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PURPOSE: This study was designed to investigate colonic spike bursts regarding 1) their migration behavior, 2) their pressure correlates, and 3) comparing colonic short spike bursts with spike bursts from migrating myoelectric complex from the small bowel. METHODS: Rectosigmoid electromyography and manometry were recorded simultaneously in seven normal volunteers and electromyography alone in five others during two hours of fasting and for two hours after one 2,100-kJ meal. One patient with an ileostomy was also studied by the same method to record the migrating myoelectric complex from the terminal ileum during fasting. RESULTS: Three kinds of spike bursts were observed in the pelvic colon: rhythmic short spike bursts, migrating long spike bursts, and nonmigrating long spike bursts. The meal significantly increased the number of migrating and nonmigrating long spike bursts (from 25 to 38.7 percent of the recording time; P <0.01). These bursts of potentials showed a peak 15 minutes after the meal, which may be caused by the gastrocolic reflex. Migrating long spike bursts started anywhere along the rectosigmoid and migrated from there aborad 82 percent of the time and orad or in both directions in 10 or 7 percent of the time, respectively. They originated pressure waves 99 percent of the time. Short spike bursts were more frequent before the meal (15.1 percent before and 9.6 percent after the meal), but the difference was not significant; they neither propagated nor initiated pressure waves detected by the miniballoon. CONCLUSIONS: Migrating long spike bursts were the only potentials that migrated, sometimes for short distances. Short spike bursts are a different phenomenon from the small-bowel migrating myoelectric complex because they do not migrate; they can occur during the postprandial period and never originated intraluminal pressure waves.Supported by a grant from the Instituto Nacional de Investigação Científica, Proc. DBI-22086.Presented at the meeting of the Portuguese Congress of Gastrenterology, Vila Moura, Portugal, June 2 to 5, 1993.  相似文献   
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Ureteral hernia is uncommon and usually misdiagnosed. From an anatomic point of view, we can distinguish between two uretero-inguinal hernias: intraperitoneal and extraperitoneal. Ureter inguinal hernias are nearly always indirect. This kind of hernia can include the ureter alone or, frequently, other abdominal sliding organs within the hernia sac (bladder, bowel tracts, etc.). Kidneys and urinary tracts present normal anatomic conformation, although renal ptosis may be found. As of July 2004, 139 cases of ureteral hernia had been described in the literature. Here we report a case of inguino-scrotal herniation of double district ureter and review the current literature to analyze the main clinical characteristics of this pathology and to establish pitfalls.  相似文献   
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BACKGROUND: Homocysteine (Hcy) is an independent risk factor for cardiovascular disease (CVD). Individuals with Type 1 and Type 2 diabetes are more susceptible to the effects of homocysteine than non-diabetic subjects. The interaction between homocysteine-thiolactone (Hcy-thiolactone), a reactive product of Hcy, and low-density lipoproteins (LDL) induces the formation of homocystamide-LDL adducts (Hcy-LDL) and it has been suggested that homocysteinylation could increase atherogenicity of lipoproteins. AIM: The aim of the study was to compare the effect of in vitro homocysteinylation of LDL isolated from healthy control subjects (C-LDL) and from Type 1 diabetic patients (DM-LDL) and to investigate the effect of homocysteinylated LDL (Hcy-C-LDL and Hcy-DM-LDL) on peroxynitrite production of endothelial cells. METHODS: The in vitro homocysteinylation of LDL isolated from control (n = 12) and DM subjects (n = 12) was carried out by incubating lipoproteins with Hcy-thiolactone. The reaction was verified by quantifying the increase in sulphydryl groups (-SH groups) in Hcy-LDL with respect to control LDL. Control and homocysteinylated LDL were incubated with human aortic endothelial cells (HAEC) in culture. Peroxynitrite production in cells treated in different experimental conditions was assayed by a fluorimetric method. RESULTS: The increase in -SH groups after incubation with homocysteine was greater in LDL from diabetic subjects compared with LDL from control subjects (P < 0.001). In addition, peroxynitrite production from HAEC incubated with Hcy-LDL from diabetic patients was greater than after incubation with Hcy-LDL from control subjects and untreated LDL from diabetic patients (P < 0.001). CONCLUSIONS: These results show that LDL from diabetic patients is more susceptible to in vitro homocysteinylation than LDL from non-diabetic individuals and demonstrate that the compositional changes in Hcy-LDL from diabetic subjects have cytotoxic effects on human endothelial cells.  相似文献   
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Schistosoma mansoni infection, both in humans and in animal models, is known to induce granulomas in the liver and intestine. It has also been reported that in humans the eggs of this parasite can reach the brain, causing psychiatric and neuropathological disorders. Whether this also occurs in rodents is unknown. To answer this question, mice were infected with this parasite and the central nervous system (CNS) examined at various time intervals. The results show that schistosomiasis induced granulomas in several regions of the CNS and increased nerve growth factor (NGF) levels in the cortex, hypothalamus and brain stem, but not in the hippocampus. The infection also caused paw hyperalgesia, as determined by the hot-plate test, and a local increase in NGF, but not in substance P. These findings indicate that the murine model of infection can be used for studying mechanisms leading to human neuroschistosomiasis and suggest that the neuropathological disorders and the sensory deficits observed in human schistosomiasis are associated with impaired levels of NGF in the peripheral and central nervous system. Received: 18 January 1996 / Revised, accepted: 16 April 1996  相似文献   
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Twenty-seven opening-wedge osteotomies of the proximal part of the tibia were performed in twenty-five patients who had genu recurvatum. In sixteen knees, the genu recurvatum was due entirely to osseous deformity. In the remaining eleven knees, it was due to a combination of osseous and soft-tissue deformity; in five, the deformity was predominantly osseous and in six, primarily in the soft tissues (the ligaments and capsule). The average age of the patients was twenty-three years (range, fifteen to fifty-four years). The osteotomy was proximal to the tibial tuberosity in twenty-two knees. In eighteen of these knees, the tuberosity was detached with its patellar ligament and then reattached to the proximal part of the tibia over the block of bone in the opened wedge; in the remaining four knees, the tibial tuberosity was not detached. The osteotomy was distal to the tuberosity in five knees. The patients were followed for an average of 14.5 years (range, three to thirty years). Of the eighteen knees in which the osteotomy had been proximal to the tibial tuberosity and the tuberosity had been detached and then reattached, nine (50 per cent) had a result that was excellent; five (28 per cent), good; and four (22 per cent), fair. Of the four knees in which the operation had been proximal to but without detachment of the tuberosity, one had a result that was excellent; two, good; and one, fair. Of the five knees in which the osteotomy was distal to the tibial tuberosity, one had a result that was good; three, fair; and one, poor. Of the twenty-one knees in which the deformity was entirely or predominantly osseous, eighteen (86 per cent) had an excellent or good result. None of the six knees in which the deformity was predominantly in the soft tissues had an excellent or good result. Patients in whom the deformity was not primarily osseous, and those in whom the operation was distal to the tibial tubercle, were much more likely to have a fair or poor result.  相似文献   
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The specific humoral immune response against Epstein-Barr virus (EBV) antigens in patients with nasopharyngeal carcinoma (NPC) was compared to that of patients with infectious mononucleosis (IM) and other EBV-seropositive subjects using immunoblotting technique. Almost all sera from E,BV serologically associated NPC reacted reproducibly with a major group of polypeptides (four to six) of early antigen (EA) complex with molecular weights ranging from 50 kD to 58 kD, and with some additional polypeptides. Sera from IM-patients reproducibly recognized only one polypeptide of 50 kD belonging to the major group of polypeptides of EA-complex. Sera from patients with other types of head and neck cancer and relatively high levels of IgG antibody against viral capsid antigen (VCA) and EA did not react reproducibly with any of the EBV-associated proteins.  相似文献   
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The effect of tritoqualine on seasonal allergic rhinitis caused by grass pollen was compared to that of dexchlorpheniramine maleate (DCPM) in 21 patients randomly allocated into two parallel groups. There were rapid improvements of all symptoms considered after treatment with either tritoqualine or DCPM. A significant reduction of plasma histamine concentrations was observed during the treatment with tritoqualine whereas no modification occurred with DCPM. Finally, it was shown that tritoqualine did not modify reaction times to visual and auditive stimuli whereas DCPM induced a significant slowing-down of the reaction time to visual stimuli. From this pilot study tritoqualine appears to have the same efficacy for the treatment of seasonal allergic rhinitis as classic anti-H1 antihistamines, but without central nervous system side-effects.  相似文献   
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Twenty patients with AIDS who had intracranial lesions underwent both brain biopsy and cerebro-spinal fluid (CSF) examination to compare histological diagnosis with the polymerase chain reaction (CSF-PCR) for the identification of infectious agents. CSF-PCR was performed for herpes simplex virus, varicella zoster virus, cytomegalovirus (CMV), JC virus (JCV), Epstein-Barr virus (EBV), Toxoplasma gondii and Mycobacterium tuberculosis. A definitive diagnosis was obtained by brain biopsy in 14 patients (2 with astrocytoma, 12 with brain infection). CSF-PCR was positive for EBV DNA in 3 of 3 cases of primary cerebral lymphoma, positive for JCV DNA in 6 of 7 biopsy-proven (and one autopsy-proven) cases of progressive multifocal leukoencephalopathy (PML). CSF-PCR was positive for CMV DNA in one biopsy-proven and one autopsy-proven case of CMV encephalitis (the former also had PML) and positive for M. tuberculosis DNA in one case of tuberculous encephalitis. None of the five toxoplasmic encephalitis cases (one definite, four presumptive) were T. gondii DNA positive. There was close correlation between histology and CSF-PCR for CMV encephalitis, PML and PCL. Antitoxoplasma therapy affected the sensitivity of both histological and CSF-PCR methods. Received: 8 November 1995 Received in revised form: 9 July 1996 Accepted: 19 July 1996  相似文献   
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