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BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation.  相似文献   
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A pharmacological study was carried out in a group of 20 subjects composed of 13 coronary patients and 7 normal close relatives (first degree) who were considered at a high risk for coronary heart disease (CHD) because of their low levels of high density lipoprotein cholesterol (HDLch) (mean +/- SD: 34.1 +/- 5.2 mg/dl) and their high total cholesterol/HDLch (Tch/HDLch) ratio (mean +/- SD:6.7 +/- 1.1), despite their normal serum lipid values. With the purpose of normalizing these parameters they were submitted to a 4-month treatment with bezafibrate, a hypolipidemic agent which has a known effect in increasing HDLch and in decreasing the Tch/HDLch ratio. At the end of the study total serum cholesterol and triglycerides decreased significantly by 10 and 30%, respectively (p less than 0.01). HDL increased in its cholesterol content by 33% reaching a value of 45.4 +/- 9.8 mg/dl (mean +/- SD, p less than 0.01) as well as in its apolipoprotein A1 (Apo A1) content (13%, p less than 0.02). HDL2 subfraction also rose in cholesterol and in Apo A1: by 90 and 38%, respectively (p less than 0.01). HDL3 subfraction rised only its cholesterol content by 24% (p less than 0.01). Tch/HDLch ratio was significantly reduced (p less than 0.01) to a value of 4.6 +/- 0.9 (mean +/- SD). Total serum Apo B diminished by 14% (p less than 0.01). No adverse effects were observed during the follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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A randomized controlled trial of sedation in the critically ill   总被引:2,自引:0,他引:2  
A randomized controlled trial comparing: a) a combination of oral chloral hydrate and promethazine to b) a continuous intravenous midazolam infusion, for maintenance sedation in critically ill children, was carried out. The level of sedation was assessed four hourly using a specifically devized sedation scale. Forty-four children entered the study of whom two were subsequently excluded. The number of satisfactory assessments (desired and actual levels of sedation equal) was significantly greater in the chloral hydrate and promethazine group (Chi-squared P <0.01; confidence intervals of the difference 0.06 to 0.20). The number of assessments at level 5 on the sedation scale (patient restless/distressed) was significantly greater in the midazolam group (Chi-squared P <0.05). The total number of satisfactory assessments in the two groups were only 61 and 48% respectively, suggesting that sedation can be considerably improved. Chloral hydrate and promethazine are more effective than midazolam as maintenance sedation in critically ill children. It is possible to prospectively study the efficacy of sedative drugs in critically ill children.  相似文献   
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A 57-year-old woman who had been treated with an indwelling ureteral stent for over a year was admitted with massive gross hematuria caused by a fistula between the left ureter and hypogastric artery. Despite intensive radiographic evaluation, the definitive diagnosis was made only at the time of surgical exploration. Because of radiation-induced retroperitoneal fibrosis, midureteral obstruction, and prior pelvic and abdominal surgery, primary ureteral repair was not possible, and renal autotransplantation was performed. This case illustrates the need to consider the diagnosis of ureteroarterial fistula in patients with massive hematuria who have chronic indwelling stents, and the feasibility of autotransplantation when primary ureteral repair is not feasible.  相似文献   
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The objective of the study was to compare the clinical outcomes at the short-term follow-ups of two novel transobturator mid-urethral sling procedures – the transobturator tape (TOT) procedure and the tension-free vaginal tape (TVT)-obturator procedure. The study cohort consisted two groups of 40 women with urodynamically proven stress urinary incontinence (SUI). The patients in one group underwent the TOT procedure, performed according to Delorme (Prog Urol 11:1306–1313, 2001); those in the second group underwent the TVT-obturator operation, performed according to de Leval (Eur Urol 44:724–730, 2003). Intra-operative diagnostic cystoscopy was not performed with either the TVT-obturator or the TOT procedures. The average follow-up was 12 months. The two patient groups were similar in terms of demographic and therapeutic criteria, except for patient age, which was significantly younger in the TVT-obturator group. Previously reported TVT-related operative complications, such as bladder penetration, intra-operative bleeding, field infection and post-operative pelvic floor relaxation, were not observed in patients of either group. Bowel and urethral injuries were also not recorded. The therapeutic failure rates were 10% for the TOT procedure and 5% for the TVT-obturator procedure. Urinary frequency and urgency post-operatively were reported in 25% of the TOT patients and 19% of the TVT-obturator patients, pelvic or vaginal pain affected 10% of the TOT and 5% of the TVT-obturator patients, while post-operative voiding difficulty was experienced by 12.5% of the TOT and 7.5% of the TVT-obturator patients. None of the above-mentioned differences between the two patient groups were of statistical significance. The TVT-obturator and TOT procedures, both minimally invasive, novel, mid-urethral sling procedures, seem to be safe, easy-to-perform and effective in treating female SUI. The patients of both study groups suffered less intra- and post-operative surgical complications than previously been reported in connection with the TVT operation. The TVT-obturator patients had fewer therapeutic failures, less post-operative urinary frequency and urgency, less pelvic pain and less voiding difficulty. All of these findings, however, had no statistical significance; consequently, long-term comparative data collection will be required before solid conclusions can be drawn on the superiority of either of these two operative techniques.  相似文献   
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Diving medicine     
This article orients the practicing physician to the physical and physiologic basis for the more common medical problems encountered in diving, discusses the common presenting manifestations for these disorders, and provides a framework for their treatment. Medical fitness for diving is also briefly addressed.  相似文献   
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