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Pathogen reduction (PR) of platelet products increases costs and available clinical studies are equivocal with respect to clinical and haemostatic effectiveness. We conducted a multicentre, open‐label, randomized, non‐inferiority trial comparing the clinical effectiveness of buffy‐coat derived leucoreduced platelet concentrates (PC) stored for up to 7 d in plasma with platelets stored in platelet additive solution III (PASIII) without and with treatment with amotosalen‐HCl/ultraviolet‐A (UVA) photochemical pathogen reduction (PR‐PASIII). Primary endpoint of the study was 1‐h corrected count increment (CCI). Secondary endpoints were 24‐h CCI, bleeding, transfusion requirement of red cells and PC, platelet transfusion interval and adverse transfusion reactions. Compared to plasma‐PC, in the intention to treat analysis of 278 evaluable patients the mean difference for the 1‐h CCI of PR‐PASIII‐PC and PASIII‐PC was −31% (P < 0·0001) and −9% (P = n.s.), respectively. Twenty‐seven patients (32%) had bleeding events in the PR‐PASIII arm, as compared to 19 (19%) in the plasma arm and 14 (15%) in the PASIII arm (P = 0·034). Despite the potential advantages of pathogen (and leucocyte) inactivation of amotosalen‐HCl/UVA‐treated platelet products, their clinical efficacy is inferior to platelets stored in plasma, warranting a critical reappraisal of employing this technique for clinical use.  相似文献   

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Unlike other types of cancer, there are several options for screening for colorectal cancer (CRC). The most extensively examined method, faecal occult blood testing (FOBT), has been shown, in three large randomized trials, to reduce mortality from CRC by up to 20% if offered biennally and possibly more if offered every year. Recently published data from the US trial suggest that CRC incidence rates are also reduced by up to 20%, but only after 18 years. In this study, the number of positive slides was associated with the positive predictive value both for CRC and adenomas larger than 1 cm, suggesting that the reduction in CRC incidence was caused by the identification and removal of large adenomas. In this respect, this study supports the concept that removing adenomas prevents CRC. More efficient methods of detecting adenomas include the use of colonoscopy or flexible sigmoidoscopy (FS). Considerable evidence exists from case-control and uncontrolled cohort studies to suggest that endoscopic screening by sigmoidoscopy reduces incidence of distal colorectal cancer. However, in the absence of evidence from a randomized trial, several countries have been reluctant to introduce endoscopic screening. Three trialsare currently in progress (in the UK, Italy and the US) to address this issue. Two of these trials are examining the hypothesis that a single FS screen at around age 55-64 might be a cost-effective and acceptable method for reducing CRC incidence rates. Recruitment and screening are now complete in both studies and the first analysis of results on incidence rates is expected in 2004. Colonoscopy screening at 10-year intervals has recently been endorsed in the US on the basis that the reductions in incidence observed with distal CRC screening can be extrapolated to the proximal colon. However, data are lacking and a pilot study for a trial of the acceptability and efficacy of colonoscopy screening is in progress in the US. It has also been suggested that FOBT testing should be used to detect proximal CRC missed by sigmoidoscopy screening, but the small amount of published data suggest that supplementing FS with FOBT offers very little advantage over FS alone. Other forms of CRC screening are under investigation and represent exciting options for the future. Extraction of DNA from stool is now feasible and a number of research groups have shown high sensitivity for CRC using a panel of DNA markers including mutations in k-ras, APC, p53 and BAT26. Data so far indicate that, with the exception of k-ras, these markers are highly specific and therefore represent a significant improvement over FOBT. Whether these tests will replace or supplement existing methods of screening has yet to be determined. It has been suggested that BAT26, which is a marker of microsatellite instability, a feature of proximal sporadic CRC, might be a useful adjunct to sigmoidoscopy screening. Others have suggested that a test for occult blood should be included with the DNA markers to further increase sensitivity. It is not yet known how sensitive these markers are for adenomas--it is only by detecting adenomas that CRC incidence rates can be reduced. A final exciting new option for screening is virtual colonoscopy (VC), which by screening out people without neoplasia allows colonoscopy to be reserved for patients requiring a therapeutic intervention. The sensitivity of VC for large adenomas and CRC appears to be high, although results vary by centre and there is a steep learning curve. Sensitivity for small adenomas is low, but perhaps it is less essential to find such lesions. Some groups have suggested that virtual colonoscopy might be a useful option for investigating patients who test positive with stool-based screening tests. Whichever CRC screening method is finally chosen (and there is no reason why several methods should not ultimately be available), high quality endoscopy resources will always be required to investigate and treat neoplastic lesions detected.  相似文献   

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Aortic valve replacement for isolated aortic regurgitation (AR) is usually not indicated unless the regurgitation is severe. However, not all patients with severe AR require aortic valve replacement. This review focuses on the causes of AR and the pathophysiology of acute versus chronic AR, and the attendant adaptive mechanisms of the left ventricle that ultimately determine their different natural histories. Aortic valve surgery must be performed in a timely manner to prevent cardiac death, ameliorate symptoms, and limit late postoperative excess mortality.  相似文献   

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The Millennium Genome Project for Hypertension was started in 2000 to identify genetic variants conferring susceptibility to hypertension, with the aim of furthering the understanding of the pathogenesis of this condition and realizing genome-based personalized medical care. Two different approaches were launched, genome-wide association analysis using single-nucleotide polymorphisms (SNPs) and microsatellite markers, and systematic candidate gene analysis, under the hypothesis that common variants have an important role in the etiology of common diseases. These multilateral approaches identified ATP2B1 as a gene responsible for hypertension in not only Japanese but also Caucasians. The high blood pressure susceptibility conferred by certain alleles of ATP2B1 has been widely replicated in various populations. Ex vivo mRNA expression analysis in umbilical artery smooth muscle cells indicated that reduced expression of this gene associated with the risk allele may be an underlying mechanism relating the ATP2B1 variant to hypertension. However, the effect size of a SNP was too small to clarify the entire picture of the genetic basis of hypertension. Further, dense genome analysis with accurate phenotype data may be required.  相似文献   

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ABSTRACT. In the Stockholm Prospective Study, 531 male and 163 female deaths had occurred during 14.5 years of observation. Deaths were divided into three categories: “ischemic”, “neoplastic” and “other” and their relations to entry characteristics were analyzed. For ischemic vascular deaths age, smoking, systolic blood pressure and triglycerides were independent risk factors for both sexes, while cholesterol and weight/height index were not. For neoplastic deaths age, smoking, systolic blood pressure and ESR were positively and cholesterol and weight/height index negatively associated. This negative association was found especially for colon carcinoma and not for, e.g., prostatic and bronchial carcinoma in men. For other deaths age, blood pressure and ESR were independent risk factors for men, and age, smoking and ESR for women.  相似文献   

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INTRODUCTION Coeliac disease (CD) is a disorder in which geneticallypredisposed individuals develop a small intestinal enteropathy on exposure to dietary gluten. The small bowel abnormalities are reversed on withdrawal of gluten from the diet. Recent popu…  相似文献   

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