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Mak  Lung-Yi  Huang  Qi  Wong  Danny Ka-Ho  Stamm  Luisa  Cheung  Ka-Shing  Ko  Kwan-Lung  Yan  Ran  Ouyang  Lea  Fung  James  Seto  Wai-Kay  Yuen  Man-Fung 《Journal of gastroenterology》2021,56(5):479-488
Journal of Gastroenterology - We aimed to assess whether residual hepatitis B virus (HBV) viraemia is associated with HCC development. This is a case–control study of 104 patients [52 HCC and...  相似文献   
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BACKGROUND: Increased pulmonary capillary pressure (PAWP) and decreased serum colloid osmotic pressure (COP) are important factors in pulmonary edema (PE) formation. The aim of this study was to evaluate the clinical usefulness of noninvasive determination of COP, PAWP and COP-PAWP gradient in patients with acute dyspnea. METHODS: Thirty four patients presenting with PE, 19 with preserved left ventricular systolic function (Ia) and 15 with depressed systolic function (Ib), and 26 patients presenting with acute pulmonary diseases (II) were enrolled. COP was estimated using Landis and Pappenheimer formula (COP = 2.1 x P + 0.16 x P2 + 0.009 x P3, P: serum total protein concentration). PAWP was measured by transthoracic Doppler echocardiography using E/Vp and 1000/(2 x IPT + Vp) Doppler indexes. RESULTS: The mean value of the gradient was 0.5 +/- 5, 1.7 +/- 3.4 and 10.4 +/- 4.7 mmHg in Ia, Ib and II respectively (P < 0.001 Ia and Ib vs II). PAWP was higher in Ia and Ib than in II (P < 0.001). However, hypoalbuminemia with COP < or = 18 mmHg was observed in 63% of patients in Ia as compared to those in Ib (7%) and II (8%). CONCLUSIONS: Severe hypoalbuminemia frequently contributes to PE formation in the presence of normal left ventricular systolic function. A COP-PAWP gradient value lower than 6 mmHg is highly predictive of the diagnosis of acute heart failure in these patients presenting with acute dyspnea.  相似文献   
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Successful transformation and subsequent genetic manipulation of Mycobacterium avium requires suitable vectors, efficient transformation systems, and reliable selectable markers. A systematic analysis of the parameters involved in the transformation of M. avium was performed to optimize DNA transfer. Factors examined included the composition of the growth medium, growth medium additives, variations in washing of the bacteria prior to electroporation, and conditions of electroporation. Of the parameters assayed, the frequency of transformation (defined as the number of transformants per 10(6) transformed bacteria) showed the greatest increase with the addition of 1.5% glycine to the M. avium culture medium and the use of higher concentrations of plasmid DNA. The addition of 0.5 M sucrose to the growth medium and wash solution yielded a modest increase in transformation frequency, but more importantly afforded greater consistency of results between different batches of cells with no decrease in transformation yields following freezing and thawing. We also confirmed that gfp could be used as a selective marker for M. avium, even as a single copy integrant, and allowed for rapid discrimination between false and true transformants. Using this protocol, we were able to transform nine of 11 clinical strains of M. avium.  相似文献   
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Ventricular fibrillation and subsequent death frequently occur so soon after coronary artery occlusion that infarct size cannot be determined; thus the systematic study of their relationship is impossible. Recently, however, a technique has been developed that permits the assessment, in vivo, of the extent of the myocardial hypoperfused zone (HZ). Accordingly, in 55 open-chest dogs, 99mTc-labeled (8 mCi) albumin microspheres (15 microns in diameter) were injected into the left atrium 1 minute after coronary artery occlusion. The zone of hypoperfusion was analyzed in 28 dogs that had ventricular fibrillation (group A) and 27 dogs that had no ventricular fibrillation (group B). In group B, the HZ was 26.3 +/- 1.7% of the left ventricle vs 31.6 +/- 1.3% of the left ventricle in group A (p less than 0.05), showing that ventricular fibrillation occurred in dogs with larger zones of hypoperfusion.  相似文献   
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We report a patient born with a Holmes heart who was later diagnosed with pheochromocytoma in her teenage years. A review of the literature showed only two such cases reported. The findings of these two rare conditions simultaneously in several individuals is suggestive of an association.  相似文献   
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