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21.
  • Transcatheter electrosurgery has emerging value in a range of other new procedures that require traversing tissue (transcaval access, transcatheter Glenn Shunt) or slicing tissue (LAMPOON slicing of the mitral valve and BASILICA slicing of the aortic valve).
  • This is the first report of bipolar radiofrequency wires used to cross lesions in humans, reported here in seven re‐entry CTO cases.
  • The bipolar configuration may provide directionality to charge without need for wire alignment and advancement, but is theoretically disadvantageous for tissue “cutting” because of problems with charge concentration.
  相似文献   
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BACKGROUND: The clinical significance of colorectal wall thickening (CRWT) in patients undergoing abdominal computed tomography (CT) has not yet been definitively established. OBJECTIVES: To compare alleged findings on abdominal CT with those of a follow-up colonoscopy. METHODS: Ninety-four consecutive patients found to have large-bowel abnormalities on abdominal CT were referred for colonoscopy. Of these patients, 48 were referred for a suspected colorectal tumour and 46 for CRWT. Colonoscopy was performed and findings were compared. RESULTS: Of the 48 suspected colorectal tumours, 34 were determined to be neoplastic lesions on colonoscopy. Of these, 26 were malignant and eight were benign. Colonoscopy revealed no abnormality in 30 of 46 patients with CRWT as a solitary finding, and revealed some abnormality in 16 patients (12 had diverticular disease, four had benign neoplastic lesions). CONCLUSIONS: CRWT as an incidental and solitary finding on CT should not be regarded as a pathology prompting a colonoscopy. Approximately two-thirds of the patients had a normal colonoscopy and the remaining patients had benign lesions (12 had diverticular disease and four had benign neoplastic lesions). However, many of these patients seem to warrant colonoscopy regardless of CT findings, particularly patients who have a family history of colorectal cancer, have positive fecal occult blood test results or who are older than 50 years of age.  相似文献   
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Background

The 2013 ACC/AHA Report on the Assessment of Cardiovascular (CVD) Risk redefined “intermediate risk”. We sought to critically compare the intermediate risk groups identified by prior guidelines and the new ACC/AHA guidelines.

Methods

We analyzed data from 30,005 adult men free of known CVD from a large, multi-ethnic study of middle-aged adults. The Framingham Risk Score was calculated using published equations, and CVD risk was calculated using the new ACC/AHA Pooled Cohort Equations Risk Estimator. We first compared the size and characteristics of the intermediate risk group identified by the old (ATP III, 10–20% 10-year CHD risk) and new guidelines (5–7.4% 10-year CVD risk). We then defined time-to-high-risk as the length of time an individual patient resides in the intermediate risk group before progressing to high risk status based on advancing age alone.

Results

The mean age of the study population was 53 ± 13 years, and 24% were African-American. Patients identified as intermediate risk by the new ACC/AHA Guidelines were younger and more likely to be African-American and have lower risk factor burden (all p < 0.05). The new intermediate risk group was just 37% the size of the traditional ATP III intermediate risk group, while the new high risk group was 103% larger. Under the new guidelines, men remain intermediate risk for an average of just 3 years, compared to 8 years under the prior guidelines (63% shorter time-to-high-risk, p < 0.05), before progressing to high risk based on advancing age alone.

Conclusion

The new 2013 ACC/AHA risk assessment guidelines produce a markedly smaller, lower absolute risk, and more temporary “intermediate risk” group. These findings reshape the modern understanding of “intermediate risk”, and have distinct implications for risk assessment, clinical decision making, and pharmacotherapy in primary prevention.  相似文献   
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Mononuclear cells, isolated from the blood of hyperlipidaemic patients, are hyper-reactive and possess an increased propensity to adhere to vascular endothelial cells. Hyperlipidaemia is also associated with a dysfunctional endothelium, to which mononuclear cells stick with greater avidity. In order to assess the importance of lipid peroxidation and free- adical generation in these processes, we have investigated the effects of probucol on mononuclear cell adhesion to vascular endothelial cells in vivo and in vitro in the cholesterol-fed rabbit. New Zealand White rabbits were fed either: (i) control chow (n = 15), (ii) 2% cholesterol (n = 11), or (iii) 2% choles erol with 1% probucol (n = 11). Mononuclear cell adherence to endothelium in the common carotid artery was assessed 5 weeks after the start of the experimental diet using the Hoechst 33342 staining technique. The 2% cholesterol diet caused a more than 6-fold increase in mean mononuclear cell adherence (P < 0.001). Concurrent probucol therapy abrogated the effects of cholesterol feeding, and in animals in this group, in vivo mononuclear cell adherence did not differ significantly from control animals. In vivo mononuclear cell adherence was directly related to serum cholesterol levels (r = 0.68, P < 0.0001) and inversely related to serum probucol concentrations (r = −0.63, P < 0.002). Concurrent probucol therapy also reduced the in vitro binding of mononuclear cells, isolated from hypercholesterolaemic animals, to endothelial cell monolayers (P < 0.01). These data suggest that the increased binding of mononuclear cells to vascular endothelium of cholesterol-fed rabbits may be a free radical mediated process that is inhibited by antioxidants.  相似文献   
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In September 2012, a novel coronavirus was isolated from a patient who died in Saudi Arabia after presenting with acute respiratory distress and acute kidney injury. Analysis revealed the disease to be due to a novel virus which was named Middle East Respiratory Coronavirus (MERS-CoV). There have been several MERS-CoV hospital outbreaks in KSA, continuing to the present day, and the disease has a mortality rate in excess of 35%. Since 2012, the World Health Organization has been informed of 2220 laboratory-confirmed cases resulting in at least 790 deaths. Cases have since arisen in 27 countries, including an outbreak in the Republic of Korea in 2015 in which 36 people died, but more than 80% of cases have occurred in Saudi Arabia.. Human-to-human transmission of MERS-CoV, particularly in healthcare settings, initially caused a ‘media panic’, however human-to-human transmission appears to require close contact and thus far the virus has not achieved epidemic potential. Zoonotic transmission is of significant importance and evidence is growing implicating the dromedary camel as the major animal host in spread of disease to humans. MERS-CoV is now included on the WHO list of priority blueprint diseases for which there which is an urgent need for accelerated research and development as they have the potential to cause a public health emergency while there is an absence of efficacious drugs and/or vaccines. In this review we highlight epidemiological, clinical, and infection control aspects of MERS-CoV as informed by the Saudi experience. Attention is given to recommended treatments and progress towards vaccine development.  相似文献   
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