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101.
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Objectives:   To define an exact pressure-flow correlation in the upper urinary tract using an improved measurement method, to quantitatively characterize the degree of postrenal obstruction and to find a simple way of calculating it in everyday urological practice.
Methods:   The data of 112 cases were included in the analysis. The dynamic method of a multistep, constant pressure perfusion study was used to precisely measure a wide range of pressure-flow dependences. Values of established parameters measuring the degree of obstruction were compared: the intrapelvic pressure, the ureteral opening pressure and the newly introduced 'obstruction coefficient'.
Results:   Pressure-flow relations can be best presented by a parabolic curve described by the simple formula Y = AX2 + B. Depending on the degree of obstruction, the shape of this curve can be characterized by a single number, that we defined as the 'obstruction coefficient'. Computer-based evaluation software for the easy calculation of this coefficient is presented here and freely available on demand. The Whitaker-test, the ureteral opening pressure, and the 'obstruction coefficient' showed significant correlation proving that the latter was clinically applicable in measuring the degree of obstruction.
Conclusion:   Calculation of the 'obstruction coefficient' enables us to exactly define the degree of upper urinary tract obstruction and to safely monitor for a long period conditions inhibiting ureteric passage.  相似文献   
103.
BACKGROUND: The diagnosis of analgesic nephropathy has improved significantly with modern imaging techniques. We reviewed a large portion of the Hungarian dialysis population to obtain additional insight into the problem. METHODS: Twenty-two participating dialysis units enrolled 1400 patients on renal replacement therapy between 1 January 1995 and 1 January 1998. Patients with no known aetiology (n = 284) were interviewed and studied with renal imaging. We assessed the presence of decreased renal mass combined with either bumpy contours, papillary calcification, or both. The subjects studied were interrogated extensively. RESULTS: Our survey suggested analgesic nephropathy in 47 of 1400 patients (3.3%), 3-fold higher than the EDTA database estimate for Hungary. The analgesics most commonly abused were phenacetin-containing mixtures. The driving symptoms were mainly headache and joint pain. Cardiovascular complications were more common than in the rest of the dialysis population, independent of smoking and lipid values (P<0.01). CONCLUSIONS: Phenacetin should be banned. Our study results support the need for longitudinal cohort and case-control studies in Hungary.  相似文献   
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A randomized, placebo-controlled clinical pilot study was performed in order to examine the effect of magnesium-orotate in male idiopathic infertility. Ten males were treated daily for 90 consecutive days with 3000 mg magnesium-orotate (Magnerot) tablets (Group M). As a control, ten other males were treated in the same way with placebo (Group P). Conventional microscopic sperm characteristics (sperm concentration, motility ratio, total number of motile sperm cells, normal morphology ratio), plus total and ionized magnesium levels in seminal plasma and blood serum were evaluated both prior to treatment and on day 90, at the conclusion of the study. No significant changes in sperm characteristics, blood ionized or total Mg, or ejaculate total Mg levels were detected. However, ejaculate ionized Mg levels increased in Group M from 0.18 +/- 0.05 to 0.30 +/- 0.05 (mmol/l; mean +/- SD, p < 0.05). Within the observation period of 3 months, one pregnancy occurred in the partner of a male from Group M. In conclusion, magnesium-orotate treatment at a dose of 3000 mg/day leads neither to a significant improvement of sperm variables nor does it increase the pregnancy rates of female partners of treated males as compared to those of controls. Thus, magnesium-orotate treatment was not shown to be effective therapy for idiopathic male infertility.  相似文献   
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Background  

Systematic and reliable epidemiological information at population level, preferably cross-national, is needed for an adequate planning of (end-of-life) health care policies, e.g. concerning place of death, but is currently lacking. This study illustrates opportunities and weaknesses of death certificate data to provide such information on place of death and associated factors in nine European countries (seven entire countries and five regions).  相似文献   
109.
Stenosis of the hypopharyngo-oesophageal junction can be a rare complication of laryngectomy and/or partial pharyngectomy and makes the insertion of voice prosthesis extremely difficult. This study describes the authors’ experiences gained by endoscopic balloon-catheter dilatation of hypopharyngo-oesophageal stenoses prior to implantation of voice prostheses in four cases. In two patients a single balloon-catheter dilatation resulted in wide enough pharyngo-oesophageal lumen on the long run. The average prosthesis wearing-times were 6.8 months in case 1 and 4.6 months in case 2, corresponding to the published literature data. In case 3, repeated dilatation of the pharyngo-oesophageal transition had proved to be unsuccessful despite taking every effort with the endoscopic balloon-catheter method. Having excised the stenotic segment, reconstruction with pectoralis major myocutaneous flap (PMMF) was indicated. Eighteen months later, a repeated restenosis was observed and a free jejunal flap needed to be performed as a final solution. In case 4, the insertion was carried out into a previously dilated jejunal free flap, which became gradually ischemic and stenotic since the major head-and neck procedure was carried out that resulted in prosthesis rejection after just 1 week. The authors emphasize that correct indication of pedicled and free flaps in head and neck reconstruction is a prerequisite from the aspect of prevention of pharyngo-oesophageal strictures. Endoscopic balloon-catheter dilatation is a safe and established method for dilatating hypopharyngo-oesophageal stenoses of different origin. The procedure provides maximum patient benefit with minimal trauma and morbidity; moreover, facilitates insertion of voice prostheses. However, a single balloon-catheter dilatation cannot always result in wide enough oesophageal lumen on the long run (case 3). Insertion of a voice prosthesis into a previously dilated ischemic jejunal segment is challenging and avoidable due to risks of complications.  相似文献   
110.
BACKGROUND: Depression is considered a risk factor for coronary heart disease (CHD) in initially CHD-free populations. Subclinical CHD or other somatic causes of depressive symptoms might account for the association, however. METHODS: In this case-control study, patients had had their first acute myocardial infarction (AMI). The study included 1799 cases, aged 45-70 years, and 2339, age-, gender-, and hospital-catchment-area-matched control subjects. We calculated odds ratios (OR) with 95% confidence intervals (CI) by multivariate logistic regressions to assess the AMI risk associated with a hospitalization for depression. RESULTS: Forty-seven cases and 22 control subjects had been hospitalized for depression. After adjustment for matching criteria and socioeconomic status, the OR for AMI was 2.9 (1.8-4.9) for ever hospitalized for depression. Patients hospitalized for depression before or after the median time, 15 years and 2 months, between the first hospitalization for depression and AMI, were at similar risk. Adjustment for lifestyle, lipid profile, coagulation, inflammation, prior cardiovascular events, and comorbidity only partly decreased the observed association. CONCLUSIONS: Depression was associated with increased risk for AMI. Subclinical CHD or other somatic causes are unlikely to account for our findings, which also appear not to be explained by established risk factors for AMI.  相似文献   
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