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Rheumatoid arthritis may be primarily associated with HLA-DR4 molecules sharing a particular sequence at residues 67–74 总被引:2,自引:0,他引:2
Kjersti S. Rønningen Anne Spurkland Torstein Egeland Thomas Iwe Eimar Munthe Frode Vartdal Erik Thorsby 《Tissue antigens》1990,36(5):235-240
Genomic typing of in vitro amplified DNA with sequence-specific oligonucleotide (SSO) probes was performed for DRB1, DQA1, DQB1, DPA1 and DPB1 alleles in 54 random Norwegian rheumatoid arthritis (RA) patients and 181 healthy controls. DRB1 alleles encoding the serological specificity DR4 were found in 80% of the patients, compared to 34% of the controls (relative risk = 7.9, p less than 0.0001). All DR4-positive RA patients carried either DRB1*0401 (Dw4), 0404 (Dw14), or 0405 (Dw15), while no patients were found to carry DRB1*0402 (Dw10) or 0403 (Dw13). The frequency of the DRB1*0101 allele encoding DR1 was not increased, even among DR4-negative RA patients, and we were unable to detect any sharing of other class II alleles among DR4-negative patients. No contribution of any DQA1, DQB1, DPA1 or DPB1 alleles to RA susceptibility could be detected. The results suggest that in the Norwegian population RA is primarily associated with a shared sequence at residues 67-74 of the DR beta 1 chain, but only when this sequence is expressed on DR4 molecules. 相似文献
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Feasibility of assessment of coronary stent patency using 16-slice computed tomography 总被引:27,自引:0,他引:27
Schuijf JD Bax JJ Jukema JW Lamb HJ Warda HM Vliegen HW de Roos A van der Wall EE 《The American journal of cardiology》2004,94(4):427-430
Intracoronary stent implantation is a frequently performed procedure in the treatment of stenoses in coronary arteries, but in-stent restenosis occurs in approximately 10% to 15% of patients. A noninvasive diagnostic procedure to evaluate in-stent restenosis would therefore be of great benefit. We investigated the feasibility of assessing stent patency with 16-slice computed tomography. Multislice computed tomography (MSCT) was performed in 22 patients with previously implanted stents. For each stent, assessability was determined and related to stent type and diameter. Subsequently, the presence of significant restenosis was determined in the evaluable stents. In addition, peristent lumina (5 mm proximal and distal to the stent) were evaluated. Conventional angiography in combination with quantitative coronary angiography served as the standard of reference. MSCT was performed successfully in all but 1 patient. Of 65 stents, 50 (77%) were determined assessable. Uninterpretable stents tended to have a thicker strut and/or a smaller diameter. In the evaluable stents, 7 of 9 stenoses were detected and the absence of restenosis was correctly identified in all 41 patent stents, resulting in a sensitivity and specificity of 78% and 100%, respectively. Sensitivity and specificity for the detection of peristent stenosis were 75% and 96%, respectively. In conclusion, MSCT may be useful in the assessment of stent patency and may function as a gatekeeper before invasive diagnostic procedures. 相似文献
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Ruobing Qian Ryan P. McNabb Kevin C. Zhou Hazem M. Mousa Daniel R. Saban Victor L. Perez Anthony N. Kuo Joseph A. Izatt 《Biomedical optics express》2021,12(4):2134
Anterior uveitis is the most common form of intraocular inflammation, and one of its main signs is the presence of white blood cells (WBCs) in the anterior chamber (AC). Clinically, the true composition of cells can currently only be obtained using AC paracentesis, an invasive procedure to obtain AC fluid requiring needle insertion into the AC. We previously developed a spectroscopic optical coherence tomography (SOCT) analysis method to differentiate between populations of RBCs and subtypes of WBCs, including granulocytes, lymphocytes and monocytes, both in vitro and in ACs of excised porcine eyes. We have shown that different types of WBCs have distinct characteristic size distributions, extracted from the backscattered reflectance spectrum of individual cells using Mie theory. Here, we further develop our method to estimate the composition of blood cell mixtures, both in vitro and in vivo. To do so, we estimate the size distribution of unknown cell mixtures by fitting the distribution observed using SOCT with a weighted combination of reference size distributions of each WBC type calculated using kernel density estimation. We validate the accuracy of our estimation in an in vitro study, by comparing our results for a given WBC sample mixture with the cellular concentrations measured by a hemocytometer and SOCT images before mixing. We also conducted a small in vivo quantitative cell mixture validation pilot study which demonstrates congruence between our method and AC paracentesis in two patients with uveitis. The SOCT based method appears promising to provide quantitative diagnostic information of cellular responses in the ACs of patients with uveitis. 相似文献
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Sensitivity and Specificity of Radiographic Methods for Predicting Insertion Torque of Dental Implants 下载免费PDF全文
Arthur Rodriguez Gonzalez Cortes Hazem Eimar Jorge de Sá Barbosa Claudio Costa Emiko Saito Arita Faleh Tamimi 《Journal of periodontology》2015,86(5):646-655
Background: Subjective radiographic classifications of alveolar bone have been proposed and correlated with implant insertion torque (IT). The present diagnostic study aims to identify quantitative bone features influencing IT and to use these findings to develop an objective radiographic classification for predicting IT. Methods: Demographics, panoramic radiographs (taken at the beginning of dental treatment), and cone‐beam computed tomographic scans (taken for implant surgical planning) of 25 patients receiving 31 implants were analyzed. Bone samples retrieved from implant sites were assessed with dual x‐ray absorptiometry, microcomputed tomography, and histology. Odds ratio, sensitivity, and specificity of all variables to predict high peak IT were assessed. Results: A ridge cortical thickness >0.75 mm and a normal appearance of the inferior mandibular cortex were the most sensitive variables for predicting high peak IT (87.5% and 75%, respectively). A classification based on the combination of both variables presented high sensitivity (90.9%) and specificity (100%) for predicting IT. Conclusions: Within the limitations of this study, the results suggest that it is possible to predict IT accurately based on radiographic findings of the patient. This could be useful in the treatment plan of immediate loading cases. 相似文献
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Ahmed Youssef Altonbary Hazem Hakim Wagdi Elkashef 《World journal of gastrointestinal endoscopy》2020,12(10):355-364
BACKGROUND Although endoscopic ultrasound(EUS) is now widely available and has an established role in adults, the utility of EUS and EUS-guided fine needle aspiration(EUS-FNA) in pediatrics is insufficiently described compared to adults and is supported by only a few studies.AIM To report the experience of a single tertiary center in the use of EUS and EUS-FNA in a pediatric population and to further assess its safety, feasibility, and clinical impact on management.METHODS A retrospective study of 13 children(aged 18 years or younger) identified from our medical database was conducted. A retrospective review of demographic data, procedure indications, EUS findings, and the clinical impact of EUS on the subsequent management of these patients was performed.RESULTS During the 4-year study period, a total of 13(1.7%) pediatric EUS examinations out of 749 EUS procedures were performed in our unit. The mean age of these 8 females and 5 males was 15.6 years(range: 6-18). Six of the 13 EUS examinations were pancreatobiliary(46.1%), followed by mediastinal 2/13(15.4%), peri-gastric 2/13(15.4%), abdominal lymphadenopathy 1/13(7.7%), tracheal 1/13(7.7%) and rectal 1/13(7.7%). Overall, EUS-FNA was performed in 7 patients(53.8%) with a diagnostic yield of 100%. The EUS results had a significant impact on clinical care in 10/13(77%) cases. No complications occurred in these patients during or after any of the procedures.CONCLUSION EUS and EUS-FNA in the pediatric population are safe, feasible, and have a significant clinical impact on the subsequent management; thus avoiding invasive and unnecessary procedures. 相似文献
9.
Yasser M. Aljehani Sharifah A. Othman Nosibah K. Telmesani Raghad A. Alghamdi Hussah M. AlBuainain Zeead M. Alghamdi Hazem M. Zakaria Farouk T. Alreshaid Saleh A. Busbait Abdullah A. Alqarzaie Turki M. Alharbi Ruba K. Alnajim 《Saudi medical journal》2020,41(12):1344
Objectives:To evaluate the impact of coronavirus-19 (COVID-19) pandemic and its consequences on general surgery residents.Methods:Cross-sectional, survey based study including surgical residents in Kingdom of Saudi Arabia and Kingdom of Bahrain.Results:Surgical trainees who participated in our survey (n=234) were young (mean age 28), single (53.8%), and males (65.8%). Approximately half (50.4%) have been deployed to cover the staff shortage in intensive care units (ICUs) or emergency departments (EDs). Half of our trainees (117) scored positive in the screening tool of generalized anxiety disorder (GAD). There was a significant association between experiencing anxiety and male gender (p=0.055), level of training (p=0.002), deployment to cover ICUs (p=0.050), testing positive for COVID-19 (p=0.054) and having an infected family member (p=0.004).Conclusion:Coronavirus-19 pandemic has a serious effect on all healthcare workers and surgical residents have experienced a considerable amount of stress. Accordingly, this psychological burden should be appropriately addressed in organizations planning strategies. We suggest formulating guidelines to help surgical trainees to continue their learning process with least psychological burden. 相似文献
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