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1.
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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Abstract  We previously demonstrated that cytomegalovirus (CMV) infection enhanced perivascular inflammation in rat aortic allografts. In this study, we investigated the relationship between the CMV infection load and the magnitude of perivasculitis (chronic rejection) in aortic transplants. Rats received or-thotopic abdominal aortic grafts, different degrees of total body irradiation (TBI) for immunosuppres-sion and CMV inoculation. The spleens of the rats receiving 5 Gy of TBI contained more infectious virus and viral antigens than those of rats receiving 3 Gy of TBI or no TBI. Although the number of inflammatory cells infiltrating the perivascular area was decreased after TBI, CMV infection resulted in increased perivasculitis in rats that received 5 Gy of TBI as compared to non-infected animals. This virus-induced effect was characterized predominantly by an increased T-cell infiltration, including CD4 and CD8 T-cells. It is concluded that an enhanced systemic CMV infection during severe immunosuppressive therapy can accelerate the development of chronic rejection, which seems to be mediated mainly by T-cells.  相似文献   
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The procoagulant response of cytomegalovirus infected endothelial cells.   总被引:6,自引:0,他引:6  
The report describes the effect of an in vitro infection of human umbilical vein endothelial cells with human Cytomegalovirus (CMV). The parameters studied are cellular procoagulant activity, secretion of plasminogen activator inhibitor (PAI-1) and urokinase-type plasminogen activator (u-PA), activation and internalization of factor X and Merocyanine 540 staining. The infection does not result in an increase in PAI-1 and u-PA secretion, but it brings about a procoagulant response, which is relatively rapid compared to the tissue factor mediated response induced by inflammatory mediators. The time course and the coagulation factor dependency suggest a facilitated interaction of coagulation factors on the surface of infected cells. Chromogenic activity measurements after the addition of purified factor X and electron microscopic examination of the cells after addition of colloidal gold-factor X conjugates both point to an internalization of factor X and/or Xa after interaction with the endothelial cell surface. Merocyanine 540 staining suggests that CMV infection leads to membrane perturbations.  相似文献   
5.
Anulus fibrosus in bulging intervertebral disks   总被引:1,自引:0,他引:1  
Yu  SW; Haughton  VM; Sether  LA; Wagner  M 《Radiology》1988,169(3):761-763
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   
6.
Cytomegalovirus infection induces vascular injury in the rat.   总被引:8,自引:0,他引:8  
The role of cytomegalovirus (CMV) in the early development of atherosclerosis was studied in a rat model. Arterial samples derived from virus-infected normo- and hypercholesterolaemic animals were investigated by light microscopy at 1, 4, 8 and 16 weeks post infection. Early atherogenic lesions comparable to those seen in non-infected hypercholesterolaemic rats were found in CMV-infected normocholesterolaemic and hypercholesterolaemic animals, starting at 1 week post infection. The changes consisted of minimal endothelial cell damage, as shown by the en face technique, and a more than 10-fold increase in the number of leukocytes adhering to the aortic intima. The increased adhesion of leukocytes was observed in infected normocholesterolaemic rats but only in the non-infected rats which were hypercholesterolaemic. The infection of hypercholesterolaemic rats did not enhance this effect although it resulted in increased migration of the leukocytes into the subendothelial space. CMV infection of normocholesterolaemic rats induced lipid accumulation in the endothelium. In these animals approximately 1% of the endothelial cells contained lipid at 1 week post infection. In the non-infected hypercholesterol-fed animals 10% of the cells contained lipid. CMV infection in these rats induced an extra increase of the lipid-containing endothelial area. The changes in the CMV infected animals largely corresponded with the intimal injury observed in the hypercholesterolaemic rats. These results support the hypothesis that CMV may be one of the factors involved in atherogenesis.  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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