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排序方式: 共有8034条查询结果,搜索用时 46 毫秒
1.
Syed M. Gilani Muhammad Khan Andrea Barbieri Manju L. Prasad 《Diagnostic Histopathology》2021,27(6):263-271
Anaplastic thyroid carcinoma (ATC) is an aggressive thyroid malignancy with high mortality rate. This malignancy arises in thyroid follicular cells either denovo or with an associated differentiated thyroid carcinoma component. Clinically, it usually presents as a rapidly enlarging mass, pain and locally compressive symptoms. Histopathologic variability and heterogeneity often pose diagnostic challenges, especially in scant and paucicellular specimens. This article describes the clinical, histopathologic and molecular features of ATC and also addresses the associated diagnostic limitations and challenges. 相似文献
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Muhammad I. Zafar Jiequn Han Xu-Hui Zhou & Heng Xiao 《Communications In Computational Physics》2022,32(2):336-363
Partial differential equations (PDEs) play a dominant role in the mathematical modeling of many complex dynamical processes. Solving these PDEs often requires
prohibitively high computational costs, especially when multiple evaluations must be
made for different parameters or conditions. After training, neural operators can provide PDEs solutions significantly faster than traditional PDE solvers. In this work,
invariance properties and computational complexity of two neural operators are examined for transport PDE of a scalar quantity. Neural operator based on graph kernel network (GKN) operates on graph-structured data to incorporate nonlocal dependencies.
Here we propose a modified formulation of GKN to achieve frame invariance. Vector
cloud neural network (VCNN) is an alternate neural operator with embedded frame
invariance which operates on point cloud data. GKN-based neural operator demonstrates slightly better predictive performance compared to VCNN. However, GKN requires an excessively high computational cost that increases quadratically with the
increasing number of discretized objects as compared to a linear increase for VCNN. 相似文献
5.
Muhammad Ruslin Jan Wolff Harmas Yazid Yusuf Muhammad Zaifullah Arifin Paolo Boffano Tymour Forouzanfar 《中华创伤杂志(英文版)》2019,22(1):47-50
Purpose
Mild traumatic brain injury (TBI) is common but accurate diagnosis and its clinical consequences have been a problem. Maxillofacial trauma does have an association with TBI. Neuron-specific enolase (NSE) has been developed to evaluate neuronal damage. The objective of this study was to investigate the accuracy of NSE serum levels to detect mild brain injury of patients with sustained maxillofacial fractures during motor vehicle accidents.Methods
Blood samples were drawn from 40 healthy people (control group) and 48 trauma patients who had sustained isolated maxillofacial fractures and mild brain injury in motor vehicle accidents. Brain injuries were graded by Glasgow Coma Scale. In the trauma group, correlations between the NSE serum value and different facial fracture sites were also assessed.Results
The NSE serum level (mean ± SD, ng/ml) in the 48 patients with maxillofacial fractures and mild TBI was 13.12 ± 9.68, significantly higher than that measured in the healthy control group (7.72 ± 1.82, p < 0.001). The mean NSE serum level (ng/ml) in the lower part of the facial skeleton (15.44 with SD 15.34) was higher than that in the upper facial part (12.42 with SD 7.68); and the mean NSE level (ng/ml) in the middle-and lower part (11.97 with SD 5.63) was higher than in the middle part (7.88 with SD 2.64).Conclusion
An increase in NSE serum levels can be observed in patients sustained maxillofacial fractures and mild brain injury. 相似文献6.
Monitoring vegetation dynamics using the universal normalized vegetation index (UNVI): An optimized vegetation index-VIUPD 总被引:2,自引:0,他引:2
Lifu Zhang Na Qiao Muhammad Hasan Ali Baig Xin Lv Xuejian Sun 《Remote sensing letters.》2019,10(7):629-638
This paper propose a universal normalized vegetation index (UNVI), which is an improved vegetation index (VI) based on the universal pattern decomposition method (UPDM), termed VIUPD. We also derive new matrices to facilitate convenient calculation of the UNVI based on data from the MODIS and Landsat-TM, ETM, OLI satellite sensors. We compared the performance of the UNVI to the normalized difference vegetation index (NDVI), enhanced vegetation index (EVI) and modified soil adjusted vegetation index 2 (MSAVI2) to estimate the vegetation dynamics (chlorophyll content and leaf area index [LAI]). The results show that the UNVI was more sensitive to vegetation dynamics than the NDVI, EVI and MSAVI2. The UNVI has a higher LAI saturation point than the other three indices. The UNVI can be used to monitor global changes in above ground biomass (AGB) and gross primary production (GPP) with respect to a wide range of vegetation dynamics. 相似文献
7.
Inna Y. Gong Nigel S. Tan Sammy H. Ali Gerald Lebovic Muhammad Mamdani Shaun G. Goodman Dennis T. Ko Andreas Laupacis Andrew T. Yan 《The Canadian journal of cardiology》2019,35(5):653-660
Background
Although it is known that women do not participate in trials as frequently as men, there are limited recent data examining how women recruitment has changed over time.Methods
We conducted MEDLINE search using a validated strategy for randomized trials published in New England Journal of Medicine, Lancet, and Journal of the American Medical Association between 1986 and 2015, and included trials evaluating pharmacologic or nonpharmacologic therapies. We abstracted data on demographics, intervention type, clinical indication, and trial design characteristics, and examined their relationships with women enrollment.Results
In total, 598 trials met inclusion criteria. Women enrollment increased significantly over time (21% between 1986 and 1990 to 33% between 2011 and 2015; Pfor trend < 0.001) and did not differ by journal or funding source. Women enrollment varied with clinical indication, comprising 37% for non–coronary artery disease vascular trials, 30% for coronary artery disease trials, 28% for heart failure trials, and 28% for arrhythmia trials (P < 0.001), which were all significantly lower than the expected proportion in disease populations (P < 0.001). Women enrollment varied with trial type (31%, 29%, and 26% for pharmacologic, device, and procedural trials, respectively; P = 0.001). These findings were corroborated using multivariable analysis. We found significant positive correlations between women enrolled, and mean age and total number of participants. Fewer women were enrolled in trials reporting statistically significant results than those who did not (P = 0.001).Conclusions
Although enrollment of women has increased over time, it remains lower than the relative proportion in the disease population. Future studies should elucidate the reasons for persistent under-representation of women in clinical trials. 相似文献8.
9.
Gerald Chi Adeel Jamil Umer Jamil Muhammad A. Balouch Jolanta Marszalek Farima Kahe 《Clinical and experimental hypertension (New York, N.Y. : 1993)》2019,41(2):160-167
Background: Intensive blood pressure (BP) lowering may offer protective effects against major adverse cardiac event (MACE) but is also associated with a greater risk of a serious adverse event (SAE). The risk-benefit profile of intensive versus standard BP control has not been comprehensively assessed. Methods: Four studies were identified from a systematic literature search for randomized controlled trials comparing intensive versus standard BP lowering that reported both MACE and SAE endpoints. A previously described statistical approach was applied to characterize the efficacy-safety tradeoff of BP control. The bivariate outcome was computed to quantitatively assess the net clinical benefit (NCB) of intensive BP lowering as compared to standard treatment, with positive values indicating increased risks and negative values indicating decreased risks. Results: Data from the SPRINT trial demonstrated that intensive strategy was superior in MACE but inferior in SAE, thereby eroding the NCB (bivariate outcome: 0.33% [?0.50% to 1.21%]). Intensive strategy from the SPS3 trial fulfilled non-inferiority in both MACE and SAE but did not reach a favorable NCB (?1.31% [?2.25% to 0.01%]). The ACCORD trial suggested that intensive strategy was non-inferior in MACE but inferior in SAE (?0.19% [?0.79% to 1.37%]). Results from the VALISH trial were inconclusive for SAE but suggested non-inferiority in MACE (?1.19% [?3.24% to 0.68%]). Conclusions: Compared to the standard blood pressure target, pooled data from randomized controlled trials suggest that intensive strategy did not achieve a net clinical benefit when weighing the benefit of MACE reduction against the risk of SAE under the bivariate framework.Abbreviations: Blood pressure (BP), diastolic blood pressure (DBP), major adverse cardiac event (MACE), net clinical benefit (NCB), serious adverse event (SAE), systolic blood pressure (SBP). 相似文献