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Karan Singh Arora Nuzhath Khan Hamid Abboudi Mohammed S. Khan Prokar Dasgupta Kamran Ahmed 《Postgraduate medicine》2015,127(2):202-214
Objectives. The aim of this systematic review is to evaluate the learning curve (LC) literature and identify the LC of cardiothoracic and vascular surgical procedures. Summary and background. The LC describes an observation that a learner’s performance improves over time during acquisition of new motor skills. Measuring the LC of surgical procedures has important implications for surgical innovation, education, and patient safety. Numerous studies have investigated LCs of isolated operations in cardiothoracic and vascular surgeries, but a lack of uniformity in the methods and variables used to measure LCs has led to a lack of systematic reviews. Methods. The MEDLINE®, EMBASE?, and PsycINFO® databases were systematically searched until July 2013. Articles describing LCs for cardiothoracic and vascular procedures were included. The type of procedure, statistical analysis, number of participants, procedure setting, level of participants, outcomes, and LCs were reviewed. Results. A total of 48 studies investigated LCs in cardiothoracic and vascular surgeries. Based on operating time, the LC for coronary artery bypass surgery ranged between 15 and 100 cases; for endoscopic vessel harvesting and other cardiac vessel surgery between 7 and 35 cases; for valvular surgery, which included repair and replacement, between 20 and 135 cases; for video-assisted thoracoscopic surgery, between 15 and 35 cases; for vascular neurosurgical procedures between 100 and 500 cases, based on complications; for endovascular vessel repairs between 5 and 40 cases; and for ablation procedures between 25 and 60 cases. However there was a distinct lack of standardization in the variables/outcome measures used, case selection, prior experience, and supervision of participating surgeons and a range of statistical analyses to compute LCs was noted. Conclusion. LCs in cardiothoracic and vascular procedures are hugely variable depending on the procedure type, outcome measures, level of prior experience, and methods/statistics used. Uniformity in methods, variables, and statistical analysis is needed to derive meaningful comparisons of LCs. Acknowledgment and application of learning processes other than those reliant on volume–outcomes relationship will benefit LC research and training of surgeons. 相似文献
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Umair Kamran Jennifer Towey Amardeep Khanna Abhishek Chauhan Neil Rajoriya rew Holt 《World journal of gastroenterology : WJG》2020,26(22):2916-2930
Malnutrition encompassing both macro-and micro-nutrient deficiency,remains one of the most frequent complications of alcohol-related liver disease(ArLD).Protein-energy malnutrition can cause significant complications including sarcopenia,frailty and immunodepression in cirrhotic patients.Malnutrition reduces patient's survival and negatively affects the quality of life of individuals with ArLD.Moreover,nutritional deficit increases the likelihood of hepatic decompensation in cirrhosis.Prompt recognition of at-risk individuals,early diagnosis and treatment of malnutrition remains a key component of ArLD management.In this review,we describe the pathophysiology of malnutrition in ArLD, review the screening tools available for nutritional assessment and discuss nutritional management strategies relevant to the different stages of ArLD,ranging from acute alcoholic hepatitis through to decompensated end stage liver disease. 相似文献
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Life expectancy with and without dementia in persons with mild cognitive impairment in the community
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Ayse Irem Kilic Kamran Mirza Swati Mehrotra Stefan E. Pambuccian 《Diagnostic cytopathology》2019,47(7):725-732
Undifferentiated malignant SMARCA4‐deficient neoplasms are rare, recently characterized, high grade, potentially lethal malignancies. Such tumors are characterized by the loss of BRG1 encoded by SMARCA4, a key component of the Switch/Sucrose Non‐Fermenting (SWI/SNF) chromatin remodeling complex. As this complex, also referred as BAF (BRG1/BRM associated factors) complex, is involved in the epigenetic control of hundreds of genes, including those involved in lineage‐specific differentiation, BAF‐deficient tumors, show minimal or no differentiation and are difficult to classify. Their fine needle aspiration (FNA) cytologic features are still poorly defined. Here, we describe a 70‐year‐old man who presented with thickening of the wall of the distal esophagus and stomach and multiple liver and lung lesions. Liver FNA showed relatively uniform dispersed malignant cells with high nucleus: cytoplasm ratio, scant microvacuolated cytoplasm, eccentric nuclei and prominent nucleoli. Mitoses, necrotic debris, nuclear streak artifact, “ghost cells” and focal rhabdoid cytoplasmic inclusions were also present. The liver core biopsy and GI biopsies demonstrated sinusoidal and respectively submucosal involvement by a high grade undifferentiated malignant neoplasm. The tumor cells were negative for all applied markers on immunohistochemistry and flow cytometry, and only showed CD138 and weak PAX5 staining. After an initial diagnosis of hematolymphoid neoplasm, additional stains showed intact INI1 protein and loss of BRG1 protein immunoexpression, establishing the accurate diagnosis. This case highlights the difficulties and potential pitfalls encountered in the FNA diagnosis of BAF‐deficient tumors, the accurate diagnosis of which is important due to their lack of response to conventional therapy and potential response to targeted therapy. 相似文献