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21.
One hundred and seven consecutive patients presenting with significant peptic ulcer haemorrhage were randomised to endoscopic injection with 3-10 ml of 1:100,000 adrenaline (55 patients, group 1) or to a combination of adrenaline and 5% ethanolamine (52 patients, group 2). All had major stigmata of haemorrhage and endoscopic injection was undertaken by a single endoscopist. The groups were well matched with regard to risk factors. Rebleeding occurred in eight of the group 1 patients and seven in the group 2 patients; surgical operation rates, median blood transfusion requirements, and hospital stay were similar in both groups. The efficacy of either form of injection was similar whether patients presented with active bleeding or a non-bleeding visible vessel. No complications occurred. In patients presenting with significant peptic ulcer bleeding, the addition of a sclerosant confers no advantage over injection with adrenaline alone.  相似文献   
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The fumonisins are inhibitors of de novo sphingolipid biosynthesis in vitro and in vivo and thus possibly interfere with the regulation of cell growth, differentiation, and neoplastic transformation. In addition, the ratio of free sphinganine (Sa) to free sphingosine (So) has been proposed as a marker of exposure for animals or humans consuming feed or food contaminated by these toxins. A method to analyze these sphingolipid bases has been proposed [Merrill et al., 1988: Anal Biochem 171:373-381; Riley et al., 1994a: JAOAC 77:533-540] but involves numerous steps and consequently is not ideally suited to the analysis of large numbers of samples, as is often required in epidemiological studies. A new method was therefore developed for the analysis of the Sa/So ratio in tissues as well as human and rat urine. Briefly, the method involves isolation of exfoliated cells from as little as 0.5 ml of rat urine or 2 ml of human urine followed by a rapid and efficient extraction of sphingolipid bases in ethyl acetate, an optimized derivatization step with o-phthaldialdehyde and a high-pressure liquid chromatography separation on a 250 mm x 4.6 mm. 5 microns Kromasil C18 column, with a 4-step phosphate buffer/methanol gradient. Fluorescence was monitored at 340 nm excitation, 455 nm emission, and retention times for So, Sa, and C-20 Sa were about 11, 14, and 22 min, respectively. The method was adapted to tissue analysis by partially digesting approximately 30 mg tissue with trypsin to permit isolation of a cell pellet before extraction of the sphingolipids as described above. The method was applied to the analysis of So and Sa in urines and tissues of fumonisin B1 (FB1) treated and untreated male BDIV rats. The Sa/So ratio in urine of untreated rats varied from 0.1 to 0.7, and for treated rats (between 1-5 mg FB1/kg body weight daily by gavage), the ratio was between 1.2-10. In kidney, the ratio was 0.1 in control rats and varied from 4 to 10.3 in treated rats. In human urine, measurements could easily be made in 2 ml of urine in females, but in males much larger volumes were required due to the low levels of sphingolipid bases.  相似文献   
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Two cases of adverse reactions to intravesical treatment with bacillus Calmette-Guérin are reported. The first patient presented with a severe suppurating epididymo-orchitis three months after his last treatment. The second patient developed Reiter's disease with arthritis of one knee and conjunctivitis 1 week after the fourth instillation.  相似文献   
25.
The postoperative radiographs of 35 patients who underwent impaction allografting of the proximal femur were reviewed. Of Gruen zones that could be clearly visualized, 39.9% contained areas where cement was absent. Even when an adequate mantle was present, cement voids were commonly seen. These cement mantle deficiencies were confirmed in a series of cadaveric impaction allografting procedures. They appear to be a consequence, at least in part, of an inadequate differential between trial and actual component sizes. Additionally, 4 patients were identified with significant component migration secondary to radiographically visible cement mantle fractures within the first 6 months of surgery. It is concluded that the surgical technique requires modification to ensure a more consistent cement mantle and clinical result.  相似文献   
26.
This review reports the different genetic factors that have been identified either as risk factor for Alzheimer's disease (AD) or directly causing the disease. First are reviewed epidemiological data and biological mechanisms about the apoplipoprotein E gene allele epsilon 4 that is a major risk factor for Alzheimer's disease. The second part describes the mutations responsible for early-onset autosomal dominant AD found in three different genes. The gene located on chromosome 21 encodes the amyloid precusor protein (APP). The presenilin 1 and presenilin 2 genes, located on chromosome 14 and 1 respectively, encode not yet known membrane proteins.  相似文献   
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Gene therapy has the potential to provide cancer treatments based on novel mechanisms of action with potentially low toxicities. This therapy may provide more effective control of loco-regional recurrence in diseases such as non-small cell lung cancer (NSCLC), as well as systemic control of micrometastases. Despite current limitations, retroviral and adenoviral vectors can in certain circumstances provide an effective means of delivering therapeutic genes to tumour cells. Although multiple genes are involved in the process of carcinogenesis, mutations of the p53 gene are the most frequent abnormality identified in human tumours. Pre-clinical studies both in vitro and in vivo have shown that restoration of p53 function can induce apoptosis in cancer cells. Phase I clinical trials now show that p53 gene replacement therapy is feasible and safe using both retroviral and adenoviral vectors, and that it induces tumour regression in patients with advanced NSCLC and recurrent head and neck cancer. Other pre-clinical studies indicate that gene therapy may have useful synergy with cytotoxic and radiation therapy. This paper describes the different gene therapy strategies under investigation and the pre-clinical data that provides a rationale for the gene replacement approach, reviews clinical trial data and presents novel ideas for improving current vectors and gene delivery to tumours.  相似文献   
29.
The aims of this study were to establish a working rabbit heart model of regional myocardial ischaemia in which electrophysiologic parameters and arrhythmogenesis could be correlated and to explore the mechanisms underlying the antiarrhythmic activity of lignocaine. Monophasic action-potential duration (MAPD90), effective refractory period (ERP), and conduction delay were measured at three ventricular sites in isolated hearts paced at 3.3 Hz. The hearts were treated before and throughout 30 min of ischaemia and 15 min of reperfusion with a vehicle or 20 microM lignocaine. In both groups, ischaemia produced a similar shortening in MAPD90. Lignocaine decreased ERP shortening during ischaemia from -56+/-4 to -32+/-6 ms. An ischaemia-induced increase in conduction delay was greater in the lignocaine than the control group (49+/-7 vs. 11+/-2 ms). Ischaemia-induced dispersion of repolarisation was reduced by lignocaine from 66+/-4 to 32+/-7 ms, and dispersion of refractoriness was decreased from 57+/-6 to 16+/-3 ms. Lignocaine decreased inducibility of ventricular fibrillation (VF) during ischaemia from 86 to 25%. We conclude that, in this model, the antiarrhythmic activity of lignocaine during regional ischaemia is associated with an increase in ischaemia-induced conduction delay and reduced dispersion of repolarisation and refractoriness.  相似文献   
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