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991.
Dietary sources of polyphenols, which are derivatives and/or isomers of flavones, isoflavones, flavonols, catechins and phenolic acids, possess antioxidant properties and therefore might be important in preventing oxidative‐stress‐induced platelet activation and attenuating adverse haemostatic function. Free radicals, including reactive oxygen and nitrogen species, promote oxidative stress, leading to platelet hyperactivation and the risk of thrombosis. The consumption of antioxidant/polyphenol rich foods might therefore impart anti‐thrombotic and cardiovascular protective effects via their inhibition of platelet hyperactivation or aggregation. Most commonly‐used anti‐platelet drugs such as aspirin block the cyclooxygenase (COX)‐1 pathway of platelet activation, similar to the action of antioxidants with respect to neutralising hydrogen peroxide (H2O2), with a similar effect on thromboxane production via the COX‐1 pathway. Polyphenols also target various additional platelet activation pathways (e.g. by blocking platelet‐ADP, collagen receptors); thus alleviating fibrinogen binding to platelet surface (GPIIb‐IIIa) receptors, reducing further platelet recruitment for aggregation and inhibiting platelet degranulation. As a result of the ability of polyphenols to target additional pathways of platelet activation, they may have the potential to substitute or complement currently used anti‐platelet drugs in sedentary, obese, pre‐diabetic or diabetic populations who can be resistant or sensitive to pharmacological anti‐platelet therapy. 相似文献
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目的探讨单采血小板与混合血小板在血液采集制备过程中细菌污染的危险程度,为血小板的采集制备过程中改良工艺,提高输血安全性提供可靠数据。方法采用生物梅里埃公司生产的BaeT/Alert3D全自动细菌培养仪及应用需氧瓶(BPA Culture Bottle)、厌氧瓶(BPN Culture Bottle)对5210例单采血小板,1653例混合血小板进行了细菌培养,细菌培养阳性者转种,转种阳性者进行细菌鉴定。结果在5210例单采血小板细菌培养经确定阳性6例,阳性率为1.15‰;1653例混合血小板中细菌培养经确定阳性10例,阳性率6.05‰。结论混合血小板细菌培养阳性率(6.05‰)高于单采血小板(1.15‰),两者比较差异有统计学意义(P〈0.01);血小板细菌污染情况仍然严峻,应引起注意。 相似文献
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《Pathology, research and practice》2020,216(2):152724
Anaplastic lymphoma kinase negative systemic anaplastic large cell lymphoma (ALK-ALCL) is a CD30+ T-cell malignant lymphoma which may involve both lymph nodes and extranodal tissues, showing important clinical differences from ALK-positive ALCL (ALK + ALCL). ALK- ALCL is considered a specific entity by the 2016 World Health Organization (WHO) classification of hematolymphoid neoplasms.We describe an exceptional case of ALK- ALCL with a striking “Hodgkin-like” cytomorphology and a very uncommon nuclear expression of PAX5. 相似文献
997.
Calixto‐Hope G. Lucas Javier E. Villanueva‐Meyer Nicholas Whipple Nancy Ann Oberheim Bush Tabitha Cooney Susan Chang Michael McDermott Mitchel Berger Elaine Cham Peter P. Sun Angelica Putnam Hong Zhou Robert Bollo Samuel Cheshier Matthew M. Poppe Kar‐Ming Fung Sarah Sung Chad Glenn Xuemo Fan Serguei Bannykh Jethro Hu Moise Danielpour Rong Li Elizabeth Alva James Johnston Jessica Van Ziffle Courtney Onodera Patrick Devine James P. Grenert Julieann C. Lee Melike Pekmezci Tarik Tihan Andrew W. Bollen Arie Perry David A. Solomon 《Brain pathology (Zurich, Switzerland)》2020,30(3):479-494
“Myxoid glioneuronal tumor, PDGFRA p.K385‐mutant” is a recently described tumor entity of the central nervous system with a predilection for origin in the septum pellucidum and a defining dinucleotide mutation at codon 385 of the PDGFRA oncogene replacing lysine with either leucine or isoleucine (p.K385L/I). Clinical outcomes and optimal treatment for this new tumor entity have yet to be defined. Here, we report a comprehensive clinical, radiologic, and histopathologic assessment of eight cases. In addition to its stereotypic location in the septum pellucidum, we identify that this tumor can also occur in the corpus callosum and periventricular white matter of the lateral ventricle. Tumors centered in the septum pellucidum uniformly were associated with obstructive hydrocephalus, whereas tumors centered in the corpus callosum and periventricular white matter did not demonstrate hydrocephalus. While multiple patients were found to have ventricular dissemination or local recurrence/progression, all patients in this series remain alive at last clinical follow‐up despite only biopsy or subtotal resection without adjuvant therapy in most cases. Our study further supports “myxoid glioneuronal tumor, PDGFRA p.K385‐mutant” as a distinct CNS tumor entity and expands the spectrum of clinicopathologic and radiologic features of this neoplasm. 相似文献
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