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31.
Cardiac myxomas are benign primer cardiac tumors of the heart. They can be fatal with a thromboembolic presentation. Myocardial infarction is one of these unusual thromboembolic presentations. We report a patient who presented with cardiac arrest due to ventricular fibrillation related to myocardial infarction. After successful resuscitation, coronary angiography and transthoracic echocardiography were performed. A left atrial mass was observed and interpreted as a possible cause of coronary embolism leading to myocardial infarction. After surgical excision, the pathological examination confirmed myxoma, which was the essential cause of the tendency to arterial embolism.  相似文献   
32.
Solid organ transplant (SOT) recipients may be at risk for severe COVID-19. Data on the clinical course of COVID-19 in immunosuppressed patients are limited, and the effective treatment strategy for these patients is unknown. We describe our institutional experience with COVID-19 in SOT. Demographic, clinical, and treatment data were extracted from the electronic patient files. A total of 23 SOT transplant recipients suffering from COVID-19 were identified (n = 3 heart; n = 15 kidney; n = 1 kidney-after-heart; n = 3 lung, and n = 1 liver transplant recipient). The presenting symptoms were similar to nonimmunocompromised patients. Eighty-three percent (19/23) of the patients required hospitalization, but only two of these were transferred to the intensive care unit. Five patients died from COVID-19; all had high Clinical Frailty Scores. In four of these patients, mechanical ventilation was deemed futile. In 57% of patients, the immunosuppressive therapy was not changed and only three patients were treated with chloroquine. Most patients recovered without experimental antiviral therapy. Modification of the immunosuppressive regimen alone could be a therapeutic option for SOT recipients suffering from moderate to severe COVID-19. Pre-existent frailty is associated with death from COVID-19.  相似文献   
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Lung mucociliary clearance rates were measured in 11 patients with rheumatoid disease and found to be unaltered when compared with those of a group of matched control subjects. The results are discussed in relation to the increased incidence of respiratory infection in patients with rheumatoid disease and also to the recently reported finding of increased airways obstruction in these patients.  相似文献   
35.

Background

Although ischemic stroke is a well-known complication of cardiovascular surgery it has not been extensively studied in patients undergoing noncardiac surgery. The aim of this study was to assess the predictors and outcomes of perioperative acute ischemic stroke (PAIS) in patients undergoing noncardiothoracic, nonvascular surgery (NCS).

Methods

We prospectively evaluated patients undergoing NCS and enrolled patients older than 18 years who underwent an elective, non-daytime, open surgical procedure. Electrocardiography and cardiac biomarkers were obtained 1 day before surgery, and on postoperative days 1, 3 and 7.

Results

Of the 1340 patients undergoing NCS, 31 (2.3%) experienced PAIS. Only age (odds ratio [OR] 2.5, 95% confidence interval [CI] 1.01–3.2, p < 0.001) and preoperative history of stroke (OR 3.6, 95% CI 1.2–4.8, p < 0.001) were independent predictors of PAIS according to multivariate analysis. Patients with PAIS had more cardiovascular (51.6% v. 10.6%, p < 0.001) and noncardiovascular complications (67.7% v. 28.3%, p < 0.001). In-hospital mortality was 19.3% for the PAIS group and 1% for those without PAIS (p < 0.001).

Conclusion

Age and preoperative history of stroke were strong risk factors for PAIS in patients undergoing NCS. Patients with PAIS carry an elevated risk of perioperative morbidity and mortality.  相似文献   
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There is increasing concern regarding alleviating world energy demand by determining an alternative to petroleum-derived fuels due to the rapid depletion of fossil fuels, rapid population growth, and urbanization. Biodiesel can be utilized as an alternative fuel to petroleum-derived diesel for the combustion engine. At present, edible crops are the primary source of biodiesel production. However, the excessive utilization of these edible crops for large-scale biodiesel production might cause food supply depletion and economic imbalance. Moreover, the utilization of edible oil as a biodiesel feedstock increases biodiesel production costs due to the high price of edible oils. A possible solution to overcome the existing limitations of biodiesel production is to utilize non-edible crops oil as a feedstock. The present study was conducted to determine the possibility and challenges of utilizing non-edible oil as a potential feedstock for biodiesel production. Several aspects related to non-edible oil as a biodiesel feedstock such as overview of biodiesel feedstocks, non-edible oil resources, non-edible oil extraction technology, its physicochemical and fatty acid properties, biodiesel production technologies, advantages and limitation of using non-edible oil as a feedstock for biodiesel production have been reviewed in various recent publications. The finding of the present study reveals that there is a huge opportunity to utilize non-edible oil as a feedstock for biodiesel production.

There is increasing concern regarding alleviating world energy demand by determining an alternative to petroleum-derived fuels due to the rapid depletion of fossil fuels, rapid population growth, and urbanization.  相似文献   
39.
Correction for ‘Development and in vitro evaluation of κ-carrageenan based polymeric hybrid nanocomposite scaffolds for bone tissue engineering’ by Muhammad Umar Aslam Khan et al., RSC Adv., 2020, 10, 40529–40542. DOI: 10.1039/D0RA07446B.

The authors regret errors in Fig. 9 in the original article. The corrected Fig. 9 is shown below where all three +ive control panels and the 72 h CG-g-Aac-2 panel have been replaced.Open in a separate windowFig. 9Cell morphology of MC3T3-E1 against +ive control and all scaffold samples (CG-g-AAc1, CG-g-AAc2 and CG-g-AAc3) under standard in vitro conditions. The red arrows show thread-like morphology and the yellow arrows exhibits well-grown morphology of the cells.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.  相似文献   
40.
Spinal metastasis of occult lung carcinoma causing cauda equina syndrome.   总被引:1,自引:0,他引:1  
Cauda equina syndrome (CES) may be caused by tumor, herniated disc, trauma and spinal infections. However, CES due to occult lung cancer has not been reported in the literature. A 50-year-old man presented with a subacute CES caused by an intradural metastasis of an adenocarcinoma of the lung to the lumbosacral cauda fibers. His lumbosacral magnetic resonance imaging (MRI), showed a well-demarcated, intradural extramedullary mass lesion resembling a neurinoma at the L4/5 level. The patient underwent an L4-L5 laminectomy. The operative findings were also suggestive of neurinoma with involvement of three nerve roots, and a well-demarcated tumor without infiltration into the subarachnoid space. Although the findings of the operation were suggestive of neurinoma, final pathological diagnosis revealed metastatic carcinoma. Immunohistochemistry revealed clear cell adenocarcinoma metastasis. Chest X-ray and high resolution contrasted pulmonary computed tomography were normal. Positron emission tomography (PET) showed a lung mass, at the left apex. The patient was treated with chemotherapy and post-operative spinal radiotherapy was also performed. The CES resolved after the operation and the patient was followed up for 2 years with no recurrence. MRI of intradural cauda equina metastasis may be similar to that of intradural nerve sheath tumor. Surgery and postoperative radiotherapy may be effective for the treatment of CES due to lung carcinoma. Definitive diagnosis is by histopathological examination with immunohistochemistry. If the primary cancer cannot be detected by conventional radiological techniques, PET may be helpful.  相似文献   
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