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AIM: This study evaluated regional differences in registration on the waiting list and access to liver transplantation in France. METHODS: The annual incidence of registration on the waiting list was calculated with the number of transplantation candidates registered in each region between 1996 and 1998 and was used as an indicator for access to the waiting list. The median waiting time before receiving a graft was estimated for patients registered between 1992 and 1998 by the Kaplan Meier method using transplantation as the event. This was used as an indicator for access to transplantation. Shortage of liver grafts was based on the ratio between the number of registered patients and the number of transplantations. RESULTS: The national incidence rate on the liver transplantation waiting list was 11.5 candidates per million inhabitants (pmi). There were no significant statistical differences among regions but it was high for the Rh?ne-Alpes region (18.6 pmi) and low for the French West Indies (3.6 pmi). The median waiting time before a graft is 2.2 months, and varied from 0.5 month to 3.8 months in French regions (p<0.001). Lack of a graft was strongly correlated with the median waiting time but not with the harvested liver rate. CONCLUSION: Although there is no statistical significant difference in access to the waiting list for liver transplantations, access to grafts differs among the regions in France.  相似文献   
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BACKGROUND: Cancer-related cachexia is caused by a diverse combination of accelerated protein breakdown and slowed protein synthesis. The hypothesis proposed in this study is that supplementation of specific nutrients known to positively support protein synthesis and reduce protein breakdown will reverse the cachexia process in advanced cancer patients. METHODS: Patients with solid tumors who had demonstrated a weight loss of at least 5% were considered for the study. Patients were randomly assigned in a double-blind fashion to either an isonitrogenous control mixture of nonessential amino acids or an experimental treatment containing beta-hydroxy-beta-methylbutyrate (3 g/d), L-arginine (14 g/d), and L-glutamine (14 g/d [HMB/Arg/Gln]). The primary outcomes measured were the change in body mass and fat-free mass (FFM), which were assessed at 0, 4, 8, 12, 16, 20, and 24 weeks. RESULTS: Thirty-two patients (14 control, 18 HMB/Arg/Gln) were evaluated at the 4-week visit. The patients supplemented with HMB/Arg/Gln gained 0.95 +/- 0.66 kg of body mass in 4 weeks, whereas control subjects lost 0.26 +/- 0.78 kg during the same time period. This gain was the result of a significant increase in FFM in the HMB/Arg/Gln-supplemented group (1.12 +/- 0.68 kg), whereas the subjects supplemented with the control lost 1.34 +/- 0.78 kg of FFM (P = 0.02). The response to 24-weeks of supplementation was evaluated by an intent-to-treat statistical analysis. The effect of HMB/Arg/Gln on FFM increase was maintained over the 24 weeks (1.60 +/- 0.98 kg; quadratic contrast over time, P <0.05). There was no negative effect of treatment on the incidence of adverse effects or quality of life measures. CONCLUSIONS: The mixture of HMB/Arg/Gln was effective in increasing FFM of advanced (stage IV) cancer. The exact reasons for this improvement will require further investigation, but could be attributed to the observed effects of HMB on slowing rates of protein breakdown, with improvements in protein synthesis observed with arginine and glutamine.  相似文献   
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Doppler and direct measurements of right ventricle to right atrial pressure drop were made during cardiac catheterisation on 28 occasions in 26 infants with congenital heart disease. Age was 10 days to 12 months (median 4.5 months), and weight was 3.1 to 9.0 kg (median 4.7 kg). We measured peak velocity of tricuspid regurgitation by continuous wave Doppler, and the pressure drop was calculated using the modified Bernoulli equation (delta p = 4v2). There was a high correlation (r = 0.95) between direct and Doppler measurements. Doppler values tended to underestimate the right ventricle to right atrial pressure drop, but this was not of clinical significance (mean 2 mm Hg). The 95% confidence interval for the Doppler velocity was -0.41 to +0.26 m/sec, and was consistent across the range of pressures studied. Variability between observers was tested, by two observers performing sequential paired examinations on 16 newborn babies with tricuspid regurgitation. The coefficient of repeatability was 6.3 mm Hg (95% confidence interval 4.7 to 9.5 mm Hg) or 0.26 m/sec (0.18 to 0.50 m/sec). This method of right ventricular pressure estimation, validated previously only in older children and adults, is a reproducible and accurate technique in infants with tricuspid regurgitation.  相似文献   
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PURPOSE: Overactive bladder (OAB) is a syndrome consisting of urinary urgency with or without urge incontinence, usually with increased urinary frequency and nocturia. In response to current limitations in OAB clinical research a new patient reported measure of urgency severity associated with OAB has been developed, namely the Indevus Urgency Severity Scale (IUSS). We report the measurement properties of the IUSS. MATERIALS AND METHODS: Validation study data were collected alongside a phase III clinical trial of 20 mg trospium chloride twice daily vs placebo in patients with OAB associated with urge incontinence. We evaluated IUSS item variability, known group, content, criterion and construct validity, test-retest reliability, responsiveness and respondent burden. RESULTS: A total of 658 patients were evaluated at baseline and 579 were reevaluated at week 12. IUSS demonstrated good item variability. Greater urgency severity was associated with increased symptom bother and worse health related quality of life, as measured by the OAB QOL questionnaire. IUSS had a significant positive association with essential clinical and quality of life outcomes, demonstrating content validity. IUSS was highly responsive to a decrease in the average number of patient toilet voids per 24 hours to 7 or fewer toilet voids and average urge incontinence episodes per 24 hours to zero. It discriminated between patients who had above and below the median number of toilet voids and urge incontinence episodes per 24 hours. IUSS also had good test-retest reliability and content validity, and it created minimal respondent burden. CONCLUSIONS: IUSS is a validated patient reported measure of urgency severity for collecting event specific information in the context of a clinical trial.  相似文献   
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The costal and crural parts of the diaphragm differ in their embryological development and physiological function. It is not known if this is reflected in differences in their motor cortical representation. We compared the response of the costal and crural diaphragms using varying intensities of transcranial magnetic stimulation of the motor cortex at rest and during submaximal and maximal inspiratory efforts. The costal and crural motor evoked potential recruitment curves during submaximal inspiratory efforts were similar. The response to stimulation before, during and at 10 and 30 min after 44 consecutive maximal inspiratory efforts was also the same. Using paired stimulations to investigate intra-cortical facilitatory and inhibitory circuits we found no difference between the costal and crural response with varying interstimulus intervals, or when conditioning and test stimulus intensity were varied. We conclude that supraspinal control of the costal and crural diaphragm is identical during inspiratory tasks.  相似文献   
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