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When a cost-effectiveness analysis is implemented, the health-care system is usually assumed to adjust smoothly to the proposed new strategy. However, technological innovations in health care may often induce friction in the organization of care supply, implying the congestion of services and subsequent waiting times. Our objective here is to measure how these short run rigidities can challenge cost-effectiveness recommendations favorable to an innovative mass screening test for colorectal cancer. Using Markov modeling, we compare the standard Guaiac fecal occult blood test (gFOBT) with an innovative screening test for colorectal cancer, namely the immunological fecal occult blood test (iFOBT). Waiting time can occur between a positive screening test and the subsequent confirmation colonoscopy. Five scenarios are considered for iFOBT: no further waiting time compared with gFOBT, twice as much waiting time for a period of 5 or 10 years, and twice as much waiting time for a period of 5 or 10 years combined with a 25 % decrease in participation to confirmation colonoscopies. According to our modeling, compared with gFOBT, iFOBT would approximately double colonoscopy demand. Probabilistic sensitivity analysis enables concluding that the waiting time significantly increases the uncertainty surrounding recommendations favorable to iFOBT if it induces a decrease in the adherence rate for confirmation colonoscopy.  相似文献   
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Introduction  

Obstructive sleep apnea (OSA) affects up to 30% of the adult population and is a risk factor for coronary artery disease (CAD). The diagnostic process, involving polysomnography, may be complex. Berlin questionnaire (BQ) is a validated and economical screening tool.  相似文献   
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Epidemiology suggests that processed meat is associated with colorectal cancer risk, but few experimental studies support this association. We have shown that a model of cured meat made in a pilot workshop promotes preneoplastic lesions, mucin‐depleted foci (MDF) in the colon of rats. This study had two aims: to check if real store‐bought processed meats also promote MDF, and to test if calcium carbonate, which suppresses heme‐induced promotion, can suppress promotion by processed meat. A 14‐day study was done to test the effect of nine purchased cured meats on fecal and urinary biomarkers associated with heme‐induced carcinogenesis promotion. Fecal water from rats given hot dog or fermented raw dry sausage was particularly cytotoxic. These two cured meats were thus given to rats pretreated with 1,2‐dimethylhydrazine, to evaluate their effect on colorectal carcinogenesis. After a 100‐days feeding period, fecal apparent total N‐nitroso compounds (ATNC) were assayed and colons were scored for MDF. Hot dog diet increased fecal ATNC and the number of MDF per colon compared with the no‐meat control diet (3.0 ± 1.7 vs. 1.2 ± 1.4, p < 0.05). In a third study, addition of calcium carbonate (150 µmol/g) to the hot dog diet decreased the number of MDF/colon and fecal ATNC compared with the hot dog diet without calcium carbonate (1.2 ± 1.1 vs. 2.3 ± 1.4, respectively, p < 0.05). This is the first experimental evidence that a widely consumed processed meat promotes colon carcinogenesis in rats. It also shows that dietary prevention of this detrimental effect is possible.  相似文献   
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Patterning of the vertebrate skeleton requires the coordinated activity of Hox genes. In particular, Hox10 proteins are essential to set the transition from thoracic to lumbar vertebrae because of their rib-repressing activity. In snakes, however, the thoracic region extends well into Hox10-expressing areas of the embryo, suggesting that these proteins are unable to block rib formation. Here, we show that this is not a result of the loss of rib-repressing properties by the snake proteins, but rather to a single base pair change in a Hox/Paired box (Pax)-responsive enhancer, which prevents the binding of Hox proteins. This polymorphism is also found in Paenungulata, such as elephants and manatees, which have extended rib cages. In vivo, this modified enhancer failed to respond to Hox10 activity, supporting its role in the extension of rib cages. In contrast, the enhancer could still interact with Hoxb6 and Pax3 to promote rib formation. These results suggest that a polymorphism in the Hox/Pax-responsive enhancer may have played a role in the evolution of the vertebrate spine by differently modulating its response to rib-suppressing and rib-promoting Hox proteins.  相似文献   
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International Urology and Nephrology - The optimal vitamin D3 therapy for the treatment of secondary hyperparathyroidism (SHPT) in chronic hemodialysis patients is still controversial. Recent...  相似文献   
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