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31.
An interesting case of wide QRS tachycardia with right bundle branch block morphology: What is the mechanism? 下载免费PDF全文
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Narrow QRS tachycardia with apparent concentric atrial activation pattern: What is the mechanism? 下载免费PDF全文
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Epoxyeicosatrienoic acids (EETs) are lipid metabolites that are synthesized in vascular endothelial cells. They are released by stimulation of their muscarinic receptors, and induce vaso-relaxation of cerebral blood vessels. In addition, cytochrome P450 epoxygenase enzymes, which catalyze the formation of epoxyeicosatrienoic acids, especially after stimulation by the excitatory neurotransmitter glutamate, are present in astrocytes, an abundant cell type in the brain that extends foot processes onto the cerebral microvessels. Using a modification of an efficient, recently developed, fluorescent assay, we have detected the presence of EETs in endothelial cells cultured from the cortex of rat brains as well as in neonatal astrocytes. We propose that both these cell types provide a dual supply of EETs to increase cerebral blood flow in order to meet systemic as well as localized nutrient demands of cells in the brain. 相似文献
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Markson LE Vollmer WM Fitterman L O'Connor E Narayanan S Berger M Buist AS 《Archives of internal medicine》2001,161(3):379-384
BACKGROUND: Measures of patient satisfaction or dissatisfaction with treatment are increasingly being used as indicators of quality of care. As these measures become more widely used, it is important to know if patient dissatisfaction is associated with important processes or outcomes of medical care. METHODS: Survey of patient-reported asthma management issues using the Asthma Therapy Assessment Questionnaire in a large health maintenance organization in the Pacific Northwest. Associations between patient dissatisfaction with asthma treatment and patient-reported measures of asthma control, patient-provider communication, and belief in asthma medications (self-efficacy) were examined. RESULTS: Of the 5181 adult members with asthma enrolled in the health maintenance organization, 30% indicated dissatisfaction with current treatment. Dissatisfaction was higher among patients with a higher number of asthma control problems, patient-provider communication problems, or belief in medication problems (eg, failure to believe their medications are useful and inability to take asthma medications as directed). The odds of dissatisfaction with treatment were 2.8 (95% confidence interval [CI], 2.4-3.3; P<.001) for asthma control problems, 2.0 (95% CI, 1.6-2.6; P<.001) for communication problems, and 8.0 (95% CI, 6.7-9.5; P<.001) for belief in medication problems compared with patients without these perceived problems. CONCLUSION: Patient dissatisfaction with treatment may be related to important asthma disease management issues. 相似文献
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Rishabh Kumar Prachi Kala Geeta S. Narayanan Bhaskar Vishwanathan Sowmya Narayanan Sanjeet Mandal Arpitha Rao Gangadharappa Gowda 《Brachytherapy》2021,20(1):112-117
PURPOSEImage-guided adaptive brachytherapy (IGABT) recently has shown excellent clinical outcomes with superior local control and less toxicity. For IGABT, T2W (T2-weighted) MRI is the gold standard. However, studies have shown that target delineation with the same results in uncertainties, poor interobserver variabilities, and low conformity indices for high-risk clinical target volume contours. In this study, we investigate the role of diffusion-weighted imaging–derived apparent diffusion coefficient (ADC) maps to aid in IGABT. We also evaluated ADC from the baseline to brachytherapy.Methods and MaterialsThirty selected patients were enrolled for this study, and two MRIs were taken at diagnosis and before brachytherapy. Patients were divided into two groups, Group 1 being patients with parametrial involvement before external beam radiotherapy and no parametrial involvement before brachytherapy. Group 2 included patients with parametrial involvement before external beam radiotherapy and persistent parametrial involvement before brachytherapy. ADC was measured at the center, edge, and 1 cm from the edge.ResultsThe measured ADC increased from diagnosis to brachytherapy, and this increase was more for the patients in Group 1 than in Group 2. The mean TDadc (diagnosis ADC, center), TEadc (tumor edge ADC diagnosis), and T1cmDadc (1 cm from edge at diagnosis) were 0.884, 1.45, and 1.9 × 10?3 mm2/s, respectively. The TBadc (ADC at brachytherapy, center), TEBadc (tumor edge ADC at brachytherapy), and TE1cmBadc (1 cm from edge brachytherapy) were 1.2, 1.8, and 2.3 × 10?3 mm2/s, respectively, p-value <0.00001. No abnormal ADC was present outside the high-risk clinical target volume contours.ConclusionMRI-based IGABT using T2W imaging essentially covers all functionally abnormal zones at brachytherapy. Diffusion-weighted imaging, along with ADC maps, should only be used as a supplement for target delineation. 相似文献
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Cynthia Scott Karthik Ramakrishnan Narayanan Vivek Chandran Saravanan Gurram Prashanthi 《Journal of oral and maxillofacial surgery》2021,79(6):1330.e1-1330.e12
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Damodaran Narayanan Olga K. Weinberg 《International journal of laboratory hematology》2020,42(1):3-15
Acute myeloid leukemia (AML) is a neoplasm of immature myeloid cells and is associated with a wide variety of clinical presentations, morphological features, immunophenotypes, and genetic findings. Recent advances in identification of cytogenetic abnormalities and mutations have provided novel insights into the pathogenesis of AML. Based on the above‐mentioned parameters, the World Health Organization (WHO) classified AML into 25 subtypes, including 2 provisional entities, which differ in prognosis and treatment. In addition, certain mutations are associated with germline predisposition and increase the risk of inherited AML, which warrants family screening. Therefore, precise diagnosis and classification of AML are the most important steps in patient management. Both these steps require incorporation of history, clinical presentation, and laboratory results with studies performed by a pathologist. Pathologist‐initiated studies include morphologic evaluation on the bone marrow aspirate and/or core biopsy, immunophenotyping by flow cytometry and/or immunohistochemistry, cytogenetic analysis by karyotyping and/or fluorescence in situ hybridization, and molecular testing using gene panels and/or next‐generation sequencing. A similar approach is employed during follow‐up of patients after beginning treatment. Here, we describe in detail the various aspects of the workup, including purpose, limitations, and practice guidelines for the different studies. The process of choosing appropriate materials for the different studies is also addressed. We also provide an algorithm for the workup and risk stratification of AML based on guidelines recommended by the WHO, College of American Pathologists, National Comprehensive Cancer Network, American Society of Clinical Oncology, European Society of Medical Oncology, and the European LeukemiaNet. 相似文献
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Gopalan Nair Rajesh Kalathingathodika Sajeer Anishkumar Nair Chakanalil Govindan Sajeev Mangalath Narayanan Krishnan 《Indian heart journal》2014,66(3):370-371
Hammock valve, also known as anomalous mitral arcade is a rare mechanism for congenital mitral insufficiency. We report a case of a two-week-old neonate who presented with features of heart failure and an apical systolic murmur. Echocardiogram showed severe mitral regurgitation and abnormal mitral valve with direct attachment of mitral leaflets to papillary muscle without intervening chordae tendinae, typical of hammock valve. Heart failure was controlled with ionotrpes and diuretics. The literature on the hammock mitral valve is reviewed. 相似文献