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991.
Review of the most significant surveys (data base: Pub Med on September 2003) of elective open surgery for Juxtarenal aneurysms and personal results of 106 cases (9.3% of AAA consecutively operated in the last 11 yrs.) are reported. Mortality and morbidity are discussed related to: technique of aortic cross-clamping; protective measures on splanchnic and renal perfusion; risks from previous CAD and chronic renal failure. Over all, the main predictive factor is the accuracy of the selected technique, without any difference among different approaches, and the same results of infrarenal aneurysms can be obtained.  相似文献   
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Background: Hereditary haemochromatosis, a disease that affects iron metabolism, progresses with a greater or lesser tendency to induce iron overload, possibly leading to severe organ dysfunction. Most elite endurance athletes take iron supplements during their active sporting life, which could aggravate this condition.

Objective: To determine the prevalence and discuss potential clinical implications of mutations of HFE (the gene responsible for hereditary haemochromatosis) in endurance athletes.

Methods: Basal concentrations of iron, ferritin, and transferrin and transferrin saturation were determined in the period before competition in 65 highly trained athletes. Possible mutations in the HFE gene were evaluated in each subject by extracting genomic DNA from peripheral blood. The restriction enzymes SnaBI and BclI were used to detect the mutations 845G→A (C282Y) and 187C→G (H63D).

Results: Our findings indicate a high prevalence of HFE gene mutations in this population (49.2%) compared with sedentary controls (33.5%). No association was detected in the athletes between mutations and blood iron markers.

Conclusions: The findings support the need to assess regularly iron stores in elite endurance athletes.

  相似文献   
996.
Background: Continued exposure to prolonged periods of intense exercise may unfavourably alter neuroendocrine, neuromuscular, and cardiovascular function.

Objective: To examine the relation between quantifiable levels of exertion (TRIMPS) and resting heart rate (HR) and resting supine heart rate variability (HRV) in professional cyclists during a three week stage race.

Method: Eight professional male cyclists (mean (SEM) age 27 (1) years, body mass 65.5 (2.3) kg, and maximum rate of oxygen consumption (V·O2MAX) 75.6 (2.2) ml/kg/min) riding in the 2001 Vuelta a España were examined for resting HR and HRV on the mornings of day 0 (baseline), day 10 (first rest day), and day 17 (second rest day). The rest days followed stages 1–9 and 10–15 respectively. HR was recorded during each race stage, and total HR time was categorised into a modified, three phase TRIMPS schema. These phases were based on standardised physiological laboratory values obtained during previous V·O2MAX testing, where HR time in each phase (phase I = light intensity and less than ventilatory threshold (VT; ~70% V·O2MAX); phase II = moderate intensity between VT and respiratory compensation point (RCP; ~90% V·O2MAX); phase III = high intensity (>RCP)) was multiplied by exertional factors of 1, 2, and 3 respectively.

Results: Multivariate analysis of variance showed that total TRIMPS for race stages 1–9 (2466 (90)) were greater than for stages 10–15 (2055 (65)) (p<0.0002). However, TRIMPS/day were less for stages 1–9 (274 (10)) than for stages 10–15 (343 (11)) (p<0.01). Despite a trend to decline, no difference in supine resting HR was found between day 0 (53.2 (1.8) beats/min), day 10 (49.0 (2.8) beats/min), and day 17 (48.0 (2.6) beats/min) (p = 0.21). Whereas no significant group mean changes in HR or HRV indices were noted during the course of the race, significant inverse Pearson product-moment correlations were observed between all HRV indices relative to total TRIMPS and TRIMPS/day accumulated in race stages 10–15. Total TRIMPS correlated with square root of mean squared differences of successive RR intervals (r = –0.93; p<0.001), standard deviation of the RR intervals (r = –0.94; p<0.001), log normalised total power (r = –0.97; p<0.001), log normalised low frequency power (r = –0.79; p<0.02), and log normalised high frequency power (r = –0.94; p<0.001).

Conclusion: HRV may be strongly affected by chronic exposure to heavy exertion. Training volume and intensity are necessary to delineate the degree of these alterations.

  相似文献   
997.
BACKGROUND: Calcineurin-inhibitor (CNI)-related renal failure is a common problem after cardiac transplantation (HTx). The aim of this study was to introduce a CNI-free immunosuppressive regimen to HTx recipients with late posttransplant renal impairment and to evaluate the impact of conversion to this new immunosuppression (mycophenolate mofetil [MMF] and sirolimus [Sir]) treatment on renal function. METHODS AND RESULTS: Thirty-one HTx patients (25 men, 6 women; 0.2-14.2 years after transplantation) with CNI-based immunosuppression and a serum creatinine greater than 1.9 mg/dL were included in the study. Creatinine and cystatin levels were monitored to detect renal function. Mean patient age was 50+/-14 (range 19-74) years. Conversion was started with 6 mg Sir, continued with 2 mg, and the dose was adjusted to achieve target trough levels between 8 and 14 ng/mL. MMF was continued with trough level adjusted (1.5-4 microg/mL). Subsequently, the CNIs were tapered down and stopped. Clinical follow-up (first and every 3 months after conversion) included endomyocardial biopsies, echocardiography, and laboratory studies. Survival was 90% after a mean follow-up of 13+/-95 months. No acute rejection episode was detected during the study period. Renal function improved significantly after conversion: creatinine preconversion vs. postconversion: 3.14+/-0.76 mg/dL vs. 2.14+/-0.83 mg/dL, P =0.001. Cystatin preconversion vs. postconversion: 2.95+/-1.06 mg/L vs. 2.02+/-1.1 mg/L, P =0.01. In three patients, hemodialysis therapy was stopped completely after conversion. Graft function remained stable. Fractional shortening preconversion vs. postconversion: 36.9+/-6% vs. 36.4+/-6%. There were no serious adverse events. One patient had to be excluded because of noncompliance. CONCLUSIONS: Conversion from CNI-based immunosuppression to MMF and Sir in HTx patients with chronic renal failure was safe, preserved graft function, and improved renal function.  相似文献   
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Purpose

The aim of this study was to assess parent’s emotional and cognitive reactions to the prenatal diagnosis of diaphragmatic hernia in their prospective children.

Methods

A survey was conducted by means of a questionnaire. In the period ranging from 1997 to 2002, 40 couples in whom an established diagnosis of diaphragmatic hernia was made in their fetus were seen for prenatal consultation at a tertiary referral center.

Results

Overall response rate was 93% (37 couples). Mean period since diagnosis for compilation of the questionnaire was 2 weeks. Mean gestational age at diagnosis was 25 weeks (range, 16 to 35 weeks). All parents lacked prediagnostic knowledge of diaphragmatic hernia and consider a single consultation with the paediatric surgeon inadequate to have a clear understanding of the anomaly. Only 1 mother and 1 father reported they understood all the information given by the surgeon. The most frequent (75%) feeling during and after the consultation was fear. Most parents (70%) referred to the intense emotions as the factor that made it difficult to follow the surgeon’s explanations as well as to ask questions.

Conclusions

Because of the incompatibility of emotional distress and optimum learning, impairment of early comprehension of information about diaphragmatic hernia is unavoidable. Therefore, we believe that follow-up antenatal consultations and provision of written and visual illustration are extremely important to facilitate informed choices.  相似文献   
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