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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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Benzo[a]pyrene diol epoxide I modification of DNA in human skin xenografts   总被引:1,自引:0,他引:1  
Human skin xenografts were established on the subscapular area of skin of nude (nu/nu NIH-Swiss background) mice. When treated with benzo[a]pyrene diol epoxide I (BPDE I), specific carcinogen-DNA adducts were formed. Separation and identification of these adducts by the 32P-postlabeling technique indicated that the 7R- and 7S-BPDE I-dpGp adducts were the major adducts. Xenografts pretreated with either allantoin or anthralin showed an increase in the major 7R- and 7S-BPDE I adducts compared to only BPDE I treatment. Likewise, we observed an increase in the quantity of different minor adducts. The ratios between the minor and major adducts in the pretreated grafts remained consistent with the ratio in the grafts treated with BPDE I only. We conclude that these modulators induce cells in the xenograft to enter S phase of the cell cycle. Moreover, we observed that these compounds altered the quantity of the minor carcinogen-DNA adducts without altering the overall ratios between the major 7R- and 7S-BPDE I-dpGp adducts and the minor carcinogen-DNA adducts.  相似文献   
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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   
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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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DNA isolated from chondrosarcoma cells effectively transformedNIH-3T3 cells and human foreskin fibroblasts. The transfectedNIH-3T3 cells, directly implanted three or four passages later,formed progressively growing tumors ( 2.0 cm in diameter) subcutaneouslyin nude mice. No metastasis was evident upon pathological examinationof the tumor bearing mice. Transfected human foreskin fibroblaststhat exhibited anchorage independent growth formed only smalltumors in nude mice (<0.6 cm in diameter). The transfectedhuman cells which exhibited anchorage independent growth reactedwith the monoclonal antibody 345.134S, specific for an epitopeexpressed by human sarcoma cells. The transfected NIH-3T3 cellsdid not exhibit reactivity with the same monoclonal antibody.Southern blot analysis of the DNA prepared from the transfectedNIH-3T3 cells, that developed as a progressively growing tumorin a nude mouse, revealed the presence of human repetitive DNAsequences.  相似文献   
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