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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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Bashir A. Fomda Nazima Abdullah Yawar B. Mir Gulnaz Bashir Asiya Khan Syed M. Qadri Sonaullah Shah 《Indian journal of medical microbiology》2022,40(2):294-298
PurposeThe clinical manifestations of rickettsial diseases mimic other endemic infections with similar presentations thus posing a serious challenge to clinicians for their diagnosis. For the diagnosis of rickettsial disease serological tests like Weil Felix, ELISA and IFA are used. There are limited studies that have evaluated different serological tests for the diagnosis of rickettsial diseases. Therefore, the present study was undertaken to evaluate the ELISA and Weil Felix test for the diagnosis of rickettsial diseases prevalent in this region.MethodsSamples from 281 patients clinically suspected of rickettsial diseases were tested for spotted fever group (SFG), typhus group (TG) and scrub typhus group (STG) by Weil Felix, ELISA and IFA was taken as the gold standard. Baseline titers and cut-off ODs were calculated by taking samples from healthy blood donors.ResultsThe sensitivity, specificity, positive and negative predictive value of Weil Felix test ranged from 30% to 44%, 83.46%–97.86%, 9%–77%, 92–96% respectively. The sensitivity and specificity, positive and negative predictive value of ELISA ranged from 80.77% to 96.15%, 96.33%–98.43%, 70.21%–88.64%, 92.89%–99.60% respectively. Maximum cross-reactions were observed between SFG and STG by the Weil Felix test and between STG and TG by ELISA.ConclusionsELISA was found to be sensitive and specific for the diagnosis of rickettsial diseases. It is easy to perform, does not require a technical expert for result interpretation and a large number of samples can be processed at a time. 相似文献
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目的探讨胆总管结石患者采用内镜逆行胰胆管造影术(ERCP)取石后同期开展胆道支架置入术或开展经内镜鼻胆管引流术(ENBD),对于防范并发症的价值。
方法按照前瞻性研究原则,选择2017年4月至2019年1月新疆医科大学第一附属医院收治的338例胆总管结石患者,随机分为支架组(170例)与引流组(168例)。两组患者均行ERCP治疗,其中引流组术后同期开展ENBD,支架组患者术后开展胆道支架置入术,对比两组患者腹痛评分、并发症发生情况及预后。
结果两组患者术后均未合并严重出血、穿孔或病死,结石完全清除率差异无统计学意义。与支架组相比,引流组术中胰腺管插管次数,术后4 h血淀粉酶水平、高淀粉酶血症、急性胰腺炎以及并发症总发生率更高,差异有统计学意义(P<0.05),术后24、48、72 h不同时点腹痛测评分值居更高水平(P<0.05)。
结论对于胆总管结石行ERCP治疗的患者,术后予以ENBD、胆道支架置入术的结石完全清除效果对比无明显差异,但胆道支架置入术更能降低术后并发症风险、缓解腹痛症状,患者获益更多。 相似文献
6.
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
7.
Siraj A. Khan Jahnabi Saikia Trishna Bora Vinotsole Khamo Manju Rahi 《Indian journal of medical microbiology》2022,40(3):443-445
The antigenic heterogeneity of Orientia in India is still unknown in many disease endemic areas. The present study aims to characterize the strains of O. tsutsugamushi circulating in Nagaland, Northeast India. Two patients clinically diagnosed with ST and hospitalized in Mon district hospital, Nagaland were identified from whom eschar tissues were collected. Both patients demonstrated antibodies against O. tsutsugamushi along with positive PCR amplification for 56 ?kDa gene. The prototype strain TA763 shared 90.4% homology with the sequences. Both the sequences formed a distinctive cluster demonstrating 100% similarity with strains identified from Thailand, Vietnam, China and southern parts of India. 相似文献
8.
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9.
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
10.
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