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1.
OBJECTIVE: Transanal endoscopic microsurgery (TEM) is a minimally invasive technique for excision of selected benign and malignant rectal neoplasms. It is considered a safe and effective treatment but recurrence rates of 1-13% are reported for benign lesions. The aim of this study was to assess risk factors for local recurrence of benign rectal lesions and to evaluate mortality and morbidity following TEM. METHOD: Data were prospectively collected from all patients undergoing TEM for benign adenomas from January 1998 to March 2005. The procedure was performed by a single surgeon and patients were regularly followed up. RESULTS: One hundred and forty-six procedures were included, with a median patient age of 74 years (range 22-92 years). The mean lesion area was 16 cm(2) (range 0.3-150 cm(2)) and the median distance from the dentate line was 9 cm (range 0-17 cm). Immediate complications included bleeding (six) and acute urinary retention (six). There has been one (0.68%) procedure-related death. After a median follow up of 39 months (range 4-89 months) there have been seven recurrences (4.8%), recurring at a mean time of 23.3 months (range 5-48 months). Only microscopic involvement of the circumferential resection margin was found to be significantly associated with recurrence (P = 0.0059). Recurrence was not associated with age, size of lesion, previous treatment, severity of dysplasia or use of the harmonic scalpel. CONCLUSION: TEM is a safe and effective treatment for benign rectal adenomas. Circumferential resection margin involvement is associated with recurrence, which tends to occur late. Therefore extended follow up is recommended. 相似文献
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PURPOSE: Epilepsies in children are complex diseases. Guidelines are needed on the appropriate use of newer versus older anti-epileptic drugs (AEDs). This paper presents an individual patient-sampling model to assess the cost-effectiveness of using newer AEDs as add-on therapy in line with UK prescribing guidance. METHODS: Identification of the relevant parameters and treatment pathways for the model were achieved by a systematic review of the literature and discussions with clinical experts. Data were obtained from the literature and supplemented with data elicited from paediatric neurologists. The model considered paediatric patients over the period of childhood from the age of diagnosis to 18 years. RESULTS: The results suggest that the older and newer AEDs are similar in terms of drug retention rates and the average time in 'good' treatment outcomes. In terms of cost, the results indicate a consistent increase in cost (compared to older AEDs) when all of the newer AEDs are considered. The decision analysis results indicate that there are no important health benefits from the use of newer AEDs when used as add-on therapy. However, the analysis also reveals that the uncertainties in the model are greater than the differences between the drug strategies. CONCLUSIONS: To develop guidelines on the appropriate use of newer AEDs, better information is required from randomised controlled trials as there is insufficient data available in the public domain to accurately estimate the nature of the trade off between older versus newer AEDs. 相似文献
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Orbital volume measured by a low-dose CT scanning technique. 总被引:6,自引:0,他引:6
A method for measuring orbital volume using low-dose CT with contiguous 3 mm transaxial sections is described. The accuracy of the method is 1.6%, as demonstrated by comparing CT volume measurements with those derived directly from alginate impressions and on repeat scanning the precision of the measurement was judged as 1.3%. Within the same individual, the right and left orbital volumes were observed to be within 0.6 cm3 (s.d. +/- 0.33 cm3) of each other. This study demonstrates that low-dose CT scanning is a practical method of determining orbital volume and could be used to advantage in the management of traumatic enophthalmos and blow-out fractures of the orbit. 相似文献
6.
Excretion of phenazopyridine and its metabolites in the urine of humans, rats, mice, and guinea pigs
B H Thomas L W Whitehouse G Solomonraj C J Paul 《Journal of pharmaceutical sciences》1990,79(4):321-325
The metabolism of the urinary tract analgesic phenazopyridine [2,6-diamino-3-(phenylazo)pyridine; PAP] was studied in the urine of humans, rats, mice, and guinea pigs. Urinary excretion was rapid in human and guinea pig, but in the rat and mouse it was slower and there was significant fecal excretion. Metabolism of PAP was extensive in all four species, and there were marked quantitative differences in the routes of metabolism. The extent of azo bond cleavage was high in the mouse and guinea pig, moderate in the rat, and low in humans. Hydroxylation of both the phenyl and pyridyl rings of PAP was observed in all species. In the human, 5-hydroxyl PAP was the major metabolite (48.3% of the dose). It was concluded that there are marked species differences in the metabolism of PAP, and that none of the species studied resembles the human; the rat comes closest, but cannot be considered a particularly good model. 相似文献
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M B Patterson J L Mack M M Neundorfer R J Martin K A Smyth P J Whitehouse 《Alzheimer disease and associated disorders》1992,6(3):145-163
Assessment of activities of daily living (ADL) in Alzheimer disease (AD) is critical in establishing the diagnosis, monitoring disease progression, evaluating the efficacy of treatment interventions, and determining the need for health and social services. The proper method to measure ADL depends on the purposes to which the scale is to be put. Existing ADL scales differ as to the type of behaviors assessed, the nature of the observations made, and the manner in which the observations are quantified. These scales were not specifically designed to evaluate changes in the nature and extent of the broad spectrum of functional difficulties seen in individuals with AD. We describe the Cleveland Scale for Activities of Daily Living (CSADL), an informant-based instrument designed to expand upon the capacity of existing physical and instrumental ADL scales by assessing both premorbid and current component acts (e.g., initiation versus implementation) of daily living functions. 相似文献
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A combination of 65Zn-tracer determinations, oxidative analyses for glycerol, and a bioassay for uncomplexed Zn2+ have shown that: (i) zinc monoglycerolate (ZMG) dissolves in aqueous salt solutions/physiological media by dissociation into zinc ions and glycerol, but the rate and extent of ZMG dissolution depend upon pH, and/or concentration and complexing efficiency of zinc-ligands; (ii) under physiological conditions certain ligands present in skin and blood (e.g. citrate, lactate, albumin, histidine, glutathione and other thiols and, to a lesser extent, amino acids) accelerate ZMG dissolution; and (iii) there is a general correlation between the conditional stability constants (pH 7.3, 25 degrees C) of zinc-ligand complexes and the ability of given ligands to (a) solubilize ZMG in vitro and (b) mask the irritancy of Zn2+ in vivo. These observations indicate a mechanism for the transformation of ZMG applied transdermally or subcutaneously, to bioactive zinc (anti-arthritic nutritional supplement, etc.). 相似文献
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A useful function of any complementary medicine is to supplement some of the benefits from other treatment modalities. In rats, extracts from Indian celery seed and the NZ green-lipped mussel are powerful nutraceuticals that (i) amplify the potency of salicylates and prednisone for treating pre-established chronic inflammation (arthritis, fibrosis) and (ii) reduce the steroid's gastrotoxic and lymphopenic side effects. Such combinations might also be useful for treating inflammatory components of (a) osteoarthritis caused by microcrystalline hydroxyapatite (BCP) and (b) pseudo-gout, associated with calcium pyrophosphate crystals; that are usually refractory to monotherapy. 相似文献