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141.
目的:探讨骨化性肌炎的X线、CT、MRI、SPECT/CT的特征性表现。方法:回顾性分析56例经病理或随访证实为骨化性肌炎患者的影像学资料,总结其影像学特征,探讨该病的鉴别要点及诊断价值。结果:56例中,位于髋关节23例,肘关节18例,其他部位15例。早期病变12例,CT或MRI表现为软组织水肿、肿胀,无明显骨化成分,可合并邻近骨骼的骨膜反应;中期病变23例,表现为软组织内分层状肿块,病灶中心呈软组织密度或信号,病灶周围呈蛋壳样、絮状骨化影,SPECT/CT表现为病灶整体显像剂异常摄取;晚期病变21例,表现为边界清楚的骨化团块,SPECT/CT显像15例,其中3例未见显像剂摄取,6例病灶中央显像剂摄取,6例病灶周围显像剂不均匀摄取。结论:骨化性肌炎早期缺乏影像学特征,中期蛋壳样骨化是其特征表现,晚期的骨化团块可表现为不同形式的显像剂摄取,多模态影像学的综合应用可提高其临床诊断价值。 相似文献
142.
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating condition characterized by fatigue and post-exertional malaise, accompanied by various signs of neurological and autonomic dysfunction. ME/CFS is often triggered by an infectious episode and associated with an aberrant immune system. Here we report that ME/CFS is a disorder characterized by skewed B cell receptor gene usage. By applying a next-generation sequencing to determine the clone-based IGHV/IGHD/IGHJ repertoires, we revealed a biased usage of several IGHV genes in peripheral blood B cells from ME/CFS patients. Results of receiver operating characteristic (ROC) analysis further indicated a possibility of distinguishing patients from healthy controls, based on the skewed B cell repertoire. Meanwhile, B cell clones using IGHV3-30 and IGHV3-30-3 genes were more frequent in patients with an obvious infection-related episode at onset, and correlated to expression levels of interferon response genes in plasmablasts. Collectively, these results imply that B cell responses in ME/CFS are directed against an infectious agents or priming antigens induced before disease onset. 相似文献
143.
《International reviews of immunology》2013,32(3):195-211
There is increasing evidence that IFNg plays a major role in both induction of Tregs as well as immunosuppression mediated by IFNg-producing Tregs. The present review focuses on a small subset of iTregs that produces IFNg, comprises only 0.04% of all CD4+ T lymphocytes in the blood of healthy individuals, and increases strongly during an immune response. IFNg+ Tregs are induced by IFNg and IL12, making them sensors for inflammatory cytokines. They develop rapidly during inflammation and represent the first line of Tregs that suppress initial immune responses. The pool of IFNg+ Tregs consists of activated stable immunosuppressive thymus-derived nTregs as well as peripherally proliferating iTregs with in part only transient immunosuppressive function, which limits their diagnostic and therapeutic usefulness in organ transplantation. Apparently, a part of IFNg+ Tregs dies during the immune response, whereas others, after efficient immunosuppression with resolution of the immune response, differentiate toward Th1 lymphocytes. Goals of further research are the development of appropriate diagnostic tests for rapid and exact determinination of immunosuppressive IFNg+ iTregs, as well as the induction and propagation of stable immunosuppressive IFNg+ Tregs that establish and maintain good long-term graft function in transplant recipients. 相似文献
144.
Su-Jin Jeon Jong-Pil Yun Han-Gyeol Yeom Woo-Sang Shin Jong-Hyun Lee Seung-Hyun Jeong Min-Seock Seo 《Dento maxillo facial radiology》2021,50(5)
Objective:The aim of this study was to evaluate the use of a convolutional neural network (CNN) system for predicting C-shaped canals in mandibular second molars on panoramic radiographs.Methods:Panoramic and cone beam CT (CBCT) images obtained from June 2018 to May 2020 were screened and 1020 patients were selected. Our dataset of 2040 sound mandibular second molars comprised 887 C-shaped canals and 1153 non-C-shaped canals. To confirm the presence of a C-shaped canal, CBCT images were analyzed by a radiologist and set as the gold standard. A CNN-based deep-learning model for predicting C-shaped canals was built using Xception. The training and test sets were set to 80 to 20%, respectively. Diagnostic performance was evaluated using accuracy, sensitivity, specificity, and precision. Receiver-operating characteristics (ROC) curves were drawn, and the area under the curve (AUC) values were calculated. Further, gradient-weighted class activation maps (Grad-CAM) were generated to localize the anatomy that contributed to the predictions.Results:The accuracy, sensitivity, specificity, and precision of the CNN model were 95.1, 92.7, 97.0, and 95.9%, respectively. Grad-CAM analysis showed that the CNN model mainly identified root canal shapes converging into the apex to predict the C-shaped canals, while the root furcation was predominantly used for predicting the non-C-shaped canals.Conclusions:The deep-learning system had significant accuracy in predicting C-shaped canals of mandibular second molars on panoramic radiographs. 相似文献
145.
Vinicius Rosa Dean Ho Robinson Sabino-Silva Walter L. Siqueira Nikolaos Silikas 《Dental materials》2021,37(3):496-507
ObjectiveViruses on environmental surfaces, in saliva and other body fluids represent risk of contamination for general population and healthcare professionals. The development of vaccines and medicines is costly and time consuming. Thus, the development of novel materials and technologies to decrease viral availability, viability, infectivity, and to improve therapeutic outcomes can positively impact the prevention and treatment of viral diseases.MethodsHerein, we discuss (a) interaction mechanisms between viruses and materials, (b) novel strategies to develop materials with antiviral properties and oral antiviral delivery systems, and (c) the potential of artificial intelligence to design and optimize preventive measures and therapeutic regimen.ResultsThe mechanisms of viral adsorption on surfaces are well characterized but no major breakthrough has become clinically available. Materials with fine-tuned physical and chemical properties have the potential to compromise viral availability and stability. Emerging strategies using oral antiviral delivery systems and artificial intelligence can decrease infectivity and improve antiviral therapies.SignificanceEmerging viral infections are concerning due to risk of mortality, as well as psychological and economic impacts. Materials science emerges for the development of novel materials and technologies to diminish viral availability, infectivity, and to enable enhanced preventive and therapeutic strategies, for the safety and well-being of humankind. 相似文献
146.
目的:分析卵巢多房囊性病变的MRI误诊原因。方法:回顾性分析14例经手术病理证实的卵巢多房囊性病变的MRI及临床资料。结果:14例多房囊性病变中卵巢子宫内膜异位囊肿7例,多呈T1WI、T2WI高信号及大房周围多个小囊表现,3例可见液-液分层,1例术前被误诊为粘液性囊腺瘤;输卵管卵巢脓肿2例,呈病灶周围炎性及厚壁明显强化表现,术前均被误诊为卵巢肿瘤性病变;卵巢甲状腺肿1例,表现为多房囊实性病灶、实性部分及包膜明显强化,术前被误诊为囊腺癌;囊腺瘤/癌4例,术前MRI诊断无误。结论:MRI能清楚显示卵巢多房性病变,由于影像科医生对这些疾病尤其部分少见病的认识相对不足,常常导致误诊;在全面分析病变MRI信号特点的同时,加强业务知识更新,密切结合临床,很多误诊是可以避免的。 相似文献
147.
Jihang Kim Young Hoon Kim Kyoung Ho Lee Yoon Jin Lee Ji Hoon Park 《Korean journal of radiology》2015,16(3):541-549
Objective
To investigate the diagnostic performance of computed tomography angiography (CTA) in identifying the cause of bleeding and to determine the clinical features associated with a positive test result of CTA in patients visiting emergency department with overt gastrointestinal (GI) bleeding.Materials and Methods
We included 111 consecutive patients (61 men and 50 women; mean age: 63.4 years; range: 28-89 years) who visited emergency department with overt GI bleeding. They underwent CTA as a first-line diagnostic modality from July through December 2010. Two radiologists retrospectively reviewed the CTA images and determined the presence of any definite or potential bleeding focus by consensus. An independent assessor determined the cause of bleeding based on other diagnostic studies and/or clinical follow-up. The diagnostic performance of CTA and clinical characteristics associated with positive CTA results were analyzed.Results
To identify a definite or potential bleeding focus, the diagnostic yield of CTA was 61.3% (68 of 111). The overall sensitivity, specificity, positive predictive value (PPV), and negative predictive value were 84.8% (67 of 79), 96.9% (31 of 32), 98.5% (67 of 68), and 72.1% (31 of 43), respectively. Positive CTA results were associated with the presence of massive bleeding (p = 0.001, odds ratio: 11.506).Conclusion
Computed tomography angiography as a first-line diagnostic modality in patients presenting with overt GI bleeding showed a fairly high accuracy. It could identify definite or potential bleeding focus with a moderate diagnostic yield and a high PPV. CTA is particularly useful in patients with massive bleeding. 相似文献148.
Cyrus Behzadi Murat Karul Frank Oliver Henes Azien Laqmani Philipp Catala-Lehnen Wolfgang Lehmann Hans-Dieter Nagel Gerhard Adam Marc Regier 《World journal of radiology》2015,7(1):22-27
AIM: To determine the diagnostic accuracy and radiation dose of conventional radiography and multidetector computed tomography(MDCT) in suspected scaphoid fractures.METHODS: One hundred twenty-four consecutive patients were enrolled in our study who had suffered from a wrist trauma and showed typical clinical symptoms suspicious of an acute scaphoid fracture. All patients had initially undergone conventional radiography. Subsequent MDCT was performed within 10 d because of persisting clinical symptoms. Using the MDCT data as the reference standard, a fourfold table was used to classify the test results. The effective dose and impaired energy were assessed in order to compare the radiation burden of the two techniques. The Wilcoxon test was performed to compare the two diagnostic modalities.RESULTS: Conventional radiography showed 34 acute fractures of the scaphoid in 124 patients(42.2%). Subsequent MDCT revealed a total of 42 scaphoid fractures. The sensitivity of conventional radiography for scaphoid fracture detection was 42.8% and its specificity was 80% resulting in an overall accuracy of 59.6%. Conventional radiography was significantly inferior to MDCT(P < 0.01) concerning scaphoidfracture detection. The mean effective dose of MDCT was 0.1 m Sv compared to 0.002 m Sv of conventional radiography.CONCLUSION: Conventional radiography is insufficient for accurate scaphoid fracture detection. Regarding the almost negligible effective dose, MDCT should serve as the first imaging modality in wrist trauma. 相似文献
149.
Previous studies have shown that ethnic background hinders clinician detection of autistic features in children from non-western minority groups. The use of a structured instrument during evaluation of these children can reduce the risk of hindered detection. The aims of the current studies were to establish the extent of school-based professionals’ involvement in detecting autism and to replicate earlier findings of autism detection amongst school mentors. Results showed that school-based professionals were reported to be the first to suspect autistic features in 20% of children later diagnosed with autism. Additionally, school-based professionals refer to autism more often when judging children from majority than children from minority groups. However, using a structured instrument did not eliminate this bias. Providing these professionals with culture-sensitive education may help maximise their involvement in detecting autism amongst children from all ethnic backgrounds. 相似文献
150.
Ahmed Z Elmaadawi Peter S Jensen L Eugene Arnold Brooke SG Molina Lily Hechtman Howard B Abikoff Stephen P Hinshaw Jeffrey H Newcorn Laurence Lee Greenhill James M Swanson Cathryn A Galanter 《World Journal of Psychiatry》2015,5(4):412-424
AIM: To determine the prevalence of bipolar disorder (BD) and sub-threshold symptoms in
children with attention deficit hyperactivity disorder (ADHD) through 14 years’
follow-up, when participants were between 21-24 years old.METHODS: First, we examined rates of BD type I and II diagnoses in youth
participating in the NIMH-funded Multimodal Treatment Study of ADHD (MTA). We used the
diagnostic interview schedule for children (DISC), administered to both parents (DISC-P) and
youth (DISCY). We compared the MTA study subjects with ADHD (n = 579) to a
local normative comparison group (LNCG, n = 289) at 4 different assessment
points: 6, 8, 12, and 14 years of follow-ups. To evaluate the bipolar variants, we compared
total symptom counts (TSC) of DSM manic and hypomanic symptoms that were generated by DISC in
ADHD and LNCG subjects. Then we sub-divided the TSC into pathognomonic manic (PM) and
non-specific manic (NSM) symptoms. We compared the PM and NSM in ADHD and LNCG at each
assessment point and over time. We also evaluated the irritability as category A2 manic symptom
in both groups and over time. Finally, we studied the irritability symptom in correlation with
PM and NSM in ADHD and LNCG subjects.RESULTS: DISC-generated BD diagnosis did not differ significantly in rates between ADHD
(1.89%) and LNCG 1.38%). Interestingly, no participant met BD diagnosis more than once in the 4
assessment points in 14 years. However, on the symptom level, ADHD subjects reported
significantly higher mean TSC scores: ADHD 3.0; LNCG 1.7; P < 0.001. ADHD
status was associated with higher mean NSM: ADHD 2.0 vs LNCG 1.1;
P < 0.0001. Also, ADHD subjects had higher PM symptoms than LNCG, with PM
means over all time points of 1.3 ADHD; 0.9 LNCG; P = 0.0001. Examining both
NSM and PM, ADHD status associated with greater NSM than PM. However, Over 14 years, the NSM
symptoms declined and changed to PM over time (df 3, 2523; F = 20.1; P <
0.0001). Finally, Irritability (BD DSM criterion-A2) rates were significantly higher in ADHD
than LNCG (χ2 = 122.2, P < 0.0001), but irritability was
associated more strongly with NSM than PM (df 3, 2538; F = 43.2; P <
0.0001).CONCLUSION: Individuals with ADHD do not appear to be at significantly greater risk for
developing BD, but do show higher rates of BD symptoms, especially NSM. The greater linkage of
irritability to NSM than to PM suggests caution when making BD diagnoses based on irritability
alone as one of 2 (A-level) symptoms for BD diagnosis, particularly in view of its frequent
presentation with other psychopathologies. 相似文献