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71.
72.
Simon Bradette MD FRCPC Mathieu Béland MD FRCPC Catherine Lalonde MD FRCPC 《Journal of cardiac surgery》2020,35(10):2808-2810
Hemorrhagic extension along the pulmonary arteries should be recognized as a complication of Stanford type A aortic dissection. Radiologists and other physicians with an interest in cardiothoracic imaging should be aware of this rare but life-threatening pathology. The anatomical concept of the pathology is outlined in this text, through high-quality electrocardiogram-gated computerized tomography images. 相似文献
73.
Andre C. Felicio MD PhD Katherine Dinelle MSc Pankaj A. Agarwal MD DNB DM Jessamyn McKenzie LPN Nicole Heffernan RN Jeremy D. Road MD Silke Appel‐Cresswell MD Zbigniew K. Wszolek MD Matthew J. Farrer PhD Michael Schulzer MD PhD Vesna Sossi PhD A. Jon Stoessl CM MD FRCPC 《Movement disorders》2014,29(9):1197-1201
74.
Yun-Bi Ni MMSC Julia Y. S. Tsang PhD Siu Ki Chan FHKCPath Gary M. Tse FRCPC 《Annals of surgical oncology》2014,21(9):2928-2933
Background
Histologic grade, TNM stage, and Nottingham Prognostic Index are traditional prognostic tools for breast cancer. “IHC-molecular” classification of breast cancer can also identify patients at different recurrence risks and provides insight into cancer therapy. However, cancers in each group are heterogeneous. A model based on the comprehensive analysis of morphologic features and molecular subtype was constructed to predict recurrence and refine these traditional prognostic tools.Methods
Morphologic features including histologic grade, fibrotic focus, extensive intraductal component, lymphocytic infiltrate, lymphovascular invasion, tumor necrosis, tumor margin and TNM stage, and molecular subtypes approximated by immunohistochemistry were analyzed in 633 patients with invasive breast carcinoma (excluding those with HER2 targeted therapy). Significant independent predictors for recurrence included: high histologic grade (p = 0.004), presence of lymphovascular invasion (p = 0.004), fibrotic focus (p = 0.020), mild lymphocytic infiltrate (p = 0.013), high TNM stage (p < 0.001), and HER2-overexpressing (p = 0.004) and basal-like (p < 0.001) molecular subtypes. A morphologic-molecular recurrence predictive model based on these features was useful in recurrence prediction, independent of treatment modalities, and was able to refine the traditional prognostic tools of histologic grade, TNM stage, and Nottingham prognostic index, particularly for intermediate-risk groups, and to refine the luminal group molecular subtypes. Such findings were reproducible with a validation cohort.Conclusion
TNM stage, histologic grade, lymphovascular invasion, fibrotic focus, mild lymphocytic infiltrate, HER2-overexpressing and basal-like molecular subtypes were important independent recurrence risk factors for breast cancer. This morphologic-molecular model was robust in recurrence prediction and refined recurrence risk stratified by the traditional prognostic parameters, independent of treatment modalities. 相似文献75.
Dr. L. S. Valberg FRCPC P. R. Flanagan PhD C. N. Ghent FRCPC M. J. Chamberlain FRCPC 《Digestive diseases and sciences》1985,30(4):329-333
To determine if malabsorption of zinc contributes to the zinc deficiency found in cirrhosis, the absorption of an oral dose of ZnCl2, labeled with65Zn and a nonabsorbed marker51CrCl3, was determined from the ratio of these isotopes in a stool specimen. Average65Zn absorption in 25 alcoholic cirrhotics, 37±17% (sd), was low compared to 55±16% in 31 healthy volunteer controls (P<0.01). In contrast, mean65Zn absorption, 47±11%, in 11 nonalcoholic cirrhotics was not significantly different from the average result in healthy controls. Low65Zn absorption was accompanied by low leukocyte zinc in a subgroup of alcoholic cirrhotics with ascites and/or ascites and encephalopathy, but not in the subgroup in which these clinical features were absent. Thus, low zinc absorption contributes to zinc deficiency in decompensated alcoholic cirrhosis. The failure to find similar abnormalities in nonalcoholic cirrhosis suggests that the long-standing consumption of alcoholic beverages contributes to the malabsorption of zinc.Supported by a grant from the Medical Research Council. 相似文献
76.
77.
The management of ventricular tachyarrhythmias has changed significantly over the past several decades. The advent of readily available implantable cardioverter defibrillators (ICDs) has had the greatest effect, with important mortality effects in patients with ventricular tachycardia and structural heart disease. ICDs have been shown to reduce sudden death in patients with ischemic and nonischemic cardiomyopathies; evidence of adverse consequences of ICD shocks, however, is mounting. In addition to the negative effects on patient-reported quality of life, anxiety, and depression, frequent ventricular arrhythmias and ICD shocks have also been associated with increased mortality. It is therefore important to identify and implement effective ventricular tachycardia-suppressive strategies. Antiarrhythmic drugs represent one such method, but are challenged by unfavourable side effect profiles and proarrhythmic risk. Catheter ablation of ventricular tachycardia is now a well-accepted intervention, which has been demonstrated to reduce recurrent arrhythmias. Questions persist regarding the optimal role for ablation compared with drug therapy. 相似文献
78.
Transplant candidates might manifest circulating antibodies against human leukocyte antigens and nonhuman leukocyte antigens, a condition termed allosensitization. The presence of these antibodies decreases a given candidate's possible donor pool, thereby prolonging the time to transplantation. They are also associated with poorer posttransplant outcomes including increased morbidity and mortality. With the increasing use of ventricular assist devices as a bridge to transplantation, the prevalence of allosensitized transplant candidates has increased. This has implications for transplant programs in terms of donor-recipient matching and managing transplant-related complications, which are more common in this high risk cohort. Controversy exists as to the best approach in managing sensitized patients, before and after transplantation. Transplant centres have used various strategies to reduce antibody loads with mixed results being reported; moreover, it remains unclear as to whether attempts at desensitization translate into better posttransplant outcomes. As an alternative management approach, some centres participate in large organ sharing strategies and allocate organs based on the probability of finding a successful donor-recipient match. In this article, the immunological basis of allosensitization, its causes, implications, and therapeutic strategies to manage sensitized patients are reviewed. The literature in relation to desensitization therapies in heart transplant candidates is also reviewed. 相似文献
79.
80.
Maggie Tillquist MD Demetrios J. Kutsogiannis MD MHS FRCPC Paul E. Wischmeyer MD Christine Kummerlen MD Roger Leung BSc Daniel Stollery MD FCCP FRCPC Constantine J. Karvellas MD FRCPC Jean‐Charles Preiser MD PhD Nora Bird VMD BS RDMS Rosemary Kozar MD PhD Daren K. Heyland MD FRCPC MSc 《JPEN. Journal of parenteral and enteral nutrition》2014,38(7):886-890
Background: Critically ill patients commonly experience skeletal muscle wasting that may predict clinical outcome. Ultrasound is a noninvasive method that can measure muscle quadriceps muscle layer thickness (QMLT) and subsequently lean body mass (LBM) at the bedside. However, currently the reliability of these measurements are unknown. The objectives of this study were to evaluate the intra‐ and interreliability of measuring QMLT using bedside ultrasound. Methods: Ultrasound measurements of QMLT were conducted at 7 centers on healthy volunteers. Trainers were instructed to perform measurements twice on each patient, and then a second trainee repeated the measurement. Intrarater reliability measured how consistently the same person measured the subject according to intraclass correlation (ICC). Interrater reliability measured how consistently trainer and trainee agreed when measuring the same subject according to the ICC. Results: We collected 42 pairs of within operator measurements with an ICC of .98 and 78 pairs of trainer‐to‐trainee measurements with an ICC of .95. There were no statistically significant differences between the trainer and trainee results (trainer and trainee mean = ?0.028 cm, 95% CI = ?0.067 to ?0.011, P = .1607). Conclusions: Excellent intra‐ and interrater reliability for ultrasound measurements of QMLT in healthy volunteers was observed when performed by a range of providers with no prior ultrasound experience, including dietitians, nurses, physicians, and research assistants. This technique shows promise as a method to evaluate LBM status in ICU or hospital settings and as a method to assess the effects of nutrition and exercise‐based interventions on muscle wasting. 相似文献