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21.
We report the fatal course of a left atrial myxoma: its systemic embolization to the coronary, cerebral, renal, and peripheral vascular beds in a 39-year-old woman resulted in rapid clinical deterioration, multiorgan failure, and death. Among reported cases of left atrial myxoma, this degree of embolic burden is exceedingly rare. In addition to reporting the patient''s case, we discuss the presentation and diagnosis of possible intracardiac sources of systemic emboli.Key words: Cerebral arteries/pathology, embolism/diagnosis, fatal outcome, heart atria/pathology, heart neoplasms/complications, myocardial infarction/etiology, myxoma/complications/diagnosis/epidemiology/pathologyWhen a patient presents with simultaneous vascular insults that involve multiple organ systems, a catastrophic clinical outcome can result. We report the case of a patient who had symptoms of systemic embolization, and we discuss the presentation, recognition, and treatment of the left atrial myxoma that was responsible.  相似文献   
22.
Correction for ‘Acridinedione as selective flouride ion chemosensor: a detailed spectroscopic and quantum mechanical investigation’ by Nafees Iqbal et al., RSC Adv., 2018, 8, 1993–2003.

The authors regret that the interpretation of the fluorescence spectra of compound 7i published in the original article was incorrect. In the original article, it was reported that upon excitation at 380 nm, the fluorescence spectrum of compound 7i showed two emission bands at 450 nm and 770 nm (Fig. 5b of the original article). The signal at 770 nm (previously reported as an emission band), is instead a second order diffraction (an artefact of diffraction grating/spectrofluorometer monochromator), as revealed from the literature.1,2 The authors thank a reader for highlighting this mistake.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.  相似文献   
23.
Biological nanopores are revolutionizing human health by the great myriad of detection and diagnostic skills. Their nano-confined area and ingenious shape are suitable to investigate a diverse range of molecules that were difficult to identify with the previous techniques. Additionally, high throughput and label-free detection of target analytes instigated the exploration of new bacterial channel proteins such as Fragaceatoxin C (FraC), Cytolysin A (ClyA), Ferric hydroxamate uptake component A (FhuA) and Curli specific gene G (CsgG) along with the former ones, like α-hemolysin (αHL), Mycobacterium smegmatis porin A (MspA), aerolysin, bacteriophage phi 29 and Outer membrane porin G (OmpG). Herein, we discuss some well-known biological nanopores but emphasize on MspA and compare the effects of site-directed mutagenesis on the detection ability of its mutants in view of the surface charge distribution, voltage threshold and pore–analyte interaction. We also discuss illustrious and latest advances in biological nanopores for past 2–3 years due to limited space. Last but not the least, we elucidate our perspective for selecting a biological nanopore and propose some future directions to design a customized nanopore that would be suitable for DNA sequencing and sensing of other nontrivial molecules in question.

Future of nanopore DNA sequencing: schematic illustration shows the future of nanopore DNA sequencing by using a customized biological nanopore with appropriate fabrication.  相似文献   
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Bone marrow transplantation (BMT) is a successful and recognised treatment option for patients with a number of haematological and non-haematological malignant and non-malignant conditions. Pulmonary complications both infectious and non-infectious are common after BMT. Multiple factors are thought to contribute to pulmonary complications, including the type and duration of immunological defects produced by the underlying disease and treatment, the development of graft-versus-host disease (GVHD), and the conditioning regimens employed. These complications are classified as early or late, depending on whether they occur before or after 100 days from transplantation. Early non-infectious pulmonary complications typically include pulmonary oedema, upper airway complications, diffuse alveolar haemorrhage, cytolytic thrombi, and pleural effusion. Bronchiolitis obliterans, veno-occlusive disease, and secondary malignancies occur late after BMT. Idiopathic pneumonia syndrome, GVHD, and radiation induced lung injury can occur in early or late period after BMT.  相似文献   
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To evaluate the role of ras activation and human papillomavirus (HPV) infection in laryngeal carcinoma, we analyzed tumor DNA from 43 cases, including 25 primary laryngeal tumors, 12 lymph-node and one skin metastases, and 5 recurrent laryngeal carcinomas. Thirteen normal laryngeal tissues and 7 benign laryngeal nodule biopsy specimens along with normal tissue surrounding laryngeal carcinoma in 2 cases were also included. The polymerase-chain-reaction technique was used to amplify DNA fragments containing codon 12 and 61 of H-, K- and N-ras, also HPV 16, 18 and 33 DNA, subsequently hybridized with sequence-specific oligonucleotides. DNA samples from 22 patients with laryngeal carcinoma revealed ras mutations (18 in N-ras codon 12, 6 in H-ras codon 61, and 3 in K-ras codon 61). Likewise, HPV DNA was found in 16 cases (HPV 16, 18 and 33 in 3 cases, 14 cases and 1 case respectively). ras mutations were significantly higher in metastatic tumors (10 of 13 cases) than in primary (11 of 25 cases) and recurrent laryngeal carcinomas (1 of 5 cases). HPV DNA was detected in 60% of recurrent, 44% of primary and 15% of metastatic tumors. Only 2 of the 13 normal laryngeal tissues and 1 out of 7 laryngeal nodule specimens were found to contain HPV DNA. These results suggest that ras activation, especially in N-ras codon 12.1 (GGT → AGT) and HPV infection are 2 important factors in (multistage) laryngeal carcinogenesis. The ras mutation may be associated with metastatic ability of the tumor.  相似文献   
29.
Summary— This paper is a compendium of exact and asymptotic formulas and tables for calculating the sample size in a clinical trial for a matched-pair design involving a dichotomous outcome. Formulas for calculating power given the sample size are also given.  相似文献   
30.
A 16-month-old infant with hepatic fibrosis, cholestasis, and chronic jaundice had signs of vitamin E deficiency, including mild acanthocytosis, thrombocytosis, increased peroxide haemolysis, and absent serum vitamin E. Abormal prothrombin consumption and platelet restocetin aggregation suggested the presence of defective platelet function, and correction studies indicated that this was due to a plasma defect. The abnormality was corrected by treatment with vitamin E, and the findings suggest a possible role of this vitamin in platelet reactions.  相似文献   
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