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161.
A patient with pheochromocytoma presented striking electrocardiographic changes mimicking ischemic heart disease at one time and acute pulmonary embolism at other times. Diffuse left ventricular hypokinesia was demonstrated in the presence of normal coronary arteries. Following removal of the pheochromocytoma, the electrocardiographic abnormalities disappeared. 相似文献
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163.
Tall Abdoulaye Faraji Sheida Diallo Abdou K. Mohammadian Navid Erouel Mohsen Seck Mané Saadi Meriem Khirouni Kamel Majewski Leszek A. 《Journal of Materials Science: Materials in Electronics》2022,33(19):15283-15295
Journal of Materials Science: Materials in Electronics - Nature provides a wide range of dielectric biopolymers that can be used in electronic devices. In this work, organic field-effect... 相似文献
164.
Emily E. F. Brown Reza Rezaei Taylor R. Jamieson Jaahnavi Dave Nikolas T. Martin Ragunath Singaravelu Mathieu J. F. Crupi Stephen Boulton Sarah Tucker Jessie Duong Joanna Poutou Adrian Pelin Hamed Yasavoli-Sharahi Zaid Taha Rozanne Arulanandam Abera Surendran Mina Ghahremani Bradley Austin Chantal Matar Jean-Simon Diallo John C. Bell Carolina S. Ilkow Taha Azad 《International journal of molecular sciences》2021,22(5)
Despite sequence similarity to SARS-CoV-1, SARS-CoV-2 has demonstrated greater widespread virulence and unique challenges to researchers aiming to study its pathogenicity in humans. The interaction of the viral receptor binding domain (RBD) with its main host cell receptor, angiotensin-converting enzyme 2 (ACE2), has emerged as a critical focal point for the development of anti-viral therapeutics and vaccines. In this study, we selectively identify and characterize the impact of mutating certain amino acid residues in the RBD of SARS-CoV-2 and in ACE2, by utilizing our recently developed NanoBiT technology-based biosensor as well as pseudotyped-virus infectivity assays. Specifically, we examine the mutational effects on RBD-ACE2 binding ability, efficacy of competitive inhibitors, as well as neutralizing antibody activity. We also look at the implications the mutations may have on virus transmissibility, host susceptibility, and the virus transmission path to humans. These critical determinants of virus–host interactions may provide more effective targets for ongoing vaccines, drug development, and potentially pave the way for determining the genetic variation underlying disease severity. 相似文献
165.
The design of reverse logistics and remanufacturing processes and the recovery of end-of-life products have been well-studied in the literature. Quality, reliability, maintenance and warranty for recovered products and the remanufacturing activities that extend their life are integral issues in reverse logistics. This paper reviews recent and relevant literature on these issues in closed-loop supply chains, with a focus on remanufactured or second-hand products. The published literature is first classified into domain areas of research and practice. The wide array of mathematical tools and techniques used in the literature are then identified and mapped. Finally, the findings are summarised and the main research gaps are highlighted. 相似文献
166.
Gregory Zacharewicz Saikou Diallo Yves Ducq Carlos Agostinho Ricardo Jardim-Goncalves Hassan Bazoun Zhongjie Wang Guy Doumeingts 《Information Systems and E-Business Management》2017,15(2):229-256
Enterprise businesses are more than ever challenged by competitors that frequently refine and tailor their offers to clients. In this context, enterprise information systems (EIS) are especially important because: (1) they remain one of the last levers to increase the performance and competitiveness of the enterprise, (2) we operate in a business world where the product itself has reached a limit of performance and quality due to uniform capacity of industrial tools in a globalized economy and (3) the EIS can increase the product value thanks to additional digital services (built on data associated to the product) in order to meet and fit better client’s needs. However, the use of EISs reaches a limit in collaborative environments because enterprises management methods diverge and EISs are mainly inflexible resource packages that are not built with an interoperability objective. Consequently, we need to make EISs interoperable in order to achieve the needed gains competitiveness and performance. This paper contribution can be summarized as follows: (1) it relates existing work and it examines barriers that, at the moment, are preventing further improvements due to current methodological and technological limits, and (2) it proposes a conceptual framework and five challenges that model based approaches must overcome to achieve interoperability between EIS in the near and long term. 相似文献
167.
NARESH K. SINHA ABHIJIT SEN ROGER H. Y. TO 《International journal of systems science》2013,44(4):373-382
Two digital methods are proposed for the solution of the time-domain approximation problem. Tho first method, based on a reeursivo algorithm for tho matrix pseudo-iriverso, determines the pulse transfer function of a discrete-timo system of a prescribed order providing the best fit in tho least squares sense at tho samplo points. Tho continuous-time system transfer function is then derived by using a simple transformation provided that tho sampling frequence oxeeeds tho Nyquist rate. Tho method is direct and computationally efficient. The second method is based on using an offieiont gradient search algorithm providing the best fit in the least pti sense at tho samplo points. A number of examples illustrato the methods 相似文献
168.
The effects of ginsenoside-Rh1 and Rh2 in the induction of nitric oxide (NO) synthesis by IFN-gamma plus LPS were investigated using murine peritoneal macrophages. The NO production from rIFN gamma plus LPS-treated macrophages was markedly reduced by ginsenoside-Rh1 or Rh2 in a dose dependent manner, but had no inhibitory effects by ginsenoside-Rb1, Rc or Re. In addition, treatment of the cells with ginsenoside-Rh2 6 hr before the stimulation with IFN-gamma plus LPS showed more inhibitory effect than the treatment with ginsenoside-Rh2 6 hr after or simultaneously with the stimulation with IFN-gamma plus LPS in the NO production. Ginsenoside-Rh2 also effectively inhibited IFN-gamma induced NO production when the cells were treated with IFN-gamma 6 hr after the treatment with ginsenoside-Rh2. Our findings suggest that this phenomenon might be caused by inhibition of priming signal such as IFN-gamma for the synergistic induction of NO synthesis. 相似文献
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O Faye P Fofana J Correa O Gaye T Dieng Y Dieng IB Bah O N''Dir S Diallo 《Canadian Metallurgical Quarterly》1998,91(2):169-172
To determine the origin and nature of mucinlike material in fine-needle aspiration (FNA) smears of the breast in noncancerous breast lesions, we studied breast FNA smears from four patients. All smears contained epithelial cells floating in a mucinlike background, which raised suspicion for mucinous (colloid) carcinoma. Mucicarmine stain was performed on one smear from each case. Subsequent tissue biopsy specimens were studied using mucicarmine, periodic acid-Schiff with and without diastase, and alcian blue stains at pH 2.7 and 0.9 on selected tissue sections. Correlation of the cytologic and histologic findings of each lesion was performed. The mucinlike background in all four FNA smears stained strongly with mucicarmine. Corresponding biopsy specimens revealed pseudoangiomatous hyperplasia in the first case, fibroadenoma and atypical ductal hyperplasia in the second, benign phyllodes tumor in the third, and fibroadenoma in the fourth. Each lesion in cases 1 to 3 was associated closely with fibrocystic changes. In case 4, cystic changes were located within the fibroadenoma. On tissue sections of all four cases, the cyst contents and 10% to 50% of normal lobule and duct contents stained with mucicarmine, indicating that the cyst contents were the most probable source of mucin in the FNA smears. The presence of pools of mucicarmine-positive material in FNA smears of the breast is not an exclusive feature of mucinous carcinoma; mucicarmine-positive mucin can arise from benign cystic changes as well as from normal lobules and ducts. 相似文献