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The evolution of a collagen/vicryl composite membrane designed as a prosthetic material for use in urinary tract surgery is described. The early experiments in which collagen film alone was used to repair experimental ureterotomies are reviewed together with our first experiments with the collagen/vicryl prosthesis in the repair of partial nephrectomies and of full thickness defects created in the urinary bladder of experimental rabbits. These early results led to the preparation of a composite using a more highly purified collagen and employing a method of sterilisation (gamma irradiation) which would be acceptable for regular use in medical products. The results of a further series of partial nephrectomy and full thickness bladder repairs show that irradiation does not compromise the efficacy of the collagen/vicryl composite in vivo.  相似文献   
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The role of Campylobacter pylori gastritis in dyspepsia could be clarified more readily if reliable eradication therapy were available. Antibiotic monotherapy and combined therapy with an antibiotic agent plus a bismuth compound have yielded poor long-term results. In this study, bismuth-tetracycline-metronidazole triple therapy has been used to eradicate C. pylori infection in 100 consecutive patients who were suffering from either a duodenal ulcer or non-ulcer dyspepsia. Examination of a follow-up endoscopic biopsy at eight weeks after treatment showed an eradication rate of C. pylori of 94%. Of 64 patients whose biopsy samples were free of C. pylori infection at eight weeks and who were available for reassessment, 60 (94%) patients had samples that remained free of C. pylori infection on examination of a repeat endoscopic biopsy at 12-37 months (mean, 19.3 months). It is concluded that "triple chemotherapy" can achieve long-term eradication of C. pylori infection effectively in the majority of treated patients and that the recurrence of duodenal ulcers thus may be diminished.  相似文献   
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Carnosine (beta-alanyl-L-histidine), an abundant naturally-occurring dipeptide has been shown to exhibit anti-ageing properties towards cultured cells, possibly due in part to its antioxidant/free radical scavenging abilities. In this paper the results of an investigation on the effects of carnosine, at the physiological concentration of 20 mM, on oxidative DNA damage levels and in vitro lifespan in peripheral blood derived human CD4+ T cell clones are reported. Under the culture conditions used (20% O(2)) long term culture with carnosine resulted in a significant increase in the lifespan of a clone derived from a healthy young subject. No such extension was observed when a T cell clone from a healthy old SENIEUR donor was similarly cultured. Culture with carnosine from the midpoint of each clone's lifespan did not have any effect on longevity, independent of donor age. Oxidative DNA damage levels were measured in the clones at various points in their lifespans. Carnosine acted as a weak antioxidant, with levels of oxidative DNA damage being lower in T cells grown long term in the presence of carnosine. The possibility that carnosine might confer anti-ageing effects to T cells under physiological oxygen tensions would appear to be worthy of further investigation.  相似文献   
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OBJECTIVE: To examine the effect of 17beta-estradiol on the severity of the cardinal signs of PD in postmenopausal women. BACKGROUND: Although the impact of estrogens on the manifestations of PD has not been subjected to rigorous study, their use is generally thought to be associated with a detrimental antidopaminergic effect. METHODS: A double-blind, placebo-controlled, two-arm crossover study of high-dose transdermal 17beta-estradiol was conducted in eight postmenopausal women with mild to moderate PD, all but one of whom exhibited levodopa-induced dyskinesias. Patients were randomized initially to either hormonal treatment or placebo for 2 weeks, followed by a 2-week washout period, and then another 2-week crossover treatment period. Active treatment employed four skin patches each releasing 0.1 mg of estradiol daily, replaced every 2 to 3 days. RESULTS: After 10 days of treatment a significant reduction was observed in the antiparkinsonian threshold dose of IV levodopa. Mean duration and magnitude of the antiparkinsonian response to threshold or high doses of levodopa were unchanged, and dyskinesia scores were unaltered during 17beta-estradiol treatment compared with placebo. No worsening in "on" time or motor ratings with estrogen treatment was documented. CONCLUSIONS: 17beta-estradiol appears to display a slight prodopaminergic (or antiparkinsonian) effect without consistently altering dyskinesias. Standard postmenopausal replacement therapy with transdermal 17beta-estradiol is likely to be well tolerated by many female parkinsonian patients.  相似文献   
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Concise methods for the synthesis of 4‐hydroxy‐3‐[2H3]‐methoxyphenylalanine (3‐O‐[2H3]‐methydopa) and 3‐hydroxy‐4‐[2H3]‐methoxyphenylalanine (4‐O‐[2H3]‐methydopa) are described. The 3‐O‐[2H3]‐methydopa is a valuable internal standard for the tandem MS quantification of 3‐O‐methyldopa, a metabolite of value in the diagnosis of aromatic l‐amino acid decarboxylase (AADC) deficiency. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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BackgroundSmall bowel involvement of Clostridium difficile is increasingly encountered. Data on many management aspects are lacking.AimTo synthesis existing reports and assess the frequency, pathophysiology, outcomes, risk factors, diagnosis and management of C. difficle enteritis.MethodsA systematic review of the literature was conducted to evaluate evidence regarding frequency, pathophysiology, risk factors, optimal diagnosis, management and outcomes for C. difficle enteritis. Three major databases (PubMed, MEDLINE and the Cochrane Library) were searched. The review included original articles reporting C. difficle enteritis from January 1950 to December 2012.ResultsC. difficle enteritis is rare but increasingly encountered. Presentation is variable and distinct predisposing factors include emergency surgery, white race and increased age. Diagnosis generally involves a sensitive but often non specific screening test for C. difficile antigens. Oral metronidazole represents first line therapy and surgery may be required for complications. Outcomes are inconsistent but may be improving.ConclusionsA high index of clinical suspicion, early diagnosis and treatment are vital. Further prospective studies are needed to determine the significance of asymptomatic small bowel C. difficile infections.  相似文献   
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