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Abstract: This paper dicusses the use of esophageal dilatation with a Rigiflex TTS balloon. This method was used 45 times on 11 patients affected by anastomotic or a severe grade peptic esophageal stenosis. Fluoroscopic guidance was used in 36 procedures (80%) without effecting the mean duration of the treatment (12 minutes). The results were considered satisfactory when these goals had been achieved: a) dilatation of the stenosis over 15 mm; b) a dysphagia free-time of more than 6 months. A satisfactory result was achieved in 10 patients (90.9%), without deaths and major complications. 5 patients received 1 dilatation and the other 5 needed, 3-3-4-7–11 procedures respectively to obtain a satisfactory result. On these basis we consider that its great efficacy, security and tolerability depend on the following characteristics of the Rigiflex TTS balloon: 1) “radial” dilatation; 2) the possibility of introducing the balloon through the operative channel of the fiberscope; 3) direct visualization of the stenosis during dilatation. The following disadvantages with this method are: the absence of a tactile sensation of dilatation and the elevated cost of the instrument. We conclude that the Rigiflex TTS balloon is an important alternative to guide-wire techniques, especially for the treatment of severe esophageal strictures. 相似文献
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Anulus fibrosus in bulging intervertebral disks 总被引:1,自引:0,他引:1
In this investigation the association of radial tears of the anulus fibrosus and bulging of the intervertebral disk was studied. An index of disk bulging was measured in sagittal anatomic sections in 149 lumbar disks from 31 cadavers. The indexes of disk bulging were correlated with stages of disk development and the presence of an annular tear. The largest disk-bulging indexes were always associated with radial tears of the anulus. Eighty-four percent of the disks with radial tears had disk-bulging indexes greater than 2.5 mm. Most normal adult disks had an index of less than 2.5 mm. The results challenge the concept that the anulus fibrosus is intact in bulging disks, although ruptured in herniated disks. 相似文献
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Policosanol is a new cholesterol-lowering drug isolated and purified from sugar-cane wax. which prevents the development of lipofundin-induced lesions and foam-cell formation in New Zealand rabbits and Wistar rats. This study was conducted to examine the effects of policosanol on foam-cell formation in carrageenan-induced granulomas in rats. Eighteen Wistar rats were randomly distributed in three experimental groups which received orally for 20 days Tween 20 H2O as vehicle (control group) or policosanol at 2.5 or 25 mg kg?1. At the 11th day. lipofundin was injected intrapcritoneally for 8 days to induce formation of foam cells in the granuloma. At day 13, carrageenan was injected subcutaneously for granuloma induction and seven days later animals were killed. A significant reduction of the foam-cell formation in granulomas of policosanol-treated rats was observed. It is concluded that policosanol prevents the development of foam cells in carrageenan-induced granulomas (extravascular medium) in rats. 相似文献
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Twelve Sardinian patients affected by histologically defined classic Kaposi's sarcoma (KS) were HLA-A, B, C and DR typed. Compared to 220 age and ethnically matched healthy controls, KS patients showed a significant increase in HLA-DR5 (66.6 vs 23.1%, P less than 0.001) and a considerable decrease in HLA-DR3 (8.3 vs 53.6%, P = 0.0055). No definite association was observed for other HLA antigens. These results confirm the existence of an HLA associated genetic control of KS susceptibility and support the hypothesis that HLA-DR5 plays the role of a predisposition marker while HLA-DR3 bears a genetic resistance to the disease. 相似文献
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Antigenicity and protective effects of type 3 pneumococcal polysaccharide in rats. 总被引:1,自引:1,他引:1
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Total hemolytic complement and C3 levels were found to drop to 6.25% and 50% of preinfection levels, respectively, during trypanosome infections. Chemotherapeutic elimination of the trypanosomes with Berenil led to recovery of preinfection levels within 7 days and 11 days when cattle infected with Trypanosome congolense and Trypanosoma vivax, respectively, were treated 37 days after onset of infection. Recovery was slower in T. vivax-infected cattle treated on day 50. Berenil treatment had no effect on complement levels in control animals. The possible causes and implications of these low complement levels in bovine trypanosomiasis are discussed. 相似文献
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Human microvascular endothelial tissue culture cell model for studying pathogenesis of Brazilian purpuric fever. 总被引:1,自引:2,他引:1
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F D Quinn R S Weyant M J Worley E H White E A Utt E A Ades 《Infection and immunity》1995,63(6):2317-2322
Brazilian purpuric fever (BPF) is a fulminant pediatric disease characterized by fever, with rapid progression to purpura, hypotensive shock, and death. All known BPF cases have been caused by three clones of Haemophilus influenzae biogroup aegyptius and have occurred in either Brazil or Australia. Using an immortalized line of human vascular endothelial cells, we developed an in vitro assay that identifies all known BPF-causing H. influenzae biogroup aegyptius strains (R. S. Weyant, F. D. Quinn, E. A. Utt, M. Worley, V. G. George, F. J. Candal, and E. W. Ades, J. Infect. Dis. 169:430-433, 1994). With multiplicities of infection (MOIs) as low as one bacterium per 1,000 tissue culture cells, BPF-associated strains produce a unique cytotoxic effect in which the tissue culture cells detach and aggregate in large floating masses after 48 h of incubation. In this study, using a BPF-associated strain and a non-BPF-associated control, we demonstrated that strains which produce the cytotoxic phenotype were able to replicate intracellularly whereas non-BPF-associated strains, with MOIs of > or = 1,000 did not replicate and did not produce the phenotype. We also showed that this phenotype is not caused by the activity of an endotoxin or the release of some other compound from the bacterial cell, since neither gamma irradiation-killed whole BPF clone bacteria nor bacterial cell fractions at MOIs of > 1,000 produced the cytotoxic effect. Furthermore, bacteria in numbers equal to MOIs of > 1,000 treated with chloramphenicol did not produce the cytotoxic phenotype, suggesting a requirement for bacterial protein synthesis. In addition, viable bacteria separated from the tissue culture monolayer by a 0.2-micron-pore-size membrane also failed to produce the phenotype. The ability of the bacterium to invade, replicate, and produce the phenotype appears to be primarily parasite directed since phagocytosis, pinocytosis, and eukaryotic protein synthesis inhibitors, including cycloheximide, cytochalasin D, and methylamine, had no effect on the ability of the bacterium to invade and cause a cytotoxic response. Understanding the basic mechanisms involved in this tissue-destructive process should enhance our knowledge of the general pathogenesis of BPF. 相似文献