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BACKGROUND/AIMS: Catheterization of the femoral vein is a safe and recommended method of temporary access for haemodialysis. In some patients, however, because of the lack of other possibilities, it is necessary to maintain long-term femoral cannulation. The aim of the study was to evaluate the frequency of stenosis after prolonged femoral cannulation. METHODS: The 24 patients incorporated in the study were divided into two groups. Group 1 consisted of 10 end-stage kidney failure patients (four females and six males, aged 32-75 years, average 55.6+/-13.6 years) in whom femoral catheters were maintained for less than 2 weeks (5-14 days, average 9.3+/-3.6 days). Group 2 included 14 chronic haemodialysis patients (six females and eight males aged 23-65 years, average 49.5+/-13.27 years). The time of catheter maintenance ranged from 2 to 16 weeks (average 6.4+/-4.2 weeks). Femoral and iliac vein status was evaluated using magnetic resonance imaging. RESULTS: A feature of venous stenosis of both the femoral and iliac veins was disclosed in four patients in whom femoral cannulation lasted more than 4 weeks. There were no stenoses in group 1. CONCLUSION: Long-term femoral cannulation for more than 4 weeks may be associated with a significant risk of stenosis in the femoral and/or external iliac veins.  相似文献   
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The ionophore X537A induced swelling of isolated rat mast cells parallel to histamine release. Both actions were depressed by extracellular calcium and BSA, temperatures below 37°C, NEM, PMSF, and TTX, and were enhanced by high potassium and pretreatment of the cells with ATP. DSCG, theophylline, and DFP enhanced the histamine release noted after 10 min of incubation without influencing the swelling action of X537A. The swelling action could not be separated from histamine release and it is suggested that it right be inherent in the mechanism of secretion induced by X537A. The present results further distinguish histamine release induced by the two ionophores X537A and A23187.  相似文献   
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BACKGROUND: Intravenous glycoprotein GP IIb/IIIa receptor antagonists administered to patients with acute coronary syndromes limit platelet-dependent thrombus formation and vasoconstriction and lower the complication rate of PCI. The efficacy of glycoprotein IIb/IIIa inhibitors critically depends on appropriate suppression of platelet aggregation. A growing body of evidence indicates that regimen of tirofiban used in several recent trials may be suboptimal. We investigated if a novel regimen of dosage of tirofiban administered to patients with acute myocardial infarction with ST elevation (STEMI) before primary angioplasty is safe, feasible and whether such treatment improves coronary flow in infarct-related artery. METHODS: It was an open-label, non-randomized, prospective observational study. 253 consecutive patients with STEMI, qualified to PCI were included. 104 of patients (group 1) received heparin plus tirofiban at a novel regimen (10 microg/kg bolus, followed by 0.4 microg/kg/min for 30 min and then 0.1 microg/kg/min for 12-24 hours) and the remaining 149 of the patients (group 2) received a standard dose of heparin prior to PCI. Bleeding complications were recorded. The primary end point of the study was combined TIMI 1 + 2 + 3 grade flow at the time of first contrast medium injection during angiography for primary PCI. RESULTS: Heparin was administered 50.3 +/- 58.1 minutes (group 1) or 62.3 +/- 67.3 minutes (group 2) ( p = 0.205). Tirofiban was administered for an average of 14.5 +/- 14.4 minutes before TIMI assessment (group 1). In patients treated with heparin + tirofiban the rate of combined TIMI 1 + 2 + 3 coronary flow was higher (38.4% vs. 24.8%, p = 0.020) as compared to patients treated with heparin alone. The difference in the rate of TIMI > or = 2 coronary blood flow between the groups 1 and 2 (24.0% vs. 20.1%) has not reached statistical significance ( p = 0.459). At the same time the significant difference in the rate of TIMI 1 coronary blood flow between the groups 1 and 2 was noted (14.4 vs. 4.7%, p = 0.007). In hospital mortality in the groups 1 and 2 was similar (5.3 vs. 4.8%, p = 0.838). Significant difference was noted between the groups 1 and 2 with regard to minor bleeding complications (17.3 vs. 8.7%, p = 0.041). CONCLUSION: In patients undergoing primary angioplasty for acute myocardial infarction the novel regimen of tirofiban is well tolerated and feasible, and is associated with improvement in coronary blood flow in the infarct related artery. Larger studies assessing the effects of tirofiban on clinical outcomes of patients with AMI undergoing primary angioplasty seem worthwhile.  相似文献   
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Adrenal epithelioid angiosarcoma is an extremely rare tumor. Even if such tumors are very aggressive, a long survival may occasionally be observed after an adrenal ectomy. A 70-year-old woman suffering from persistent right flank pain showed a 5-cm right adrenal mass plus a 2-cm liver mass at the radiologic workup, and both were suspected of being malignant. No adrenal hypersecretion was demonstrated. During an explorative median laparotomy the right adrenal gland with the whole periadrenal tissue and locoregional lymph nodes was removed. A histological examination revealed an adrenal angiosarcoma. The resection margin was tumor-free with no lymph node infiltration. The liver mass turned out to be a cistobiliary adenoma. Since no distant metastases were observed, no adjuvant chemotherapy was performed. After an 18-month follow-up the patient is still well with no sign of a relapse. When this rare adrenal tumor is encountered and curative treatment is attempted initially extensive surgical procedures are essential. Received: April 16, 2001 / Accepted: November 20, 2001  相似文献   
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Conclusions The results indicate that X537A exerts its histamine-releasing action only in the presence of monovalent cations. The release is not dependent on either extra- or intracellular calcium, in fact extracellular calcium depressed the release. The finding that the release occurred faster in a potassium medium indicates that high potassium increased the permeability of the plasma membrane for X537A or that X537A carries potassium more efficiently over the cell membrane as compared to sodium, in spite of the finding that the affinity of X537A is of the same order for both cations [5]. According to the latter possiblity, monovalent cations would accumulate in the cell and be available for exchange with histamine bound to the granular matrix. Furthermore, the observation that lack of cellular metabolic energy slows down the release process might indicate that metabolic energy influences the penetration of X537A at limiting concentrations. The slow release of histamine induced by X537A in comparison to many calcium- and energy-dependent releasing agents further indicates a different type of mechanism for release.  相似文献   
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Adrenalectomy represents the gold standard treatment for hyperfunctioning adrenal incidentaloma. In cases of silent adrenal masses, on the other hand, the surgical removal of an adrenocortical cancer entails the sacrifice of a large number of safe benign masses, and in most cases surgery is therefore unjustified. The aim of this paper was to clarify the surgical indications for adrenal incidentaloma by reviewing our experience in comparison with the main reference literature. Over the period from 1995 to 2001 we managed 40 cases of incidentaloma. US and CT abdominal scans, adrenal scintigraphy and biochemical tests were performed on an outpatient basis. Seven pre-Cushing syndromes were removed. Ten incidentalomas measured 4 cm or more in diameter: 5 of these were operated on and in 5 cases surgery was not feasible or was refused. Only one malignant mass was detected (an angiosarcoma). Four postoperative minimal complications (18.7%) were observed. The follow-up (median: 48 months) was uneventful. The surgical approach was traditional in 11 cases and laparoscopic in 1 case. Surgery should be considered mandatory in cases of hyperfunctioning adrenal masses in the presence of suspect radiological evidence, in cases of discordant CT and scintigraphy findings and when the maximum diameter is 4 cm or more.  相似文献   
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