ uptake by Rhizobium sp. M 4 able to nodulate Arachis hypogaea were determined. Cellular growth was diminished by the presence of 10?3 M 2,4-dichlorophenoxyacetic acid in the medium. Alterations in cellular chemical composition, in 14C-2,4-dichlorophenoxyacetic acid and in 45Ca2+ uptake were found.  相似文献   
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Eighty-two consecutive aphakic or pseudophakic retinal detachments were treated by buckling and vitrectomy procedures. Functional results (86.6%) and the incidence of proliferative vitreoretinopathy (11%) were comparable with reports of cases treated by the classic method.Presented at the 1984 meeting of the Club Jules Gonin in Lausanne, Switzerland  相似文献   
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