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1.
The phosphodiesterase-5 (PDE-5) inhibitor, sildenafil, has been reported to produce sustained pulmonary vasodilatation in patients with pulmonary hypertension (PH). Recently, vardenafil, a more potent and selective PDE-5 inhibitor than sildenafil, has been approved for the treatment of erectile dysfunction. However, the long-term effects of oral vardenafil in patients with PH are unknown. We studied five consecutive patients with PH; one with primary pulmonary hypertension, two with chronic pulmonary thromboembolism, one with Eisenmenger syndrome (ventricular septal defect) and one with secondary pulmonary hypertension after a ventricular septal defect closure operation. In an acute hemodynamic trial, vardenafil (5 mg) significantly decreased both the pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) with an increase in cardiac output. In a chronic hemodynamic trial, the maintenance dose of vardenafil (10 to 15 mg) for 3 months significantly decreased the PVR, but not the SVR, with a 20.7% reduction of the PVR/ SVR ratio. Plasma brain natriuretic peptide (BNP) levels were also significantly decreased after 3 months. This pilot study demonstrates that long-term oral vardenafil therapy may be a safe and effective treatment for patients with PH.  相似文献   
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A 44-year-old women developed marked myopathy one year earlier, when she was treated with intravenous prednisolone for acute severe exacerbation of ulcerative colitis. When she was admitted to our hospital for another severe exacerbation, intravenous cyclosporine A was administered as monotherapy because she could not tolerate corticosteroid. The treatment was successful and she obtained complete remission. Cyclosporine A monotherapy is considered to be a valuable alternative to proctocolectomy for severe ulcerative colitis patients who cannot tolerate corticosteroid.  相似文献   
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It has been well documented that piriform sinus fistulae often cause suppurative thyroditis; however, when a piriform sinus fistula does not present this symptom, making a correct diagnosis is very difficult. We have experienced 11 cases of a piriform sinus fistula. The conventional operational approach was performed in the initial eight patients, among which there were four recurrences in two patients. Therefore, a new operational approach was introduced for the three most recent cases and one recurrent case. First, the existence of the internal orifice of the fistula is confirmed with a laryngoscope, after which a transverse incision on the neck is made and the abscess dissected. The side wall of the piriform sinus is then opened with the help of a laryngoscope and the bottom part of the mucosa of the sinus transected with the internal orifice of the fistula, after which the fistula is removed en bloc with the bottom part of the sinus and abscess cavity. Using this operation, we experienced no complications and there has been no recurrence so far.This paper was presented at the 23rd Annual Meeting of Pacific Association of Pediatric Surgeons, June 1990 in Kona, Hawaii.  相似文献   
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As a model system for mucocutaneous lymph node syndrome (MCLS), we have advocated and used mice which had been rendered tolerant to Streptococcus pyogenes-associated antigens by neonatal infection with group A fteta-hemolytic streptococci, because these mice have shown a variety of peculiar bioimmunological characteristics bearing a striking resemblance to those of MCLS patients. The results of our current investigations reaffirmed the reliability of the animal model by indicating that mice subjected to neonatal infection with 5. pyogenes , or inoculation with streptococcal pyrogenic exotoxin (SPE) in Freund's adjuvant, were perfect counterparts of patients with MCLS on account of their platelet activation and hyperaggregability in response to provocative treatment, which are familiar findings in this disease.  相似文献   
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BACKGROUND: Although it has been reported that ghost cells are present in odontomas, the generation mechanism of these cells is unclear. To evaluate the presence of ghost cells and involvement of the Wnt signaling pathway, we examined the expression of hard keratins, beta-catenin and Lef-1 in odontomas. METHODS: Sixty-nine cases of odontoma were examined immunohistochemically with the use of antibodies against human hair proteins, beta-catenin and Lef-1. RESULTS: Expression of hard keratins was found only in the cytoplasm of ghost cells in 46 (66.7%) of the 69 odontomas. Compound odontomas (78.8%) showed a higher incidence of ghost cells than complex odontomas (29.4%). Histopathologically, ghost cells were found within odontogenic epithelium adjacent to immature enamel and in the centre of Liesegang-ring-like calcified materials. Expression of beta-catenin and Lef-1 was observed in the cytoplasm and nucleus of odontogenic epithelial cells adjacent to the ghost cells in immature odontomas. CONCLUSION: These findings suggest that odontoma is a hard keratin-expressing tumor-like lesion, and that the Wnt signaling pathway may be involved in the formation of ghost cells in odontomas.  相似文献   
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Skin and soft tissue defects are sometimes problematic especially when the defects large, contaminated, irradiated, or poor blood supplied. The human mesenchymal stem cells (hMSCs) are proliferated upon basic fibroblast growth factor (bFGF) stimuli in vitro and in vivo. In this experiment, the skin and soft tissue defects are investigated if the wounds are able to be reepithelialized or accelerated by hMSCs, bFGF and porcine‐derived bilayered skin template.
1.5 × 1.5 cm2 nude rat skin and soft tissue defects including panniculus carnosus are excised and 1 × 106 hMSCs and various doses of bFGF (1–100 μg) applied. Before and after normal reepithelialization, the tissues are tested for protein expressions by immunohistochemistry and Western blotting.
The wound sizes are significantly decreased at day 7 with hMSCs with 1, 10, or 100 μg bFGF compared to hMSCs‐alone or medium‐only. All the wounds healed by day 42. 42 Kda and 38 Kda human‐derived pancytokeratin expressions, which do not cross‐react with murine antigens, by Western blotting significantly augmented by 10 μg bFGF compared to hMSCs‐alone. The epidermal immunolocalizations such as integrin α3 and SKALP (Skin‐derived Anti Leukoproteinase) are greatly elevated in time and dose‐dependent manner. Human pan‐cytokeratin expressions are immunoreactive even at day 42.
These data suggest the skin and soft tissue wound healing is accelerated by hMSCs together with bFGF, partly by means of differentiation of hMSCs toward epidermal components.  相似文献   
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Abstract: A 63-year-old man was hospitalized because of jaundice and anorexia. An upper gastrointestinal series and hypotonic duodenography revealed circumferential sclerosis and stenosis of the duodenal wall. Endoscopic examination disclosed an ulcer, the upper margin of which was located at the papilla of Vater. The papilla was situated in the base of the ulcer. Endoscopic retrograde cholangiopancreatography disclosed mild dilatation of the common bile, intrahepatic bile and pancreatic ducts, but with neither severe stenosis nor occlusion. Nevertheless, there was some degree of circumferential compression and mild stenosis of the terminal portions of the bile and pancreatic ducts, as potential causes of obstructive jaundice in this patient. Computed tomographic examination of the abdomen revealed a tumorous lesion at the duodenal bulb. Because malignancy in the duodenum could not be ruled out, a pancreatoduodenectomy was performed. Histopathological examination showed a postbulbar duodenal ulcer, associated with inflammation of the papillary orifice and fibrosis of the region near the papilla. There was no evidence of a tumorous lesion. In this case, a postbulbar duodenal ulcer may have caused obstructive jaundice.  相似文献   
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