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Neuropeptide Y (NPY), a potent vasoconstrictor released from the sympathetic nerves, has been suggested to counterbalance sepsis-induced vasodilation. Thus, the changes in plasma and tissue NPY concentrations in relation to hemodynamic variables and inflammatory markers in a porcine model of moderate septic shock were investigated. Susceptibility of NPY to be removed by continuous hemofiltration in two settings has been also studied. Thirty-four domestic pigs were divided into five groups: (i) control group; (ii) control group with conventional hemofiltration; (iii) septic group; (iv) septic group with conventional hemofiltration; and (v) septic group with high-volume hemofiltration. Sepsis induced by fecal peritonitis continued for 22 h. Hemofiltration was applied for the last 10 h. Hemodynamic and inflammatory parameters (heart rate, mean arterial pressure, cardiac output, systemic vascular resistance, plasma concentrations of tumor necrosis factor-α, interleukin-6, and NPY) were measured before and at 12 and 22 h of peritonitis. NPY tissue levels were determined in the left ventricle and mesenteric and coronary arteries. Sepsis induced long-lasting increases in the systemic NPY levels without affecting its tissue concentrations. Continuous hemofiltration at any dose did not reduce sepsis-induced elevations in NPY plasma concentrations, nor did it affect the peptide tissue levels. The increases in NPY systemic levels were significantly correlated with changes in the systemic vascular resistance. The results support the hypothesis of NPY implication in the regulation of the vascular resistance under septic conditions and indicate that NPY clearance rate during hemofiltration does not exceed the capacity of perivascular nerves to release it.  相似文献   
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Procoagulant factors and the risk of myocardial infarction in young women   总被引:1,自引:0,他引:1  
Abstract:  Objectives:  We investigated whether elevated levels of factor VIII, IX and XI is associated with myocardial infarction (MI) in young women. In addition, we studied ABO blood group, von Willebrand factor (VWF) and C-reactive protein (CRP). Methods and results:  We compared 200 women with MI before age 49 years with 626 controls from a population-based case–control study. Mean levels of factor VIII activity (VIII), von Willebrand factor antigen (VWF), factor IX activity (IX) were higher in patients (133, 134 and 132 IU/dL) than in controls (111, 107 and 120 IU/dL, respectively). Mean levels of factor XI (XI) were equal in patients (114 IU/dL) and controls (113 IU/dL). The odds ratio (OR) for MI for blood group non-O vs. O was 1.6 [95% confidence interval (CI) 1.1–2.3]. The OR adjusted for age, index year and area of residence for the highest quartile >150 IU/dL of factor VIII was 2.7 (95% CI 1.6–4.6), of VWF 4.7 (95% CI 2.3–9.7), of factor IX 2.6 (95% CI 1.3–5.4) and of factor XI 0.9 (95% CI 0.5–1.4), all compared with the lowest quartile <100 IU/dL. Conclusions:  Non-O blood group, high VWF, factor VIII and factor IX levels are associated with an increased risk of MI in young women, while high factor XI levels are not.  相似文献   
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The aim of our retrospective study was to analyze the clinical course and outcome of patients with immunoglobulin A (IgA) nephropathy who presented with macroscopic hematuria and acute kidney injury (AKI). During the period from 1990 to 2005, seven out of 584 adult patients with IgA nephropathy (1.2%) fulfilled the criteria for macroscopic hematuria‐induced AKI. There was an equal gender distribution among our patients, and a rather high average age at presentation (55.7 ± 10.9 years). Four patients who were oliguric upon admission to hospital needed hemodialysis treatment. The average serum creatinine at the time of kidney biopsy was 429.8 ± 377 µmol/L (median value 378). The percutaneous kidney needle biopsies showed focal proliferative crescentic glomerulonephritis of subclass III, according to the Haas scheme, associated with prominent red blood cell tubular casts and acute tubulointerstitial nephritis. Four patients with the most prominent crescents and tubulointerstitial involvement were treated with methylprednisolone. All patients, treated and untreated, recovered their kidney function (the serum creatinine at a median follow‐up of 15 months was 111.7 ± 38 µmol/L). In conclusion, AKI in IgA nephropathy accompanied by macroscopic hematuria appears to have been a reversible condition in our series of patients. Regarding pathogenesis, the kidney biopsy study points to the important role of glomerular bleeding with consequent, widespread obstructive red blood cell tubular casts accompanied by tubular injury and interstitial nephritis.  相似文献   
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The purpose of this study is to investigate whether the extraction of four premolars as a requirement of orthodontic therapy is a factor in the creation of tooth size discrepancies (TSD) (Bolton value (BV)), and to determine whether any tooth extraction combinations create more severe discrepancies comparing our result with the results from analogical studies. Hypothetical tooth extractions were performed in all cases by the following combinations: all first premolars, all second premolars, upper first and lower second premolars, and upper second and lower first premolars, estimating extraction influence on TSD frequency and size. 148 pretreatment dental casts were examined. It has been determined that in normal TBI group the smallest discrepancies were created after the second (1.087 mm) and fourth types of combinations have been chosen (1.174 mm). In a low TBI group, the smallest discrepancies occur after first (1.544 mm) and third (1.568 mm) types of removal. In high TBI group the smallest discrepancies appear after type two (3.379 mm) and type four (3.586 mm) have been chosen.  相似文献   
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