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Malakoplakia in the gastrointestinal tract is rare in healthy young people without underlying disease. Sufficient tissue is required for accurate diagnosis. We describe a malakoplakia that developed in a healthy young woman and was treated by endoscopic mucosal resection (EMR). A 40‐year‐old woman with a history of taking oral contraceptives until one year earlier was referred to our hospital with anal bleeding and constipation. A colonoscopy carried out at our another hospital 18 months earlier disclosed no abnormal findings. Colonoscopy at presentation revealed a yellowish‐white tumor, 5 mm in diameter, in the rectum. The lesion was slightly protruded and had a smooth flat surface, without erosion or ulceration. EMR was carried out for a definitive diagnosis. Histopathological examination showed that the tumor contained granular histiocytes, positive for CD68 and negative forcytokeratin (AE1/AE3). Several histiocytes contained intracytoplasmic round bodies (Michaelis–Gutmann bodies), which reacted positively with periodic acid‐Schiff and calcium (Von Kossa) stains. Intracytoplasmic Escherichia coli (von Hansemann bodies) were identified by Giemsa staining. Based on these results, the tumor in the rectum was diagnosed as a malakoplakia. Following EMR, the patient did not receive further treatment for malakoplakia because she had no symptoms associated with malakoplakia. She has been well for more than 9 months, with no symptoms of disease. Awareness of colorectal malakoplakia is important in patients taking steroids, including oral contraceptives.  相似文献   
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Nonspecific vasodilatation during iontophoresis is an important confounding factor in experimental pharmacology. In this investigation, we studied the involvement of sensory nerves and histamine-related reactions in causing nonspecific vasodilatation in a model of anodal and cathodal iontophoresis of sodium chloride. Firstly, we applied a mixture of local anesthetic (EMLA) cream to confirm its suppressive effect on nonspecific vasodilatation and to measure its efficacy in three different dosages (duration: 1, 2, and 3 h). We then investigated the role of histamine in nonspecific vasodilatation by giving an oral antihistamine drug (cetirizine) to subjects who had and had not been given EMLA. We found substantial suppression of the nonspecific vasodilatation in all EMLA-treated groups (all dosages) compared with untreated controls (with suppression rates of 60-65%). Dosage had no significant effect. A further suppression of nonspecific vasodilatation was seen after oral cetirizine during anodal and cathodal iontophoresis in both EMLA-treated and untreated groups. The antihistamine effect was most pronounced during anodal iontophoresis. These results suggest a histaminergic increase in perfusion that may be independent of neurogenic mechanisms and depend on polarity (anode or cathode). Local nerve blocks (EMLA) together with cetirizine may therefore be used to reduce nonspecific vasodilatation in both anodal and cathodal iontophoresis.  相似文献   
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BACKGROUND/AIMS: Helicobacter pylori infection is known to induce gastritis, oxidative stress, and cyclooxygenase (COX)-2 expression in the gastric mucosa. However, the effect of H. pylori infection on remnant gastritis has not been studied. We investigated whether the severity of remnant gastritis and COX-2 expression were affected by H. pylori infection after distal gastrectomy. METHODOLOGY: The study included 97 patients with gastric cancer who underwent curative distal gastrectomy with lymphadenectomy in our department between May 1999 and April 2001. All patients underwent endoscopic examination 2 weeks before and 12 weeks after surgery. The presence of H. pylori infection was determined by urease activity, hematoxylin-eosin staining, and immunochemical staining. Histologic remnant gastritis was graded based on the degree of neutrophil infiltration using the updated Sydney System. COX-2 expression was estimated immunohistochemically. RESULTS: Both the degree of neutrophil infiltration and the level of COX-2 expression were significantly higher in patients with than without H. pylori (p<0.05). There was a significant correlation between the degree of neutrophil infiltration and the degree of COX-2 expression (p<0.001). CONCLUSIONS: H. pylori eradication may become a treatment for preventing both remnant gastritis as well as remnant gastric carcinoma after distal gastrectomy.  相似文献   
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Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic dodecapeptide (SIKPSAYLPLRF-NH(2)) that directly inhibits gonadotropin synthesis and release from quail pituitary. The action of GnIH is mediated by a novel G-protein coupled receptor. This gonadotropin-inhibitory system may be widespread in vertebrates, at least birds and mammals. In these higher vertebrates, histological evidence suggests contact of GnIH immunoreactive axon terminals with GnRH neurons, thus indicating direct regulation of GnRH neuronal activity by GnIH. In this study we investigated the interaction of GnIH and GnRH-I and -II neurons in European starling (Sturnus vulgaris) brain. Cloned starling GnIH precursor cDNA encoded three peptides that possess characteristic LPXRF-amide (X = L or Q) motifs at the C termini. Starling GnIH was further identified as SIKPFANLPLRF-NH(2) by mass spectrometry combined with immunoaffinity purification. GnIH neurons, identified by in situ hybridization and immunocytochemistry (ICC), were clustered in the hypothalamic paraventricular nucleus. GnIH immunoreactive fiber terminals were present in the external layer of the median eminence in addition to the preoptic area and midbrain, where GnRH-I and GnRH-II neuronal cell bodies exist, respectively. GnIH axon terminals on GnRH-I and -II neurons were shown by GnIH and GnRH double-label ICC. Furthermore, the expression of starling GnIH receptor mRNA was identified in both GnRH-I and GnRH-II neurons by in situ hybridization combined with GnRH ICC. The cellular localization of GnIH receptor has not previously been identified in any vertebrate brain. Thus, GnIH may regulate reproduction of vertebrates by directly modulating GnRH-I and GnRH-II neuronal activity, in addition to influencing the pituitary gland.  相似文献   
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Microscopic polyangiitis associated with diffuse panbronchiolitis   总被引:1,自引:0,他引:1  
There are several case reports of systemic vasculitis associated with chronic suppurative lung diseases. We describe a 46-year-old female, previously diagnosed as having diffuse panbronchiolitis (DPB), presenting with hemosputum and dyspnea. Her serum titer of MPO-ANCA was positive together with a high titer of BPI-ANCA. Chest X-ray and chest CT scan showed pulmonary hemorrhage, and the renal biopsy specimen revealed necrotizing, crescentic glomerulonephritis. She was diagnosed as having ANCA-associated vasculitis, and more specifically, microscopic polyangiitis accompanied by DPB. She was treated with methylprednisolone pulse therapy, followed by intravenous cyclophosphamide. This case suggested a possible association with chronic bacterial infection, which may play a role in the pathogenesis of ANCA-associated vasculitis.  相似文献   
30.
Two cases of recurrent pneumonia due to Chlamydia pneumoniae are described. C. pneumoniae was continuously detected from the nasopharynx in both patients by the polymerase chain reaction and/or culture even with appropriate antibiotic therapy during the first episode. After eradication of C. pneumoniae with long-term macrolide therapy, the respiratory symptoms of both patients completely disappeared and no relapse was observed. These data indicate that new treatment strategies may be necessary to eradicate the organism in patients prone to persistent infection.  相似文献   
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