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71.
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David W. Ellison Kenneth D. Aldape David Capper Maryam Fouladi Mark R. Gilbert Richard J. Gilbertson Cynthia Hawkins Thomas E. Merchant Kristian Pajtler Sriram Venneti David N. Louis 《Brain pathology (Zurich, Switzerland)》2020,30(5):863-866
Advances in our understanding of the biological basis and molecular characteristics of ependymal tumors since the latest iteration of the World Health Organization (WHO) classification of CNS tumors (2016) have prompted the cIMPACT‐NOW group to recommend a new classification. Separation of ependymal tumors by anatomic site is an important principle of the new classification and was prompted by methylome profiling data to indicate that molecular groups of ependymal tumors in the posterior fossa and supratentorial and spinal compartments are distinct. Common recurrent genetic or epigenetic alterations found in tumors belonging to the main molecular groups have been used to define tumor types at intracranial sites; C11orf95 and YAP1 fusion genes for supratentorial tumors and two types of posterior fossa ependymoma defined by methylation group, PFA and PFB. A recently described type of aggressive spinal ependymoma with MYCN amplification has also been included. Myxopapillary ependymoma and subependymoma have been retained as histopathologically defined tumor types, but the classification has dropped the distinction between classic and anaplastic ependymoma. While the cIMPACT‐NOW group considered that data to inform assignment of grade to molecularly defined ependymomas are insufficiently mature, it recommends assigning WHO grade 2 to myxopapillary ependymoma and allows grade 2 or grade 3 to be assigned to ependymomas not defined by molecular status. 相似文献
73.
Tariq A. Madani El-Tayb M. E. Abuelzein Esam I. Azhar Hussein M. S. Al-Bar 《Archives of virology》2014,159(10):2687-2691
The physico-chemical and biological characteristics of Alkhumra hemorrhagic fever virus (AHFV) are not yet known. The present study describes the thermal stability of this virus at different temperatures for different periods. The kinetics of thermal inactivation were studied, linear regressions were plotted, the Arrhenius equation was applied, and the activation energy was calculated accordingly. Titers of the residual virus were determined in median tissue culture infective dose (TCID50), and the rate of destruction of infectivity at various temperatures was determined. Infectivity of AHFV was completely lost upon heating for 3 minutes at 60 °C and for 30 min at 56 °C. However, the virus could maintain 33.2 % of its titer after heating for 60 min at 45 °C and 32 % of its titer after heating for 60 min at 50 °C. In conclusion, AHFV is thermo-labile, and its inactivation follows first-order kinetics. 相似文献
74.
Lin Xu Umair Azhar Zizhao Chen Qingxia Niu Jian Chen Xiaohan Zhao Shuxiang Zhang Chuanyong Zong 《RSC advances》2020,10(6):3416
Smart surfaces with controlled topography show broad and fantastic applications in optics, biology and information science. Herein, we report a simple visible-light-illumination approach to fabricate a smart wrinkle-forming surface with photo-controllable hierarchical surface patterns as well as rewritable high-resolution patterns of information by using an azobenzene-containing epoxy-based oligomer. The epoxy oligomer was synthesized via the ring-opening polymerization of bisphenol AF diglycidyl ether (BADFGE) with p-aminoazobenzene (AAB) and characterized using FTIR, 1H NMR and 19F NMR spectroscopies. When the epoxy oligomer film was deposited on an elastic substrate, the formation of surface wrinkles was triggered via a circulation of heating/cooling and photo-tailored due to photo-softening together with the release of stress induced by cycles of photoisomerization of azobenzene in the oligomer. The wrinkles in selectively light-exposed regions could be photo-erased within tens of seconds, yielding a different pattern of information. The high-resolution photo-printed images were shown to be rewritable for multiple cycles and legible for over 3 months in dark ambient conditions. The as-formed epoxy oligomer wrinkle-forming surface was found to be inexpensive and its fabrication was easily amenable to scale up, indicating its great potential as ink-free light printable media for rewritable information storage.A novel rapidly responsive media for rewritable information storage comprised of an azobenzene-containing epoxy-based oligomer displaying surface wrinkling was developed. 相似文献
75.
Monire Mirzaei Abbas Eshraghi Mahdiieh Ghoddoosi Maedeh Alsadat Fatemi Azhar Eshraghi Sara Shenavaei Danial Fazilatpanah 《Clinical Case Reports》2022,10(4)
We reported a female presented with an initial diagnosis of metastatic axillary lymph‐node carcinoma that comprehensive assessments revealed a definitive diagnosis of high‐grade serous ovarian carcinoma as the primary tumor. 相似文献
76.
Azhar Equbal Mohammad Ali Md. Asif Equbal S. C. Srivastava Zahid A. Khan Md. Israr Equbal Irfan Anjum Badruddin Khalid Mohamed El-Hady Sarfaraz Kamangar 《Materials》2022,15(7)
In this study, compacted hematite (Fe2O3) preforms were made and sintered at various temperatures, such as 1250 °C and 1300 °C, using both conventional and microwave sintering methods. The density, porosity, microhardness, cold crushing strength, microphotographs, and X-ray diffraction (XRD) analysis of the sintered preforms were used to evaluate the performance of the two sintering methods. It was found that microwave sintered preforms possessed lesser porosity and higher density than conventionally sintered preforms owing to uniform heating of the powdered ore in microwave sintering method. Furthermore, it was also observed that microwave sintered preforms exhibited relatively higher cold crushing strength and hardness than conventionally sintered preforms. Thus, the overall results revealed that microwave sintering yielded better properties considered in the present study. 相似文献
77.
R. Lane Smith Thomas C. Merchant David J. Schurman 《Arthritis \u0026amp; Rheumatology》1982,25(4):441-446
Effects of Escherichia coli and Staphylococcus aureus on cartilage and chondrocytes in culture are reported. Under these conditions, bacterial effects on cartilage degradation and cell viability are measured in the absence of inflammation. E coli causes a 28% loss and S aureus an 83% loss of cartilage glycosaminoglycan within 48 hours. Collagen content is unchanged. Both bacterial species induce chondrocyte death in explants and in monolayers within 48 hours. Bacterial effects on glycosaminoglycans and cell viability do not result from depletion of nutrients from the culture medium. Serum in the culture media inhibits the bacterial effects on cartilage degradation but does not prevent cell death. 相似文献
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80.
Daniel R. Budman E. Bruce Merchant Alfred D. Steinberg Bernard Doft M. Eric Gershwin Elaine Lizzio J. Patton Reeves 《Arthritis \u0026amp; Rheumatology》1977,20(3):829-833
Thirty-seven patients with criteria for systemic lupus erythematosus (SLE) and 18 normal controls were studied for their spontaneous background IgM antibody plaque-forming cell number to specific chemical haptens. Active SLE patients had significantly more plaque-forming cells in their peripheral blood to a total of five chemical determinants than did patients with inactive disease or controls. This increased number of plaque forming-cells correlated with depressed serum C3 levels by Spearman rank-order analysis. The finding of elevated numbers of spontaneous IgM plaque-forming cells to defined chemical haptens supports the concept that active SLE demonstrates a generalized increase in B-cell activity toward a variety of antigens. 相似文献